A potentially significant severe weather outbreak across much of the northeast, including our area is beginning. However, Grotonweather.com will NOT be going into alert mode for this event. As I mentioned in the Alert Mode blog, I take the issuing of Alert Mode very seriously. I only issue them when it seems like widespread, life threatening weather is likely.
Today's event is very close to that criteria, and I cannot say for sure that I will not issue Alert Mode status later in the day. At this point though, I do not think the storms will organize quite fast enough to bring the high risks necessary for an Alert Mode. If this site was for Chenango, Monroe and Otsego counties, I very likely would be going into Alert Mode. The worst of this event, in terms of spatial coverage and intensity, will likely be just to our east.
That being said, storms are already starting to develop in our area and just to the west. These storms will not take long to become severe, and our threats for wind damage and hail remain at a 'MODERATE' level. Winds up to 80mph and two inch hail are not totally out of the question. Stay tuned for updates!
Showing posts with label t-storms. Show all posts
Showing posts with label t-storms. Show all posts
Thursday, June 09, 2011
Monday, May 02, 2011
Severe Weather Awareness Week
This week is Severe Weather Awareness Week. In light of the recent severe and tornadic thunderstorms, I think its very important that we realize that dangerous and deadly weather can and does occur in our area. The first step to keeping yourself safe is education. I will be updating this blog each day with links to the National Weather Service pages for each day of Severe Weather Awareness Week.
Monday- Overview
Tuesday- Severe Thunderstorms
Wednesday- Severe Weather Preparedness
Thursday- Tornado Watches & Warnings
Friday- Flood Preparedness
Saturday- Communication of Hazardous Weather Information
Monday- Overview
Tuesday- Severe Thunderstorms
Wednesday- Severe Weather Preparedness
Thursday- Tornado Watches & Warnings
Friday- Flood Preparedness
Saturday- Communication of Hazardous Weather Information
Wednesday, July 21, 2010
1PM Severe Weather Update
2PM Update: SEVERE THUNDERSTORM WARNING FOR S. CAYUGA COUNTY UNTIL 2:45 pm. A severe storm over Ontario county will move into S. Cayuga county over the next 30-60 minutes. I expect the warning to be extended/overlapped as the storm moves into the area. If the storm remains severe (and there is not really any reason for it not to), Groton, Homer and Cortland will have to watch out for this storm between 3-4 pm. Interesting note: All of the Grotonweather forecast area but extreme northeast Tompkins and northern Cortland Counties have been under severe thunderstorm warnings at some point today already! And our watch goes for 6 more hours.
Original 1PM post: Lots going on this afternoon already. A severe storm tore through central Tompkins county last hour. It is looking a bit less organized as it moves into S. Cortland county. I was in Ithaca, on the 11th floor of Bradfield Hall, Cornell as the storm passed. There was rotation with it, and I got some awesome pictures I will post tonight. The storm produced 1" hail in Trumansburg and took out "many" trees and powerlines in Lansing. No other reports yet (as of 1PM).
While all this was going on, the SPC moved us into a moderate risk. This is primarily for the threat of damaging winds. Now, we've already experienced severe weather...but is more on the way? Our watch goes until 8pm, afterall. The answer is yes, our threat still continues. There are more showers and storms forming over western New York back into Canada. The cold front itself stretches from Ontario back into Ohio and Indiana. The air just upstream is very unstable, and the storms we've already had shouldn't have much of an effect on our instability for the middle or latter part of the afternoon.
If you haven't become a fan of Grotonweather on facebook or a follower on Twitter, you will want to do so now! I've been posting up a storm (pun intended) on those two sites all morning with the latest updates and will continue to do so through the day. Also, the Grotonweather Toolbar is a great way to keep your eye on the latest forecast. Download it here. And, as always, the main site/blog will be updated throughout the day to keep you safe!
That's all for now. Keep checking back!
Original 1PM post: Lots going on this afternoon already. A severe storm tore through central Tompkins county last hour. It is looking a bit less organized as it moves into S. Cortland county. I was in Ithaca, on the 11th floor of Bradfield Hall, Cornell as the storm passed. There was rotation with it, and I got some awesome pictures I will post tonight. The storm produced 1" hail in Trumansburg and took out "many" trees and powerlines in Lansing. No other reports yet (as of 1PM).
While all this was going on, the SPC moved us into a moderate risk. This is primarily for the threat of damaging winds. Now, we've already experienced severe weather...but is more on the way? Our watch goes until 8pm, afterall. The answer is yes, our threat still continues. There are more showers and storms forming over western New York back into Canada. The cold front itself stretches from Ontario back into Ohio and Indiana. The air just upstream is very unstable, and the storms we've already had shouldn't have much of an effect on our instability for the middle or latter part of the afternoon.If you haven't become a fan of Grotonweather on facebook or a follower on Twitter, you will want to do so now! I've been posting up a storm (pun intended) on those two sites all morning with the latest updates and will continue to do so through the day. Also, the Grotonweather Toolbar is a great way to keep your eye on the latest forecast. Download it here. And, as always, the main site/blog will be updated throughout the day to keep you safe!
That's all for now. Keep checking back!
Monday, August 10, 2009
Ticking Time Bomb
I like severe thunderstorms. They are fun to try to forecast and I find them exciting to experience. I of course don't like it when they do major damage or pose a significant threat to the safety of people. So, you could say there is a certain intangible threshold where a situation goes from enjoyable, to scary. I think we've already crossed that threshold today, and the nearest storms are just starting to pop in eastern Michigan.
Now, if you checked my site early this morning, you would have seen that I had taken it down and had prepared it to sit dormant for the next 10 days or so due to a variety of circumstances. However, things are evolving in such a way that I really feel like I need to be updating today.
Ok, so whats going on. If you haven't stepped outside lately, go do so. You will be greeted by a blast of heat and oppressive humidity when you do. Temperatures have already shot up into the 80s, and dewpoints are in the low 70s. This has already led to instability levels that are rare for our area, and high even by the standards of the Great Plains. So often, I talk about the role of cloud cover in severe weather outbreaks. Often times in our area, clouds in the morning and early afternoon inhibit destabilization, which is why we don't see extreme instability like we are seeing now very often. But it has been sunny and will continue to be sunny through the afternoon, which means things will only continue to destabilze to levels that far exceed anything we have seen this year, possibly even the past few years.
Instability alone is not enough to create a severe weather outbreak. You also need a trigger to get storms going. For us, that is a disturbance moving towards the east along a cold front. Right now, it is over southern Michigan...which is why the storms are forming there. As it moves east, this energy will provide the lift needed to allow storms to continue to form. As they interact with the unstable air, they will intensify. One more piece is needed though, and that is shear, or a change in wind speed or direction with height or horizontal distance. In this case, we are looking at speed shear from both the ground up into the atmosphere, and horizontally from south to north. This is because of an area of strong winds in the jet stream called a 'jet streak' that is to our north. This will provide the shear needed to organize the storms into segments, or even a squall line.
The way I see it right now, all of the ingredients are evolving to come together for a significant severe weather event for all of Central New York. The only question I really have is whether or not a massive squall line will form out of those storms in Michigan, or if there will be multiple, but smaller lines of storms. That is something that will only be determined as the afternoon goes on. Regardless, there is the potential for strong, destructive winds after roughly 4pm tonight. It wouldn't hurt to take some precautions now by putting away lawn furniture, securing loose objects, etc. The biggest threat from the storms is definatly wind and, if I was updating my site as normal, I would likely place it in the 'high' category. I believe that most, if not all counties in Central New York will experience at least some wind damage to trees.
Another danger tonight will be flash flooding....some areas, especially in Cortland County, got 3"+ of rain yesterday, with mudslides and road closures overnight in Cortland County. It won't take much heavy rain to create more problems. NEVER drive through a flooded roadway! Flooding is the number 1 weather killer in the United States, and most of those fatalities occur in automobiles.
Watch for another update between 3 and 5pm, or sooner if a watch comes out. This is one forecast I hope I am not right on.
Now, if you checked my site early this morning, you would have seen that I had taken it down and had prepared it to sit dormant for the next 10 days or so due to a variety of circumstances. However, things are evolving in such a way that I really feel like I need to be updating today.
Ok, so whats going on. If you haven't stepped outside lately, go do so. You will be greeted by a blast of heat and oppressive humidity when you do. Temperatures have already shot up into the 80s, and dewpoints are in the low 70s. This has already led to instability levels that are rare for our area, and high even by the standards of the Great Plains. So often, I talk about the role of cloud cover in severe weather outbreaks. Often times in our area, clouds in the morning and early afternoon inhibit destabilization, which is why we don't see extreme instability like we are seeing now very often. But it has been sunny and will continue to be sunny through the afternoon, which means things will only continue to destabilze to levels that far exceed anything we have seen this year, possibly even the past few years.
Instability alone is not enough to create a severe weather outbreak. You also need a trigger to get storms going. For us, that is a disturbance moving towards the east along a cold front. Right now, it is over southern Michigan...which is why the storms are forming there. As it moves east, this energy will provide the lift needed to allow storms to continue to form. As they interact with the unstable air, they will intensify. One more piece is needed though, and that is shear, or a change in wind speed or direction with height or horizontal distance. In this case, we are looking at speed shear from both the ground up into the atmosphere, and horizontally from south to north. This is because of an area of strong winds in the jet stream called a 'jet streak' that is to our north. This will provide the shear needed to organize the storms into segments, or even a squall line.
The way I see it right now, all of the ingredients are evolving to come together for a significant severe weather event for all of Central New York. The only question I really have is whether or not a massive squall line will form out of those storms in Michigan, or if there will be multiple, but smaller lines of storms. That is something that will only be determined as the afternoon goes on. Regardless, there is the potential for strong, destructive winds after roughly 4pm tonight. It wouldn't hurt to take some precautions now by putting away lawn furniture, securing loose objects, etc. The biggest threat from the storms is definatly wind and, if I was updating my site as normal, I would likely place it in the 'high' category. I believe that most, if not all counties in Central New York will experience at least some wind damage to trees.
Another danger tonight will be flash flooding....some areas, especially in Cortland County, got 3"+ of rain yesterday, with mudslides and road closures overnight in Cortland County. It won't take much heavy rain to create more problems. NEVER drive through a flooded roadway! Flooding is the number 1 weather killer in the United States, and most of those fatalities occur in automobiles.
Watch for another update between 3 and 5pm, or sooner if a watch comes out. This is one forecast I hope I am not right on.
Saturday, July 11, 2009
Risks Upgraded
There have been a couple of changes in the forecast this morning as things area already rapidly evolving. Probably the most significant of these changes is that, instead of all the clouds and rain the models had been forecasting for us this morning, skies are clear. This is causing the atmosphere to destabilize quicker and more intensely than had been forecasted. Another thing to look at is the radar. Thunderstorms are widespread just west of Buffalo, and already, there are some storms popping out ahead of this main area...so the question of whether or not storms will form is out the window.
The Storm Prediction Center has us in a 30-30-5% risk for wind-hail-tornadoes, respectively. All three of those are on the upper end of their 'slight' risk category. After looking at a couple things, I moved my hail and win up to moderate, and kept tornadoes at slight. Since storms are already firing, I moved the thunderstorm risk all the way up, which the NWS in Binghamton also did on their threat outlooks.
Here is what I am expecting for each threat:
Thunderstorms: Extreme-
Widespread thunderstorms can be expected with almost everywhere getting a storm. Frequent lightning should accompany the storms, and a fair number of them will likely be severe.
Wind: Moderate-
With the sun out this morning and strong upper level winds, wind damage is likely somewhere in Central New York, with some possibility of widespread damaging winds. 3 to 7 damaging wind reports are possible in the Grotonweather forecast area (Tompkins, S. Cayuga and Cortland Counties), with more elsewhere in Central New York. Should a widespread wind event evolve, this will be increased to high.
Hail: Moderate-
With extra instablity from the sun this morning, and indications of favorable hail formation from both the models, and current observations, hail could become a major factor today. 3 to 7 severe (0.75" of bigger) hail reports in the forecast area is possible, with more elsewhere in Central New York. Hail sizes should stay below 1.5", but an isolated storm could produce up to 2" hail. An upgrade to a high risk is not expected at this time.
Tornadoes: Slight-
Little changes to the tornado forecast have been made. A tornado somewhere in Western and Central New York seems almost likely. Multiple tornadoes could be possible, but this certainty isn't enough for a moderate risk at the time. However, with strong southeast winds at the surface, winds at low levels out of the southwest, and upper level winds coming in from the west, the threat for tornadoes will need to be watched closely.
The Storm Prediction Center has us in a 30-30-5% risk for wind-hail-tornadoes, respectively. All three of those are on the upper end of their 'slight' risk category. After looking at a couple things, I moved my hail and win up to moderate, and kept tornadoes at slight. Since storms are already firing, I moved the thunderstorm risk all the way up, which the NWS in Binghamton also did on their threat outlooks.
Here is what I am expecting for each threat:
Thunderstorms: Extreme-
Widespread thunderstorms can be expected with almost everywhere getting a storm. Frequent lightning should accompany the storms, and a fair number of them will likely be severe.
Wind: Moderate-
With the sun out this morning and strong upper level winds, wind damage is likely somewhere in Central New York, with some possibility of widespread damaging winds. 3 to 7 damaging wind reports are possible in the Grotonweather forecast area (Tompkins, S. Cayuga and Cortland Counties), with more elsewhere in Central New York. Should a widespread wind event evolve, this will be increased to high.
Hail: Moderate-
With extra instablity from the sun this morning, and indications of favorable hail formation from both the models, and current observations, hail could become a major factor today. 3 to 7 severe (0.75" of bigger) hail reports in the forecast area is possible, with more elsewhere in Central New York. Hail sizes should stay below 1.5", but an isolated storm could produce up to 2" hail. An upgrade to a high risk is not expected at this time.
Tornadoes: Slight-
Little changes to the tornado forecast have been made. A tornado somewhere in Western and Central New York seems almost likely. Multiple tornadoes could be possible, but this certainty isn't enough for a moderate risk at the time. However, with strong southeast winds at the surface, winds at low levels out of the southwest, and upper level winds coming in from the west, the threat for tornadoes will need to be watched closely.
Friday, July 10, 2009
Friday Afternoon's Severe Weather Outlook for 7/11
I spent the morning and early afternoon down at the National Weather Service in Binghamton, where I am an intern this summer, and used some of their in-house tools to try to get a better handle on the severe weather threat tomorrow. I will mention that the meteorologists there this morning believe tomorrow will be an active day and seem to have a high confidence level.
One of the tools I used this morning was a form called the 'severe weather checklist'. This form has you enter in forecasted values for a variety of severe weather parameters. After doing so, it returns the 5 most similar severe weather days in recent Central New York history. When completing this checklist this morning, it returned 4 days of 'isolated supercells', including May 16th, 2009, which had 3 tornadoes in the area, and May 31, 2002, which had 4 tornadoes. The fifth day was classified as a 'broken line'. Hail was the primary threat from the five days collectively. That tells me that not everywhere tomorrow will see a strong thunderstorm....some areas may barely even get any rain. However, there is certainly potential for some severe weather, and someone will likely have to deal with a damaging storm.
Here is a glance at where I have my threat levels, and an in depth look at exactly what I mean by each threat level, as well as what would need to happen for an upgraded risk:
Thunderstorms: moderate-
Thunderstorms are likely across much of the area. A few places, however, will be missed and get little to no rain. Frequent lightning will accompany some of the storms.
High Winds: slight-
Some storms may contain strong winds. Wind damage will be isolated to scattered, with 3 to 10 reports in Central New York. Sunshine in the morning would increase the chances of wind damage, and could get this bumped up to a moderate risk.
Hail: slight-
Small hail will be possible with stronger storms tomorrow, but most hail should remain uner 1" in diameter. The strongest storms may produce up to 1.5" hail. 5-12 Severe hail (over 0.75") events can be expected in Central New York. This is still rather uncertain, and could be upgraded to a moderate risk should the models show a bit better conditions for hail tomorrow morning.
Tornadoes: slight-
Conditions are favorable for rotating storms, and tornadoes could form. My best current guess is that somewhere in Western, Central and Southern New York will see a weak tornado, but as many as 2 or 3 wouldn't surprise me. This would most likely not be upgraded to moderate unless numerous storms that have already developed are showing signs of becoming tornadic.
Expect the next website update to occur between 9 and 11 am tomorrow. A blog update should occur within 30 minutes of that. There also could be a quick blog update tonight. During the afternoon tomorrow, I plan to have the weather chat open and will be updating th blog and website as needed. Stay tuned!
One of the tools I used this morning was a form called the 'severe weather checklist'. This form has you enter in forecasted values for a variety of severe weather parameters. After doing so, it returns the 5 most similar severe weather days in recent Central New York history. When completing this checklist this morning, it returned 4 days of 'isolated supercells', including May 16th, 2009, which had 3 tornadoes in the area, and May 31, 2002, which had 4 tornadoes. The fifth day was classified as a 'broken line'. Hail was the primary threat from the five days collectively. That tells me that not everywhere tomorrow will see a strong thunderstorm....some areas may barely even get any rain. However, there is certainly potential for some severe weather, and someone will likely have to deal with a damaging storm.
Here is a glance at where I have my threat levels, and an in depth look at exactly what I mean by each threat level, as well as what would need to happen for an upgraded risk:
Thunderstorms: moderate-
Thunderstorms are likely across much of the area. A few places, however, will be missed and get little to no rain. Frequent lightning will accompany some of the storms.
High Winds: slight-
Some storms may contain strong winds. Wind damage will be isolated to scattered, with 3 to 10 reports in Central New York. Sunshine in the morning would increase the chances of wind damage, and could get this bumped up to a moderate risk.
Hail: slight-
Small hail will be possible with stronger storms tomorrow, but most hail should remain uner 1" in diameter. The strongest storms may produce up to 1.5" hail. 5-12 Severe hail (over 0.75") events can be expected in Central New York. This is still rather uncertain, and could be upgraded to a moderate risk should the models show a bit better conditions for hail tomorrow morning.
Tornadoes: slight-
Conditions are favorable for rotating storms, and tornadoes could form. My best current guess is that somewhere in Western, Central and Southern New York will see a weak tornado, but as many as 2 or 3 wouldn't surprise me. This would most likely not be upgraded to moderate unless numerous storms that have already developed are showing signs of becoming tornadic.
Expect the next website update to occur between 9 and 11 am tomorrow. A blog update should occur within 30 minutes of that. There also could be a quick blog update tonight. During the afternoon tomorrow, I plan to have the weather chat open and will be updating th blog and website as needed. Stay tuned!
Saturday, May 09, 2009
A Look at Watch #280
The Storm Prediction Center has issued a Severe Thunderstorm Watch that stretches across almost all of New York State. It remains in effect until 7pm tonight. Here is a look at the exact counties it includes. As you can see, Tompkins, Cortland and S. Cayuga are right in the middle of it.
The main threat from this event is going to be damaging winds. Hail will also be possible, and my gut feeling is there will be a tornado somewhere in the watch box. The official probabilities that the SPC has put with the watch:
Tornadoes
Wind
Hail
Combined Severe Hail/Wind
Since it is at the top of the hour, the current observations and indicies will not be in for another 20-40 minutes. Looking at the data from noon, though, it is obvious to me that the atmosphere is quickly destabilizing. Also, a pocket of strong winds in the upper atmosphere is beginning to move into Western New York, and will spread over the rest of the state, enhancing the thunderstorms. Storms are going to develop from west to east, and have already begun to fire up across Western New York, Lake Erie and Lake Ontario. These storms should organize into a squall line eventually, which is when the greatest threat for wind damage will be. The highest tornado and hail threat will be just prior to that, when the storms are more individual cells.
Be sure to keep checking back through the afternoon for the latest!
The main threat from this event is going to be damaging winds. Hail will also be possible, and my gut feeling is there will be a tornado somewhere in the watch box. The official probabilities that the SPC has put with the watch:
Tornadoes
| Probability of 2 or more tornadoes | Low (20%) |
| Probability of 1 or more strong (F2-F5) tornadoes | Low (5%) |
| Probability of 10 or more severe wind events | Mod (60%) |
| Probability of 1 or more wind events > 65 knots | Mod (30%) |
| Probability of 10 or more severe hail events | Mod (30%) |
| Probability of 1 or more hailstones > 2 inches | Low (20%) |
| Probability of 6 or more combined severe hail/wind events | High (80%) |
Since it is at the top of the hour, the current observations and indicies will not be in for another 20-40 minutes. Looking at the data from noon, though, it is obvious to me that the atmosphere is quickly destabilizing. Also, a pocket of strong winds in the upper atmosphere is beginning to move into Western New York, and will spread over the rest of the state, enhancing the thunderstorms. Storms are going to develop from west to east, and have already begun to fire up across Western New York, Lake Erie and Lake Ontario. These storms should organize into a squall line eventually, which is when the greatest threat for wind damage will be. The highest tornado and hail threat will be just prior to that, when the storms are more individual cells.
Be sure to keep checking back through the afternoon for the latest!
Friday, December 19, 2008
Morning Storm Update
It is now quarter after 10am, and everything is going pretty much as expected. The snow started here in Groton about an hour ago, and already visibilities are down to roughly a mile as the snow has started to pick up in intensity. Looking at the official 10AM observations, Ithaca is reporting light snow, with moderate snow in Rochester, Penn Yan, and Dansville, and heavy snow falling in Buffalo. Over the next hour, expect the snow to continue to increase in intensity to the rate of an inch or so an hour. The snow will continue at least at that intensity, likely reaching 2" per hour at times, through the afternoon. Heavy and moderate snow is being reported back through Michigan. There is actually heavy snow in Wisconsin as well, but I think Lake Michigan is enhancing that snow since the winds are out of the northeast. Here is a look at the radar (from 9:30...but that is recent enough to get the point across). You can see any mixed precipitation is well south, and the snow extends back into the areas I just described. All this is moving more or less east-southeast.
Bottom line is the snow is going to come down hard very soon and continue at rates of 1-2" per hour until at least sundown. There may even be some thunder and lightning in the snow during the early and mid afternoon. Please leave a comment here, or log onto the chat (assuming it is open) and report any thunder! The chat room will likely be open most of the day today as well. I will continue to update this blog hourly, probably just with snow totals, but also any new information that comes in.
Bottom line is the snow is going to come down hard very soon and continue at rates of 1-2" per hour until at least sundown. There may even be some thunder and lightning in the snow during the early and mid afternoon. Please leave a comment here, or log onto the chat (assuming it is open) and report any thunder! The chat room will likely be open most of the day today as well. I will continue to update this blog hourly, probably just with snow totals, but also any new information that comes in.
Sunday, September 14, 2008
Abnormal September Tornado Threat
I can't say I saw this one coming, but I get up this morning and almost everything I look at points to today being a rough day across parts of Central New York. Last year in meteorology class, we went over tornado forecasting in quite some detail. A lot of the things we were told to look for have started to line up. The one thing that will probably prevent this from being an outbreak is the fact that the air aloft isn't all that cold. That warm air aloft should help keep the instability less than it would be on other days that are this humid. Regardless to say, the Storm Prediction Center has us in their '5%' chance of tornadoes.
There are meteorologists, however, who do not like the SPC's % system. One of them is Accuweather Senior Meteorologist Henry Margusity, who I have mentioned many times. Over the summer, he developed a scale to better address the threats of severe thunderstorms. His scale goes from 1-4 and outlines specific threats for each category. You will likely have to click the image to read it, but here is a look at his system:
Henry has placed us in his T3 Category today mainly for the tornado threat. It will be interesting to see how this one unfolds. Stay tuned!
There are meteorologists, however, who do not like the SPC's % system. One of them is Accuweather Senior Meteorologist Henry Margusity, who I have mentioned many times. Over the summer, he developed a scale to better address the threats of severe thunderstorms. His scale goes from 1-4 and outlines specific threats for each category. You will likely have to click the image to read it, but here is a look at his system:
Henry has placed us in his T3 Category today mainly for the tornado threat. It will be interesting to see how this one unfolds. Stay tuned!
Sunday, June 29, 2008
Split Forecast Area
The grotonweather.com forecast area has been split by Severe Thunderstorm Watch 638. Cayuga County is under the watch, while Tompkins and Cortland got left out. In all honesty, however, that is just a technicality. Conditions are just as favorable for severe thunderstorms in Tompkins and Cortland Counties as they are in Cayuga...the SPC has to draw the line somewhere, however. I am expecting another watch to be issued later this afternoon that will include the rest of the area.
Numerous thunderstorms have developed over Western New York and Western Pennsylvania. These storms will track east, with damaging winds and hail the main threats. Other storms will develop as well, so it looks like we may have a decent severe weather event on our hands.
Numerous thunderstorms have developed over Western New York and Western Pennsylvania. These storms will track east, with damaging winds and hail the main threats. Other storms will develop as well, so it looks like we may have a decent severe weather event on our hands.
Sunday, June 22, 2008
Severe Thunderstorm Watch
Thunderstorms have begun to develop all across the Northeast and Ohio Valley, including Central and Western New York. This has prompted the Storm Prediction Center to issue a Severe Thunderstorm Watch for all of the counties shaded in blue below, including Tompkins County pretty much smack dab in the middle of the watch:
The probabilities with this watch indicate that the SPC is most concerned with hail, followed closely by damaging winds. The chances of 10 or more hail reports in the watch area is 70%, with a 50% chance of 10 or more hail reports.
Looking at the regional radar, you can see lots of thunderstorms scattered about the area. These will continue to develop, increasing in strength and coverage.
Stay tuned for any warnings!
The probabilities with this watch indicate that the SPC is most concerned with hail, followed closely by damaging winds. The chances of 10 or more hail reports in the watch area is 70%, with a 50% chance of 10 or more hail reports.
Looking at the regional radar, you can see lots of thunderstorms scattered about the area. These will continue to develop, increasing in strength and coverage.
Stay tuned for any warnings!
Monday, June 16, 2008
Watch Issued
Severe Thunderstorm Watch #550 has been issued. This is quite a massive watch, encompasing most of New York and about 70% of Pennsylvania. With a watch that large, probablities aren't overly helpful for local forecasts. Nonetheless, there is an 80% chance of 10+ wind damage reports and a 70% chance of 10+ hail reports within the watch area. The watch runs until 7PM.
There really hasn't been anything developing yet, thought there is one shower in Western New York that has popped up, so I am expecting more storms to fire during the next couple of hours. The next SPC outlook will be out by 12:30. It will be interesting to see if they change anything.
There really hasn't been anything developing yet, thought there is one shower in Western New York that has popped up, so I am expecting more storms to fire during the next couple of hours. The next SPC outlook will be out by 12:30. It will be interesting to see if they change anything.
Its going to be close
The severe weather threat is already ending up higher than I anticipated last night. For the second time in a week, the Storm Prediction Center has issued a Moderate Risk area for portions of the Northeast. At this time, we are just to the northwest of this area, with the boundary running from southwest to northeast through about Binghamton. Here are the hail (top) and wind (bottom) outlooks for today from the SPC. The hail one in particular has me concerned, since we are on the edge of the hatched area, which means a 10% or greater chance of hail over 2" in diameter.
8AM Edit: The visible image shows clearing skies behind this morning's area of rain. Since this satellite image was taken before the sun got very high in the sky, the dark area over Western New York is where the sun will be out. That was the key that was going to make or break us: sun. Yesterday, I wasn't calling for much if any sun. But now, things have changed.
I will continue to monitor this situation as it develops. Stay tuned for the latest! The next outlook from the SPC will come around 9:30, so check back closer to 10 for an update.
10AM Update: The newest SPC outlooks remain the same for our area. That keeps us right on the edge of the 30% wind and 30% hail lines, along with the edge of the hatched hail area.
8AM Edit: The visible image shows clearing skies behind this morning's area of rain. Since this satellite image was taken before the sun got very high in the sky, the dark area over Western New York is where the sun will be out. That was the key that was going to make or break us: sun. Yesterday, I wasn't calling for much if any sun. But now, things have changed.
I will continue to monitor this situation as it develops. Stay tuned for the latest! The next outlook from the SPC will come around 9:30, so check back closer to 10 for an update.
10AM Update: The newest SPC outlooks remain the same for our area. That keeps us right on the edge of the 30% wind and 30% hail lines, along with the edge of the hatched hail area.
Tuesday, June 10, 2008
A New Weather Watch
The Storm Prediction Center just issued a Severe Thunderstorm Watch for Central New York and points south until 10 PM. This watch replaces the tornado watch that has been in effect. This doesn't mean the tornado threat is totally gone, however. A lot of the severe weather composite index values that are used to predict severe weather show a semi-tornadic environment overhead. However, wind damage and hail will continue to be the main threats for the rest of the day.
Onto the radar now. As you can see, thunderstorms have again developed to our west into a bit of a broken line. Like this morning, these aren't severe. However, I expect these to strengthen as they head into the more favorable atmosphere sitting over us.
Stay tuned throughout the afternoon and evening as round 2 begins!
Onto the radar now. As you can see, thunderstorms have again developed to our west into a bit of a broken line. Like this morning, these aren't severe. However, I expect these to strengthen as they head into the more favorable atmosphere sitting over us.
Stay tuned throughout the afternoon and evening as round 2 begins!
Not Done Yet
One round of severe storms has exited the region and pressed eastward. This line didn't look like it was going to do much for Tompkins, Cortland and Southern Cayuga counties, but right as it got here, it exploded rapidly. Just shows what a little bit extra heating and humidity can do for storms, as tempertures before the storms had reached into the mid 80's. These storms have caused quite a few hail and wind reports, as expected. Here is the storm report map as of 1:02PM.
Tempertures are back into the low 80's after about a 15 degree drop with those storms. That means we are certainly still have fuel to work with for the rest of the day. Thunderstorms are also now starting to develop well to our west along the cold front in Ohio. They haven't been going for long, but are already looking strong and developing into a line. This is what I have expected to happen, so everything still looks favorable for another, possibly more intense, line of storms later this evening.
In between then and now, additional storms are possible, also with damaging winds and hail. I'll continue to update through the day, so stay tuned!
Tempertures are back into the low 80's after about a 15 degree drop with those storms. That means we are certainly still have fuel to work with for the rest of the day. Thunderstorms are also now starting to develop well to our west along the cold front in Ohio. They haven't been going for long, but are already looking strong and developing into a line. This is what I have expected to happen, so everything still looks favorable for another, possibly more intense, line of storms later this evening.
In between then and now, additional storms are possible, also with damaging winds and hail. I'll continue to update through the day, so stay tuned!
TORNADO WATCH ISSUED
Tompkins County, along with all of Central and Eastern New York is now under a TORNADO WATCH until 6PM tonight!
A little known fact about watches is that they each have probablities of certain severe weather events occuring. For this watch, there is over a 95% chance of 10 or more wind damage reports, as well as over a 95% chance of 10 or more hail reports and a 40% chance of 2 or more tornado reports. That means the main threat is still damaging winds, but tornadoes are becoming an increasing threat.
An update on that line of storms: The northern portion appears to be the stronger part, with numerous warnings now in effect. Stay tuned for more updates on these storms.
Also, the National Weather Service confirmed my belief about multiple lines of storms today when they issued this statement at 10:05AM:
A little known fact about watches is that they each have probablities of certain severe weather events occuring. For this watch, there is over a 95% chance of 10 or more wind damage reports, as well as over a 95% chance of 10 or more hail reports and a 40% chance of 2 or more tornado reports. That means the main threat is still damaging winds, but tornadoes are becoming an increasing threat.
An update on that line of storms: The northern portion appears to be the stronger part, with numerous warnings now in effect. Stay tuned for more updates on these storms.
Also, the National Weather Service confirmed my belief about multiple lines of storms today when they issued this statement at 10:05AM:
... Severe thunderstorms are expected across the region today...
An initial line of thunderstorms will cross The Finger lakes
region... the twin tiers... the Mohawk Valley... and the southern Tug
Hill region this morning... generally between 930 am and 12 noon.
This includes Elmira... Corning... Syracuse... Utica... Binghamton...
and Montrose. Localized strong damaging winds and hail are
possible late this morning.
This afternoon... another round of thunderstorms is anticipated.
Additional lines of storms are expected to cross the area... generally
between 2 and 6 PM. Once again... strong winds and hail are the
primary threats.
Stay tuned to NOAA Weather Radio... or local media outlets... for the
latest updates. Watches and/or warnings may well be issued later
today.
Pre-frontal Storms
The first storms of the day have been ongoing across Western Pennsylvania and Western New York. There have been occasional warnings with these storms, so they have the potential to be severe. However, this isn't the main event today. The cold front still sits way back to the west over Southern Ontario, Western Ohio and Eastern Indiana. On the radar image below, you can see the line of storms along the front begining to form just east of Michigan.
The Storm Prediction Center also updated their outlooks and maps (which I don't have graphics for at this time...). We are still in the moderate risk zone, but the core of it was shifted to the east. All this means to me is the SPC is thinking the line will for a little further east. While I agree with extending the zone further east into Vermont and New England, I am not so sure I agree with cutting the Western Finger Lakes out. We will see.
9:50AM Update: The Storm Prediction Center is now saying they will issue a watch shortly for our area. Stay tunde for updates as the watch is issued!
The Storm Prediction Center also updated their outlooks and maps (which I don't have graphics for at this time...). We are still in the moderate risk zone, but the core of it was shifted to the east. All this means to me is the SPC is thinking the line will for a little further east. While I agree with extending the zone further east into Vermont and New England, I am not so sure I agree with cutting the Western Finger Lakes out. We will see.
9:50AM Update: The Storm Prediction Center is now saying they will issue a watch shortly for our area. Stay tunde for updates as the watch is issued!
MOD. RISK!
A very serious situation is unfolding today for our area, with the Storm Prediction Center placing us under a MODERATE RISK zone. To put this in perspective as to how rare this type of severe weather outlook is for our area, I can only remember 1 other time during the lifetime of grotonweather.com that we have been under a moderate risk, and NEVER have we been under one to start the day! I do have to say, however, that I was thinking last night that this would happen. Here are the areas under the moderate risk (pink in the top image) because of the wind threat (red in the bottom image).
As I have been indicating the past 24 hours, everything is coming together for a major severe weather outbreak. Hot, humid air is and has been in place. This will interact with a cold front and trough of low pressure that will progress eastward through the day. The final piece to the puzzle will be the strong jet stream winds. The thunderstorms that explode later this morning across Western and Central New York will be able to tap into these winds. Winds in some of the storms today could exceed 70, even 80 or 90 mph. The tornado threat is a tad higher than I thought last night as well. I will be updating throughout the day, so make sure to stay tuned here for the most up-to-date, in depth forecasts and outlooks you will find on the web for this area!
(Your normal forecast will be coming by 8AM. To find the forecast, hover over the "Grotonweather" tab in the menu above, then click the "Homepage" link!)
As I have been indicating the past 24 hours, everything is coming together for a major severe weather outbreak. Hot, humid air is and has been in place. This will interact with a cold front and trough of low pressure that will progress eastward through the day. The final piece to the puzzle will be the strong jet stream winds. The thunderstorms that explode later this morning across Western and Central New York will be able to tap into these winds. Winds in some of the storms today could exceed 70, even 80 or 90 mph. The tornado threat is a tad higher than I thought last night as well. I will be updating throughout the day, so make sure to stay tuned here for the most up-to-date, in depth forecasts and outlooks you will find on the web for this area!
(Your normal forecast will be coming by 8AM. To find the forecast, hover over the "Grotonweather" tab in the menu above, then click the "Homepage" link!)
Sunday, June 08, 2008
Round Two Begins!
The clusters of thunderstorms that moved through earlier today have shifted well off to the south and east. While these storms stabilized the atmosphere for a while, in the long run, they only made things worse. Over an inch of rain fell in Groton earlier. Now, with the sun back out, that inch of rain is returning to the atmosphere. Dewpoints have shot up into the mid to upper 70's, making it feel over 90 despite temperatures being in the low to mid 80's. All this moisture is fueling another round of thunderstorms which is just now starting to explode.
Right now, most of these storms are in the southern counties of New York, but there is a large cell over Lake Ontario as well. Further rapid development of storms is certainly possible over the next few hours. There is currently (4:30) a small cell near Trumansburg that will have to be watched for rapid development in the next hour or so. A severe thunderstorm watch remains in effect as well.
Looking into this evening and overnight, there is a very strong line of severe thunderstorms over Michigan right now. These storms have a severe thunderstorm watch for Michigan, and a torando watch issued by the Canadian Weather Service for Southern Ontario. It is hard to say if this line will hold together long enough to effect us, but it is something I will be watching through the evening.
On this radar image (from weathertap.com) you can see the numerous cells firing up in New York, along with the line of storms in Michigan marching eastward.
Right now, most of these storms are in the southern counties of New York, but there is a large cell over Lake Ontario as well. Further rapid development of storms is certainly possible over the next few hours. There is currently (4:30) a small cell near Trumansburg that will have to be watched for rapid development in the next hour or so. A severe thunderstorm watch remains in effect as well.
Looking into this evening and overnight, there is a very strong line of severe thunderstorms over Michigan right now. These storms have a severe thunderstorm watch for Michigan, and a torando watch issued by the Canadian Weather Service for Southern Ontario. It is hard to say if this line will hold together long enough to effect us, but it is something I will be watching through the evening.
On this radar image (from weathertap.com) you can see the numerous cells firing up in New York, along with the line of storms in Michigan marching eastward.
Sunday, June 01, 2008
Storm Reports, May Stats
While there wasn't a whole lot of widespread severe weather yesterday across Central and Western New York, the one area that did seem to get hit hardest was in fact our area. Most of the grotonweather.com forecast range (Tompkins, Cortland and Southern Cayuga Counties) ended up under a severe thunderstorm warning at one point or another as two separate severe storms crossed the area.
The first storm tracked across Southern Tompkins and Cortland Counties in the early afternoon, well ahead of the cold front. This storm produced numerous hail and wind reports, especially once it moved into Broome and Chenango Counties. The second storm came through at about 6pm. This storm took out trees in Cortland and Locke, while hitting West Groton with 3/4" hail, with some smaller hail in Groton.
I have overlayed yesterday's storm reports on Google Earth and marked a few of the towns for reference. The blue circles with a "W" represent a wind damage report, while the green circles with an "H" represent hail. Not a huge outbreak by any means, but considering the lack of severe storms elsewhere, we got hit decently hard.
Onto other things now...did you think May seemed abnormally cold? Well, if you did, you are correct. In fact, the differences between this May and last May are quite staggering. Our average high this May was a very chilly 64.0 degrees. This ended up 12 degrees colder than last May, which averaged 76.1 degrees. In fact, there were only 3 days in which our high this past month reached 76 degrees! (Those days were the 7th at 76, the 26th at 82, and the 31st and 76). Our warmest day this May was 82, much lower than last year's 92 and even lower than 2006's 95 degree day. On the whole, it was the coldest May on my records (2003-present) by three degrees. We also had our coldest nights, with our average lows falling below 40 for the first time.
The first storm tracked across Southern Tompkins and Cortland Counties in the early afternoon, well ahead of the cold front. This storm produced numerous hail and wind reports, especially once it moved into Broome and Chenango Counties. The second storm came through at about 6pm. This storm took out trees in Cortland and Locke, while hitting West Groton with 3/4" hail, with some smaller hail in Groton.
I have overlayed yesterday's storm reports on Google Earth and marked a few of the towns for reference. The blue circles with a "W" represent a wind damage report, while the green circles with an "H" represent hail. Not a huge outbreak by any means, but considering the lack of severe storms elsewhere, we got hit decently hard.
Onto other things now...did you think May seemed abnormally cold? Well, if you did, you are correct. In fact, the differences between this May and last May are quite staggering. Our average high this May was a very chilly 64.0 degrees. This ended up 12 degrees colder than last May, which averaged 76.1 degrees. In fact, there were only 3 days in which our high this past month reached 76 degrees! (Those days were the 7th at 76, the 26th at 82, and the 31st and 76). Our warmest day this May was 82, much lower than last year's 92 and even lower than 2006's 95 degree day. On the whole, it was the coldest May on my records (2003-present) by three degrees. We also had our coldest nights, with our average lows falling below 40 for the first time.
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