Friday, December 19, 2008

Dry Slotting

Snow Totals:
10AM- Dusting
11AM- 0.5"
12PM- 1.5"
1PM- 3.2"
2PM- 4.2"
3PM- 4.6"

Bad news for snow totals, good news for traveling...but the storm's dry slot is going to just hit Groton. It is racing eastward across Southern New York and should be entering Tompkins and Cortland Counties by 3:30. This should more or less end the snow.

Now, the low is forecast to start taking more of a southeasterly track, so I think we will get back into the snow this evening. However, we will be hard pressed to get to 8" I think...let alone a foot. I think 5-9" total would be a good projection for Groton now. Areas just to the north, however, that remain in the snow will stick in that 8-14" range.

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.

Thursday, December 18, 2008

Another Friday Snow Storm

Another Friday, another snow storm for Central New York. Unlike last week's storm, this storm is not a nor' easter. It is pretty much moving west to east, so there is no worry about the models having an eastward bias. That makes my life a little easier this time around. I decided to do a snow map after all, even though the entire GrotonWeather forecast area should get the same amount.

As you can see, this will be a big storm, despite its relatively short duration. The snow will being to move in during the morning, before coming heavy by 10 or 11AM. It will really come down hard for a period of 6-8 hours, likely exceeding an inch per hour at times. By the evening, it will quickly taper off to just flurries over night.

I am going to dinner now, but once I get back (by 6:30-7), I will open the chatroom to field questions...and I will likely be there a good part of the night!

Thursday, December 11, 2008

Love That East Bias!

I hinted this morning in my forecast discussion that "If it [the storm] really gets its act together, we could end up on the high end of those totals [from last night's snow map]." Well, the storm remains very impressive on satellite and radar. One thing is very evident though. The eastward bias of the models I was talking about is showing up perhaps even more significantly than I thought it would.

When I looked at the models last night, the back edge of the precipitation was roughly from a Pittsburgh, PA to Rochester, NY line. Already though, precipitation is being detected on radar as far west as Cleveland and Buffalo (though it is probably not yet reaching the ground). The low right now is over northern Georgia and is already a good one hundred or so miles further west than it is supposed to be.

The National Weather Service and local media stations have picked up on this finally and have more or less come into agreement with what I was saying yesterday. Tompkins and Cortland Counties are now under WINTER STORM WARNINGS instead of the Advisories that were in effect. Those last until 10AM tomorrow. Since the low will track a little further inland, the precipitation may be a bit heavier and last a bit longer than last night. I also mentioned this morning the possibility of expanding the 6-10" range west. As you can see, I have now done that with this new data.

After school activities have been canceled for many schools in our area. I would say that the chances of a snow day have increased a bit. It is still far from a certainty, but there is certainly cause for hope!

Also, if you haven't heard yet, I have a new feature on the site that I just added this morning. If you look to the black bar on the right side of the page, you will see a link to the 'GrotonWeather Weather Chat.' The text will either say the chat is open, of that it is closed. If it is open, it means I am sitting in the chat room, ready to give you whatever information you want to know about the weather! So, if you see that the room is open, come on in!

Wednesday, December 10, 2008

Snow Map

11AM Update: I just added a new feature to the website....a chat room! The link to the chat room can be found in the black bar on the right side of the page. More often than not, I will have the chat room closed. But, during times of severe or extreme weather, when I am on my computer forecasting, I will open up the chat for you to ask my questions about the weather. Please click the link to the right for more details...and if the room is open, stop in and say hi!

10:20AM Update:
I have updated the main forecast page as promised. Next blog should be sometime between 4-7PM...probably sooner rather than later!

Original Post:
At last, here is the snow map. When one of the models came in, it still had the storm way east, with Ithaca getting an amazing 0.07" of snow from the storm. That isn't the model I prefer to use on a day to day basis anyways though, so I didn't put too much stock into. The model I do use takes a bit longer to become available (since it goes out a lot longer), so that is why the map has taken so long. That model seems to be settling in nicely with my earlier predictions now.

The temperatures during this storm are going to generally be in the upper 20s to near 30. Since wet snow doesn't accumulate as much as drier snow, I slightly lowered totals from what I pulled out of thin air earlier. As for snow days, at this time, I would probably say its a good idea to expect school on Friday, but someone in the area will likely wake up with a nice surprise three-day weekend.

My next update will likely not be a blog entry, but just my normal morning forecast update. Just click the banner at the very top of the page to see that.

Here we go!

Winter Storm Watches have (finally) been posted for the forecast area! I say finally because, if I had been working at the National Weather Service, I would have issued these watches yesterday. All season long, and going back into last season, the models have shown an eastward biased with storms coming up from the south. This is a large part of why a lot of last winter had a lot of hype about snow storms (myself included), only to have the storms start as snow, then change to ice and/or rain. The actual storm tracks have continuously come further west than the models suggest. So when I saw the models showing snow for Eastern New York and New England yesterday, I thought 'Thats going to hit CNY'....and now, it looks like it will.

The NWS has Winter Storm Warnings up for areas just south and east of us. I again have to say though...they are too far east! Even just a day or so ahead of this event, I do not trust the models to place the heaviest snow properly. So, I am diverging from them and the NWS and, while I haven't checked them, likely the local media as well.

So, what is this all about. An area of low pressure is over the southeast. As I said in this morning's discussion, severe thunderstorms, including torandoes, have been ongoing constantly since yesterday morning. This is indicative of the energy of this storm. As this storm comes up the coast, it will interact with the cold air left over from today's front, with the circulation just pulling more of it in. It will be a classic nor' easter...just not super powerful.

Snow will likely begin to fall in our area sometime in the late afternoon tomorrow and become heavy into the night. This storm will be a pretty quick mover, so that will help in keeping totals down. I also think that, even with the eastward biased, the heaviest snow will stay just east of our area. I haven't had enough time to hammer out a snow map yet, but, on a whim, I am thinking 5-9" is likely for most of Tompkins County and Southern Cayuga County, with perhaps 6-10" over Cortland County.

And now...what you all really want to know....will there be school on Friday? After my epic failing on predicting a snow day last February, I considered not even doing snow days this season...but, due to popular request, I will. Since this storm is coming through at night, I would say there is certainly a chance. Just how much of a chance remains to be seen. You will have to keep checking back to find out!

Next projected update: 10-11:30PM: Snow map!