Flooding Concerns

Over the past few days, a couple of heavy rain events have effected our area. This has left rivers near or just starting to go over their banks and the ground saturated. With another heavy rain event on the way, this is a bit closer look at the potential impacts.

The Advanced Hydrologic Prediction Center puts out river forecasts for the more major rivers. In the Cortland-Southern Cayuga-Tompkins tri-county region, there are three locations that get these forecasts: The Tioughnioga River in Cortland, and Cayuga Lake and Fall Creek in Ithaca. Each location has 4 levels of flooding: action stage, flood stage, moderate stage, and major stage. The action stage is the only one where flooding does not actuall occur. Currently, the two stations in Ithaca are below action stage and are not forecasted to rise to action stage. Our attention then turns to Cortland, where the Tioughnioga is already above flood stage, but is not quite forecasted to get to the moderate stage: (click to enlarge)


Here also is the projected rainfall for Cortland, as forecasted by the NWS: (click to enlarge)


While this rain will certainly swell the Tioughnioga, major flooding problems should be avoided. Now, there are plenty of other small streams and rivers in the area that are swollen. With my resources, I can't tell you which ones will have more flooding problems than others. If you live near a stream, just keep an eye on it, especially tomorrow morning towards the end of the rain. Most importantly though, if you are driving, and you come to a water covered roadway, do not try to drive through it. There is no telling how deep the water is.

Ithaca Ice Jam Location

Noon Update: The Ice Jam has broken up and Fall Creek is back to its normal level. The Flood Warning has been canceled.

This is a map that the Advanced Hydrologic Prediction Service has for the flood gauge that is reporting the ice jam in Ithaca. If you have travel plans in that area, it would be best to find another route!

Groundhog Day Speculation

The meteorological community is abuzz with excitement today. Numerous models are all in agreement with a major storm coming up out of the Gulf of Mexico Monday and then sitting somewhere over the Northeast Tuesday into Wednesday. I thought that with all the hype around this storm already, people might be curious what I think.

First and for most, I will play the broken record and say what I normally do: It is WAY too far out. The models have been showing a storm and are all in pretty good agreement with that, so I do think a storm system will form in the Gulf of Mexico and move north. Beyond that point is where I feel it is too early to place much weight in the models with the track and strength of the storm.

Just to speculate though, here are a couple scenarios that could happen.

The Groundhog Day Blizzard: This scenario would take the low pressure system up the Eastern Seaboard to near New York City, where it would then sit for about 12 hours before heading north. For the first time now in a few years, the atmosphere is getting clogged at the perfect time for a blizzard. The models show an area of low pressure over Greenland, with a strong High over northeastern Canada. This will impede the progress of the coastal storm. This would be the perfect set up for probably the biggest snow storm Central New York has seen in a few years.

The Slop Storm: This scenario would have the storm coming up the Appalachians and either over northeast Pennsylvania and Eastern New York, or right over top of us in the Finger Lakes. This track would give us a mix of precipitation. Some warm air will be in place ahead of this storm, so our precipitation would likely start as either rain, or sleet and freezing rain. As the low tracked towards us, warmer air would come up, and we would go over to rain for a while. Then, as the low moved to our northeast, strong northwest winds would come in and change us back to snow for a moderate snowfall. If I had to guess, I would say this is the most likely scenario at this time. Will it happen? Only time will tell.

February Flooding: The final scenario has the low moving up the west side of the Appalachians. This would pound Ohio with a heavy snow, but for us in Central New York, it would mean a big warm up, probably at least into the 40s, with a soaking rain. Currently there is anywhere from 2 to as much as 10 inches of water equivalent sitting over top of us. That means if all the snow was to melt, that is how much rain it would equal. If even half of that snow pack melted rapidly, plus an inch or more of rain fell, there could be some major flooding problems.

Now, all of these situations focus on the different tracks of the storm. I am cautious right now about the strength of this storm as well, and do not think it will quite be as strong as the models are saying. That being said, the potential for a very memorable, if not historic storm is there. I will be watching this one closely over the weekend and early next week. Keep checking grotonweather.com for more updates!