Thunderstorms wreaked havoc in Tompkins County Tuesday night, particularly in the town of Ulysses. To learn more, we turned to our friends at Cornell Weather to help us understand what happened.
This piece was written by Carolina Bieri, a Cornell student in atmospheric science. Click on your question to see your answer.
1 – What caused those storms yesterday?
2 – Why didn’t it seem like there was much warning with these storms?
3 – What kind of damage was reported in the area?
4 – What can I do in the future to be more prepared for severe weather?
1 — What caused those storms yesterday?
A few different factors came together yesterday that resulted in favorable conditions for thunderstorm development. One was the existence of a cold front that moved through the area in the mid-afternoon; showers and thunderstorms developed along this front as it moved east.
Another was the presence of a trough in the upper-level winds, which allowed for warm, moist air from the south to move north into our area. Daytime heating from the sun was also adequate during the early afternoon. This combined with the other two factors led to rapid development of thunderstorms with strong updrafts, resulting in the relatively large hail that was reported.
To be up front about it, meteorologists in the area were not expecting much in the way of severe weather yesterday. Conditions were right for the development of non-severe thunderstorms, but a few other factors necessary for the development of severe weather were not thought to be present, so the overall severe threat was low.
A Flash Flood Warning and Severe Thunderstorm Warning are both in effect for the Ithaca area. Stay indoors until the severe weather passes!
— Cornell Weather (@CornellWeather) August 5, 2014
However, though we try to predict the weather to the best of our abilities (and are almost always able to predict major severe weather outbreaks far in advance), with everyday thunderstorm setups, things simply deviate from our forecasts from time to time. Furthermore, whenever thunderstorms are in the forecast, there is always at least a small chance for the development of severe weather. In this case, thunderstorms developed and ended up having enough “juice” to become severe, even though we weren’t exactly anticipating it.
The National Weather Service was not caught off guard, though; several severe thunderstorm warnings were issued during the mid and late afternoon.
3 — What kind of damage was reported in the area?
According to the Storm Prediction Center’s website (which maintains a database of storm reports for the entire nation) there were several reports of hail in Chemung, Steuben, Schuyler, Tompkins, and Yates counties. All hail reported was larger than one inch, with hail as large as 1.75 inches in diameter reported in Newfield. Heavy rain and flooding was also reported, with 0.71 inches at Ithaca Tompkins Regional Airport (via WeatherUnderground http://www.wunderground.com/cgi-bin/findweather/getForecast?query=Ithaca%2C+NY).
You can find the SPC’s complete listing of yesterday’s storm reports here (http://www.spc.noaa.gov/climo/reports/140805_rpts.html). Keep in mind that these are preliminary reports and are subject to change until confirmed by the National Weather Service in Binghamton.
With the uptick in active weather throughout Upstate New York this summer, it’s important to know what to do in the case of a severe weather event. A NOAA Weather Radio is a great thing to own, as it will let you know of impending severe weather as soon as a watch or warning is issued (listen online here (http://www.wunderground.com/wxradio/) or purchase one from retailers such as Target).
You can also check the SPC’s Convective Outlook (http://www.spc.noaa.gov/products/outlook/) for an idea of the severe weather risk in your community on any given day. When severe weather is happening, make sure you’ve got a safe place to go in your home or nearby. It’s best to pick an interior spot on the lowest floor away from windows (closets and bathrooms work well). If you’ll be spending time outside on a day when severe weather is expected, it’s especially important that you think about where to go in case the weather turns ugly. In addition, don’t attempt to drive through flooded areas; the water is often deeper than you think!
Links to follow for weather updates: