Forecast: Potential for strong storms Tuesday

It has been over a week since the area was last plagued by tumultuous weather. Mid to upper 70’s temperatures during the majority of the daytime hours, clear blue skies and light winds have been a staple in the areas weather for the majority of

NAM Model showing the storm system forecast to impact the area on Tuesday, with a powerful mid level trough (left), strong surface low and cold front (center) and potential for heavy rain (right).

the aforementioned stretch of pleasant conditions. Even more impressive is the lack of precipitation — not even isolated showers or thunderstorms have been present since the big cold front with severe thunderstorms crossed the area a few weekends ago. However, the atmosphere is reloading and the potential for a more significant storm will once again rear its head early this coming week. Gulf moisture will surge north ahead of a large upper level trough which is expected to drop south/southeast into the Great Lakes before lifting northeast again into Southeast Canada. However, a strong surface low is forecast to develop over Western New York and drag a cold front from Western Pennsylvania and New York through New England and the Mid-Atlantic states. The cold front will serve as the focal point for the development of heavy rain and thunderstorms.

Storm Prediction Center Day 2 Outlook showing a Slight Risk for severe weather in the Northeast. Categorical (left) and probabilistic (right).

Quite possibly the most interesting development on forecast models, even moreso than the potential for heavy rain, is the magnitude of winds which exist just above the surface. Forecast models are indicating a powerful low level jet (a fast moving ribbon of air in the lower levels of the atmosphere) directly along and head of the cold front…with 50 to 60 knot winds at 900-950mb. Whenever these type of winds exist just above the surface, forecasters look for the potential for thunderstorms and convection to mix them down (as they could potentially cause damaging strong winds if that were to occur). In this situation, the forecast remains somewhat uncertain. The missing piece of the puzzle for a more widespread damaging wind event throughout the Northeast US seems to be the development of instability at the surface to help develop the thunderstorms. Without this, the storms will remain elevated and are much less likely to mix the strong winds down to the surface. Regardless, the Storm Prediction Center has placed our area in a “Slight Risk” for the potential of severe thunderstorms capable of producing damaging winds on Tuesday.

With all of this uncertainty, and talk of potential hazardous weather, it’s certainly important to reiterate that the main story with this storm will be the moderate to heavy rain which will be possible beginning around mid-day on Tuesday and continuing into early Wednesday. The change in weather from the last several days will be quite drastic, with gusty winds even ahead of the cold front and unrelated to thunderstorms. And, as we mentioned above, there is the potential for some hazardous weather (including damaging winds and isolated tornadoes) if some meteorological puzzle pieces fall into place. We’ll be sure to keep you updated with more details as the event draws closer. Remember to follow us on Twitter and Facebook for constant updates.