Rain Wednesday, Flooding Possible. Possible Strong Thunderstorms Wednesday Night

The threat for rain and flooding continues for Wednesday with the arrivial of a strong cold front that will be sweeping through. Add the strong southeast flow tonight into Wednesday and you have ample moisture for a 1.5 to 2.5 inch rainfall and I think everyone is going to be getting this when we add up the totals Thursday morning when its all done and gone. However something caught my eye this afternoon on one of the models that is worth paying attention to and that is what we call the triple point. This is the point where the warm front, cold front and the occulded front meet.

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When I looked a the forecast temperature profiles of the lower part of the atmosphere what struck me were temperatures rising into the 70s over parts of Central and Eastern Long Island which is clues me to the possibility of some strong thunderstorm activity Wednesday night. I have outlined on the map a box area where there is some risk for this but I think based on what the models are showing it could occur north of the black line that I drew.

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The implication of having the triple point coming overhead or nearby is that there could be a cluster of strong thunderstorms that will produce very heavy downpours that could add to the rainlfall in some locations. This is something I want to keep an eye on as we work through the day on Wednesday.

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With regards to Wednesday as of right now there are no flood watches posted for anyone. I think the National Weather Service will wait until Wednesday morning to put up any watches if they are required. Given a couple of inches of rain and leaves beginning to collect all over the place, the possibility of flooding is high in the usual spots that have issues. Along the coast there will be a strengthening southeast to south wind and coupled with with full moon there could be some high tide coastal flooding on the south facing shores of Long Island.

More on all of this later this evening.