Sunday, September 16, 2012

Tuesday's Wind Threat (Oh, Rain Too)

We are under a slight risk for severe weather on Tuesday, which may end up getting upgraded as we move closer to this next storm system that's poised to move through. While the potential for a soaking is still very much on tap, one of the concerns we have to keep an eye on is for a blast of gusty wind that will accompany the front.

The Storm Prediction Center has us in a 30% risk area for severe on Tuesday evening as low pressure pushes north and northeast through the Great Lakes and intensifies on its trek into New York State.

As the storm intensifies on Tuesday, a robust low and mid level jet could develop along and just east of the low pressure center, which could result in the development of a squall line across the Mid Atlantic and Northeast.  Timing still is uncertain -- the GFS is a bit faster than the other models regarding timing this squall line -- a Tuesday evening passage through the region is what the GFS is predicting...

...while the NAM (below) and Euro are both a bit slower with the frontal passage and the squall line, bringing it through late Tuesday night and early Wednesday.

Both setups bring the potential for severe criteria (58 mph or higher) winds with the front and its associated band of rain and wind.

On paper, this setup is now looking very similar to the one that moved through our region last Saturday but with a bit more moisture associated the front and a bit more robust dynamics.  The heaviest rainfall will still occur to our west -- two inches west of I-81 can't be ruled out, with an inch so for most locations east of I-81 through the New Jersey Turnpike, with lesser amounts at the Shore.  Some localized flooding is possible but modeling has backed off over the last 24 hours on those north/west of the city getting in on two inches of rain...that threat has been pushed farther west.  We'll keep an eye on the rain threat for Tuesday but it seems that this is turning more into a "fall squall" setup and less into a soaking downpour as we approach the event.