NY NJ PA Weather Forecasts

The north-central Plains, Mid West, and Great Lakes will be very active today with severe weather.  There are a lot of different mid level disturbances enhancing showers and thunderstorms over the region this morning including a strong MCS over the Dakotas.  However, the overall theme with the severe weather threat through the evening hours will be the digging trough over the Great Lakes over the next 24 hours.  As the trough digs into the region, upper level and mid level winds will increase producing strong vertical directional and speed shear over the region, which will support the development of tornadoes and wind gusts exceeding 60 mph.  Additionally, the combination of warm, moist air at the surface interacting with cold, dry air aloft will lead to severe thunderstorms capable of large hail, especially over eastern South Dakota, eastern Nebraska, and much of Iowa.  

Meanwhile, the approach of Tropical Storm Edouard will also bring the increase potential of severe thunderstorms capable of an isolated tornado, wind gusts exceeding 65 mph, and very heavy downpours.  Significant flash flooding will be possible in some of the strong thunderstorm bands this afternoon.

Additional information can be found at the SPC.

Okay, I admit that I was rather surprised to see Edouard had developed in the Gulf of Mexico yesterday afternoon.  I was even more surprised when I saw the satellite images this morning that had the center completely exposed from the center of circulation.  

However, over the past few hours, Edouard has become a bit better organized as showers and thunderstorms begin to redevelop around the center of circulation.  The showers and thunderstorms were displaced due to northerly wind shear that is now decreasing rapidly.  The ridge over the eastern Gulf of Mexico will build west over the next 24 hours, which will end the shear over Edouard and push the storm to the west towards Houston, Texas.  Edouard will likely remain a tropical storm and at worst reach marginal category 1 hurricane status over the next 24 hours before land fall.  Of course, Edouard will be moving over untapped warm Gulf of Mexico waters, which will feed the storm.  However, the limiting factor for development is time, as Edouard will likely be in land over Texas by this time tomorrow.  

Additional information at the Tropical Weather Page.

As I was discussing in the Technical Forecast Discussion this morning, the trough that is beginning to dig into the Great Lakes today will significantly suppress the heat ridge that is currently building towards the southern Mid Atlantic.  While much of Virginia and Maryland bake in the upper 80’s and lower 90’s with high humidity, much of the forecast area will be spared of the heat.

I always find the progression of model data from the initial idea of how the forecast pattern will play out to what the final conclusion ends up being.  Is the forecast really that much different then what was being shown at this time last week?  

The answer is no.  The overall idea of a digging trough in the Great Lakes and the heat ridge splitting and moving east is right on the dot.  The question, as always, is the magnitude of such an event playing out.  In this case, the trough ended up being stronger than the heat ridge, and thus becomes the dominant player.  This player is going to be rathe pesky as well, as disturbance after disturbance will impact the forecast area through the week producing showers and thunderstorms.

The local forecast and baseball weather pages have just been updated.  I’m working on the technical forecast discussion now.  

One interesting note from the model guidance that I’ll be discussing is the position of the trough between now and August 20th, and how that changing in the trough axis will be very important to the weather conditions for the forecast area.  You know, in some cases, this pattern is going to turn out very much fall like, perfect for post season baseball and early season football!