Wednesday, March 27, 2013

April 5-7 Potential Nor'easter

The American GFS model is showing a strong storm in the Southeast US on April 5th, in an event that could pose the next threat for a Nor'easter.

The 9 day forecast image of precipitation and mean sea level pressure above has a strong storm system sitting on the Florida/Georgia border. This system is producing widespread and intense precipitation on all sides of the system. The chart indicates its mean sea level pressure is still above 1000 millibars, and while the Gulf of Mexico will be wide open to this system for widespread precipitation, I find it hard to believe that this precipitation will end up as heavy as it is being predicted. The long range American model always has troubles with strength and extent of precipitation in a storm system, and this one is no exception.

Now, the American model proceeds to take this storm out to sea after moving through the Southeast. However, I think there is potential for a Nor'easter to take place rather than the system just moving offshore. Shown above is a forecast chart for 500 millibar anomalies, where warm colors indicate high pressure and cool colors show low pressure. Our storm system is very visible along the Gulf Coast, and it looks like it should go up the coast. However, for some unknown reason, the American model refuses to do so. Considering high pressure over Greenland is strongest to the immediate west of the nation, this storm should have very strong backing to go up the East Coast, possibly producing a strong rain or snow event for many. But neither the American or European models allow this. Based on personal experience, we are almost guaranteed to see this storm's track change, possibly to a position more favorable for sliding up the Eastern Seaboard. There remains a lot to be discovered, but I do believe the potential is there for a Nor'easter.

Andrew

1 comment:

Anonymous said...

Would Chattanooga see this snow?