Low pressure is currently developing over East Central Oklahoma. Associated with this area of low pressure is a cold front draped to the south of the system. Meanwhile above the great lakes is another area of low pressure with yet another cold front, this cold front is currently positioned across the upper mid west. That area of low pressure will also continue to move on a west to east position which will have the cold front approaching the region on early friday.
The low pressure over Oklahoma will continue to press off to the east northeast and should move off the coast somewhere around the Delmarva region.
Out ahead of this are of low pressure and its associated cold front is warm, mild air. So as this low pressure heads towards the region its going to cause WARM AIR ADVECTION to occur with a southerly flow. Temperatures are going to warm up into the lower 60s once again. This is going to cause rainfall to break out across the region and to be honest I would not be surprised to hear some general thunder and see some lightning.
Now there has been alot of discussion about what is going to happen with the cold front approaching from the north? Will the cold air make it into the region before the precipitation exits the region? Or will the cold air arrive while the precipitation is still in the region?
First I think its important to realize that out of the model quidance from 00z 3/25 that was available at this writing..the only model that is suggesting that the cold air could effect the precipitation is the NAM. The GFS which was colder and also supporting this same scenario has now come in warmer then what it was previously.
Its also important to remember models and past performance. Yesterday the 24th..the models such as the GFS/NAM were showing high temperatures for yesterday in the 30s at one point behind the front that just came thru recently. Todays high temperature at KABE was 63 degrees. So the models have been overdoing the cold air behind these cold fronts.
Now, this is not to say that the air behind this front will not be colder. But there is a difference between cold enough for snow and colder air.
The other thing to consider is that if there was going to be a rapid drop in temperature behind the front ..I would think we would be seeing something in the way of severe weather Parameters across the region because going from 62 for example to 32 in a 6 hr period would cause some kind of explosive development because of the difference in air masses.
However, we are not seeing that in any of the guidance, and we have not been..at least not across the Northeast region. I think the most realistic approach to take is that the temperatures will gradually drop behind the front and by friday evening into the overnight is when the cold air will be felt and known. By that time , in regards for places like NYC and south precipitation will already be out of the area and skies will have cleared.
Further to the north as the map illustrates there is the chance for that colder air to make it into that part of the region while there is some precipitation around. At the most I think the higher elevations will be looking at is anywhere from a T to 3 inches..Lower elevations i think the temperatures are going to be warm enough to support all rain but it is possible that some areas could see some flakes mixing in.
No comments:
Post a Comment