Return Of The Tropical WeatherAugust 15th, 2013 at 8:48 am by Jeremy Wheeler under Weather
The title to the blog may sound like a horror movie, but lately lots of folks are dreading any rain returning to the forecast. Luckily we have a few fleeting moments of dryness today across Hampton Roads. There was a nice cold front which moved in a couple of days ago. That brought us the great weather that we had yesterday, last night, and this morning. Notice though that there were some showers and returning moisture across the southern Outer Banks:
The reason for the rain is due to overrunning. I’ve often talked about this in previous blogs. Basically that is when warm/moist air pushes in and flows overtop of a cooler/drier air mass at the surface. The air becomes saturated and this squeezes out some precipitation. That area is probably going to push northward today along with the showers. There is a large stationary front that currently sits from near Bermuda all the way back to south Georgia. This is the dividing line (at the surface) between the dry and moist air. However, aloft the moisture is spreading northward and creating our clouds and N.C. Showers.
So expect scattered showers from Hatteras to Elizabeth City during the day. The dry air could win out for a while and just create some virga. We may see a few spotty showers in the metro by this evening. Then we’ll have scattered rain showers tonight into tomorrow. High temperatures will be nice again today. Highs will be in the upper 70s to near 80 with low humidity. The breeze at the surface will be out of the northeast at 5-15mph. A big slug of tropical moisture is expected to sit over Hampton Roads for the weekend and create scattered to occasional showers for both Saturday and Sunday. Hopefully, the models are wrong about that.
A the moment, the deep tropical moisture stretches even farther south to a weak disturbance in the western Caribbean. This could become another tropical depression or tropical storm in the next day or two. For now it is expected to move west across the Yucatan Peninsula. It won’t have much of a chance to form before moving over land, but it may organize as it comes out over the Gulf of Mexico.
I say another tropical storm because we already have one out there. Sorry I kind of worked backwards today. Tropical storm Erin was newly classified as of 8am EDT this morning. However, it is the farthest feature from us. It is a little south of the Cape Verde Islands which are near Africa. It is on a WNW motion at 16mph. It’s new maximum sustained winds were 40mph. The pressure is still weak at 1006 mb (millibars of pressure).
The global models don’t do much with Erin. That has been happening a lot lately with these westerly moving Atlantic storms. So we’ll see if it follows what happened to Dorian, Chantal, or one of the wannabe storms that tried to form over the last couple of months. It is interesting that the European, GFDL, and LBAR models all take the storm more to the north. The GFS is the one that sends it more to the west as well as the hurricane WRF. The differences are due to how they handle the ridge to the north of the storm. Erin is still way out there. So we have plenty of time to see which model verifies.
Meteorologist: Jeremy Wheeler