Delayed; Not Denied

I am talking about today’s rain.

It is raining to our south by the MD border, and it will stay that way through early afternoon. A plus for us … dry and cloudy.  By late afternoon the rain will begin to move north and will do so through the night and into Saturday morning. All modeling and forecasts agree with this scenario, however, there is one point I disagree on: amount of rain.

Here is why I think the models and many forecasts are underdone:

1. Front that will lift north as a warm front. This will provide a focus for lift.
2. Deep tropical moisture surging north tonight into tomorrow.  The amount of moisture in the atmosphere from the ground up a few thousand feet into the air, will nearly double by late tonight. When you approach high levels of water in the atmosphere, precipitation rates become efficient.
3. Rain will be moving from the south to the north. This means the ridges around here (align more W-E than N-S) will help squeeze out more rain with additional lifting of the air due to topography.

 
I expect an additional 1.5” – 2.5” of rain by Sat evening. There could still be some more showers or even a rumble of thunder Sat night and Sunday, but the coverage will be decreasing.

Sunday looks decent, but Monday looks better. Sunday could end up 95% dry, and Monday dry through 6 pm, but then the showers and thunderstorm chances increase through Wed morning. But after that … a dry stretch of three days or more could take hold. By then, we will need it.

Due to the clouds and rain today and Saturday will be cool with highs only in the 60’s, but with the passage of the warm front, Sunday highs will reach well into the 70’s to near 80. Monday will be similar, but cooler Tuesday, and Wednesday. A warm up then begins as we head toward Memorial Day weekend.

Until then, enjoy and try not to grow mold on ya!