Thursday, December 06, 2012

Saturday's Warmth -- Reality or Model Hype?

Our cooldown is brief -- moderation in temperatures are taking over starting tomorrow, with a pretty significant warmup *possible* on Saturday.

I say possible because it depends on how dry we get and how quickly showers that are around the region on Friday night into Saturday persist.  Computer modeling suggests that showers will develop along a developing warm front on Friday, lifting north across the region on Friday night as a wave of low pressure develops in the Atlantic and rides up the coast.  Showers, or a period of rain, will persist late Friday night into Saturday morning before they depart.

Computer modeling suggests a very mild Saturday -- temperatures 15 degrees or more above average around the region, which would suggest mid 60's if the Euro computer model is correct.

The NAM is just as aggressive -- suggesting 66 on Saturday afternoon.  Get out your shorts!

The asterisks in this forecast are (1) that rain will have departed the region at some point on Saturday morning -- if it lingers, it will still be mild but we probably will not get as warm as the Euro and NAM are advertising.  Saturday's record of 67 would be flirted with if we get into a decent amount of sun and get the warm front pushed through the region fully.  The other asterisk is that it's December -- home of the lowest sun angles and least amount of daylight.  This means warm air pushes can underperform what models three days out suggest since warm frontal boundaries can be advertised to take a more aggressive push.  Last Sunday's fog and low clouds are evidence of this -- we had a bit of a challenge getting those to burn off locally and temperatures struggled to warm as much as advertised.  Regardless, it will be a pretty mild day as the "cold push" that moved in last night will be short lived.

This isn't to say a warm Saturday won't happen -- lower 60's is a pretty safe bet at this point.  If it looks clearly like the low clouds, rain will excuse themselves in time, don't be surprised to see a warmer reality and don't be surprised if we flirt with a record high on Saturday.