Storm Finally Lifts Out

Wednesday June 24, 2009 05:54 AM

Thursday AM Update: Well the worst of the misery is behind us. That's the good news. The bad news is it's a slow recovery back to normal. The storm system that has plagued the region all week is still sitting over the region but is rapidly filling in and weakening. Consequently, the brisk onshore flow and persistent rain and drizzle is over. Now we just need to see some sunshine!

With winds taking on a slightly more offshore component today and the thickness of the cloud deck lessening, the gray overcast we have been greeted with Thursday morning should slowly burn off and thin out over the course of the day today. This will allow for some partial sunshine to develop later today, boosting temperatures into the lower 70s.

While the extended forecast features numerous chances for showers and/or thunderstorms, the overall theme is for gradual improvement in the coming days. 

Wednesday's Forecast: A weather pattern more reminiscent of early April has dominated our weather for much of the month of June. Temperatures are running between 2 and 3 degrees below normal for this month.

The culprit: An unusually amplified and active polar jet stream has been displaced further south than usual, allowing cooler than normal, and rather unsettled, weather to persist over New England. This pattern culminated this week with a large and rather strong coastal storm.

At the jet stream level, this storm became so amplified that it was cut-off from the main steering flow, as it evolved into a closed, stationary upper level low pressure system, with a strong surface reflection. "Cuf-off lows" are notorious for delivering long-stretches of dreary weather, especially during the early spring months.

Looking at the long-wave pattern for the coming week to 10 days, the polar jet looks to remain rather active and far south. However, it does appear that the worst of the weather is behind us and a somewhat more traditional late-June weather pattern will gradually evolve.

Today's Maps & Charts image is a look at a 500 mb (about 18,000 feet up) weather chart from the GFS computer model. The top graphic is the initial conditions from early Wednesday morning. Notice the closed, counter clockwise loop near Cape Cod - indicative of the stationary low pressure system. The bottom image is 48 hours from now, or Friday morning. It is easy to see that the upper level storm has finally departed and a more normal westerly wind flow is in place. Could some summer-like weather finally be knocking on our doorstep?