Currently: First cold front has moved well offshore. Another cold front was nearing I 90 now and dropping Swd. This front moves thru tonite largely dry, although a brief flurry could accompany it. High pressure then builds in from Canada tomorrow.
Tonight: Since we have that cold frontal passage producing a solid band of clouds, radiational cooling conditions will be less than optimal tonight. Therefore, I stayed pretty close to temp guidance- maybe just tweak down a deg here or there. Lows should mostly be 20-25, except 25-30 in the downtown cities and right alg the SE coast.
Tomorrow: A largely nice, sunny day across the region with less wind than today. Guidance looks good and is generally accepted. I did tweak up a deg here or there, given that snowpack is now dwindling and there will be ample sun. Highs should mostly be in the low 40s.
Tomorrow Night/Sat: A storm system will approach the area. This should be the first in a series of relatively weak waves to affect our area. I have trended the pcpn type to all rain. The Poconos and Catskills will see some snow, but not our hills. The reasoning is that it is a race against time. Cold air is rapidly departing, and CT being further east means a later pcpn start time. So by the time it gets here, it's all rain. Timing of this event looks to be right thru the core of the day- genly from mid morn to mid afternoon, with perhaps some pcpn lingering into the early eve in NE CT. As is my usual convetion during rain events that don't show a huge warm surge, I went 3-5 deg lower than temp guidance. So we're looking at highs genly 40-45- chilly, but not nearly cold enough for snow. Just about all the rain that falls on Sat should be light in intensity.
Long Term (Sun and beyond): For Sun, the 2nd wave in the series will affect the state. Rain from this wave should spread SW to NE during the early afternoon and wrap up by early in the evening. Although this system appears faster, it could pack a bit more of a punch and rain could be moderate at times. As for temps, I went a solid 5 deg below guidance, as NBM guidance does not look to be picking up on low lvl cold very well. So highs should be genly around 40, xcpt maybe some low 40s in the cities and along the S coast.
A third wave in the series affects the state late Sun night into early Mon morn. Rain will again spread SW To NE in the predawn hours and be gone by mid-morning. Guidance is very warm for Mon, but I think guidance tends to clear the skies too fast. There is also strong cold air advection arriving by later in the day. So we'll have a very limited window too warm. Therefore, I subtracted 5-8 deg off guidance and went with highs in the low 40s. Could we spike up for an hr or two? Sure, but that's deceptive anyway, and I want a fcst that reflects reality. In addition, winds will pick up and gust to around 30 MPH during the afternoon Mon, adding to the chill.
The rest of the long term will be pretty quiet, albeit with highly varying temps, which is not too uncommon for this time of yr.
For Tue, a cold shot will affect the state. W/fresh cold air advection, I went a few deg below guidance. Look for highs mostly 30-35, except some mid 30s in the cities along the I 91 corridor, and along the immediate S coast.
Ridging builds overhead on Wed, and temps respond by warming 10 deg from those of Tue. The same temp distribution will also be in place, xcpt the S coast will likely not be quite as warm, since the sound is still very cold.
Thu is probably a couple deg cooler than Wed, as a cool front slips thru Wed nite. There is literally no moisture content with this front, so you'll likely only see some cumulus clouds and a wind shift. Temp distribution across the state looks similar to the past couple days.
The long range looks fairly quiet, although I would not be surprised to see something bigger than what is in today's guidance at some point, due to the large thermal gradient across the CONUS.
I am going to show a few sequential maps today, to detail the evolution of the various weekend waves across the state. It likely does not clear up in between waves and we could see areas of drizzle. All in all, a very gloomy weekend is on the way.
-GP!