Currently: High pressure over NC and VA giving the area nice weather today. A cold front near the Quad Cities moves east tomorrow, bringing a round of showers with it.
Tonight: With increasing clouds and warm air advection, radiational cooling will not be optimum tonight. Therefore, I'll go a degree or two warmer than most guidance. Low temperatures should generally be within a few degrees of 40, but I could see the NW Hills getting into the 30-35 degree range.
Tomorrow: A band of showers will move through the state, in association with an approaching cold front. Although total rainfall amounts will not be all that impressive, the timing of the precipitation is centered around early afternoon. In addition, the precipitation could be briefly heavy before ending. One more note: as the heavier precipitation moves through, temperatures aloft will be rapidly cooling. It will all depend on timing of the colder air plus timing of the precipitation, but it would not be totally out of the question to see a sleet pellet or wet snow flake mix in with the rain before it ends. However, surface temperatures will be well above freezing, so there is no thought at all of accumulations. Speaking of temperatures, they may be a bit tricky, as the air mass is quite warm at first, then the combination of arriving precipitation and a rapidly cooling air mass slams the lid on temperature rises. For the reasons listed above, I'll shave a degree or two off most guidance, and go with highs of 50-55. It could be a case of the high temperature occuring before midday and then a rapid temperature drop thereafter. We could also get a period of wind gusts approaching 35 MPH at and after the frontal passage.
Tomorrow Night/ Saturday: A brief interlude with cooler temperatures. With the combination of clouds arriving and the day beginning with cold air advection on Saturday, I'll go with the cooler (GFS) set of guidance for highs. Highs should be fairly uniform on Saturday, and generally in the mid to upper 40s.
Long Term (Sunday through Thanksgiving Day): A storm system will impact the region on Sunday. Most models track this storm somewhere in the vicinity of Interstate 80. The Northern half of Connecticut could see sleet and especially freezing rain to start through at least part of Sunday morning. Please stay tuned for further updates and exercise caution if this comes to fruition. The timing of this event is from around midnight Saturday night, then ending during the afternoon hours on Sunday. Depending on how long precipitation lingers on Sunday, with cooler air beginning to filter in, some wet snow flakes or sleet pellets could mix in with the rain as the precipitation winds down, generally along and north of I 84. As for temperatures on Sunday, given that these systems typically hold on to cold air much longer than models portray, I am going to go about 5 to 8 degrees colder than guidance on high temperatures. Most of the state should have trouble even making it to 40 degrees!
The rest of the long term looks pretty quiet. A cold front will go through around Thanksgiving day. Right now, it is fairly uncertain as to whether or not there will be any rain with this cold front. However, this cold front is very important in the overall evolution of the pattern, as this will be a catalyst for something of a pattern change back to a much more wintry look.
As far as temperatures through the long term, with the exception of Tuesday, where I went pretty close to the guidance, I generally went 1 to 5 degrees below guidance through the majority of the long term. TI have a variety of reasons for this, but my main reasons are that a) Guidance has verified 3 to 5 degrees too warm at that range, and b ) there are a multitude of weak shortwaves rotating through the area. While none of them will have a major impact on our weather, they will probably produce more clouds than are currently being indicated by guidance. Having said all this, these are the temperatures I expect in the long term beyond Sunday:
Monday: Upper 40s.
Tuesday: Around 50, but a few locations in the I 91 corridor could approach 55
Wednesday: Around 50, but upper 40s in the NW hills
Thanksgiving Day: within a few degrees of 45.
Now, let's take a graphical look at some of the systems slated to affect the region this week. We have two systems in the shorter term, so we'll examine them. First, let's take a look at the frontal passage for tomorrow. As you can see, a good slug of moisture is headed our way, but it isn't going to last very long.