For tonight, severe thunderstorms are possible the first half of the night. Please refer to products from the National Weather Service for up to date information. The offices that cover this state are OKX (NYC/LI office) for the southern half, BOX (Boston/SNE) for most of the Northern half, and ALY (Albany/Hudson Valley) for the NW Hills. As far as temperatures, low temps really depend on when skies clear. Since I do not have a ton of confidence either way, I'll split the guidance, and go for lows ranging from the mid 50s to lower 60s.
For tomorrow, we're in between systems. I'll go solidly higher than guidance, since we have a high launch point, and I really don't buy the models that show lots of clouds. Any clouds would be from Dorian, probably be of the high variety, and not arrive until late in the day. So they won't have much of an effect on temperatures. Highs should be in the mid to upper 70s.
Tomorrow Night/Fri: A lot of this forecast depends on the future track of Dorian and also its potential interaction with a trough. There are three distinct scenarios at play here. The first is Dorian passes well east of the area, with no apparent effects at all. For now, that scenario is being dismissed, especially for Eastern CT, since Dorian is growing in size, and for a complete miss, it would have to track well to the east, which does not look plausible right now. The second scenario is Dorian misses east, but a PRE (predecessor rainfall event) sets up and gives the state some rain, possibly heavy East. The final scenario is Dorian fully phases with the trough, strengthening him and pulling him further west, with obviously, much stronger impacts for the entire state. I do not want to really go that route yet, since it would take perfect timing. However, seeing what the latest ECMWF model does really does give me pause (that this could be a viable solution). For now, I'll go with scenario 2 and incorporate a little of Scenario 3, pretty much splitting the difference between the ECMWF and GFS models. This gives the entire state rain later Friday into early Saturday morning, with potentially heavy rain in Eastern CT. I'll also add wind gusts to 40 MPH for Western CT and 50 MPH for Eastern CT for now. It is hard to imagine not needing at least a wind advisory for at least the Eastern third of the state . For temperatures, I'll go a couple degrees below guidance, especially below the GFS, since I think that model is not showing enough rain. Expect high temperatures generally in the upper 60s.
After whatever Dorian does to the state finishes early Saturday, expect a long stretch of nice and calm weather across the state. There are a couple slight chances of precipitation early in the week, as a series of very weak cyclones rotate across the Western Atlc. This could create enough of a marine layer to produce a few periods of light rain or drizzle. But for the moment, chances remain low enough to not include in the forecast.
As for temperatures, for most days in the extended, I stayed fairly close to guidance, with just a tweak here or there. The only exceptions being Monday and Wednesday. I went cooler than guidance both days, in fact, significantly cooler for Wednesday. On these two days, gridded data is showing strong maritime flow, yet the statistical guidance seems to not be picking up on it. So here are the ideas for temperatures in the long term:
Saturday: mid 70s
Sunday: mid 70s, but cooler NW hills and South coast.
Monday: 70 to 75.
Tuesday: mid 70s, but cooler NW hills and south coast.
Wednesday: near 70, except warmer in the I 91 corridor.
In the long range, some of the modeling is hinting at a return to the pattern we've had most of the summer, as fronts buck up against a building Atlc ridge. If that happens, expect a return to warmer and stormier than normal weather, at least for several days.
Now, let's look at some of the systems slated to affect our region in the coming days. First, we'll look at tonight's cold front. Then we'll look at Hurricane Dorian, and what the ECMWF model tries to do with it.
Regarding tonight's cold front, you can see that basically all of New England gets at least some rain. Radar watching will determine who gets the biggest storms.
-GP!