Currently: Complex low pressure system extends from the Upper Great Lakes to Western NYS. A warm front extends ESE out of the WNY low and has just cleared the entire state. Meanwhile, tornado watches were posted in MS and LA this evening. This is the beginning stages of the next system which will affect the state tomorrow- not with tornadoes- but with more rain.
Tonight: Most of the night should be rain-free. The system that brought rain to the area is pulling away and there isn't much behind it. Rain showers are occurring in the NYC metro. Some of these could skim the S coast overnight. As for temps, they really won't fall very much, since we are in the warm sector, and skies really shouldn't clear very much. Lows should range from the low 40s to near 50.
Another concern for tonight will be patchy dense fog, especially along the south coast. With a warm air mass, wet ground, and calm winds, it should be easy for fog to form along the south coast, so use caution if driving.
Tomorrow: The second of these two systems will affect the region tomorrow. This whole system seems to be evolving a bit slower than models were suggesting. I don't think this is really affecting the ultimate evolution of this system. In other words, rainfall totals, temps, etc, will not need to be adjusted. However, we'll just need to push everything back by 2-3 hrs. With this in mind, I'll keep the morning portion of tomorrow's forecast dry, and then get precip in everywhere fairly quickly around lunchtime. It is not entirely out of the realm of possibility for the south coast to get drizzle and fog earlier, given the moisture content of the air mass, but I'm talking about measurable precipitation. Speaking of fog, most fog should clear out by dawn. Any fog that lingers longer will get scoured out by the rain when it moves in. That's the good thing about steadier precip- it absorbs the fog! Temps will be very warm tomorrow, w/highs in the mid 50s, except a few cooler locales in the NW hills.
Tomorrow Night/Thu: Precip will slowly wind down overnight, ending around midnight in the SW, but not until around dawn in the NE. There is a pretty good chance of actually ending November with a bang- literally- and seeing some t-storms tomorrow night between rush hr and just after midnight with the frontal line. After examining soundings and instability parameters, I'll limit the chance of t-storms to roughly west of I 91 and south of I 84. This is where two favorable factors for t-storms exist: warmer temps and better timing. It's normally harder to get t-storms after midnight and even harder to accomplish this in Nov than in the summer! Thu could turn out to be a nice day, as skies clear. Winds will be up on Thu, with gusts possibly getting to 35 MPH or so behind the front. Temps will start out very warm Thu morning, but since we'll be post-frontal and it's the first of Dec, meaning the sun angle is very low, temps will not rise much during the day. Highs should be in the mid to upper 50s, and those could very well be early in the day. Thu's lows will likely be at 11:59 PM or somewhere thereabouts.
Longer Term: The Weekend: The first half of the weekend should definitely be nice and confidence in that is very high. There is a bit less confidence in the 2nd half of the weekend, especially the tail end of the weekend, and not just because it's further out in time, but because there are more modeled system(s) and the models are currently showing very different solutions.
First off, for Fri and Sat, expect sunshine with slightly above normal temps these two days. Puffy cumulus clouds develop each day. There is a small chance of a streamer making it down into the NW hills and dropping a flurry as it passes by Sat afternoon. Temps on Fri should feature lows in the mid 30s and highs around 50 and then lows 30 to 35 with highs in the mid 40s on Sat.
Now for Sunday, I'll keep the day dry for now, as most models hold off any precip until late at night. Temps will be cooler, with lows around 30 and highs 40 to 45. An Alberta Clipper system will pass by Sunday night. This could bring a period of light snow to the state. With marginal sfc temps, most accumulations would be restricted to the NW hills. Accumulations will be light everywhere, with nothing more than an inch, at least based on guidance I am seeing right now.
For Monday and Tuesday: Uncertainty increases as some models move Sun night's clipper slower and phase it with a developing coastal low. This would produce a much more significant storm than what will be shown in the forecast here right now. There would also be precipitation type issues, as at least some of the state would be cold enough for frozen precip some of the time. Other models, like the GFS, keep the two systems separate, which would result in a brush with light snow Sunday night and then a brush with light rain Monday night or early Tuesday, as the system would remain in two pieces and be basically a brush with a clipper and a brush with a coastal in a warmer air mass. For now, I'll take the latter solution, but I have literally no confidence in either solution at this time. The data will still not be onshore for quite a while, so we'll have a while before we iron this out. Temps would also depend on the ultimate evolution of this system, but for now, I'll forecast highs in the mid 40s Monday and maybe a degree or two warmer Tuesday.
Long Range: Players on the field in the long range include a strong ridge somewhere near Alaska and a weaker ridge over Greenland. Those are fairly certain. The uncertainties are where the Alaskan Ridge sets up and how strong the blocking is over Greenland. If the Alaskan Ridge is way to the west, over the Aleutians or the Bering Sea, it might be too far west to bring cold air here. If it's further east, over mainland Alaska or the Yukon Territories, that would deliver big time cold to the area. The strength of the blocking over Greenland may have something to do with all of this, as well. Ensemble members look more like the further east camp with the Alaskan Ridge and do deliver some very cold air to the region, possibly along with winter storm threats by mid-month, so that is the favored solution for now. But keep in mind, a small change in strength and position of the main features could make a big difference in our weather.
Now, let's take a look at our weather graphically, with some maps for your enjoyment! First, we'll look at tomorrow's rain and then we'll look at the "Monday Mess", as I'll call it for now.
This next map, valid Tuesday, shows how one weak system over WV and another clipper over Srn Canada miss each other and never really phase. If the first clipper Sun night would slow down or this Clipper in Srn Canada Tuesday would speed up, they could phase with the coastal low, force it to get stronger and ride up the coast. On this solution, there is no phase, and we don't get much of anything. But other solutions do produce a phase one way or the other.