Currently: The storm that produced all the bad weather out west is currently over the Missouri Valley. High pressure that has given us decent weather is now off of Cape Cod. Sea breezes have been stronger than guidance has modeled yesterday and today. That is going to be something we need to consider, as long as high pressure systems exit to the northeast, rather than southeast, especially.
Tonight: Guidance is in excellent agreement. When guidance is in such excellent agreement that close in, there generally isn't much of a reason to go against it, and I can't find a compelling reason to do so. Lows should generally be in the mid 40s statewide, with increasing clouds tonight, Some light showers may approach the far SW zones by dawn. A few places along the south coast could be cooler, in the low 40s.
Tomorrow: A "showers" forecast is probably the best way to go, given that this resembles a later season cold front more than anything else. We won't have the severe weather that could be associated with summertime cold fronts, due to the colder temperatures and March sun angle, however. Right now, it appears that showers are possible at any time. However, in general, days like tomorrow generally work out something like scattered showers in the morning. Showers end and the sun comes out. Then we destabilize and get a more solid line of rain with the cold front. There won't be any thunderstorms tomorrow, as CAPE is very low. But there should be a more solid line of showers later in the day. As for temperatures, I will go under guidance for tomorrow's temperatures by 2-4 degrees, as models tend to overestimate warming in these situations early in the season, and guidance has already trended cooler. Also, paying attention to the sea breezes like we've had the last two days, will go with low 50s along the south coast and mid to upper 50s in the interior.
Tomorrow Night/Sat: After the cold front clears the region, the weather will turn much nicer. The NAM and GFS guidance sets are far apart for Saturday's temperatures. Given the fact that we will have fairly strong cold air advection and wind gusts into the 30s at times, I've opted to go close to the NAM guidance, and call for highs to range from the mid 40s in the NW hills, to the upper 40s most elsewhere. A few readings near or just above 50 may be possible in the usual warmest spots.
Long Term: There are two systems of concern in the long term. The first system is Monday. A weak Alberta Clipper system should pass well to our south, taking most of its precipitation with it. However, there is a chance that some of the precipitation associated with it reaches the state, especially along the south coast. Thermal profiles do support snow. However, it is highly likely that if any precipitation does make it this far north with that system that it would be very light. The majority of precipitation associated with this system will also fall during the day. Very light snow, with temperatures a bit above freezing does not tend to accumulate in the third week of March. Therefore, I am not expecting any accumulations with this.
The next system that could affect the state is slated to affect us around Thursday. There are a myriad of solutions still on the table with this, as can be expected this far out. Right now, thermal profiles do support some type of frozen precipitation with this. However, once again, being so far out and being this late in the season, it would take the perfect setup and heavy snow falling to get any kind of decent accumulations, especially if temperatures were marginal and it fell during the day. If the coastal storm system can organize and produce heavy, banded precipitation, then and only then can we start talking about potential accumulations from that storm.
Now for temperatures in the long term... I stayed close to guidance throughout the long term, except went 5 to 7 degrees colder than guidance for Thursday, with the possibility of a stronger storm. Expect high temperatures to range 40-45 on Sunday, mid 40s statewide on Monday, 40-45 on Tuesday, around or just below 50 on Wednesday, and 40-45 on Thursday.
The long range does not look too uncommon for this time of year, seeing the usual war between winter trying to hang on and spring coming. There will be warm periods and cold periods, and an overall stormier than average pattern. However, a lot of guidance hints that troughiness will dominate across the east with transient ridges in between. If you combine this with the sea breeze pattern setting up, it is hard to get too excited about any warm-ups of extended duration.
Now, let's take a look at some of the systems that are slated to affect the area in the coming days in a graphical format. First, let's take a look at the cold frontal passage tomorrow afternoon. This map shows the classic "cold frontal shape" of rainfall along and ahead of the cold front. That's a shape we'll see more frequently as we get into the warmer season.
-GP!