Currently: "Double barrel" Cold fronts across the Eastern CONUS today- one over NC and one has made it to N FL. Canadian high pressure over Lake Superior. This is why it is so cool, dry, and breezy across the area.
Tonight will be about as good of a radiational cooling night as one can ever expect this time of yr, given how short the nights are. But w/clear skies and lightening winds, we'll radiate very well, esp in the areas that usually radiate well. I have subtracted 3-5 deg off latest guidance. There should be a wide range of temps, from the mid 40s to the low 50s, depending on whether or not your area is typically warmer or cooler at night.
There is still some modest cold air advection tomorrow. In addition, reviewing today's temps at the moment, we are verifying several deg lower than guidance. W/weaker advection tomorrow, I have gone just a couple deg below guidance to compensate. Another winner, w/plenty of sun and highs generally n the mid 70s.
I still think guidance may be trying to warm us up too fast on Fri. The high doesn't really slide offshore and set up return flow until early afternoon, so by then most of the "damage" is already done. So I've stayed a couple deg below guidance. Highs should be near 80, but humidity will increase. Any precip from the approaching front should hold off until very late Fri night, so it will not affect the daytime whatsoever.
Sat is quite a tricky fcst. We have a complex frontal sys to deal with, kind of sim to this past Mon. If you remember, we had warm frontal showers and storms in the morning, and then cold frontal showers and storms later at night. We could repeat that on Sat. Past history can be very instructive when forecasting the future. On Mon, the guidance cleared us out too fast, and as a result, verified several deg too warm. I am not going to go that far below guidance on Sat, but I am going to go a few deg below, because I think a similar scenario could play out. Therefore, I went w/highs in the low 80s. Some locations along the immediate S coast may not make it to 80, esp E of I 91, where clearing could take longer combined with some onshore flow.
Sun should be warm and humid, but when using my 850 temp table, looking at progged 850s and then comparing it to guidance, the overall NBM guidance still looks a couple deg too warm, so I took the under. It will still be warm, w/highs of 80-85.
I may be wrong here, but I went way under temp guidance on Mon. Sure, the air mass is warm, but we have deep-layered S flow, all the way up to 600 MB! This usually would indicate lower temps and higher humidity than guidance wants to indicate. There is also a slight chance of showers and storms Mon, but I kept the chances to just 20% or so. There is no real trigger and the only storms would be created by temp convergence. It still needs to be watched, because those storms can be very slow moving and produce isolated flash flooding. As for temps, look for highs of 80-85, except upper 70s along the S coast.
There will be a much more widespread threat of showers and storms on Tue, and in fact, this could be our best threat for the entire fcst period. A fairly strong cold front approaches into a warm and humid air mass. There is still some Southerly flow around and you never know timing of clouds at this juncture, so I still went quite a bit below guidance. Look for highs in the low 80s, except upper 70s along the S coast.
Next Wed may very well turn out very similar to today, being another Wed. We have very strong cold air advection (at least by late Jun standards), so I took a few deg off guidance to compensate for typical biases at that range. Look for highs mostly in the mid 70s, except a few upper 70s along the I 91 corridor.
Once again, similar to the last fcst package, there are no striking anomalies fcst in the long range. We heat up for a few days, a front goes thru w/t-storms, then we cool for a few days. All in all, the pattern looks to avg out very close to normal.
No graphics today, gotta run! See ya next week!
-GP!