Key MESSAGE 1, A shortwave is swinging through the mid Atlantic this morning and pushing a weak backdoor cool front through ENC until it fizzles out. This brought some light rain to the region last night, with a second wave along the front itself currently moving through the Outer Banks. There has been some lightning observed with this activity, but it has since moved mostly offshore. The weak and elevated nature of the convection rules out any other tstorm associated hazards outside of the occasional lightning strike. Even rainfall rates should be light in nature despite lightning present given how much drier we are near the surface.
KEY MESSAGE 2, Temperatures gradually warm through the weekend. Upper level trough that is currently overhead will gradually push offshore with more zonal flow, albeit above normal heights, setting up across the Eastern Seaboard Sunday into Monday. Dry conditions expected this weekend. Sunday is likely the warmest day, reaching well into the 80s interior zones (70s coast). Did manually bring up temps for NOBX Sunday with SW flow bringing a warmer continental airmass over the NOBX area. Relied more on MOS guidance, going to the mid-upper 70s instead of the upper 60s NBM suggested. Some inland locales could exceed their record temps for the day. A CLIMATE section has been added to the bottom of the AFD. We should effectively mix Sunday as well, with wind gusts near 20mph inland. However, given a more moist SW flow, fire weather concerns should remain rather low Sunday.
KEY MESSAGE 3, Stronger shortwave and deeper upper troughing track across the Northeast and Mid-Atlantic Mon bringing a backdoor cold front quickly through the area. Moisture is lacking with this front, but models did trend upwards with PoPs, so have brought them up from near 20% to near 30% with this update. Instability is negligible due to limited moisture and faster timing of the front keeping thunder chances low. The main sensible weather with this front will be a rapid increase of northerly winds behind it with temps dropping through the afternoon and into evening. If this front were to blow through in the morning, we would have had some fire weather concerns with stronger winds and drier air moving in, but an afternoon progression prevents any fire issues outside of the wind switch.
12z Saturday through Wednesday SCT SHRA and TSRA are moving offshore early this morning, with the risk ending at all TAF sites. In the wake of this activity, BKN mid- level clouds are expected to scatter out this morning, with VFR conditions continuing to prevail. Sw winds will become west, then north, as a weakening cold front moves into the area. Winds may vary in direction quite a bit as the front slows down over the area this afternoon. Eventually, more of a NE to E wind is expected to develop in the wake of the front this evening. Later tonight, increasing mid- level moisture may once again support BKN VFR CIGs (6-9k ft), along with a low-end risk of SHRA and TSRA. It appears the greatest lift and highest TSRA risk will stay just to the SW of ENC, but it is something we'll be monitoring in later TAF issuances. If clouds are not as widespread tonight, there would potentially be a risk of reduced VIS in BR/MIFG.
Early this morning, a period of LLWS impacts is expected to continue through about 12-13z.
Outlook: The next chance of sub-VFR conditions comes Monday as yet another cold front moves through. A TSRA risk may accompany this front as well, but for now the probability of TSRA impacts is <10%. Gusty north to northeast winds (20-25kt) are expected with this front as well.
High pressure shifts further offshore this morning with swrly gradient tightening as a cold front approaches from the north with winds increasing to 15-25 kt and seas building up to 4-7 ft, highest over the warm Gulf waters and Pamlico Sound. Kept the short duration SCA tonight through mid day Monday for the Pamlico Sound and waters south of Oregon Inlet where winds will be strongest. There is lower confidence in Pamlico Sound reaching frequent gusts of 25+ knots, but with the SCA only being in effect for 6 more hours, elected to just keep it in place. Pleasant boating conditions return again Sat night into Sunday as winds then turn swrly on as high pressure weakens over the area.
Outlook: On Monday, SW wind increase with 15-25 kt winds expected, with some 30+ kt possible on the Gulf Stream waters, ahead of approaching cold front. Front passes through Mon afternoon with stout 25-35 kt northerly winds developing in its wake through Mon night into Tue, with seas rapidly building to 6+ ft behind the front later Monday. Gale force gusts not out of the question, particularly on the Gulf waters. Seas will respond to 6-10 ft, highest over the gulf stream waters. Have trended up by about 5 knots with this update, and trends will be worth monitoring for a potential Gale Watch in future updates.
Nc, none. Marine, small craft advisory until 10 am EDT this morning for amz135. Small craft advisory until 2 pm EDT this afternoon for amz152- 154-156-158.
