Key MESSAGE 1, Northerly flow continues today as high builds in, but by Friday SWerly flow will return, bringing hot and humid conditions Friday into the weekend. These conditions will combine to produce uncomfortably warm heat indices with readings in the lower 100s. Heat advisories may be needed Friday into the weekend if this trend holds. Introduced slight chance PoPs Friday afternoon (20%), as SW winds bring enough moisture for PWATs in excess of 1.75" and increased instability ahead of the sea breeze. Saturday moisture build up even more, bringing higher precip chances (30-50%) with the sea breeze and a shortwave at play. Have added CLIMATE section below to advertise Record High temps for FRI and this weekend when heat increases again in the Serly summertime pattern.
KEY MESSAGE 2, Late this weekend a back door cold front approaches the Carolinas as a high builds into the Great Lakes region. Meanwhile, a shortwave approaches the mid Atlantic from the west out ahead of the back door cold front. The shortwave brings precip chances into the region Saturday, with back door cold front bringing some additional forcing Sunday. There are some timing differences with the front, leading to higher uncertainty on timing of precip associated with it. In addition, there are timing and strength differences with the shortwaves out ahead of it. All this means we could see a more active pattern for the weekend, but timings, rainfall totals, and distribution of precip are still unclear.
12z Wednesday through Sunday Cold front is well offshore, with winds becoming light to calm inland. With the generally clear skies and higher low level RHs, patchy fog is possible through the early morning hours. Any fog that develops will quickly dissipate after sunrise with VFR conditions prevailing Wednesday with sct afternoon cu. Winds will be light N to NE shifting to E to SE in the afternoon as the sea breeze pushes inland.
Wednesday night brings another stretch of light to calm winds. We could see some high clouds moving overhead, but if there are enough breaks the calm winds could allow for fog formation. Kept TAFs at 6SM for now, as potential cloud cover keeps confidence low.
Outlook (Wed night through Sat): Pred VFR conditions expected. Mostly dry through Thu with high press over the area. Next precip chance on Fri night into Sat with another system approaching.
Winds and seas are subsiding as front moves further offshore and high starts building in. Winds currently N'rly 15-20 knots and seas 4-6 ft. Sca's should drop off by 9Z, with N'rly winds decreasing to 10-15 knots today becoming E'rly this evening. Winds eventually become SE'rly Thursday and SW'rly Friday. Pinched pressure gradient Saturday brings a risk of SCA conditions to coastal waters, but at this point it is looking marginal, and the forecast calls for SW gusts 20-25 knots.
Outlook (Thu through Sat): S-SW winds return Thu night into Fri though looks to remain below SCA conditions. Pinched pressure gradient Saturday brings a risk of SCA conditions to coastal waters, but at this point it is looking marginal, and the forecast calls for SW gusts 20-25 knots. Gulf stream showers and thunderstorms possible Thursday and Friday mornings with greater chances Sat/Sun with the shortwave and back door cold front.
Nc, none. Marine, none.
