Key MESSAGE 1, Shortwave and backdoor reinforcing cold front dropping through ENC tonight with moderate low- mid level frontogenesis. The area of enhanced lift associated with the wave and frontal forcing will overlap with an area of moderate moistening and steep lapse rates through late tonight before dry air rushes in. While moisture isn't great, the forcing is enough to squeeze out some sct rain showers falling through a 6-10k ft cloud deck. Very little measurable rain is expected for most areas, and with a drying column commencing pre dawn, showers will quickly erode from NW to SE and off the coast by daybreak.
By sunrise Sat, some areas far inland may still see enough clearing and decoupling winds to get some frost, though temps should remain safely above freezing limiting impacts. The frost adv for the coastal plain counties remains in effect.
KEY MESSAGE 2, A strong surface high will build in over the weekend and will be accompanied by a colder than normal airmass. This should support below to well below normal temperatures, both during the day and at night.
The coldest thicknesses associated with this airmass will settle in late Sat night into Sun morning. With strong high pressure overhead and good radiational cooling conditions, the stage is set for lows in the upper 20s to low 30s for many inland areas away from the influence of water. This includes areas adjacent to Croatan and Hoffman forest, and the freeze watch that was in effect has been upgraded to a freeze warning and expanded to include the interior areas of the Crystal Coast, which typically outpace even the coolest guidance in these very dry airmass regimes. Sun morning may very well end the frost/freeze program for many areas, but for the rest, some frost/freeze potential may continue into early next week as high pressure continues to support good radiational cooling conditions each night in tandem with cont anomalously cold low- level thicknesses and low TD's in place.
KEY MESSAGE 3, The aforementioned very dry airmass and low TD's each day over the coming week will exacerbate the worsening drought conditions in place across ENC, and fortunately winds are not expected to be strong with the high nearby. However, fire weather concerns may grow with the curing vegetation combined with low RH values each afternoon.
12z Saturday through Wednesday High confidence in VFR conditions today with high pressure building in behind the overnight cold front. Main concern for aviation interests today will be gusty NW winds today with increased mixing, peaking at around 20 kt. Clear skies and light and variable winds expected overnight, but airmass will be too dry to support fog.
Outlook (Sun through Wed): Yet another weak front/surface trough is forecast to move through late Sunday into Sunday night with a NW to NNE wind shift. This front isn't forecast to have nearly as much lift or moisture with it, and the risk of SHRA appears much lower. Otherwise, VFR conditions look to prevail into next week with dry airmass in place.
Have inc winds across the marine domain with strong CAA expected tonight into early Sat. 13/12z REFS probs for SCA gusts (>25 kt) are 80-90% for the sounds and Alligator, and with well mixed boundary layer with relatively warm SST's and cold incoming airmass, the strong mixing from aloft will easily allow for wind gusts into the 25-30 kt range overnight into Sat morning. Ocnl gusts to 25 kt are possible at the mouth of the Neuse, though not-ideal fetch from the N to NW will leave out of the SCA suite attm. In addition, have inc seas by several ft for the nrn and ctrl waters due to the N winds being up to several ft too low on NWPS. Used a blend of NBM/WWIV for seas, which will build to 6 ft (nearshore) to 8 ft (offshore) with the strong nrly winds. Sca conditions in effect for the sounds and srn waters through Sat morning, and into Sat evening for the nrn/ctrl waters n of Ocracoke before seas subside below 6 ft.
Outlook (Sun through Wed): High pres will dominate through the period. With low pres trough well offshore and high pres ridging in, general winds will be from the N and NE though speeds should remain sub-SCA levels, with speeds generally 10-20 kt, lower for the inland rivers and sounds. Seas will generally be 2-4ft nearshore, and 3-5ft offshore.
Nc, frost advisory until 8 am EST this morning for ncz029-044-079- 090-091. Freeze warning from 1 am to 9 am EST Sunday for ncz029-044-045- 079-080-090>092-193>195-198-199. Marine, small craft advisory until 9 am EST this morning for amz131- 230. Small craft advisory until noon EST today for amz135-156-158- 231. Small craft advisory until midnight EST tonight for amz150-152- 154.
