KEY MESSAGE 1, An anomalously strong ridge remain in place over the southeastern CONUS into early next week. This will bring near record temperatures possible for some inland zones during the afternoon today (see Climate Section below). Highs will reach the upper 70s/low 80s generally along and west of US 17, and upper 60s/low 70s closer to the coast. Approaching front Sunday and Monday may keep temps a few deg cooler, but still well above normal. After this front lifts back to the north, potentially even warmer conditions are likely to develop by mid next week ahead of a stronger frontal system Thursday.
KEY MESSAGE 2, A weak front will enter the Carolinas Sunday and linger through Monday, leading to scattered showers and thunderstorms. Modest instability and shear will support the threat for isolated strong to possibly severe thunderstorms Sunday afternoon and evening. Spc has most of the area in a Marginal Svr risk (mainly along and west of Hwy 17). Coverage is expected to be scattered as the line of showers and tstorms enters the CWA, but becomes more widespread once interacting with the sea breeze along hwy 17. For this reason, kept PoPs as likely west of hwy 17, increasing to categorical along and east of hwy 17. Rainfall amounts still do not look to exceed half an inch due to the progressive nature of the line.
KEY MESSAGE 3, A deep neutral to negatively tilted upper trough is modeled to approach the eastern seaboard Thursday as a surface low sweeps through the Great Lakes region. Trailing from this low, a strong cold front moves through ENC Thursday. Ahead of this front, strong southwesterly winds will help bring up moisture, with PWATs modeled to be in the 1.25-1.5" range. While there will be ample forcing, there is still a lot of uncertainty on timing and amount of CAPE available. An earlier progression of the precip (Thursday Morning) would keep instability on the lower end, reducing a severe threat. However, an afternoon progression of the precip would maximize the available instability. This front will be worth monitoring for severe weather concerns as it gets closer. Given the impressive dynamics of this system, elected to not use NBM winds for Thursday as they appear to be much too low. Current forecast has wind gusts around 30 mph inland, 35mph along the coast. Behind the front cool, dry air moves in for Friday.
18z Saturday through Thursday Expect VFR conditions to continue to persist into Sat evening with diurnal sct VFR strato cu through this afternoon and swrly winds 5-15 kt. Tonight, with inc swrly gradient winds, fog will not be a concern, though IFR to MVFR stratus looks like a good possibility, with probabilities for IFR stratus of 60-80% late tonight, generally after 08Z. For this reason, have a prevailing IFR deck developing after 08Z for all terminals. Low stratus will mix out after 14Z Sun. Showers with sct thunderstorms develop on Sunday afternoon into early evening as a cold front approaches.
Outlook, Monday through Thursday: Once this front pushes through the area it will likely stall near the region continuing to bring chances for sub-VFR conditions to ENC Mon and Tue before widespread VFR conditions officially return on Wed.
Latest obs show south to southwest winds at 10-15 kt or less with seas 2-4 ft with high pressure offshore. Pleasant boating conditions will continue today with SSW winds increasing to 10-20 kt tonight. Sw winds will mix well over the warmer central waters late tonight, increasing to 15-20 kt gusting to 25-30 kt with seas building locally up to 6-7 ft. Expanded the SCA to southern waters as well with this update, with satellite imagery indicating warm gulf stream waters encroaching into our southern marine zones. These warm waters will help mix down stronger wind gusts.
Minor sea fog persists along some of our waters early this afternoon. However, it is not expected to be widespread or dense enough for a Marine Dense Fog Advisory. Tonight, we could see another round of sea fog, although strengthening SW winds may work against dense fog formation.
Outlook: SCA conditions likely to continue for the central waters through Sunday night for gusts to 25 kt and seas around 6 ft. A stronger front will likely cross the waters Thursday. Sw winds will strengthen ahead of the front Wed and Wed night with SCA conditions likely.
Nc, none. Marine, small craft advisory from 1 am Sunday to 4 am EST Monday for amz152-154. Small craft advisory from 8 am Sunday to 2 am EST Monday for amz156-158.
