Key MESSAGE 1, Overall pattern over the next few days will be slightly less conducive for shower and thunderstorm development with high pressure expected to build in behind a passing front today and remaining in control. There is a small threat window around midday into this afternoon, mainly focused south and east of Highway 70 as a cold front crosses the region and interacts with sufficient instability of 1000-2000 J/kg. Some precipitation loading and stronger winds are possible in more organized storms, but otherwise a severe threat is not anticipated. There is also a slight chance on Tuesday as a weak wave of low pressure migrates along the stalled frontal boundary, although guidance has trended slightly drier with this feature.
The next best chance for stronger storms remains Thursday into Friday ahead of a stronger front where deeper shear will likely be present along with strong instability as temperatures soar back into the 90s to near 100 and humidity remains oppressive. Like yesterday, better kinematics and thus higher risk of organized convection will likely be to our north in the mid- Atlantic, but medium-range AI NWP guidance still highlights much of the Carolinas in an elevated severe risk especially on Thursday, and potentially lingering into the day on Friday. The primary threat risk is damaging winds, but other hazards remain on the table.
KEY MESSAGE 2, Behind today's cold front, relatively cooler temperatures will prevail with highs dipping into the upper 80s to low 90s. As alluded earlier, increasing southwesterly flow ahead of the late-week front will boost low-level thicknesses and kick temperatures into the mid to upper 90s by Thursday. Paired with Tds in the low to mid 70s, widespread heat indices of 105-110 are likely. The passing front may cool things down briefly, but long range guidance suggests excessive heat will remain a concern into next week.
06z Monday through Friday VFR conditions in place across majority of terminals this morning with some spotty MVFR and IFR along the Crystal Coast. Precipitation threat has ended for the overnight period, and attention now turns to risk of pre-dawn bank of MVFR to locally IFR low stratus developing, with the strongest signal for OAJ and EWN where heaviest precipitation fell yesterday. An additional window of MVFR is likely after sunrise for a more widespread area as LCLs are slow to lift ahead of the approaching main front with cu fields forming at 2-3 kft.
Shower and thunderstorm threat has trended downwards from yesterday with most likely area of formation east of terminals, developing along the main front in corridor of highest instability. Opted to remove PROB30s from EWN to OAJ based on these trends and carry a dry forecast through the end of the period. Winds gradually veer northwesterly behind the front, gusting up to 15 kt at times, then become light and variable into Tues AM.
Outlook: Iso shower and thunderstorm risk will extend into Tuesday and Wednesday. More widespread convective threat returns Thursday and especially Friday with stronger front. Overnight fog and stratus threat possible each morning.
Regional observations show ongoing SCA conditions across area waters this morning ahead of an approaching front with southwest winds of 15-20 kt and gusts up to 30 kt at times, focused primarily over the Pamlico Sound and offshore waters, where seas have jumped up to 6-7 feet.
Forecast calls for improvement in conditions through the day as front passes over area waters with a shift of winds to the northwest but at a weaker 10-15 kt. Soundside SCA will likely come to an end shortly after sunrise, while offshore conditions should fully improve by sunset.
Passing front today will likely initiate a few showers and thunderstorms, focused across the southern Pamlico Sound and the offshore waters along and south of Ocracoke Inlet.
Outlook (Mon night through Sat): Periodic nocturnal and early morning risk of showers and thunderstorms is possible each weeknight, although most likely odds will be Thursday night into Friday ahead of stronger front approaching area waters. This front will also be the next focus of widespread SCA conditions with a low risk but increasing risk of Gales across the outer waters.
Nc, none. Marine, small craft advisory until 8 am EDT this morning for amz135. Small craft advisory until 5 am EDT early this morning for amz150. Small craft advisory until 11 am EDT this morning for amz152- 154-156-158.
