Key MESSAGE 1, As of 9pm, a weakening MCS is currently moving off the coast of NC. The strongest part of this MCS is moving through the Crystal Coast with 30-40mph winds and frequent lightning. Behind this MCS, regional radar shows a MCV moving east through southern VA. While ENC has been worked over from the departing MCS, the risk of isolated to scattered thunderstorms may linger for several more hours until the VA MCV shifts offshore. Any convection overnight should remain sub- severe due to an unfavorable environment.
On Sunday yet another shortwave looks to impact the area ahead of an incoming backdoor cold front. Cams suggest a MCS moving into the region along the shortwave in the evening in addition to any sea breeze convection developing in the afternoon. With better upper level support and more favorable timing compared to todays MCS, this one has a shot at bringing some damaging winds as well. The back door cold front looks to move through overnight Sunday. Precip with the shortwave out ahead of it will likely stabilize up a bit, bringing a lower thunderstorm risk along the front. Spc has us in a marginal (1/5) risk of severe weather Sunday.
KEY MESSAGE 2, A WAA regime will persist through this weekend as high pressure becomes centered offshore. This will bring continued SSW winds and increasing low level thicknesses to ENC. Latest guidance continues to show low level thicknesses generally around 1410-1425m which support highs into the low to mid 90s each day. With temps in the low to mid 90s and dewpoints in the upper 60s to low 70s heat indices will likely peak around 95-103 today and Sunday. Will note, given cloudcover and precip chances both today and tomorrow it looks like we may remain lower than heat advisory criteria so currently not anticipating any heat headlines this weekend. Sunday will see another day of near heat advisory criteria AppTs, 100-105F thanks to the slower progression of the back door cold front. With lows only getting into the 70s each night this weekend there wont be much relief from the heat. If you have any extended plans outdoors this weekend make sure to stay properly hydrated and take proper precautions when outside.
KEY MESSAGE 3, No significant changes to the extended forecast as an omega block sets up across the Eastern CONUS with anomalous ridging persisting across the the midwest and eastern US next week. This will bring the potential for an extended period of dangerous heat to ENC starting around Thurs next week and continuing into the July 4th weekend. Nws probabilistic Heat Risk values of reaching major heat risk levels or higher are currently sitting at about 30-50% on Wed, 60-80% on Thurs, and 80-90% on Fri/Sat which is fairly notable given the higher end values this far out. Those sensitive to heat and anyone planning on spending ample amounts of time outside later next week should continue to monitor the forecast trends as this potential heat wave would have impacts on the holiday weekend.
01z Sunday through Thursday TSRA are quickly shifting offshore this evening, leaving behind a lowered risk through the remainder of the night. The one caveat, though, is an upper level disturbance moving along the VA/NC border. Until this feature moves offshore, there will continue to be a low risk of TSRA. After a brief reprieve, another round of TSRA is expected Sunday into Sunday evening as yet another upper level disturbance moves through. Once again, there will be a risk of 30- 50kt wind gusts with any TSRA that develops on Sunday, as well as brief reductions in VIS to ifr/lifr.
Outlook (Sun night through Thu): Showers and storms could be ongoing in the evening, with periods of sub-VFR. The front will move through Sun night, with conditions improving as N-NE develops. Patchy fog and low stratus will be possible each morning.
As of 9pm, a thunderstorm complex is impacting much of the coastal waters, offshore waters, and the waters near the Crystal Coast. This activity is expected to steadily push east over the next few hours, and will be capable of 30-35kt winds and frequent, deadly lightning. A secondary thunderstorm risk may develop overnight as another upper level wave moves through the area.
The ongoing thunderstorms have disrupted the background southwesterly winds, but these should redevelop overnight. However, the risk of 25kt winds is expected to be low the rest of the night, and the Small Craft Advisory has been cancelled for the Pamlico Sound and the coastal waters north of Cape Hatteras.
Another round of thunderstorms is expected on Sunday. Any storm that develops would bring a threat for locally enhanced winds and seas, as well as frequent and dangerous lightning.
Outlook (Sun night through Wed): Gulf stream showers and thunderstorms possible through Sun evening with the shortwave and back door cold front. Winds will eventually shift from the SW to the NE on Sun night and Mon from N to S behind the aforementioned front. Ne winds then persist behind the cold front Tue into midweek.
Nc, none. Marine, small craft advisory until 5 am EDT Sunday for amz154-156.
