Key MESSAGE 1, Guidance continues high with low level thicknesses later this week, with the warmest temperatures expected Thursday and especially Friday. While temperatures may flirt with records at best, forecast aids and ensemble guidance suggest multiple days of well above normal temperatures. This combined with increasing humidity is forecast to support widespread "feels like" temperatures of 100-105 degrees, with the best chance of reaching records and/or heat indices above 105 on Friday. Additionally, the NWS' experimental Heat Risk guidance shows a moderate to major heat risk for much of ENC from Friday into the weekend. The one caveat (discussed in more detail in KEY MESSAGE 2) is the potential for afternoon showers/storms late in the week as this could provide relief from the heat for some areas each day.
KEY MESSAGE 2, Increasing moisture and instability beneath weakening ridging aloft is expected to support a pattern that is more conducive to a daily risk of convection. Initially this may be mostly seen as a more active seabreeze. However, by the weekend there may be some added large-scale forcing from various upper level impulses forecast to move through, or glance, the region. While the strongest shear looks to be removed from the area, moderate to strong instability may support a daily risk of marginally severe, pulse convection (fairly typical for this time of year).
00z Tuesday through Saturday VFR flight cats across the all of ENC though lower MVFR postfrontal CIGs evident along NOBX and the Crystal Coast. Gustiness has fallen out with sunset, though decent Eerly breeze remains which will continue to ease through the overnight AoB 5kt from 6Z onward. Winds aren't expected to decouple and the dryness of the lower levels are forecast to preclude any fog development over the TAF sites. The one exception would the small pocket of Duplin county that received close to half an inch of rain today, and is one of the sold/sheltered spots. There could be some patchy fog here. Pessimistic guidance shows the pocket of moisture responsible for the MVFR CIGs offshore and along the coast being advected onshore through the overnight by the veering low level winds, but the bulk of available guidance keeps CIGs limited to the upper level cirrus streaming overhead. Have maintained the few- sct MVFR deck as a nod to the possibility, but probability appears low, less than 25%. Tue will have light Eerly winds to start becoming SEerly 7-12kt in the afternoon with clouds aloft and any residual moisture in the lower levels resulting to SCT VFR diurnal clouds.
Outlook (Tuesday through Saturday): High pressure builds into Tuesday with generally low-impact aviation conditions expected. Srly to swrly flow returns with inc moisture and instability within this flow slowly but surely. By Thu there will be small chances (20-30%) of afternoon showers/storms at any given location, esp inland areas along the seabreeze. These may bring brief gusty winds, and tempo reduction in vsby in heavier showers.
A backdoor cold front has passed through with occasional gusts of 20-25kt through early evening. Waters favored in northeast flow (Pamlico Sound, mouth of the Neuse River) appear to have the highest chance to reach 25kt. It looks a bit marginal and brief with the wind gusts of aoa 25kt, so will hold off on SCA issuance attm. Seas of 4-5ft will be common, with some 6-7ft waves possible for the offshore waters with the flow against the Gulf Stream. Winds will diminish to 10-15 kt later tonight, and veer srly to swrly on Tue with speeds remaining in the 10-15 kt range.
Outlook (Tue night through Sat): High pressure continues to dominate. From mid to late week, a strengthening swrly flow is forecast to develop due to the strengthening thermal gradient. A daily risk of 25kt winds appears likely during this time, especially Wednesday and Thursday afternoon and evenings when the thermal gradient is expected to be the strongest.
Nc, none. Marine, none.
