High pressure will remain in control through the next several days. Dangerous heat will continue today along with the chance for scattered showers and thunderstorms. Typical summertime pattern returns late week and this weekend. Next frontal system approaches the east coast mid next week.
Today As of 625 AM Wed,
Key Messages
- Isolated to scattered severe thunderstorm risk this afternoon and evening
- Dangerous heat will continue today
Latest analysis shows strong ridging at the sfc and aloft this morning, with weak sfc troughing over the coastal plain. Isolated showers and tstms cont over the central waters this morning. There should be more than sufficient time for diurnal destabilization as strong heating quickly ensues in the wake of any morning convection. Heating of a continued moist boundary layer should support MLCAPE climbing to at least 2500-4000 J/kg. Meanwhile, a weak surface boundary is forecast to sag SE into the area as the daily seabreeze develops. Additionally, a weakness is the upper level ridge is forecast to develop, allowing a weak shortwave to move west through ENC. These factors, in addition to increased low-level convergence appears very supportive of scattered deep convection developing by early afternoon. Northeasterly flow aloft should tend to push convection south and west with time, which is more atypical for this area this time of year. Eventually a couple of larger convective complexes may develop, but it looks like this risk will be focused just outside of ENC. Deep layer shear of 20kt or less, and mostly unidirectional hodographs, suggest multicell clusters will develop after a brief window of discrete activity. Given the steep lapse rates and moderate to strong instability, updrafts could be fairly intense, and may be supportive of penny to half- dollar size hail. However, given a lack of better shear, what appears the most likely is the threat for damaging winds. Impressively steep low-level lapse rates of 8-9 C/km and DCAPE of 1500+ j/kg suggests the potential for wind gusts of 60-70+ mph where the most intense cores develop. With time, clustering of storms and strengthening cold pools could enhance this potential. The Storm Prediction Center has all of ENC in a "Marginal" risk, with areas south and west of HWY 70 in a "Slight" risk. With this event, it should be noted that the coverage of thunderstorms isn't expected to be high, but there is some higher-end severe potential given the factors mentioned above.
Convection could impact the temp forecast today, but still looks likely that temps will climb into the mid to upper 90s combined with dewpoints in the 70s to near 80 in spots will likely give way to heat index values peaking at 110-115 deg. The Extreme Heat Warning continues.
Tonight As of 245 AM Wed, Scattered convection will likely be ongoing across the western portions of the forecast area early this evening, gradually tapering off by midnight. Isolated strong to svr tstm threat will continue through late eve. Temps will be slightly cooler than previous nights, with lows falling into the low to upper 70s.
Thursday through Tuesday As of 3 AM Wednesday,
Key Messages
- Hot conditions continue through the long term, with heat indices 100-105F every afternoon (90-100F along the coast)
Low level heights retreat slightly the rest of the week as the upper level ridge weakens, and highs drop to the low to mid 90s, with heat indices 100-105F likely. The cumulative effect of several days with high heat indices (and little relief at night) is something for those working or spending much time outside to consider this week as they make preparations for the heat.
As ridge continues to weaken, trough over central NC and sea breeze will be two areas to watch for thunderstorm development each day. Lack of shear paired with ample instability favors pulse thunderstorms each afternoon/evening. Lack of upper level support keeps PoPs in the slight chance range through Sunday, as coverage of storms will be isolated to scattered. Next week, a frontal system will approach the eastern seaboard. While it is still uncertain if the front will stall to our west or blow through the region, PoPs do trend upwards mid- week.
10z Wednesday through Sunday Through tonight As of 625 AM Wed,
Key Messages - Patchy MVFR fog possible through 12z this morning - TSRA and sub VFR conditions possible this afternoon Upper ridge will begin to breakdown today. This combined with improved lift should lead to a gradual increase in the risk of TSRA, with best chances this afternoon and early evening. Isolated strong storms possible. Patchy fog will be possible again overnight and early Thu morning.
Thursday through Sunday As of 3 AM Wednesday, High pressure overhead helps keep winds light to calm, when paired with moist low levels, may bring sub- VFR conditions each morning.
Through tonight As of 625 AM Wed, Latest obs show light SW-W winds less than 10 kt with seas 1-2 ft. Pleasant boating conditions will continue across the waters through the period. Isolated tstms possible this morning and again this afternoon and evening. Otherwise, outside of thunderstorm activity, boating conditions look to remain good. Of note, where thunderstorms occur, there will be a risk of 40-5kt winds and hail.
Thursday though Sunday As of 3 AM Wednesday, Fantastic boating conditions are expected this week as a ridge of high pressure lingers s over the region. The pressure gradient will remain quite weak, which will allow sea/sound breezes to play a big part in wind strength and direction. Light and variable winds below 10 kts are expected each morning, with winds increasing each afternoon and evening to S/SW 10-15 kts in response to a developing sea breeze. Seas will be mostly 2-3 ft through the weekend.
Nc, extreme heat warning until 8 pm EDT this evening for ncz029- 044>047-079>081-090>092-094-193>196-198-199-203>205. Marine, none.
