Area Forecast Discussion
Issued by NWS Raleigh/Durham, NC

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000 FXUS62 KRAH 031941 AFDRAH AREA FORECAST DISCUSSION National Weather Service Raleigh NC 340 PM EDT Wed Jun 3 2020 .SYNOPSIS... Subtropical high pressure near Bermuda will direct hot and humid southwesterly flow across the Southeast for the rest of the week. Afternoon showers and storms are possible Thursday through the weekend with a typical summer-like pattern in place across the region. Slightly lower temperatures are anticipated early next week behind a weak cold front. && .NEAR TERM /THROUGH TONIGHT/... As of 225 PM Wednesday... Early afternoon water vapor imagery depicts quasi-zonal flow from the Great Lakes to the Northeast, with a deepening shortwave trough over the Florida panhandle. A series of troughs embedded in the flow to the north has resulted in some active weather from Wisconsin to New Jersey, and the high level cloudiness across NC earlier today was associated with some of this convection. The high clouds have since moved offshore and aside from some afternoon cu, skies are mostly clear across the central Piedmont. Temperatures have been the main weather story so far with most spots reporting upper 80s so far as of 2 pm. Still looks like lower 90`s is a safe bet by the time all is said and done late this afternoon. Lee troughing east of the mountains will be the focus for showers and storms later this afternoon and evening, although how far east they can make it before dissipating is still up for debate. There is plenty of instability in place across most of the forecast area (MLCAPES in the 1500-2000 J/KG range) but not much in the way of a forcing mechanism to carry the storms too far east of the mountains. 00Z and 12Z HREF along with several recent runs of the HRRR depict most of the activity west of the Triad this evening and this still looks reasonable. One or two of the HREF members hints at a stray shower making its way into the Triad just before midnight and I will stick with the idea of non-zero PoPs in those areas tonight, but elsewhere things should remain dry. Temps tonight will be on the warm side with many spots only dropping into the upper 60s to lower 70s. Increasing cloud cover from the south will also act to keep temps warmer than what was seen this morning. && .SHORT TERM /THURSDAY AND THURSDAY NIGHT/... As of 225 PM Wednesday... The shortwave trough over Florida will gradually make its way northward during the day on Thursday and will aid in the development of showers and storms across the area tomorrow afternoon and evening. Lee troughing east of the mountains should be the initial focus area for storm development, with additional development possible during the evening and overnight hours to the east of I-95 as additional moisture is imported into the area. Thermodynamic parameters are favorable once again during the day on Thursday but the lack of strong steering flow should limit storm durations with multi-cell/pulse the most likely scenario. By the time additional moisture arrives late in the evening, most of the BL instability should be capped and any showers that develop would be tapping into elevated instability with a limited severe threat. Temps on Thursday should be on par with Wednesday, perhaps a few degrees lower given increasing high cloud cover but still at or above normal in the mid/upper 80s. Lows once again in the upper 60s/lower 70s. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... As of 300 PM Wednesday... A broad upper-level trough will move across the Great Lakes Region Friday, then slightly amplify and traverse off the New England Coast by late Saturday. The upper-level trough will remain to our north, but switch southwesterly flow aloft to more northwesterly across the region. A surface trough will remain anchored across the area for the end of the week, helping to maintain moist, southwesterly flow into central NC into the early part of the weekend with dewpoints in the upper 60s to low 70s. Daytime heating will help to generate diurnal showers and thunderstorms, with some showers lingering overnight. Highs Friday and Saturday will be in the upper 80s to near 90, with lows in the mid to upper 60s Friday and in the upper 60s to low 70s Saturday. A backdoor cold front will swing across the region early Sunday, which will shift surface flow more northerly and lower dewpoints into the upper 50s to the north, however the front looks to stall across the southern half of central NC keeping dewpoints in the upper 60s and maintaining a slight chance of showers and thunderstorms Sunday and Monday. The northern Piedmont and Coastal Plain looks dry at this time. By Tuesday, a warm front approaches the region, switching winds from northeast to southeast, and increasing dewpoints into the mid 60s across the region. Diurnal showers and thunderstorms will be more scattered across the region late Tuesday, however a building ridge aloft will likely provide stable conditions to limit the amount of storms. The upper-ridge quickly pushes east Wednesday as an upper-level trough approaches the region. Remnant moisture from Tropical Cyclone Cristobal could interact with the trough, and help increase showers and thunderstorms across central NC late Wednesday. Confidence in timing and precipitation amounts will increase as models align in better agreement. High temperatures early to mid-next week will be near seasonal normals, mostly in the mid-80s, with low temperatures in the upper 60s. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... As of 225 PM Wednesday... VFR conditions expected at all TAF sites through at least Thursday afternoon. Afternoon cu should develop today and diminish after sunset, with increasing high clouds overspreading the area overnight. Thursday will see increasing storm chances but not until after the end of the TAF period. As for winds, most sites are already gusting to around 20 kts. This too will dissipate after sunset and return late tomorrow morning. Outlook: Hot and humid swly flow will result in a chance of mainly afternoon and evening showers and storms and late night-early morning stratus through the weekend. Brief periods of sub-VFR conditions are likely in/around showers and storms but VFR should prevail otherwise. && .RAH WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Leins NEAR TERM...Leins SHORT TERM...Leins LONG TERM...JJT AVIATION...Leins is the U.S. government's official web portal to all federal, state and local government web resources and services.