National Weather Service (2024)

Area Forecast Discussion
Issued by NWS Wakefield, VA

-- Remove Highlighting --

-- Discussion containing changed information from previous version are highlighted. --207FXUS61 KAKQ 261108AFDAKQAREA FORECAST DISCUSSIONNational Weather Service Wakefield VA708 AM EDT Wed Jun 26 2024.SYNOPSIS...High pressure slides farther offshore today. A cold frontapproaches the area later this afternoon and crosses the regiontonight into Thursday, bringing the a chance for showers andthunderstorms. High pressure builds north of the region for thelatter portion of the week.&&.NEAR TERM /THROUGH TONIGHT/...As of 345 AM EDT Wednesday...Key Message:- Heat builds again today and heat indices likely exceed 100F again.- Scattered showers and thunderstorms develop late this afternoon into Wednesday night, with a few storms potentially being strong or severe with damaging wind gusts to primary threat.GOES water vapor channels depict an upper ridge over thecentral CONUS with quasi-zonal flow from the Ohio Valley to theNortheast at the base of a broad trough over the northern GreatLakes. At the surface, high pressure is centered off theCarolina coast and prevails locally. Mostly clear early thismorning with temperatures in the 70s and a SSW wind of 5-10 mph.The trough over the Great Lakes will dig SE today into thisevening pushing a cold front into the Ohio Valley. The low-levelflow increases out of the SW today, allowing 850mb temperaturesto surge to 20-22C ahead of the cold front. This supports hightemperatures in the mid 90s to near 100F. Dewpoints should mixout during the day and drop into the mid to upper 60s (perhapseven a degree or two lower) during peak heating. So whiletemperatures will be near 100F, heat indices will generallyrange from 100-104F. Mostly sunny through mid-afternoon and thenbecoming partly sunny with a SW wind of 10-15 mph.Forecast soundings show that the boundary layer remains cappedmuch of the day prior to some height falls arriving later thisafternoon into tonight. 00z/26 CAMs continue to developscattered tstms in the higher elevations of W/NW VA by 3-4 PMbefore trying to push SE into NW portions of the FA. The highesttstm chances will be from 5 PM-1 AM mainly north of I-64 as theactual front nears the area before the convection graduallyweakens early Thursday morning. Locations south of a Farmville-Richmond-Williamsburg line will likely see little to no rainthrough Thursday morning, with localized totals in excess of 1"possible from Louisa County to the MD Eastern Shore. Inaddition, any storm will be capable of producing damaging windgusts given very strong sfc heating, a deep well mixed boundarylayer, and some mid-level drying. In fact, forecast soundingsfrom most models show DCAPE values of 1200-1500 J/kg Wedaftn/evening. The Day 1 convective outlook from SPC is verysimilar with only a slight nudge southward of the slight andmarginal risk areas. Convection diminishes in coverageovernight. However, some convection will linger overnight withsome instability and the front settling over the area. Lowstonight will mainly be in the upper 60s to mid 70s.&&.SHORT TERM /THURSDAY THROUGH FRIDAY/...As of 345 AM EDT Wednesday...Key Messages:- A few thunderstorms are possible across SE VA/NE NC Thursdayafternoon-evening.The cold front slowly pushes south across southern VA and NE NCThursday as high pressure and a drier airmass build into thenorthern tier of the area. Showers/tstms are expected toredevelop along the boundary Thursday afternoon with the highestchc across SE VA and NE NC. High temperatures return toseasonally hot levels ranging from the mid 80s to near 90F.Shower/tstms largely dissipate or move to our south by lateThursday evening, although some isolated activity could lingerinto the early overnight hours over southern VA. High pressurebuilds across New England Thursday night into Friday followingthe frontal passage. Lows Thursday night fall into the mid60s-lower 70s. Easterly flow Friday will keep highs in the lowerto mid 80s along the coast, and seasonally hot inland withhighs in the upper 80s to around 90F.&&.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...As of 345 AM EDT Wednesday...Key Messages:- Heat rebuilds across the region Saturday and Sunday andpotentially more humid.- Scattered showers and thunderstorms are possible later Sunday afternoon into Sunday night ahead of a cold front.Surface high pressure initially settles off the coast Fridaynight into early Saturday, with some moisture returning as aweak warm front lifts through the area. Therefore, there is aslight chc to low chc of showers and perhaps a tstm from centralVA and the Piedmont to the MD Eastern Shore Friday night intoearly Saturday morning. Lows Friday night are mainly in theupper 60s to mid 70s. Otherwise, the heat builds back over thelocal area this weekend as high pressure settles off theSoutheast coast. Another upper trough and cold front approachthe area from the NW late this weekend, and the cold front isprogged to cross the area Sunday night. Forecast hightemperatures are mainly in the mid 90s on both Saturday andSunday, with aftn dewpoints in the lower to mid 70s (mid 70smainly toward the coast) during peak heating on both days. Thisis supported by the deterministic guidance and MOS guidance, butis below the mid/upper 70s shown by the NBM (which is likelytoo high especially given how dry it has been). Resultant heatindices are in the upper 90s to lower 100s Saturday, and thenpotentially 105-109F for much of the CWA Sunday. Isolated towidely scattered tstms are possible on Saturday afternoon(mainly W of I-95), with a better chc of showers/tstms laterSunday afternoon into Sunday night as the cold front dropsthrough the region. A slight reprieve in the heat is possibleearly next week in the wake of the cold front as the 00z/26 EPSand GEFS each depict below average 850mb temperature anomaliesMonday and Tuesday. However, the ensemble guidance also surgesthe heat back into the region by the middle of next week justprior to Independence Day.&&.AVIATION /11Z WEDNESDAY THROUGH SUNDAY/...
-- Changed Discussion --
As of 705 AM EDT Wednesday...High pressure is centered off the Carolina coast as of 11z.Mainly VFR under some this cirrus with a S to SSW wind of5-10kt. The exception is some patchy IFR stratus around ORFthat should dissipate around 12z. VFR today with SCT aftn CUwith bases of 5-7kft. The wind will be SSW of 8-12kt withoccasional gusts to ~20kt. A cold front approaches from the NWlater this afternoon and drops into the region tonight. There isa 40-60% chc of late aftn/evening showers/tstms for RIC andSBY, with a 15-30% chc of showers/tstms and ORF, PHF, and ECGtonight. A few tstms could produce strong wind gusts along withbrief flight restrictions in heavy rain. Overall coverage ofshowers/tstms diminishes after midnight. The latest guidancedepicts the potential for some stratus late tonight/earlyThursday morning.This front will be slow to push through southern VA and NC NEThursday with a 30-50% chc of redeveloping aftn/early eveningshowers/tstms. High pressure and dry conditions return Fridayinto Saturday. A chance for showers/tstms again later Sunday.
-- End Changed Discussion --&&.MARINE...As of 415 AM EDT Wednesday...High pressure will slide farther out to sea today. Early thismorning, winds were SW 5-15 kt with gusts up to 25 kt in nrnportions of the waters. SCAs remain in effect for the 630/631zns of the Ches Bay until 7 am. SW winds mainly 5-15 kt laterthis morning, will become S and increase to 10-20 kt with gustsup to 25 kt by late this aftn into this evening in advance of acold front. Waves will build to 2-3 ft in the Bay, and seas willbuild to 3-4 ft in the coastal waters. 4-5 ft seas will bepossible for a brief period north of Parramore Island. So, willlikely have SCA conditions again near the mouth of the Bay, andportions of the coastal waters from early this evening to aroundmidnight. That weakening cold front will push through the regionlate tonight into Thu aftn. NE winds expected late Thu nightthrough Fri morning, then E and SE winds for Fri aftn into Satmorning, as high pressure slides by to the north then off thesrn New England coast. Low rip current risk is forecast forall beaches today and Thu.&&.AKQ WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
MD...None.NC...None.VA...None.MARINE...Small Craft Advisory from 5 PM this afternoon to 1 AM EDT Thursday for ANZ634-650-652-654-656.
-- End Changed Discussion --&&$$SYNOPSIS...AJZ/ERINEAR TERM...AJZ/ERISHORT TERM...AJZ/ERILONG TERM...AJZ/ERIAVIATION...AJZMARINE...JDM/TMG