National Weather Service (2024)

Area Forecast Discussion
Issued by NWS Wakefield, VA

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-- Discussion containing changed information from previous version are highlighted. --258FXUS61 KAKQ 040120AFDAKQAREA FORECAST DISCUSSIONNational Weather Service Wakefield VA920 PM EDT Wed Jul 3 2024.SYNOPSIS...High pressure off the coast gradually settles south into thewestern Atlantic through late this week. Heat and humidity buildover the region from Independence Day through early next week.Daily chances of mainly afternoon and evening showers andthunderstorms also return from Independence Day into theupcoming weekend.&&.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
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As of 920 PM EDT Wednesday...- Key Message: Pleasant and dry conditions continue tonight.GOES water vapor channels depict an upper ridge across the GulfCoast and Southeast this evening, with a trough over the GreatLakes. At the surface, high pressure continues to push off theMid-Atlantic/Northeast coast, with a cold front well to the NWof the region and approaching the Ohio Valley. It is warm and abit more humid this evening with temps in the 70s-lower 80s anddew pts mainly in the 60s. Surface high pressure sinks S offthe coast tonight. Becoming more humid later tonight/towardmorning with overnight lows in the upper 60s to around 70F undera mostly clear sky.
-- End Changed Discussion --&&.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...As of 315 PM EDT Wednesday...Key Messages:- Hot and humid conditions return for Thursday through Saturday.- Rain chances return to the forecast for the afternoon into the evening on Independence Day and again on Friday and Saturday. Best rain chances remain W-NW of the Richmond Metro area into the VA Piedmont.Hotter and more humid conditions will return Independence Daywith increasing SSW flow as the surface high becomes centeredoff the Southeast coast. High temperatures range from the upper80s/lower 90s along the coast, to the mid 90s inland. Continueto undercut the very moist NBM dewpoint numbers, but nonethelessmore humid Thursday, with PWs to climb to ~2.00 by Thursdaynight. Forecast dewpoints in the upper 60s to around 70F duringpeak heating result in heat indices well into the upper 90s tolower 100s.There is a potential for widely scattered showers/tstmsdeveloping along pre-frontal/lee trough Thursday afternoon andevening. Rain chances are generally 20-40% (although 60% for theNW Piedmont) for mainly late aftn/evening tstms (highest PoPsNW of a Farmville- Richmond- Ocean City MD line). A convectiveMarginal Risk remains in place from the SPC for the far NW, withgusty winds from wet microbursts the main hazard. Partlycloudy, warm and muggy/humid Thursday night with lows in thelower to mid 70s.PWs trend up further for Friday, reaching 2-2.25" by Fridaymorning (*near daily max value). Forecast highs Friday aresimilar to Thursday. However, it will be a bit more humid andwith dewpoints slightly higher, heat indices at or above 105Fare likely for central and SE VA and into NE NC. There isanother chance of afternoon showers/tstms Friday along the leetrough lingering over the area. Partly cloudy warm and muggyFriday night with lows in the mid to upper 70s. The weakeningcold front drops into the area Saturday. Once again hot and veryhumid ahead of the boundary with highs in the lower to mid 90sand heat indices of 105-109F possible if not likely. Thisboundary should become the focus for showers/tstms by afternoon.A very moist and unstable airmass will be in place and the500mb flow does increase to 30-35kt across the NW, so somestronger tstms are possible.&&.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...As of 315 PM EDT Wednesday...- Key Message: Heat and humidity linger for Sunday into the first part of next week. Remaining a bit unsettled with a chance for mainly late day and evening showers and storms each day.The upper ridge slowly shifts E off the SE coast while slowlyweakening later this weekend. Meanwhile, an upper trough willremain to our NW over the Great Lakes. The weak cold front fromSaturday may push far enough E Sunday to allow some drier air tofilter in from the NW, with slightly lower chances ofafternoon/evening showers/tstms, and mainly over the SE. Thefront lifts back N and remains in vicinity of the region earlyto the middle of next week with chances of afternoon/eveningshowers/tstms continuing. High will generally be in the upper80s to lower 90s, and locally mid 90s, with heat indices mainly100-105F Sunday through Wednesday. Have remained a little belowthe typical high bias shown by NBM dewpoints, but still expectthem to be back in the low- mid 70s for the period. Nights willbe warm and humid with lows in the 70s.&&.AVIATION /01Z THURSDAY THROUGH MONDAY/...As of 740 PM EDT Wednesday...Prevailing VFR conditions are expected for the next 24 hours.Some very patchy early morning stratus is possible Thursdaymorning. Otherwise, VFR Independence Day with SCT-BKN latemorning to aftn CU with bases of 4-6kft and a SSW wind of8-12kt. A few showers/tstms could drift into RIC after 19-20zand closer to 00z at SBY.Any showers/tstms should dissipate later Thursday evening.There is a potential for early morning shallow ground fog/lowstratus Friday through Sunday mornings with increased low-levelmoisture. This will also lead to a chc for aftn/eveningshowers/tstms as a slow moving boundary approaches from the NWThursday/Friday and gradually weakens as it crosses into theregion over the weekend into Monday.&&.MARINE...As of 220 PM EDT Wednesday...Key messages:- South winds increase to 15-20 kt across the upper Chesapeake Bay tonight with Small Craft Advisories in effect.- Small Craft Advisories are likely to be needed late Thursday afternoon into Thursday evening for the Chesapeake Bay and the Virginia coastal waters.- A period of elevated, diurnally-driven southerly winds is possible Friday and Saturday with Small Craft Advisory conditions possible.High pressure is situated offshore this afternoon, its center to theNE of local waters. High pressure will remain along the coastthrough through tomorrow. A weak front will attempt to pass throughthe area Friday, which will push the high away from the coast. Windstoday are out of the ESE with latest obs reflecting flow of 5-10kt.Over the next few days, winds will follow a diurnal pattern ofbecoming slightly elevated in the evenings and early overnighthours. This evening, SSE winds will pick up to 10-15 in the coastalwaters and rivers, around 15kt in the lower/middle bay, and 15-20 inthe upper bay (which has a SCA for tonight). Tomorrow morning, windsfall back to 10-15 everywhere and turn SSW. The pressure gradienttightens a bit tomorrow evening between the approaching front andthe offshore high. This, combined with sea breeze effects, willallow SSE winds to pick up to 15-20kt in the bay and coastal waters.The rivers/currituck sound look to stay ~10kt in the evening, butcould see potential for a few elevated gusts above 15kt. AdditionalSCAs will likely be need for this time period. Friday follows asimilar pattern as Thurs, except the evening increase looks to behigher in the coastal waters (15-20kt) than in the bay (10-15kt).Similar conditions expected Sat, then lighter winds expected Sunday.Seas this afternoon are 2-3ft, waves are 1-2ft. Seas pick up to 3ftovernight, then increase to 3-4ft Thursday evening through Sat.There is potential for seas ~5ft out near 20nm Fri-Sat, mostly N ofCape Charles. Waves will follow a general pattern of 1-2ft duringthe early morning-early afternoon hours, then increasing to 2-3ft inthe evening hours with the diurnal wind increase.Regarding rip currents, have decided to upgrade the northern beachesto a high rip current risk for tomorrow due to increasing waveheights, longer periods (~12sec), and near shore normal wavedirections. Have maintained the moderate risk for the southernbeaches.&&.CLIMATE...Record High Temperatures for Thu-Sat (July 4-6) 7/4 7/5 7/6RIC 100/2002 102/2012 105/1977ORF 98/1997 98/2012 102/1881SBY 100/1919 102/2012 102/2010ECG 100/1997 100/2012 99/2012Record high minimum temperatures Thu-Sat (July 4-6) 7/4 7/5 7/6RIC 77/1900 79/2012 80/2012ORF 79/2012 80/1999 80/1999SBY 78/2012 81/2012 77/2012ECG 78/2012 77/2018 78/1999&&.AKQ WATCHES/WARNINGS/ADVISORIES...MD...None.NC...None.VA...None.MARINE...Small Craft Advisory until 4 AM EDT Thursday for ANZ630.&&$$SYNOPSIS...AJZ/MAMNEAR TERM...AJZ/ERISHORT TERM...AJZ/MAMLONG TERM...AJZ/MAMAVIATION...AJZ/ERIMARINE...AMCLIMATE...AKQ