Area Forecast Discussion
Issued by NWS Wakefield, VA

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KAKQ 170739 AFDAKQ AREA FORECAST DISCUSSION National Weather Service Wakefield VA 339 AM EDT Sun Mar 17 2024 .SYNOPSIS... A weak upper level disturbance crosses the area through this morning. A cold front will drop through the region tonight bringing in cooler air for the start of next week. A stronger cold front will cross the area late Monday into Tuesday morning. && .NEAR TERM /THROUGH TONIGHT/... As of 830 PM EDT Saturday... The latest WX analysis indicates weak sfc high pressure now off the VA/NC coast, with a weak sfc trough along the coast of SC. Aloft, the flow is westerly, with a strong shortwave over the upper midwest, and weaker shortwave energy over the TN Valley, moving towards the southern Appalachians. The sky is still mostly clear across the local area, with a light E-SE flow along the coast, and light/variable to S winds well inland. Temperatures have dropped off fast since sunset, with most areas ranging through the 50s (locally some upper 40s over the typically cooler sections of interior SE VA/NE NC as well as the eastern shore). Models show the weaker shortwave passing through the local area late tonight, which will result in an increase in clouds, especially over the E and SE portions of the FA closer to the sfc low/trough that is progged to move NE along the Carolina coast. In addition, some weak elevated instability (100-300 J/kg MUCAPE and H7-H5 lapse rates of 6.5 to 7C/Km) will briefly overspread coastal VA/NC late tonight as the shortwave passes by. As such, a few showers cannot be ruled out over the Se 1/2 of the CWA between 2-8 AM. Areal average QPFs are only a few hundredths of an inch. Overnight lows will mostly range from the upper 40s to the lower 50s. && .SHORT TERM /MONDAY THROUGH MONDAY NIGHT/... As of 225 PM EDT Saturday... The strong low pressure system tracks east through Quebec Sun into Mon, sending a second, stronger cold front across the area Sun night- Mon. Cloud cover will increase throughout the day ahead of the mainly dry front. However, there may be a little bit of light rain Sunday evening into early Monday as a weak shortwave also moves offshore to our south. Will keep PoPs no higher than 20-30% in SE VA/NE NC with a dry forecast elsewhere. QPFs are a few hundredths of an inch at best. Sunday will be the warmest day of the next several with highs in the upper 60s-lower 70s. Cooler air will begin to filter in behind the boundary, so low temperatures Sunday night will be in the mid-upper 30s to the west and mid to upper 40s to the east/near the coast. Breezy/cooler on Mon with widespread 20-25 mph gusts. Forecast highs are in the mid to upper 50s. A secondary, stronger shot of CAA arrives Monday night-Tuesday morning as the flow aloft becomes NW. Breezy (especially near the coast) Monday night with lows in the upper 20s-30s. Tuesday looks to be the coolest day of the period with continued breezy NW winds (gusts up to 30 mph possible near the coast) and highs in the mid 50s (except for lower 50s on the MD ern shore). && .LONG TERM /TUESDAY THROUGH SATURDAY/... As of 225 PM EDT Saturday... The flow aloft flattens out a little bit from Wed-Thu, but the latest (12z) global models and ensembles still show it remaining WNW. Temperatures moderate into the 60s (with continued dry wx) for Wed, but may cool back down a bit on Thu behind another dry cold front. Still breezy out of the WNW on Wed, with lighter N winds expected on Thu. Then, attention turns to our next low pressure system, which will impact the area sometime between Friday night and Sun/Mon. While there are major differences in the GFS/ECMWF with respect to timing, ensemble mean precipitation amounts are 0.50-1.50" across the FA from Friday (3/22) through Monday (3/25). So, will continue to go with widespread 40-60% PoPs during this time, which will likely need to be raised as confidence in exact timing increases in the coming days (given that ensemble mean QPFs are already > 1"in parts of the area). Temps remain near to below average from Fri through next weekend. && .AVIATION /08Z SUNDAY THROUGH THURSDAY/... As of 220 AM EDT Sunday... Mainly VFR conditions are expected at the TAF sites from early this morning into early Mon morning. However, a shortwave will cross the area through this morning, which may bring a few showers to SBY/PHF/ORF/ECG, with the highest chc being at ECG/ORF. Flight restrictions, mostly from MVFR CIGs are expected for a few hrs across SE VA/NE NC and have included VCSH wording at ORF/ECG. VFR after ~13Z this morning for all areas with winds shifting to the W-WSW and increasing to 10-15 kt (with gusts to 20 kt). Outlook: Isolated to widely sctd showers will be possible over SE terminals (ORF/ECG) with a second, stronger cold front crossing the region tonight into Mon morning (which may result in brief flight restrictions). Otherwise, mainly VFR through the middle of next week. && .MARINE...
-- Changed Discussion --
As of 335 AM EDT Sunday... Latest analysis shows 1012+mb sfc low pressure offshore of the southeast coast early this morning. A potent northern stream ~992mb low pressure system was analyzed over eastern Ontario, with the associated strong surface cold front extending from Lake Ontario SSW into the eastern OH and Lower TN River Valleys. Latest obs and buoy reports showing SSW flow 10-20 kt over the bay, with pressure gradient briefly tightening with weak low pressure sliding across the region this morning. Expect SCA conditions currently in place over the lower James and Ches Bay to quickly ramp down in the wake of this system after 6-7 am, and will therefore extend SCA through 7am for the lower James and lower Bay to match the middle bay zones. Otherwise, no major changes in forecast rationale for today, with winds remaining W-SW 10-15 kt, occasionally gusting to 18-20 kt in the James River and lower bay this afternoon. Winds veer to the N-NW, tonight into early Monday morning, as the pressure gradient tightens once again ahead of the next frontal passage. A brief period of SCA is possible with NW winds over the lower bay. However, SCA headlines are more likely to be needed Monday evening, as a strong cold front drops across the waters. Winds quickly ramp up after 00z/8pm over northern waters, reaching the southern waters by midnight as gusty NW winds bring much cooler air into the region. Wind probs remain low for prolonged gale force gusts (<10%), but quite likely to see solid SCAs appear over the entire area during this timeframe. Cool high pressure builds south of the area Tue night, allowing winds to slowly diminish and SCAs potentially coming down by mid to late Tuesday afternoon. Winds back to the W-SW winds late Tue into Wed, with potential for a brief period of SCA conditions Tue night in the lower bay and lower James River. Another front drops across the area later Wed aftn, pushing winds back to the NNW Wed night and Thu.
-- End Changed Discussion --
&& .AKQ WATCHES/WARNINGS/ADVISORIES... MD...None. NC...None. VA...None. MARINE...Small Craft Advisory until 7 AM EDT this morning for ANZ630- 631. Small Craft Advisory until 4 AM EDT early this morning for ANZ632-634-638. && $$ SYNOPSIS...TMG NEAR TERM...ERI/LKB SHORT TERM...ERI/TMG LONG TERM...ERI/TMG AVIATION...TMG MARINE...MAM/AM

USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.