Area Forecast Discussion
Issued by NWS Wakefield, VA

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000 FXUS61 KAKQ 191037 AFDAKQ Area Forecast Discussion National Weather Service Wakefield VA 637 AM EDT Wed Sep 19 2018 .SYNOPSIS... High pressure builds into the area Wednesday through Friday. A cold front approaches from the north on Saturday. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... As of 400 AM EDT Wednesday... * NWS Surveys have determined that there have been 6 confirmed tornadoes from yesterday. See PNSAKQ for details. Latest analysis indicates that the sfc cold front is now well offshore of the region. Winds are mainly light out of the N/NW inland, with 10-15 kt winds near the coast. Only a few clouds remain over far SE VA/NE NC, with clear skies elsewhere. Temperatures have fallen into the mid-upper 60s inland with low 70s near the coast. A few obs are showing 1-3SM patchy fog over the western third of the CWA. Expect the patchy fog to continue (mainly over the Piedmont) through the overnight hours before quickly dissipating after sunrise. Despite the frontal passage, temperatures will be quick to rebound on Wednesday (as a secondary push of cooler air remains north of the CWA). Highs will range from the mid-upper 80s, but with slightly less humidity than what we experienced yesterday. Some of the CAM guidance (notably the 19/00z HREF members) is forecasting a few isolated showers to develop this afternoon/early evening over the northwestern counties (on the edge of that secondary push of cooler air). With no discernible forcing mechanism or front nearby, opted to keep PoPs aob 14%. && .SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/... As of 400 AM EDT Wednesday... Dry weather is expected throughout the region from Wed night-Fri. Sfc high pressure centered over northeastern Canada ridges into the region Wed night-Thursday as the secondary push of cooler air arrives. Expect lows in the 60s throughout the bulk of the region on Thursday. Afternoon highs will range from the upper 70s to around 80 on the Lower Eastern Shore, with low-mid 80s expected across the rest of the CWA as a 500hPa anticyclone starts to build back into the region. The ridge of sfc high pressure moves to the south and east of the CWA by Friday as a strong area of sfc low pressure moves into southeastern Canada. This will allow winds to turn back to the south. Forecast highs on Friday are in the mid 80s in most areas (with lower 80s on the Eastern Shore). && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... As of 245 PM EDT Monday... Models show a frontal boundary stalling across the Mid Atlantic region late Sat/Sunday with several waves of low pressure moving east along it through the period. Will carry chc pops each day, trying not to get too fine in timing any wave this far out in time. The boundary will try to sag farther south by Tuesday as high pressure moves across the nern states. Pops a bit lower Tuesday. Highs Sat in the low-mid 80s, mid 70s-mid 80s Sun / Mon, upr 70s-mid 80s Tues. Lows in the 60s to near 70 se. && .AVIATION /12Z WEDNESDAY THROUGH SUNDAY/... As of 630 AM EDT Wednesday... Mainly clear skies across the area this morning, with the exception of some BKN clouds around 6-8k feet over NE NC. Winds are out of the NW at the terminals at 5-10 kt. Expect mostly sunny and dry conditions today, with just FEW-SCT afternoon CU. Winds likely remain aob 12 kt for most of the day and will slowly turn to the N/NE by evening. Cannot rule out a few gusts to 15-20 kt this afternoon (most likely near the coast). VFR conditions likely prevail through most of the 12z TAF period, but there is a chance of some MVFR stratus (mainly near the coast) after 06z tonight as a secondary push of cooler air moves in (with onshore flow). For now, left prevailing VFR conditions in the TAFs with just SCT clouds tonight. Outlook: High pressure settles in through the end of the week with dry weather and mainly VFR conditions. && .MARINE... As of 620 AM EDT Wednesday... Latest marine observations/buoy reports reveal NNW flow across the waters this morning. Surface analysis shows cool front now well offshore of the DelMarVa and the coastal Carolinas. Offshore flow in the wake of the frontal passage have settled down below SCA, after a period of SCA winds earlier this evening in the Bay and lower James. Seas are in the process of similarly diminishing, and average 2-3ft nearshore, ~4ft farther offshore over northern waters. Winds have increased slightly as expected early this morning and should persist through late morning, due to tightening pressure gradient w/high pressure nudging in from the NW. High- res models verifying a bit high this morning, so have kept winds in the Bay just below SCA thresholds, holding at 15 kt...though a few gusts to ~20 kt are possible. NW flow begins to subside into the afternoon, as the high slides closer and gradient begins to slacken slightly. We will have to watch the coastal zones once again for SCA conditions tonight, with building seas as flow turns ENE flow overnight into Thursday. However, w/ sub- sca winds and with NWPS still running a bit higher than Wavewatch, will hold off for now. Any headline for seas over the coastal zones would be short-lived, w/high pressure building over the region for Thu/Fri, then offshore Fri / Fri night. Expect quiet/benign wx during this period with generally lighter winds and seas ~3ft. Next cool front crosses the waters Saturday, with winds becoming WNW post-frontal later Sat into Sunday. There is potential for a brief period of elevated winds in pre-frontal SSW flow early Sat in the Bay/Lower James. && .HYDROLOGY... As of 620 AM EDT Wednesday... River Flood Warnings continue for James River at Richmond Locks and Richmond Westham...the Appomattox River at Mattoax and the Meherrin River at Lawrenceville. Water levels will gradually rise today before cresting and slowly falling late today/tonight through Friday. See FLSAKQ for more site-specific details. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...None. NC...None. VA...None. MARINE...None. && $$ SYNOPSIS...ERI NEAR TERM...ERI/LKB SHORT TERM...ERI LONG TERM...MPR AVIATION...ERI MARINE...MAM/RHR HYDROLOGY... is the U.S. government's official web portal to all federal, state and local government web resources and services.