Area Forecast Discussion
Issued by NWS Wakefield, VA

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000 FXUS61 KAKQ 191356 AFDAKQ Area Forecast Discussion National Weather Service Wakefield VA 956 AM EDT Mon Jun 19 2017 .SYNOPSIS... A cold front moves into the the Mid Atlantic region tonight, then stalls across the area through mid week. The boundary dissipates late in the week allowing the Bermuda high to build back in. && .NEAR TERM /UNTIL 6 PM THIS EVENING/...
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Trough aloft continuing gradual amplification through the Great Lakes the rest of today...pushing a cold front closer to the FA from the WNW. PoPs increase WNW (to 60-80%) by late afternoon...while to 20-40% SE. Otherwise...averaging out partly sunny...and remaining very warm/humid. Highs in the u80s-l90s...m80s at the beaches. SPC has outlooked most interior sections in enhanced risk svr...w/ marginal-slgt risk. Core of best uvm/forcing to pass by just N of the FA later today. While plenty of moisture over the local area...slowing push of the front E of the mountains later today may limit coverage or push time of arrival of tstms until closer to 00Z/20. period of any strong/severe tstms (should there be any) would be after 20-22Z (and mainly WNW 1/4-1/2 portion of FA) through the early evening. (Meanwhile...heavy rain likely to become more of a concern by tonight as the front slowly presses SE into the moisture laden air in place). Mention of possible severe stms and heavy rain have addressed the situation in the HWO.
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&& .SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/... Attention then turns to the heavy rainfall potential due to the slow movement of the storms after dark. Corfidi vectors suggest very slow cell movement to the SE along with the potential for training echoes. Thought about a second period flood watch, but confidence not high enough on exactly where the heaviest rain will be given a convective event. QPF amounts avg 1-2 inches with 3+ inches psbl in areas that do get training storms. The rainfall then migrates towards the se areas of the fa after 06Z as the boundary settles across the area. Rainfall intensities begin to drop off later tonight as well. Lows mid 60s NW to mid 70s SE. Frontal boundary progged to stall across sern VA / ne NC Tuesday then sag a bit farther south into NC Wednesday. This will act as a trigger for additional convection to develop. Locally heavy rainfall possible ivof the boundary in the afternoon / evening. Meanwhile, another trof from the north sags south across the region resulting in sct diurnal convection Wednesday. Highest pops across the se. Highs both days in the low-mid 80s (coolest south). Lows Tuesday night in the lwr 60s NW to lwr 70s SE. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... Much uncertainty exists in the long range at this time. Bermuda high pressure remains anchored off the coast through next weekend with moist S-SW flow in place locally. Our weather late next week will be largely dependent on what happens in the GOMEX with regards to any tropical development and whether or not part of that moisture gets pulled northward into our area. Given this uncertainly, will carry above-climo pops Friday through Sunday. Highs through the period will be in the 80s to around 90. Lows in the 60s and 70s. && .AVIATION /14Z MONDAY THROUGH FRIDAY/... ST should dissipate as heating begins this morning. VFR conditions continue into mid afternoon with only SCT-BKN CU expected. Gusty SSW winds between 15-25KTs out ahead of the approaching cold front today. Latest data continues to point to a strong cold front moving slowly se across the region after 00Z. Thunderstorms will likely preceed and accompany this boundary after 21Z. Combo of good model agreement leads to high enough confidence to include thunder in forecast attm. Timing places a line of storms at RIC/SBY between 22Z-04Z, then between 01-04Z across sen TAF sites. Pcpn then translates towards the coast after 06Z with showers through the end of the forecast period. OUTLOOK...The boundary stalls over the area expect scattered afternoon and evening thunderstorms Tuesday and Wednesday mainly southeast portions. There will be a chance for late day tstms across the area on Friday. && .MARINE... Ongoing forecast is on track with SCA flags in effect through this evening for Bay/Sound/Rivers and through Tuesday morning for the coastal waters. A cold front approaches the region from the NW today and pushes into the area late tonight...causing the pressure gradient to tighten up further by this afternoon. Mariners should anticipate S-SW winds 15-25kt (gusts up to 30kt coastal waters) today through tonight. Seas 3-4ft south of Parramore Island this morning will build to 4-5ft by this afternoon. Persistent 4-6ft seas north of Parramore Island today/tonight. Waves on Ches Bay will average 3ft with pockets of 4ft waves possible. The cold front is expected to move over the waters Tuesday morning around daybreak and stall along the Mid Atlantic Coast into Wednesday night; transitioning into a warm front by Thursday morning. SCA conditions to subside by Tuesday morning with SW winds diminishing below 15kt all waters, however SCA flags for coastal waters north of Cape Charles Light will continue through the morning due to seas being slightly slower to subside below 5ft. For Tuesday afternoon through the rest of the week, sub-SCA SW winds will prevail. Seas 2-4ft. Waves 1-3ft. The remnants of subtropical moisture may get pulled into the Mid Atlantic Region on Friday as low pressure tracking across southern Ontario/Quebec drags a cold front through the area. This could result in a tightening pressure gradient and the potential for SCA conditions, however there remains a lot of uncertainty between model solutions at this time. Will monitor trends over the next several days. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...None. NC...None. VA...None. MARINE...Small Craft Advisory until 1 AM EDT Tuesday for ANZ635>637. Small Craft Advisory until 6 AM EDT Tuesday for ANZ630>634-638- 656-658. Small Craft Advisory until 10 AM EDT Tuesday for ANZ654. Small Craft Advisory until 1 PM EDT Tuesday for ANZ650-652. && $$ SYNOPSIS...MPR NEAR TERM...ALB SHORT TERM...ALB/MPR LONG TERM...JDM AVIATION...MPR MARINE...BMD is the U.S. government's official web portal to all federal, state and local government web resources and services.