Area Forecast Discussion
Issued by NWS Wakefield, VA

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000 FXUS61 KAKQ 280817 AFDAKQ Area Forecast Discussion National Weather Service Wakefield VA 417 AM EDT Sun May 28 2017 .SYNOPSIS... A warm front will lift across the Mid Atlantic this afternoon into tonight. A cold front approaches from the northwest on Memorial Day and stalls north of the region into Tuesday. && .NEAR TERM /THROUGH TONIGHT/... The current surface analysis depicts a weak cold front in vicinity of the VA/NC border as of 08z. The main mid-level shortwave trough that triggered severe tstms yesterday aftn has pushed well offshore. However, some lingering shortwave energy has managed to trigger iso showers/tstms across srn VA over the past few hours. This activity should diminish by sunrise. Temperatures early this morning range from the upper 50s over the MD Ern Shore, to the low/mid 60s into central VA, with upper 60s/near 70 south of the front. Some patchy stratus and/or fog is possible early this morning. This shortwave trough pushes offshore later this morning, with shortwave ridging building over the Mid-Atlantic through midday. The surface cold front remains near the VA/NC border through midday with N/NE flow developing north of the VA/NC border in the wake of the mid-level trough and surface cold front. Cooler over the Ern Shore with highs in the low/mid 70s. Highs generally in the low/mid 80s for central/srn VA and interior NE NC. The surface boundary returns newd into the region later this aftn into the evening and through early overnight hours. This will combine with another shortwave trough resulting in an increasing possibility of showers/tstms approaching from the west during the late aftn and through the evening and early overnight hours. 0-6km bulk shear rapidly increases to 35-45kt after 18z resulting in a chc of a strong to severe tstms once again mainly along and S of the I- 64 corridor. The main threats are damaging wind gusts and large hail. The shortwave trough pushes offshore after 06z, with PoPs rapidly diminishing SW-NE thereafter. Partly to mostly cloudy overnight with lows in the 60s. && .SHORT TERM /MONDAY THROUGH TUESDAY/... A cold front will be crossing the mountains Monday morning, and then continue ewd Monday aftn. Additional showers/tstms are possible Memorial Day aftn/evening. However, the 28/00z model runs are trending drier with less coverage, mainly confined to far SE VA/NE NC, and PoPs have correspondingly been dropped to the 20-30% range. Increasing WSW flow aloft ahead of a trough digging across the Great Lakes will yield 0-6km bulk shear values of 40-50kt. This will combine with ~1000 J/kg of 0-1km MLCAPE resulting in the potential for severe thunderstorms despite limited coverage and mainly across NE NC. Partly sunny on Memorial Day with highs in the low/mid 80s, with the potential for near 90 SE, and 70s along the Atlantic coast of the Ern Shore. Current 00z guidance has trended toward the aforementioned cold front becoming aligned parallel to WSW flow aloft and stalling immediately N of the region to perhaps pushing into the MD Ern Shore. The chc for aftn/evening showers/tstms will diminish Tuesday with low chc PoPs confined to far SE VA/NE NC. Forecast highs Tuesday range from the upper 70s/low 80s to the mid 80s inland W of the Bay, after morning lows in the 60s to low 70s SE. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... The long term period beginning Tuesday night features near normal temperatures and generally low chances for precipitation. Weak and poorly defined frontal boundaries affect the area and confidence in the details of the precipitation forecast are rather low. Thunderstorm chances Wednesday were kept relatively low as weak high pressure builds in. A frontal boundary moves in for Thursday and settles just off the coast Friday and Saturday. Highest POPs (30 to 40 percent) are currently set for southern portions on Friday afternoon and evening. High temperatures are forecast to range from 80 to 85 Wednesday and Thursday and the upper 70s to around 80 Friday and Saturday. Readings will be a bit lower near the coast. Lows are expected to range from 60 to 65. && .AVIATION /08Z SUNDAY THROUGH THURSDAY/... The current surface analysis shows a weak front in vicinity of the VA/NC border, with light N/NE flow north of the boundary and light S/SW flow south of the boundary. Stratus and/or fog is expected to develop near the boundary overnight, with PHF/RIC having the best chc of prevailing IFR conditions, with short- lived IFR conditions possible at ECG. Somewhat drier conditions at ORF/SBY should result in prevailing VFR conditions. Showers/tstms are expected again this aftn/evening as another upper level system interacts with the surface boundary. Sct coverage of showers/tstms is expected after 18z, with more widespread coverage after 21z for central/SE VA/NE NC, and then spreading newd toward SBY after 00z. Strong to severe storms are possible once again with severe wind gusts and hail being the main threats. A minimal chc for aftn/evening showers/tstms will persist Monday through Thursday. Stratus and patchy fog is possible each morning. && .MARINE... Latest surface analysis places a cold front near the Virginia and North Carolina border with high pressure centered off the Northeast coast. The result is onshore flow north of the boundary and south to southwest flow over the North Carolina waters. Speeds are generally at or below 10 knots. Waves generally 1 foot and seas 2 feet. The frontal boundary remains in the vicinity of the North Carolina and Virginia border today as a wave of low pressure pushes offshore late today into tonight. Flow remains onshore at 10-15 knots today, becoming south to southeast this evening, and then west to southwest late tonight. Seas build to 2-3 feet, with waves of 1-2 feet. The front lifts northward Monday as low pressure lifts into eastern Canada. A trailing cold front stalls near the coast Monday afternoon. Model differences with waves of low pressure and the placement of the front/surface trough result in a challenging wind forecast Monday and Monday night, with flow generally west to southwest at or below 10 knots. Waves remain 1-2 feet and seas 2-3 feet. The weak front remains near the coast Tuesday as a stronger cold front approaches from the west. The next front pushes across the waters Tuesday night. A lack of cold advection expected to keep conditions sub-SCA Tuesday night. High pressure builds into the region Wednesday, centering over the waters on Thursday. High pressure slides offshore Friday. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...None. NC...None. VA...None. MARINE...None. && $$ SYNOPSIS...AJZ/JAO NEAR TERM...AJZ SHORT TERM...AJZ LONG TERM...LSA AVIATION...AJZ MARINE...SAM is the U.S. government's official web portal to all federal, state and local government web resources and services.