Area Forecast Discussion
Issued by NWS Wakefield, VA

Current Version | Previous Version | Graphics & Text | 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
-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KAKQ 181751 AFDAKQ Area Forecast Discussion National Weather Service Wakefield VA 151 PM EDT Fri Aug 18 2017 .SYNOPSIS... A warm and humid air mass remains in place across the Mid- Atlantic states today on continued south flow. The next cold front will arrive late tonight and exit the region by Saturday morning. High pressure builds in for Saturday night through early next week. && .NEAR TERM /UNTIL 8 PM THIS EVENING/... Initial showers that developed early this morning are dissipating quickly and the low stratus deck that has been in place for most areas except along coastal areas of the Tidewater and NE NC is quickly dissipating too. As a result the sun will be coming out and temperatures will quickly jump into the upper 80s and continue up into the low 90s for most areas. Ahead of the cold front, seeing lots of clear sky across wrn VA so warming should continue through the afternoon hours. With dewpoints in the mid 70s to around 80 will see heat indices from around 100 to 109 across the area. The highest values will be across SE along the Ches Bay from the Middle Peninsula southward into NE NC. So have issued a heat advisory for that area for the rest of the afternoon. Still looks like afternoon convection will form this afternoon across wrn VA and then head ESE across the region. The 12z NAM is more enhanced with the convection so will need to monitor for possible severe as cape is now forecast to between 3000 - 4000 J/kg. The winds aloft are not extremely strong and the direction shear is minimal. The mostly likely threat would be wind damage from downburst. && .SHORT TERM /8 PM THIS EVENING THROUGH SUNDAY/... The front slowly pushes southeast early Saturday, and models have once again trended a bit faster with the frontal passage, allowing for a quicker end to showers Sat morning. A strong shortwave trough sweeps across the Mid-Atlantic States Saturday night, but it remains north of the area and with the low level moisture gone, not anticipating much except some mid level clouds. By Sunday, high pressure will be over the region with dry and seasonable weather in place. For temperatures, will continue to see near normal weather with highs in the upper 80s to around 90 each day and lows in the low to mid 70s each night except for Saturday night when the drier air will allow temps to drop into the upper 60s to low 70s. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... Sfc high pressure builds north of the area with stacked high pressure residing off the Southeast Coast through Mon night. A thermal trough develops in the lee of the Appalachians for Tue/Tue night, and then a cold front is expected to track through the area on Wed...exiting the coast late Wed night. Conditions will become increasingly more humid with each passing day. Sfc features rather diffuse for Mon, however seabreeze boundaries with the presence of ample moisture will keep a slight chance for showers/storms in the forecast... primarily for the aftn/early evening. Thunderstorm activity expected to become widely scattered Tue as convection develops invof lee trough. The frontal passage Wed/Wed night will provide a better focus for more organized thunderstorms to occur. Highs Mon-Wed generally upper 80s to lower 90s; low-mid 80s beaches. Lows Sun-Tue nights generally 70-75F. Lows Wed night mid-upper 60s NW to 70-75F SE. && .AVIATION /18Z FRIDAY THROUGH WEDNESDAY/... Early morning stratus has burned off with cu developing across much of the region at 18Z. Developing showers/tstms SE of KORF should move offshore before 1830Z, but have included VCSH there in the 18Z-19Z time frame. Radar suggests tstms SE of KECG will remain far enough SE of the terminal to not be an issue, but will continue to closely monitor. A cold front approaching the region this afternoon/evening will initiate shower/tstm development W/NW of the area by 21Z, then moving E/ESE into the region through 03Z. The potential for MVFR/IFR conditions exists as tstms will produce heavy rainfall, but uncertainty of exact timing precludes adding too much specificity to the 18Z TAFs. Have added VCTS to KPHF/KORF since hi-res model guidance suggests decent tstm potential both terminals after 01Z. Expect precipitation to wane after 08Z, leaving generally VFR conditions for the remainder of the TAF period. Outlook: VFR conditions returns later Saturday through the weekend as high pressure builds back into the region. Some early morning fog possible both Sunday and Monday mornings. && .MARINE... Latest sfc analysis shows weak high pressure offshore with a cold front over the OH Valley. This front will track east towards the Mid Atlc today, with southerly flow increasing ahead of the front as the pressure gradient increases. By this aftn/eveng before the fropa conditions will be close to SCA criteria over Bay due to ~15 kt sustained winds and northern cstl wtrs due to 4 ft seas. Not confident enough that SCA conditions will occur to issue headlines attm. The cold front drops into the wtrs tonight, with shras/tstms psbl and winds/waves/seas decreasing thereafter. For Sat, with the front weakening in the vicinity, expect winds aob 10 kt by the aftn with 1-2 ft waves over the Bay and 2-3 ft seas over cstl wtrs. Similar conditions into Sun with little change in the overall pattern. Sub-SCA conditions will continue into early next week with weak sfc high pressure in the area. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...None. NC...Heat Advisory until 8 PM EDT this evening for NCZ013>017- 030>032. VA...Heat Advisory until 8 PM EDT this evening for VAZ084-089-090- 093-095>098-523>525. MARINE...None. && $$ SYNOPSIS...MAM NEAR TERM...ESS/MAM SHORT TERM...ESS/MAM LONG TERM...BMD AVIATION...MAM/WRS MARINE...MAS is the U.S. government's official web portal to all federal, state and local government web resources and services.