007 FXUS61 KAKQ 111606 AFDAKQ Area Forecast Discussion National Weather Service Wakefield VA 1206 PM EDT Thu Oct 11 2018 .SYNOPSIS... A cold front approaches from the west today, as tropical cyclone Michael moves northeast across the southeast states and through the Carolinas. The storm will then track off the Mid Atlantic coast and out to sea Friday morning. Please refer to forecasts from the National Hurricane Center regarding Michael. && .NEAR TERM /THROUGH TONIGHT/... As of 930 AM EDT Thursday... Spoke to soon. Tornado watch out through 9 PM. Latest MSAS has TS Michael centered NNW of CAE, moving NE at 21 mph with its pcpn shield advancing NE into NC. Ahead of it, some heating occuring east of I95 helping to enhance the instability. SPC has upgraded the srn half of the fa to enhanced risk with a buffer area of slght risk around it. The main threat is for some spin-up tornadoes that may develop in any tstrm ahead of the pcpn shield given the favorable wind shear profiles. The main threat later today is the heavy rainfall associated with Michael's circulation after 21Z. Not much change to the grids (main changed was to increase the threat of tstrms) based on latest data. Based on PW's, expect a widespread moderate to heavy rainfall to overspread the area SW- NE by late afternoon. Bumped up QPF amounts over some areas as well with now some 5-8 inch amts psbl ovr the sw Piedmont 2-5 inches elsewhere. Highs upr 70s-mid 80s. PVS DSCN: Rain will taper off and end fm WSW to ENE late this evening into early Fri morning. CAA sets in behind the system allowing temps to drop into the mid 50s NW to the mid 60s SE. Expect a period of gusty pressure gradient NNW (non-tropical) winds late tonight with inland gusts 30-40+ mph and 40-60 mph along the coast. && .SHORT TERM /FRIDAY THROUGH SATURDAY/... As of 445 AM EDT Thursday... The storm will quickly exit NE off the Mid Atlc coast and out to sea Fri morning into Fri aftn. Given the amount of dry air punching into the region behind the system, expect Fri to quickly become sunny or mostly sunny with breezy to windy conditions early. Dew points dropping into the 40s as well. Highs on Fri will range fm the mid 60s NW to lower 70s SE. Mostly clear to partly cloudy Fri night with lows ranging fm the mid to upper 40s nw, to the mid 50s sern coastal areas. S/W trof passes by north of the local area Sat morning. Will keep the forecast dry for now, with more cloudiness across the north. A stray afternoon shower will be possible north of the local area. Highs mainly 65-70. && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... As of 12 PM EDT Thursday... Cool and quiet conditions are expected to start the medium/long range forecast as high pressure at the surface will move east of the area on seasonally strong zonal winds aloft. As the surface high moves away, winds will become increasingly southerly Sunday night into Monday morning which will allow moisture to return to the region with dewpoints increasing through the day Monday into the mid 60s. An approaching trough of low pressure and an associated cold front will serve to increase the chance for showers and maybe a few rumbles of thunder for Monday afternoon into the evening hours. Some timing differences remain among the models as to the timing of the actual cold frontal passage with the GFS and GEM bringing the front through shortly after sunset on Monday while the ECMWF is a bit slower - closer to sunrise Tuesday morning. Went with a blend but leaned toward the faster timing of the GFS/GEM for frontal passage. The chance for thunder will come to an end after the front clears any one spot, but it appears that post-frontal showers will continue across the area for Tuesday into early Wednesday before high pressure builds into the region once again to close out the week. High temperatures on Monday will feel quite warm after a cool weekend with low 70s in the northwest ranging into the lower 80s across the southeast. Overnight lows Monday into Tuesday will depend on the eventual placement of the cold front but will generally range from the low 50s NW to low 60s SE. Daytime highs on Tuesday will be held in check with clouds and showers around, lower 60s across the north and some low 70s to the south. Thereafter, highs in the 60s to low 70s with lows dropping back into the 40s inland to upper 50s near the water. && .AVIATION /16Z THURSDAY THROUGH MONDAY/... As of 300 AM EDT Thursday... Early this morning, tropical cyclone Michael was located near the GA/SC border. Isolated to sctd shower bands well in advance of the storm were lifting nwrd into portions of the CWA. Conditions at the TAF sites ranged fm MVFR to VFR, but some obs over the piedmont were showing IFR Cigs fm stratus. Expect mainly sctd showers with MVFR or VFR conditions at the TAF sites thru the morning hrs well in advance of tropical cyclone Michael. Widespread RA/+RA will then overspread the area from WSW to ENE fm this aftn thru this evening, as the storm lifts NE thru NC into SE VA. The area of steady RA/+RA will not arrive in SBY until ~8 PM this evening. The steady RA/+RA will end from W to E acrs the region between 04-09z Fri. Visibilities will fluctuate between MVFR and (briefly) LIFR levels in the rain, with IFR or low-end MVFR CIGS through the duration of the steady RA/+RA. S/SE winds will likely gust to 15-30 kts this aftn at the coastal TAF sites. Winds turn to the NNW late tonight into early Fri morning, and are expected to briefly gust to 30-50 kt at the coastal sites, with 20-30 kt gusts expected at RIC. Winds slowly subside during the day on Fri, as Michael rapidly moves offshore away from the Mid-Atlc coast. OUTLOOK... Dry weather/VFR conditions are expected later Fri morning through Sun. && .MARINE... As of 430 AM EDT Thursday... SSE winds ~15 knots this morning per latest obs/buoy reports. Seas will average 3-4 feet and waves around 1 to 2 feet. Now T.S. Michael continues to slowly lift NNE over the deep south this morning. Models are still in good agreement w/lifting Michael along the Carolina coast today, eventually getting absorbed by an approaching upper level trough, and sending the remnant low across the NE NC/SE VA coast late tonight into early Friday, with the storm then accelerating offshore into the day on Friday. The flow will remain S-SE today, and will increase slightly due to the tightening pressure gradient. Winds quickly increase late today into Friday morning due to a combination of Michael and the approaching strong cold front from the northwest. Models remain in relatively good agreement on the mesoscale details. We have once again accelerated timing slightly per the official NHC official track. On this track, winds are expected to pick up out of the S/SE tonight across the southern waters with gusts as high as 50 knots possible. Winds then turn to the NNW Friday morning, behind the frontal passage and as the remnant low moves offshore. Winds may gust to 40 knots over a majority of the waters Friday morning with even higher gusts of 50 to 60 knots across the southern coastal waters/Bay. The current forecast has the strongest winds roughly between 8pm EDT/00z and 5am EDT/09Z Friday morning. The strongest winds diminish through the morning Friday, but breezy NW winds will linger Friday afternoon as high pressure builds over the Ohio Valley. Thus, expect a round of SCA will be needed for a period after current slate of marine headlines can be lowered. With respect to headlines, no changes have been made over the waters. Storm Warnings remain in effect for the ocean S of Parramore Is. and the entire Ches Bay, along with the Lower James River. The remaining zones have Gale Warnings. For land areas, a High Wind Warning is now in effect for portions of Eastern Virginia and Northeast North Carolina. With respect to land hazards, Wind Advisories extend further inland, surrounding the High Wind Warning. Additional Wind Advisories have been extended from along and SSE of a Farmville to Richmond and Tappahannock line. && .HYDROLOGY... Current river forecasts are based on expected QPF's. With the rain on our doorstep and flooding expected within 24 hours, will be issuing several river flood warnings today. && .TIDES/COASTAL FLOODING... As of 550 AM EDT Thursday... Have continued the coastal flood advisory from thu aftn through Fri morning for NC locations adjacent to the Currituck and Albemarle sound (including nearby rivers). Southerly to southeasterly winds are already pushing water levels higher along the northern shore of the Albemarle Sound based upon several tide gages at Edenton and Elizabeth City. As Tropical Storm Michael approaches this afternoon and evening, expect the winds to increase and water levels should continue to rise an additional foot to 2 feet. Elsewhere, tidal departures currently avg around +1.0 ft in the the Chesapeake Bay with gage locations in the Mid Bay having reach near minor flood stage in the last high tide cycle. With increasing southerly to southeasterly flow the next high tide cycle should continue to build upon those anomalies and continue to push higher water levels with minor flooding possible along tidal portions of the Potomac River and also for portions of the Lower Maryland Eastern Shore on the Bay side. The subsequent high tide cycle tonight a few hours either side of midnight might be the highest tide for the mid and upper bay as the wind flow increases ahead of the arrival of the center of Michael. How quickly the low moves past and the winds switch could impact that tide cycle as a quick switch could actually have a big impact for places like Cambridge where a quick switch to the NW could push water straight into town. That switch to the NW could also be a big impact in the southern Chesapeake Bay where some coastal flooding could linger into Friday morning with the next high tide cycle at locations like Sewells Point. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...Flash Flood Watch through Friday morning for MDZ021>025. Wind Advisory from 6 PM this evening to noon EDT Friday for MDZ021>025. Coastal Flood Advisory until 8 PM EDT this evening for MDZ021>023. High Surf Advisory from 9 PM this evening to noon EDT Friday for MDZ025. NC...Flash Flood Watch through Friday morning for NCZ012-013-030. Flash Flood Watch through Friday morning for NCZ014>017-031- 032-102. Wind Advisory from 6 PM this evening to noon EDT Friday for NCZ012>014-030>032. High Wind Warning from 6 PM this evening to noon EDT Friday for NCZ015>017-102. High Surf Advisory from 6 PM this evening to noon EDT Friday for NCZ102. Coastal Flood Advisory from 4 PM this afternoon to 8 AM EDT Friday for NCZ015>017-031-032-102. VA...Flash Flood Watch through Friday morning for VAZ048-060>062- 064>069-079>081-087-088-092-509>517. Flash Flood Watch through Friday morning for VAZ075>078- 082>086-089-090-093-095>100-518>525. Wind Advisory from 6 PM this evening to noon EDT Friday for VAZ060-065>068-075>085-087>090-092-093-096-512>524. High Wind Warning from 6 PM this evening to noon EDT Friday for VAZ086-095-097>100-525. High Surf Advisory from 6 PM this evening to noon EDT Friday for VAZ098. High Surf Advisory from 9 PM this evening to noon EDT Friday for VAZ099-100. Coastal Flood Advisory until 6 PM EDT this evening for VAZ075- 077. MARINE...Storm Warning from 6 PM this evening to noon EDT Friday for ANZ630>634-638-654-656-658. Gale Warning from 9 PM this evening to noon EDT Friday for ANZ650-652. Gale Warning from 6 PM this evening to noon EDT Friday for ANZ635>637. && $$ SYNOPSIS...TMG NEAR TERM...MPR/TMG SHORT TERM...MPR/TMG LONG TERM...RHR AVIATION...TMG MARINE...AJB/MAM HYDROLOGY... TIDES/COASTAL FLOODING...