Area Forecast Discussion
Issued by NWS Wilmington, NC

Current Version | Previous Version | Text Only | Print | Product List | Glossary On
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
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
831 FXUS62 KILM 290000 AFDILM Area Forecast Discussion National Weather Service Wilmington NC 800 PM EDT THU JUL 28 2016 .SYNOPSIS... High pressure will continue to bring oppressive heat and humidity to the region through Saturday. The high will begin to break down over the weekend leading to increasing chances of showers and thunderstorms beginning Sunday and continuing through the middle of next week. && .NEAR TERM /UNTIL 6 AM FRIDAY MORNING/... As of 800 PM Thursday...Atleast there is a breeze across the ILM CWA early this evening complements of the inland progressive sea breeze and a somewhat tightened sfc pg. The sea breeze will dissipate later this evening however, the low level jet will again become active with progged sw-wsw winds at 25 to 35 kt, peaking during the pre-dawn Fri hours. Given persistence, NO pops and skies becoming clear, with scattered cirrus at best. Persistence also applies to overnight temps and dewpoints, depending how far inland the hier dewpoints progress in the wake of the sea breeze. Some 80+ degree lows to occur along the coastal counties. pREVIOUS......................................................... As of 3 PM Thursday...Heat wave continues and the upper ridge will for one more day quash any convection. Excessive Heat Warning continues for the Cape Fear region and while ILM ASOS has shown falling dewpoints all day most mesonet sites have not and feel that the Warning is likely verifying for the most part. This may be some local effect as the ASOS is in such an open field. Even so, KLTX showing the marine layer creeping into the area and dewpoints are likely to rise. Any place within the Warning seems fair game to meet criteria between now and about 6 pm. The Warning goes till 8 mainly to avoid having to "step down" to an Advisory for just a few hours this evening. Tonight will be muggy with lows in the mid 70s inland to around 80 most coastal locales. && .SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/... As of 3 PM Thursday...While not exactly a refreshing cooldown by any means there actually may not be any heat products needed tomorrow. Piedmont trough pushes east enough to advect the higher dewpoints offshore. Heat indices generally in the 100-104 range. The mid level ridge is also beaten down by broad, weakly cyclonic belt of westerlies across the Great Lakes/Ohio Valley. This means that a few spots may actually be able to support some diurnal convection. The Cape Fear area sea breeze appears to have the best shot while a secondary max should be far NW zones in association with the trough. Places farther south still look too capped. Saturday is starting to look interesting. The Piedmont trough closes off a weak low and forecast soundings show a lessening of the mid level dry air that has been so instrumental in squelching convection. Also interesting is that guidance shows that afternoon temperatures get warmer again and we are looking at a Heat Advisory again. && .LONG TERM /SUNDAY THROUGH THURSDAY/... As of 3 PM Thursday...Mid level pattern will have transitioned to troughing by the start of the period, with the strength of the 5h trough increasing slightly Mon and Tue. A cold front will move into the region during the middle of next week but this feature is likely to stall just north and west of the area. This will leave the Piedmont trough and the daily sea breeze, along with the Bermuda High, as the most significant surface features during the period. Mid level cooling and deep moisture, PWATs will be around 2 inches Sun into Tue, will lead to a steady increase in precip chances Sun and Mon. Likely pop is warranted across the region Mon and Mon night before the mid level axis moves overhead Tue. The trough axis brings an increase in dry air aloft and weak downward motion, causing a decreasing trend in precip chances for the middle of the week. Pop will still be on the high side Tue as deep moisture holds on but by Wed PWATs drop down near 1.5 inch and remain there through Thu. Temperatures 5 to 8 degrees above climo Sun and Mon will trend back to climo for the middle of next week. && .AVIATION /00Z FRIDAY THROUGH TUESDAY/... As of 00Z...Potential for patchy areas of fog inland which could create marginal MVFR towards morning. Otherwise expect VFR through the valid TAF period. Quiet conditions prevail across the area this evening with nearly clear skies and gusty southwest winds. Anticipate gusts to subside over the next hour or two, with sustained winds around 10 kts or less overnight. Latest guidance continues to suggest patchy areas of fog developing towards morning, potentially creating areas of marginal MVFR. On Friday, VFR prevails with southwest winds 10 to 15kts with higher gusts in the afternoon. EXTENDED OUTLOOK...Isolated to scattered afternoon convection Sunday and onward through the forecast will create fleeting and localized MVFR/IFR. Otherwise expect VFR. && .MARINE... NEAR TERM /THROUGH TONIGHT/... As of 800 PM Thursday...Once again, winds associated with the low level jet will take the place of the sea breeze with respect to increasing sustained sw-wsw winds and associated gustiness. This a result of the jet lying between 800 and 1200 ft mixing down to the ocean sfc. Significant seas will run 2 to 4 ft and primarily come from locally produced wind driven waves at 4 to 5 second periods. SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... As of 3 PM Thursday...Southwesterly flow continues between high pressure and the Bermuda high. Low level jet from the near term will persist but also weaken and move further offshore. This could cause the 4 ft seas to drop out of the forecast. Saturday looks like a bit of a repeat with light SW flow through the day and then a nocturnal jet at night that kicks up the winds and may even feature a return of 4 ft seas. LONG TERM /SUNDAY THROUGH TUESDAY/... As of 3 PM Thursday...Marine conditions will continue to be driven by the interaction of the Piedmont trough and the Bermuda High. SOuthwest flow will continue through the period with speeds closer to 10 kt in the morning, increasing to a solid 15 kt in the afternoon and evening. Seas continue to run 2 to 4 ft. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...None. && $$ SYNOPSIS...III NEAR TERM...DCH SHORT TERM...MBB LONG TERM...III AVIATION...SGL is the U.S. government's official web portal to all federal, state and local government web resources and services.