Area Forecast Discussion
Issued by NWS Wilmington, NC

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
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS62 KILM 140103 AFDILM Area Forecast Discussion National Weather Service Wilmington NC 903 PM EDT Sun Aug 13 2017 .SYNOPSIS... A cold front will approach the area from the northwest today then stall and meander across the forecast region through midweek. Mid level riding will erode this front late in the week bringing a return to more typical summertime heat and humidity along with slightly lower thunderstorm chances. Another cold front will approach next weekend. && .NEAR TERM /THROUGH MONDAY/...
-- Changed Discussion --
As of 845 PM Sunday...A plethora of boundaries reside across the ILM CWA with plenty of interactions still ongoing. Based on latest 88D mosaics, the overall coverage of convection has decreased across the Eastern Carolinas and will indicate this in the latest update for this evening. Overall, will trend down POPs to low or even slight chance respectively. With a moisture-laden atmosphere, PWs above 2 inches, any convection that does occur will primarily be heavy rain producers that could result in localized flooding across prone locations such as poorly drained and low lying areas. Have included patchy to areas of fog, especially away from the immediate coast, during the pre-dawn Mon hrs and extending up to a few hrs after daybreak. Model guidance even suggests the possibility of dense fog and low clouds, below 1k ft, in the vicinity and north of the meandering frontal boundary. Low temps tonight in the mid and upper 70s to around 80 along the immediate coast. Previous................................................... As of 300 PM Sunday...Convection this afternoon concentrated along the sea breeze front near the coast and along a stalled cold front oriented NE to SW west of LBT and FLO. Analysis of morning data and latest guidance show a moderately unstable and very moist atmosphere with severe weather unlikely but very localized flooding from training storms a concern for the remainder of the daylight and evening hours. High-Res data does show some filling in between the above mentioned lines of convection and this looks good given impending multiple boundry interactions. However, this same guidance also shows activity will mostly fade with the setting sun. For Monday, expect more of the same with the stalled front wavering in the area and a continued moist and moderately unstable airmass. Temperatures will show little change from recently experienced. Expect lows tonight in the mid to upper 70s, with highs Monday in the mid to upper 80s. Elevated dewpoints will give us heat index values of around 100F.
-- End Changed Discussion --
&& .SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/... As of 300 PM Sunday...The pattern we have seen the past several days will continue through the short term period. This consists of a moisture rich southwest flow featuring persistent precipitable water values over two inches. A weak boundary wavering around the area (mostly inland) will provide an impetus for convection along with the sea breeze and numerous outflow boundaries and differential heating. The highest pops, likely values, occur Tuesday afternoon with good chance and chance for the other periods. Tuesday`s highs will be in the upper 80s to near 90, depending on the convection with overnight lows pegged in the middle 70s for the most part. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/...
-- Changed Discussion --
As of 300 PM Sunday...A return to summer heat and humidity occurs late week as the mid-level trough finally gives way to SE ridging. This ridge amplifies in response to a trough digging across the west, and will drive increasing thicknesses, and hence temperatures, into the Carolinas into next wknd. Despite this ridge expanding from the Gulf Coast, heights locally may be relatively lowered thanks to several weak impulses moving to the north in the zonal flow across the Mid-Atlantic. These subtly steeper lapse rates will combine with PWATs still above 2 inches, and strong instability thanks to highs into the 90s to keep the chance for showers and tstms in place each aftn/eve through late week, although with coverage likely less than we have seen much of August so far. By Saturday, a cold front will dig through the OH VLY and then stall in the vicinity causing renewed good chances for convection and slightly cooler temperatures. However, with the ridge overhead this front may entirely dissipate by the end of the period instead of lingering like many of our summer-time fronts so far this season.
-- End Changed Discussion --
&& .AVIATION /00Z MONDAY THROUGH FRIDAY/... As of 00Z...Bouts of MVFR and IFR conditions will occur this evening from convection. The dynamics driving the ongoing convection are due to a stalled frontal boundary, a plethora of outflow boundaries, and whats left of the sea breeze. Activity will become more isolated by midnight and there-after. With the frontal boundary snaking across the region, the threat for low clouds and fog, possibly dense, will become a reality for the inland terminals with LBT having the best chance to see LIFR conditions. The fog and low clouds should disperse by mid daytime morning. Convection will spring up once again by early Mon aftn and persist into the evening. Latest models indicate, this convective activity may not be as widespread like what occurred Sunday. Will still highlight the best chance for convection with tempo groupings. Extended Outlook...There is a chance for MVFR/IFR ceilings and visibility in showers and thunderstorms Mon Eve through Thu due to a persistent stalled frontal boundary meandering across the area. Each morning could see MVFR/IFR conditions from low ceilings and reduced vsby from fog. && .MARINE...
-- Changed Discussion --
NEAR TERM /THROUGH MONDAY/... As of 845 PM Sunday...The stalled front will remain north and inland from the coast overnight thru Mon. The resulting sfc pressure pattern will produce a S to SW wind direction. The sfc pg will remain rather loosened with resulting speeds around 10 kt or less. Significant seas overnight thru Monday will run 2 to 4 ft, with the 4 footers primarily off Cape Fear. The 4 footers will become more pronounced across all waters late Mon and Mon night due to the closest approach of Gert, which will pass well offshore from the ILM local waters. Previous.................................................. As of 300 PM Sunday...High pressure over the western Atlantic will keep winds southerly in the 10 kt range through the period, with gusts up around 20 kts during the afternoon hours and near convection. Seas will range right around 3 ft, give or take a foot, through Monday. SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/... As of 300 PM Sunday...Southwest winds of 10-15 knots will persist throuigh the period. The speeds will lean moreso to the lower end of the range. Significant seas will be 2-4 feet with a general mix of a modest wind wave and swell component. LONG TERM /WEDNESDAY THROUGH FRIDAY/... As of 300 PM Sunday...Broad high pressure offshore will exert its influence across the waters through late week. This creates SW winds through the period, with speeds only increasing above 10 kts on Friday in response to a cold front approaching from the NW. The prolonged fetch around the offshore high pressure will allow a 1- 2ft/9sec SE swell to persist through the end of the week, but this will become masked by an amplifying 5 sec SW wind wave, especially the latter half of the period. These 2 primary wave groups will create seas of 2-3 ft Wed/Thu, rising to 3-4 ft on Friday.
-- End Changed Discussion --
&& .ILM WATCHES/WARNINGS/ADVISORIES... SC...None. NC...None. MARINE...None. && $$ SYNOPSIS...JDW NEAR TERM...DCH/REK SHORT TERM...SHK LONG TERM...JDW AVIATION...DCH

USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.