Area NWS Forecast Discussion
000 FXUS62 KILM 120241 AFDILM Area Forecast Discussion National Weather Service Wilmington NC 941 PM EST Tue Dec 11 2018 .SYNOPSIS... Dry and seasonable high pressure will affect the area tonight through Thursday. Low pressure enters the region early Friday, continuing into Saturday. Expect substantial rain totaling between 2 to 3 inches from this storm system. High pressure returns Sunday through early next week. && .NEAR TERM /THROUGH WEDNESDAY/... As of 941 PM Tuesday...High pressure will remain in control of the weather tonight through Wednesday, which will bring sunny skies and dry conditions through the near term forecast period. As a result of the cooler air mass and clear skies tonight, temperatures are on track to drop into the upper 20s to lower 30s across the region. Latest model soundings show some lower moisture at the lower levels as a result of recent rainfall and saturated ground conditions, but with overnight temperatures at or near freezing should result in a frosty night. Some minor patches of fog cannot be ruled out tonight, but widespread fog tonight is not anticipated at this time. Southerly wind directions at the surface Wednesday will cause an uptick in afternoon temperatures into the lower to mid 50s under plenty of sunshine, which is just a few degrees below normal for mid December. && .SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/... As of 345 PM Tuesday...Zonal to weak ridging aloft will dominate Wed night into Thu. The center of sfc high pressure overhead Wed night will provide a decent radiational cooling night if the Cirrus aloft is not too thick. Went along with the colder guidance for Thu lows. The ridge axis aloft pushes overhead and east of the FA by Thu evening. This will open up flow from the SW with tapping of moisture from the Gulf of Mexico. The flow aloft will continue to amplify due to the intensifying upper s/w emerging out of the southern Rockies and closing off as it reaches the NW Gulf Coast States by Friday daybreak. Flow in the lower levels on the backside of the high Thu thru Thu night will provide increasing Atlantic moisture across the FA. Have indicate stratiform light rain breaking out and overspreading the FA from SW to NE, mainly after midnight Fri, with POPs in the mid to high end chance by daybreak Fri. Max temps Thu will be right at climo with Thu night lows only dropping into the mid and upper 40s via latest MOS consensus. .LONG TERM /FRIDAY THROUGH TUESDAY/... As of 345 PM Tuesday...Excellent pcpn event shaping up for the forecast area with storm totals ranging from 2 to 3 inches in the time range between Pre-dawn Fri and Sunset Saturday. Possibly more if the closed upper low over the Gulf Coast States takes its sweet o`le time lifting toward the NE. The longer it takes, the longer the inflow of moisture from both the Atlantic and the Gulf of Mexico. No pcpn type issues!! Much too warm!! The bulk of the pcpn will fall from midday Friday thru Sat daybreak...along with the threat of isolated thunderstorms especially ahead and along the occluded front as it lifts across the FA by daybreak Sat. During Sat into Sun, the upper low lifts across the FA and will continue to carry chance POPs as a result. Temps will be on the mild side The sfc pg remains tightened, keeping winds breezy especially during daylight. For Mon into Tue, WNW to NW flow aloft becomes better entrenched across the FA could be the beginnings of a change in the longwave pattern aloft. Have indicated a decrease in MAX/MIN temps each successive day from Sun thru Tue. During this latter range, sfc high pressure will drop southeast from Canada aiding the colder trend during the 3 days (Sun thru Tue). && .LONG TERM /FRIDAY THROUGH TUESDAY/... As of 345 PM Tuesday...Excellent pcpn event shaping up for the forecast area with storm totals ranging from 2 to 3 inches in the time range between Pre-dawn Fri and Sunset Saturday. Possibly more if the closed upper low over the Gulf Coast States takes its sweet o`le time lifting toward the NE. The longer it takes, the longer the inflow of moisture from both the Atlantic and the Gulf of Mexico. No pcpn type issues!! Much too warm!! The bulk of the pcpn will fall from midday Friday thru Sat daybreak...along with the threat of isolated thunderstorms especially ahead and along the occluded front as it lifts across the FA by daybreak Sat. During Sat into Sun, the upper low lifts across the FA and will continue to carry chance POPs as a result. Temps will be on the mild side The sfc pg remains tightened, keeping winds breezy especially during daylight. For Mon into Tue, WNW to NW flow aloft becomes better entrenched across the FA could be the beginnings of a change in the longwave pattern aloft. Have indicated a decrease in MAX/MIN temps each successive day from Sun thru Tue. During this latter range, sfc high pressure will drop southeast from Canada aiding the colder trend during the 3 days (Sun thru Tue). && .AVIATION /03Z WEDNESDAY THROUGH SUNDAY/... As of 00Z...Only potential aviation concern overnight will be a slight chance of fog. Most areas will be at or below freezing by 08Z, so any condensation will likely end up being frost. Winds will become near calm by 02Z. Wednesday, another VFR sunny day with only cirrus drifting in from time to time. Light winds. Extended Outlook...VFR continuing through Thu before a return to MVFR Fri potentially due to another coastal low bringing lower ceilings and visibility due to rain and even a few thunderstorms. && .MARINE... NEAR TERM /THROUGH WEDNESDAY/... As of 941 PM Tuesday...SCA has been allowed to expire this evening as wave heights and wind speeds have diminished below threshold levels of concern. High pressure continues to dominate tonight through Wednesday with little concern for wave heights through the near term forecast period. Expect waves between 2 and 3 feet with mainly offshore winds between 5 and 10 kts. SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/... As of 345 PM Tuesday...Mariners will have favorable conditions from sunset Wed thru sunset Thu to venture out into the Atlantic, Winyah Bay and along the Intra-Coastal Waterway. This a result of sfc high pressure overhead. Winds and sea conditions will begin to deteriorate Thu night as the high slides offshore and a very dynamic low taking shape across the Northern Gulf Coast by the end of this period. Look for ENE to ESE winds to increase to 15 to 20 kt by daybreak Fri and building wind driven seas to 3 to 5 ft. And in addition, reduced vsby from pcpn. LONG TERM /FRIDAY THROUGH SUNDAY/... As of 345 PM Monday...Winds and sea conditions will NOT be favorable for mariners this period. A well tightened sfc pg ahead of the occluded front Fri thru Fri night, will produce SE winds Fri, S Winds Fri night, in the 20 to 30 kt range with a few gusts up to Gale Force mainly Fri night as the occlusion pushes closer. Seas will respond and build to 6 to 10 ft with the higher seas off Cape Fear and Romaine respectively. Mainly dealing with windwaves with not much of a ground swell aiding seas during this time-line. And will have areas of vsby reduced to 1 nm or lower at times from the heavier rain and isolated thunderstorms. Expect improving wx conditions by midday Sat thru Sun as the closed low lifts northeast of the area. The sfc pg to relax ever so slightly, but will be conducive to 15 to 20 kt winds. After the occlusion pushes thru early Sat, expect Westerly directions veering to NW on Sun. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...None. NC...None. MARINE...None. && $$ SYNOPSIS...DCH NEAR TERM...MCK SHORT TERM...DCH LONG TERM...DCH AVIATION...DL MARINE...MCK