Area NWS Forecast Discussion
066 FXUS62 KILM 120529 AFDILM Area Forecast Discussion National Weather Service Wilmington NC 1229 AM EST Thu Dec 12 2019 .SYNOPSIS... High pressure will bring a chilly period through Thursday. A coastal trough and wave of low pressure will bring rain late Friday through Saturday morning. High pressure will then give way to a cold front on Tuesday. && .UPDATE... High clouds are now clearing out of Bennettsville, Darlington, and Florence and are still expected to be off the coast before midnight. Tweaks to wind direction, dewpoints, and sky cover have been made to the forecast based on current obs. No changes to low temp forecasts. && .NEAR TERM /THROUGH FRIDAY/... The weather for the next 36 hours will be dominated by high pressure behind a cold frontal passage that brought a big temperature change and gusty winds to the Cape Fear region. Highs this afternoon under cold air advection will range from the upper 40s to the lower 50s, which is between 5 and 10 degrees below normal and between 20 and 30 degrees below yesterdays maximum afternoon temperatures. As strong high pressure to the north moves eastward, the surface pressure gradient will allow for gusty winds up to 30 mph at times today and tonight. The wind direction will shift from the northwest to the northeast as the high pressure moves eastward Thursday and winds should relax a bit, although gusts could still reach into the 20 mph range at times Friday afternoon and evening. && .SHORT TERM /FRIDAY NIGHT/... A good dose of warm advection-induced rain to spread across the area late Friday. The better dynamics come Friday night but it appears they will lag the deep moisture. With this lack of phasing and poor deep layer lapse rates convection may be hard to come by, even the elevated variety. Near seasonable highs on Friday will not fall much Friday night in the ongoing warm advection. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... Rain may linger a bit into Saturday even though the deep moisture will be moving off the coast-the main vort max will still be crossing the area. Dry air moves in Saturday night. By Sunday any weak cool advection will be offset by the return of sunshine and a fairly seasonable weekend is expected. Warm and moist advection spread west-to-east on Monday first only leading to increasing clouds but then rain chances. Tough to say when the latter materializes as it may be quite gradual and usually a bit slower than progged by models. Also, most of the WAA rain may stay north of the CWA and the best rain chances may come on Tuesday with cold frontal passage. && .AVIATION /06Z THURSDAY THROUGH MONDAY/... VFR through the 06Z TAF period as a few high clouds transition to sct-bkn late in the TAF period. N winds of 5 to 10 KT early this morning will become NE 10-15 kts after daybreak with gusts near 20 kts. Extended Outlook...Another round of MVFR/IFR is possible Friday into Saturday as an area of low pressure moves by the coastal Carolinas. VFR expected Sunday and Monday. && .MARINE... High pressure will keep things dry offshore, but a building pressure gradient offshore is expected to kick up north to northeast winds over the next 36 hours between 20 and 25 kts with gusts up to 30 kts at times. Significant wave heights between 5 and 7 feet are possible, especially beyond 10 NM. Wave trains from the southeast between 8 and 10 seconds and the north between 6 and 8 seconds. A small craft advisory remains in effect. Winds and seas may dip below advisory thresholds on Friday as a coastal trough weakens the gradient. Surface low pressure moves up the coast Friday night and cold frontal passage expected to lead to a sharp turn to offshore flow soon thereafter on Saturday. The following cold air push may allow some 6 ft seas to once again necessitate an advisory, though it may be short-lived. Weakening winds and diminishing seas Sunday into early Monday as weak high moves off the coast. A return flow/southerly winds establishes itself by Monday. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...None. NC...None. MARINE...Small Craft Advisory until 6 AM EST Saturday for AMZ250-252- 254-256. && $$ SYNOPSIS...MBB UPDATE...TRA NEAR TERM...MCK SHORT TERM...MBB LONG TERM...MBB AVIATION...MAS/RAN MARINE...MCK/MBB