Area Forecast Discussion
Issued by NWS Wilmington, NC

Current Version | Previous Version | Graphics & Text | 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
-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS62 KILM 211915 AFDILM Area Forecast Discussion National Weather Service Wilmington NC 315 PM EDT Sun May 21 2017 .SYNOPSIS... Today will feature mostly cloudy skies with only a slight chance of showers. The upcoming work week looks rather unsettled with a series of storm systems moving across the southeast. The best chances of rain occur from late Monday through Wednesday. Conditions should dry out somewhat toward the end of the week. && .NEAR TERM /THROUGH MONDAY/...
-- Changed Discussion --
As of 3 PM Sunday...Dry air air aloft will give way to a sharp rise in column moisture in the late evening near I-95 and into the pre- dawn hours at the coast. Until this time not a great deal of measurable rain is expected although a pop up shower or debris rain advecting from the south may bring some drops. Showers and a few TSTMS will become more likely into Monday as a cold front from the west edges closer, then stalls near the coast late in the day Monday. As a result, mentionable POP values will prevail later tonight through the day Monday. Best QPF fit from overnight through Monday yields up to half inch well inland to 1/10th to 1/4 inch closer to the coast. Low-level winds are not particularly strong with this system but any TSTMS Monday could generate a 40-45 mph gust. Lows tonight to remain mild in a developing warm sector and may even rise a few degrees in the pre-dawn hours, mins mainly upper 60s to low 70s. Clouds and periods of rain Monday will limit max temps to mainly the low and middle 80s.
-- End Changed Discussion --
&& .SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/...
-- Changed Discussion --
As of 3 PM Sunday...Broad 5h troughing over much of the CONUS during the period will maintain unsettled weather through Tue night. Weak cold front stalls in the region Mon evening, ending up parallel to the steering flow. Weak low developing along the front over AL will track northeast along the front Mon night into Tue. Deep southwest flow, directing the low northeast, will help spread deep Gulf moisture over the region. Precipitable water values are forecast to approach 2 inches Tue and the weak, but developing low will help provide upward motion. Shortwaves within the large scale 5h trough will further enhance upward motion, timing dependent. Worth noting that the bulk of the guidance is about 12 hours slower with the development of this scenario compared to Sat, mainly due to the 5h trough being more amplified. However, thinking has not changed much and all of the guidance still has the low developing and tracking northeast, across the western Carolinas. Best rainfall chances and highest rainfall totals are expected across inland areas, closer to the surface low, but just about the entire region should receive rainfall from this event. Surface low moves off the coast near the NC/VA border Tue evening, but with the 5h trough axis remaining west of area the front will continue lingering in the area. Larger differences between the guidance are evident Tue night but most agree that at least a portion of the Tue night period has a good chance of being wet. Coverage will be a little less than during the day Tue but still potential for showers and thunderstorms with both PVA ahead of any shortwaves and lingering front having an abundance of deep moisture to tap into. Also evidence of an increasing low level jet Tue night, some disagreement on exactly how strong but range of solutions is 40- 50 kt which is sufficient to enhance dynamics. Clouds and low level moisture/rain will keep highs near to slightly below climo but help keep lows above to well above climo.
-- End Changed Discussion --
&& .LONG TERM /WEDNESDAY THROUGH SUNDAY/...
-- Changed Discussion --
As of 3 PM Sunday...Relatively narrow warm sector spreads into the area on Wednesday. The warm front early may bring some light rain but the approach of the cold front yield the more significant rise in POPs as well as the chance for higher rainfall amounts. Wind fields not quite as strong as previously forecast and instability should be limited by cloud cover so severe weather threat seems minimal. The main energy associated with the upper trough crosses Thursday but the deepest moisture will be well offshore by then. Even so, the strength of the main vorticity max should be able to wring out a few showers especially if breaks of sunshine provide some instability. Deep layer westerly flow will bring sunshine on Friday with much lower humidity levels that will recover slightly into Saturday. A healthy disturbance may come across in this zonal flow on Sunday bringing some minor rain chances.
-- End Changed Discussion --
&& .AVIATION /19Z SUNDAY THROUGH FRIDAY/... As of 18Z Sunday...Occasional MVFR ceilings through afternoon but not much convective activity expected along a stalled front with dry air above 6000 ft. MVFR/IFR ceilings developing overnight ahead of a cold front from the west, with SHRA/TSTMS possible mainly from daybreak Monday onward to end of this TAF cycle. Surface wind gusts to 35 kt in TSTMS Monday morning. MVFR/IFR ceilings with shra/TSTMS 12z-18z Monday. Outside of convection, sfc winds SSE tonight and SSW Monday morning generally 12 kt or less. Extended Outlook...Reduced flight categories will be possible in periodic showers and thunderstorms Monday afternoon through Wednesday. The strongest convective activity will occur during Wednesday. && .MARINE...
-- Changed Discussion --
NEAR TERM /THROUGH MONDAY/... As of 3 PM Sunday...Marine conditions will worsen a bit into early Monday and through the day but an advisory may not be needed. Still a bit rough however with 20 KT southerly gusts and seas between 3-4 feet with southerly exposure. Showers and TSTMS will increase on the waters Monday and any storms could produce gusts as high as 40 KT. Seas will be a mix of SE waves 2 feet every 7-8 seconds and S waves 2-3 feet every 4-5 sec. SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/... As of 3 PM Sunday...High pressure remains well off the coast but its influence continues to weaken. Southwest flow will be maintained through the period but gradient will be pinched between the high and a series of developing surface waves that will track northeast along the front stalled just west of the waters. Southwest flow increases from 10 to 15 kt Mon night to 15 to 20 kt Tue before dropping closer to 15 kt later Tue night. Increase in winds is related to the passage of the surface waves so an difference in timing or strength of these features would have a direct impact on wind speeds. Seas around 3 ft Mon evening build to 3 to 4 ft Mon night, peaking at 3 to 5 ft Tue and Tue night. LONG TERM /WEDNESDAY THROUGH FRIDAY/... As of 3 PM Sunday...Broad swath of southwesterly flow in place on Wednesday between large Atlantic high and cold front approaching from the west. Winds may not ramp up to advisory levels but seas likely will. This boundary will turn the flow from SW to W by Thursday as well as a small decrease in overall wind speed allowing seas to abate below advisory thresholds. The circulation and gradient associated with the front will finally move east of the area by Friday as high pressure builds into Florida and the Bahamas. Locally wind will remain westerly and continue to abate. Seas will follow suit.
-- End Changed Discussion --
&& .ILM WATCHES/WARNINGS/ADVISORIES... SC...None. NC...None. MARINE...None. && $$ NEAR TERM...MJC SHORT TERM...III LONG TERM...MBB AVIATION...MJC

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