textproduct: NWS Wilmington

WHAT HAS CHANGED

As of 530pm... Updated near-term temps, dew points, winds, sky cover, and PoPs to better reflect current obs and expected trends.

As of 220pm... Recent models show greater influx of moisture on Wednesday, leading to increased forecast rain chances and increased QPF.

KEY MESSAGES

KEY MESSAGE 1...The next cold front arriving Wednesday night appears likely to bring some measurable rainfall to most portions of the eastern Carolinas.

DISCUSSION

KEY MESSAGE 1: The next cold front arriving Wednesday night appears likely to bring some measurable rainfall to most portions of the eastern Carolinas.

We should get get a couple of dry days (Monday and Tuesday) between today's rain-maker and the next frontal system which looks to arrive late Wednesday. Confidence in measurable rainfall is growing and our latest forecast PoPs just ahead of the front Wednesday range from 60-80 percent across the area. Forcing for Wednesday's rain event doesn't look too bad. A modest 500 mb shortwave should pass across the area during the day Wednesday. While that in itself is not too impressive, the 300 mb pattern features substantial visual diffluence and calculated mass divergence which should support sustained synoptic lift beneath. Co-located with this upper support will be a stream of west Gulf moisture with precipitable water ranging from 1.6 to 1.8 inches, above the 90th percentile values for the date. This should support an area of rain, possibly with some embedded convection, crossing the area. Latest model blend QPF is 0.2 to 0.4 inches.

There is still spread in timing of the surface cold front's arrival ranging from 06z Thu on the 00z runs of the ECMWF and Canadian, to as late as 12-18z Thu on the 06z and 12z runs of the GFS. The mean ensemble solution (based on last night's 00z/06z models) shows the front marching across the area between midnight and 5 AM Thursday with most of the weather well out ahead of it. While our forecast has features a long period of rain chances, it's likely the rain will be fairly short duration tied to the passage of the good dynamics.

Dry and cooler weather should build in again for Thursday as the front moves offshore.

AVIATION /21Z SUNDAY THROUGH FRIDAY/

The cold front is just pushing into the area from the north but northerly winds are already established, speeds ~10-12 kts with some gusts 20-22 kts. CIGs near 1000 ft are in SE NC and should spread into NE SC with the progression of the front. The clouds will stick around at the coast through the majority of the period but there's some uncertainty inland due to drier air coming in overnight into Monday morning with more gradual clearing towards the end of the period. NE winds will continue ~10 kts.

Extended Forecast...Predominantly VFR through Tuesday. Increasing rain and storm chances due to another front could bring MVFR/IFR restrictions Wednesday through Thursday.

MARINE

Through Monday...A cold frontal passage with high pressure ridging in behind it will lead to unfavorable marine conditions. NE winds gusting near 25 kts with seas up to 6 ft will keep a Small Craft Advisory for the coastal waters through most of the day Monday. The offshore waters could see gusts near 30 kts ~60 NM out, with waves 7- 9 ft.

Monday night through Friday...A narrow ridge of high pressure extending from New England through the Carolinas on Monday night will slowly weaken and shift offshore through Wednesday. This should lead to a 36-hour period of diminishing winds and subsiding seas. Low pressure moving from the Ohio Valley Wednesday into Canada Wednesday night will drag a cold front eastward and through the eastern Carolinas late Wednesday night. Increasing southwest winds and good chances of showers and maybe thunderstorms are expected ahead of the front. Winds should shift north to northeasterly behind the front Thursday through Friday along with drying weather as high pressure builds overhead.

CLIMATE

This was the first widespread rainfall event across the area in 19 days. Rainfall deficits just this month were 1.5 to 2.2 inches, and over the past three months are 4 to 6 inches. This rain event, while welcome, did not appreciably improve the drought. Also of note, coastal Brunswick County plus the majority of Horry and Georgetown counties along the SC coast picked up little, if any, rain.

Preliminary rainfall totals from yesterday afternoon through 2 PM today:

Pender County: Currie-3 miles East 0.75" Holly Shelter Gameland-Back Island 0.61" Burgaw-1 mile NE 0.51" Hampstead-4 miles NW 0.56"

New Hanover County: Castle Hayne-NCSU Econet 0.54" Wilmington Airport ASOS 0.43" Wilmington-Kings Grant 0.41" Wilmington-near Mayfaire 0.41" Wrightsville Beach 0.29" Carolina Beach 0.69"

Brunswick County: Leland-Willow Woods 0.37" Sunny Point Military Terminal 0.51" Southport 0.06" Bald Head Island-NCSU Econet 0.03" Ocean Isle Beach-3 miles NW 0.02"

Columbus County: Chadbourn-2 miles south 0.79" Whiteville-NCSU Econet 0.68" Tabor City-3 miles NE 0.25" Bug Hill-2.5 miles SE 0.17"

Bladen County: Dublin-4 miles NE 0.80" Bladen Lakes State Park 0.65" Bladenboro 0.84"

Robeson County: Rowland 0.78" Lumberton 7 miles NE 1.00" Lumberton Airport ASOS 0.85" Lumberton RAWS station 1.00"

Horry County: Green Sea-3 miles North 0.03" Conway-Coastal Carolina Univ 0.03" North Myrtle Beach Airport ASOS Trace

Georgetown County: Georgetown Airport-1 mile NE 0.08" Georgetown-Tidelands Hospital 0.04"

Dillon County: Dillon 1.30"

Marion County: Marion-3 miles S 0.01"

Florence County: West Florence 0.19" Florence Airport ASOS 0.31" Mars Bluff 0.12" Effingham-7 miles SW 0.28" Scranton-2 miles W 0.41"

Darlington County: Clyde-3 miles W 0.39" North Hartsville-2 miles N 0.40"

Marlboro County: Bennettsville-2 miles SE 0.30"

ILM WATCHES/WARNINGS/ADVISORIES

NC...None. SC...None. MARINE...Small Craft Advisory until 6 PM EDT Monday for AMZ250. Small Craft Advisory until 6 PM EDT Monday for AMZ252-254-256.