textproduct: NWS Wilmington

SYNOPSIS

An approaching cold front will lead to warm and breezy conditions develop over the weekend, the front moving offshore Sunday night. High pressure will build in before another front impacts the area, isolated light rain possible Tuesday night. The front may linger in the area but mostly dry conditions will prevail.

NEAR TERM /THROUGH SATURDAY/

Satellite imagery reveals clear skies across the Carolinas downstream of a large upper ridge over the central part of the country. Surface high pressure centered over South Carolina is supported by the convergent upper level flow east of this ridge. The surface high should drift southward overnight toward the Florida- Georgia state line by sunrise Saturday.

A strong radiational inversion should develop this evening. As the high sinks south overnight winds just above the surface should increase and may become strong enough (30 knots) to disturb the inversion after midnight, especially north of Florence, Dillon, and Whiteville. Inland lows should reach 39-43 with mid 40s on the coast.

Wind gusts of 25 mph are possible Saturday as vertical mixing brings down some of the higher momentum down from aloft. 850 mb temps of +9 to +10C today should warm to +12 to +14C Saturday afternoon, supporting inland highs in the mid 70s with 69-72 near the coast. Clear skies should begin to cloud up some in the afternoon as Pacific jet stream moisture increases at and above 400 mb.

SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/

Low pressure to our north and high pressure to our south will sandwich the area ahead of a cold front. This will result in breezy SW winds overnight Saturday into Sunday, becoming more westerly as the front approaches throughout the day. The front will push offshore Sunday night with no rain expected as we remain steeped in dry air and better forcing sticks to our north. Some increase in cloud cover can be expected with the frontal passage with clear skies returning for Monday. Winds will be lighter as high pressure starts to move in, and temperatures will be knocked down below normal Monday. Lows in the mid 50s Saturday night and near 40 Sunday night. Highs in the mid to upper 70s Sunday and lower to mid 60s Monday.

LONG TERM /MONDAY NIGHT THROUGH FRIDAY/

Dry conditions will hold until Tuesday night where another cold front approaches, possibly stalling in the area through the rest of the period. This feature could bring us some isolated light rainfall as we get another push of moisture from around the departing high, from the W/SW. Predominantly dry conditions should prevail through the end of the period with temperatures near to just above normal.

AVIATION /18Z FRIDAY THROUGH WEDNESDAY/

VFR conditions will continue through the next 24 hours. A moderate west-southwesterly low level jet will develop after 05z tonight, but computed shear within the lowest 2000 feet should remain below LLWS criteria. Southwest winds could gust to 20 kt during the day Saturday.

Extended Outlook...VFR.

MARINE

Tonight through Saturday...High pressure centered over South Carolina will sink south to near the Florida-Georgia state line Saturday morning, then down to central Florida by Saturday afternoon. This should lead to a gradual increase in winds across the Carolina coastal waters. Moderate northeasterly winds blowing this afternoon should become light and variable by sunset as the ridge axis moves south across the area. Winds should turn southwesterly overnight, increasing to 15 knots Saturday morning and then to 15-20 knots Saturday afternoon.

Aside from a very small 8-second southeasterly swell, seas should consist almost entirely of local wind waves. Combined seas of 1-2 feet tonight should build toward 3 feet Saturday afternoon.

Saturday Night through Wednesday...Low pressure to our north and high pressure to our south will sandwich the coastal waters causing an increased PG ahead of a cold front. This will result in worsening marine conditions at the start of the period as the front starts to move through, pushing offshore overnight Sunday. SW to W winds will gust +25 kts with seas rising to 5-7 ft. Behind the front, lighter N to NW winds will build in for Monday. High pressure moving overhead will lead to light and variable winds into Tuesday before another cold front moves through, possibly stalling in the area. Wind direction will be hard to nail at this time but wind speeds will be ~10-15 kts come mid week. Seas will be 1-3 ft behind the cold front moving through into Monday.

ILM WATCHES/WARNINGS/ADVISORIES

NC...None. SC...None. MARINE...Small Craft Advisory from 7 PM Saturday to 7 PM EST Sunday for AMZ250-252-254-256.