textproduct: NWS Wilmington

WHAT HAS CHANGED

Aviation discussion updated for the 18Z TAFs.

KEY MESSAGES

1) Potential Record-Tying or Breaking Temperatures Expected Saturday, With Fire Weather Hazards Continuing.

2) A strong cold front, accompanied by scattered showers, and isolated thunderstorms, is expected to move from west to east across the area during Sunday morning, before shifting off the coast by early afternoon and to well offshore by late afternoon. A period of slightly below normal temperatures is expected to follow Sunday night through Tuesday night.

DISCUSSION

KEY MESSAGE 1...Potential Record-Tying or Breaking Temperatures Expected Saturday, With Fire Weather Hazards Continuing.

The subtle front (such that it is) is starting to push offshore as of this typing (2 PM EDT). Accompanying shortwave aloft will follow within the next few hours. Calm tonight, with lows in the low-to-mid 60s.

Mid-level ridging builds up Saturday, allowing for temperatures to get just a little bit warmer. Record-tying or breaking high temperatures expected, especially inland. Here's a look at the current records across the area for April 18:

Wilmington, NC (KILM): 93 in 1976 North Myrtle Beach, SC (KCRE): 89 in 1967 Florence, SC (KFLO): 93 in 1981 Lumberton, NC (KLBT): 91 in 1941

A little more moisture builds into the column Saturday, allowing for a few cumulus clouds to pop up at 6000-8000 ft. Other than that, extremely dry weather continues. Diurnal mixing looks to go up towards 7000-8000 ft, which brings the dewpoints down at the surface. Ultimately, this brings the afternoon RH values down to 25%.

Regardless of where the RH is, severe to extreme drought continues across the Carolinas, with a burn ban in effect until further notice for everyone. Saturday won't be particularly breezy, but everything outside is a tinder box at this point.

KEY MESSAGE 2...A strong cold front, accompanied by scattered showers, and isolated thunderstorms, is expected to move from west to east across the area during Sunday morning, before shifting off the coast by early afternoon and to well offshore by late afternoon. A period of slightly below normal temperatures is expected to follow Sunday night through Tuesday night.

H5 trough moving across the Eastern U.S. on Sunday will drive a sfc cold front across the forecast area, and off the mainland to well offshore during Sunday afternoon. POPS for scattered showers and isolated thunderstorms remain in the 20 to 40 percent range. Only isolated thunderstorms possible given the weak tstorm parameters progged. Limited moisture will also result in QPF less than 0.10 inches, which this may even be too high. This will not even satisfy the thirst of the vegetation of the ongoing growing season. In essence, the severe/extreme drought across portions of Southeast NC and Northeast SC will continue to worsen.

In the wake of the cold frontal passage, CAA under gusty NW-NNE winds will overspread the area Sun afternoon and night becoming neutral advection Mon. The end result will see below normal temperatures overspreading the area Sunday night and continuing thru Tuesday night. This time of year, normal highs are in the mid to upper 70s and normal lows in the lower 50s. The sheltered/cold spots could drop down into the upper 30s for lows early Tuesday morning given winds possibly decoupling up to several hrs prior to sunrise. Temperatures will rebound back above normal Wednesday thru the end of the upcoming work-week. And with continued dry conditions with no pcpn in the forecast.

AVIATION /19Z FRIDAY THROUGH WEDNESDAY/

Nothing but VFR for the 18Z TAF period. Seabreeze winds may get up to near 12 kts at times for KCRE and KMYR this afternoon, but otherwise, winds will be light and variable for the other terminals. Winds calm soon after sunset tonight. Look for SSW winds to pick up a bit towards the end of the period, especially at the coast with the seabreeze once again. May have a few cumulus at 6000-8000 ft.

Extended Forecast...VFR through Saturday night and Sunday morning. Isolated showers and thunderstorms may accompany a cold frontal passage Sunday afternoon. Northerly winds behind the front could gust to 25 knots Sunday afternoon into Sunday night. Otherwise VFR conditions should prevail through Wednesday.

MARINE

Through Saturday...Moderate breeze out of the southwest at 10-15 kts expected through Saturday. Seas at 2-4 ft out 20 nm from shore expected through this evening, with 4-5 ft seas possible up to 60 nm from shore. Overnight tonight, seas decrease to 2-3 ft everywhere.

Saturday Night through Tuesday Night...Looking at SW winds increasing Sat night into Sun from both a LLJet with 25-30 kt SW winds just off the deck up to 925mb and a tightening sfc pg ahead of the approaching cold front from the west. Expanding/pivoting upper trof extending from Hudson Bay will help drive the cold front to the Carolina Coasts by midday Sun and to well offshore by late afternoon/early evening. Will see scattered convection accompanying it, further blossoming as the activity reaches the warmer Atl waters. Looking at a decent windshift, from SW-NW then to the NNE-NE at SCA thresholds Sun night as sfc ridging builds in from the west behind the departing cold front. The gradient relaxes during Mon with winds diminishing below SCA thresholds. The upper trof's axis will swing across the area late Mon, allowing for a secondary CFP Monday evening accompanied with less fanfare than its predecessor. Sfc high to follow and ridge in from the north Mon night thru Tue.

ILM WATCHES/WARNINGS/ADVISORIES

NC...Coastal Flood Advisory from 9 PM this evening to 1 AM EDT Saturday for NCZ107. SC...None. MARINE...None.