408
FXUS62 KILM 180503
AFDILM

Area Forecast Discussion
National Weather Service Wilmington NC
103 AM EDT Mon May 18 2026

.WHAT HAS CHANGED...
Coastal flood advisory for Inland New Hanover county has
expired. No coastal flood headlines are in effect.

&&

.KEY MESSAGES...
1) Inland portions of the eastern Carolinas should see their longest
heat wave of the year so far with 90 degree heat expected to
continue through Thursday.

2) Rain chances should increase, especially inland, beginning
Thursday as a front stalls near the Carolinas.

&&

.DISCUSSION...
KEY MESSAGE 1...Inland portions of the eastern Carolinas should see
their longest heat wave of the year so far with 90 degree heat
expected to continue through Thursday.

A 590 dam upper ridge centered near the North Carolina coast is
responsible for the sustained period of hot inland temperatures
which began today and should last through Thursday. Sinking air
below the upper ridge should create a deep warm and dry layer
extending down through 700 and 850 mb. Models have maintained
their 850 mb temp forecasts of +17C to 18C (at or above the 90th
percentile climatological values for this time of year) which
increases confidence in our forecast of 90+ degree heat
continuing through Thursday for locations more than 25 miles
inland.

Our forecast is for an additional four days (Monday through
Thursday) of 90+ degree heat inland. Assuming that Florence and
Lumberton highs touch 90 degrees this afternoon, this five day
streak would eclipse this year`s earlier streak of four days of 90
degree temps recorded from April 15-18 in both Florence and
Lumberton. Coastal portions of the Carolinas should remain
significantly cooler than inland due to sustained south winds
dragging air across nearshore water still near 70 degrees.

The upper ridge will become more narrow with time as an upper low
strengthens across the northern Bahamas Tuesday into Wednesday. This
feature looks a lot like an early season TUTT low, but any enhanced
convection or other sensible weather impacts should remain far to
our south. The arrival of a surface cold front Thursday afternoon
should end this heat wave with temperatures returning toward normal
for the coming weekend.


KEY MESSAGE 2...Rain chances should increase, especially inland,
beginning Thursday as a front stalls near the Carolinas.

A warm and dry subsidence inversion should keep the forecast
essentially dry through Thursday morning. Scattered showers and
thunderstorms could begin to develop inland as a cold front arrives
Thursday afternoon. Relatively cool and stable southerly winds may
help keep coastal areas dry.

An interesting dichotomy develops among model guidance late in the
week about how widespread convection may become across the
area. GFS MOS guidance rain chances have really come down and
confine any PoPs better than about 40 percent to the
Elizabethtown-Lumberton-Bennettsville corridor close to where
the front may stall Thursday night through Friday. South and
east of this area PoPs are generally in the 20-40 percent range
given lingering ridging and some dry air aloft. However
ensemble-based NBM PoPs are much, much higher and would imply
high rain chances (60-70 percent) Friday, Saturday, and Sunday
even down near the coast.

Model trends have been toward somewhat lower rain chances,
especially at the coast, and I ultimately lean toward that idea.
This should still be our best rain chance in almost a week, but
significant rainfall chances will likely remain inland.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
VFR conditions this evening.

Fog chances increase tonight with more humid low levels observed
across the region today. Kept most of the fog east of I-95 and
just inland from the coast where boundary layer winds will be
higher. This puts southeast NC at a better chance of more
significant restrictions overnight. Only exception was to
maintain persistence at CRE from last night`s tidal creek fog.

Sea breeze should dominate after noon with gusts to 20 knots
at the coast, mid-afternoon inland.

Extended Forecast... Predominantly VFR through Wednesday though
morning fog potential should increase through Wednesday as low level
moisture increases.  An approaching front could bring restrictions
in scattered showers and storms Thursday and Friday.

&&

.MARINE...
Through Monday...Within 20 NM, light S TO SE winds are expected
through period with seas of 2 to 3 feet.

From 20 to 60 NM out, generally expecting s winds less than 15 KT
with seas of 3 feet.

Monday night through Friday...Bermuda high pressure will remain over
the western Atlantic through the period with generally light
southerly winds expected. Seabreeze enhancement nearshore could
locally increase nearshore wind speeds to around 15 knots from mid
afternoon through early evening each day. A cold front will approach
from the north Thursday night into Friday, but only a subset of the
latest models show the boundary actually reaching the coastal
waters. What may happen is southerly winds will back more
southeasterly on Friday with some increase in the potential for
showers and thunderstorms. Forecast confidence for Friday is
certainly lower than for Monday night through Thursday.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
NC...None.
SC...None.
MARINE...None.

&&

$$

WHAT HAS CHANGED...TRA/21
KEY MESSAGES...TRA
DISCUSSION...TRA
AVIATION...21
MARINE...TRA/31