Myrtle Beach, South Carolina 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

041
FXUS62 KILM 221115
AFDILM

Area Forecast Discussion
National Weather Service Wilmington NC
615 AM EST Mon Dec 22 2025

.SYNOPSIS...
Cooler temperatures are expected today as high pressure builds
in. Clouds increase early Tuesday as a warm front lifts
northward before another weak cold front passes Tuesday night.
Dry high pressure will dominate the area through the remainder
of the week with temperatures rising well above normal for late
December.

&&

.UPDATE...
Forecast on track for a sunny, but cooler day with northeasterly
winds. Aviation discussion updated for the 12z TAFs.

&&

.NEAR TERM /THROUGH TONIGHT/...
Any clouds associated with cold front will be shifting off the
coast as strong high pressure builds in from the north. Northerly
winds will usher in cooler air into the region and clear out
the sky. The 850 temps will drop about 5 degrees C with lows
dropping into the 30s early this morning and only rebounding
into the mid 50s this afternoon. High clouds will start moving
in this evening and coastal trough develops as high pressure
shifts off the coast. Shallow cool air overnight will be overrun
by the warmer moister air aloft and should see stratus develop
overnight before warm front lifts north by Tues morning.

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
Southerly flow on the western fringe of high pressure will
ensure a warm day on Tuesday. Mid level clouds associated with a
weak shortwave limping through southern VA and northern NC will
limit our warming potential. Highs generally in the low to mid
60s, warmer near the coast. Less cloud cover or an early
departure of the shortwave could push highs a little closer to
70 near the coast and in northeast SC. Fair conditions develop
late afternoon and early evening.

Boundary layer mixing will keep overnight lows in the low or
mid 40s with essentially neutral advection following a weak cold
front. Cold air advection eventually creeps into eastern NC on
Wednesday, but stops its southward advance near the NC/SC
border. Uncertainty in the progression of this cooler air
translates into uncertainties with highs on Wednesday. Ensemble
spread is larger for southeastern NC than northeastern SC. Some
of our SC communities could see temperatures a few degrees
warmer on Wednesday afternoon thanks to clear skies and ample
sunshine. Southeastern NC is bit more of a challenge at this
time due to the combination of the aforementioned cold air and
increased sunshine. Weak cold air advection may cut highs by as
much as 5 degrees. The current forecast (and NBM) maintain very
little change from the previous forecast due to this
uncertainty.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
Regardless of temperatures on Wednesday, the trend is upward
through the end of the week. Ridging aloft and surface high
pressure offshore will send temperatures into the 70s. Another
weak cold front will approach the area on Saturday. Copy and
paste the same uncertainties from Wednesday for Sunday as a weak
wedge attempts to build across the Carolinas. Similarly, the
warmer temperatures from the previous forecast have been
maintained for Sunday.

&&

.AVIATION /12Z MONDAY THROUGH FRIDAY/...
VFR conditions expected until the end of the TAF period, after
09z. Some cirrus will thicken after 20-22z and by 08-10z as warm
front lifts north, should see possibility of sub-VFR fog and
low clouds, as well as some stratocu around 5-6k ft.


Extended Forecast... Mainly VFR.

&&

.MARINE...
Through Tonight... A Small Craft Advisory remains in effect
through today. N-NE winds will increase to 15 to 20 kts with
gusts to 25kt as strong high pressure builds in behind exiting
cold front through today, diminishing through this afternoon. As
the high shifts off the coast tonight, a coastal trough will
develop with winds shifting around to onshore before turning
southerly by morning as it lifts north as a warm front. Seas up
to 3 to 6 ft on Mon will subside as winds diminish into late
Monday.

Tuesday Through Friday... Tuesday will start with light
southerly winds due to high pressure offshore. A cold front will
move through the region on Wednesday resulting in an increased
gradient and wind shift from SW to NW. Conditions should remain
below SCA thresholds in weak advection and poor mixing. Winds
weaken throughout the day on Wednesday as high pressure builds
into the Carolinas. High pressure traversing the region late
this week will lead to light and variable winds. Winds increase
on Friday ahead of the next weak cold front.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
NC...None.
SC...None.
MARINE...Small Craft Advisory until 6 PM EST this evening for AMZ250-
     252-254-256.

&&

$$

SYNOPSIS...ILM
UPDATE...RGZ
NEAR TERM...RGZ
SHORT TERM...21
LONG TERM...21
AVIATION...RGZ
MARINE...RGZ/21