Area Forecast Discussion
Issued by NWS Wilmington, NC
Issued by NWS Wilmington, NC
593
FXUS62 KILM 190001
AFDILM
Area Forecast Discussion
National Weather Service Wilmington NC
801 PM EDT Tue Aug 18 2026
.WHAT HAS CHANGED...
The Heat Advisory continues for Wednesday. Updated 00Z TAF
discussion.
&&
.KEY MESSAGES...
1)Dangerous heat to continue for several days.
&&
.DISCUSSION...
KEY MESSAGE 1... Dangerous heat to continue for several days.
An area of low pressure off of the northeastern US coast which
aided in downslope heating will push off to the north and east
on Wednesday. The elimination of the downslope component will
allow low level thicknesses to increase. Surface temperatures
decrease by a few degrees as a result. More importantly, coastal
areas should see a marginal benefit from the afternoon sea
breeze. Cooling from the sea breeze will compete with increase
dew points, so heat indices will only be marginally improved;
down from the Extreme Heat Warning threshold in previous days.
Mixing for inland areas should allow dew points to push heat
indices below heat headline criteria. A Heat Advisory has been
issued for coastal northeastern SC and areas east of I-95 in
southeastern NC.
A weak frontal boundary along the NC and SC coast will assist
the afternoon sea breeze and provide a more focused area for
weak ascent on Wednesday afternoon. Areas west of I-95 will be
limited by dry air aloft, but pooling PWs east of I-95, along
with a progressing sea breeze and surface thermal low should
produce isolated to widely scattered showers and thunderstorms.
By late this week, heights will start to rise in the west and
some weak troughiness will develop in the east but not of
sufficient strength for any heat-breaking frontal passages.
Highs in the mid to upper 90s are expected to continue until
Friday. These readings paired with dewpoints in the mid to upper
70s and occasionally low 80s will necessitate heat-related
headlines each day. The only nuance will be which days will
bring lower dewpoints down over inland zones where an advisory
will be sufficient (HI values of 105- 109) and how much of the
eastern CWA will requite a warning (HI values of 110 or higher).
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
Predominant VFR. Question will be for MVFR fog tonight. Highest
chances if any will be at KLBT and perhaps KILM, but formation
shouldn`t be until late (06-09Z) so additional confidence might
come with the 06Z issuance. Even if VSBYs dip to MVFR
restrictions may be brief/on and off. Then into Wednesday
PROB30s have been included for afternoon convection at terminals
with highest confidence.
Extended Forecast... VFR conditions are expected much of the
week outside of any convection. Rain chances increase on Friday
with afternoon convection possible through the weekend.
&&
.MARINE...
Benign conditions expected for most of the period. Weak surface
flow turns SW to light and variable overnight. Expect a period
of light onshore flow Wednesday. Thereafter a more typical SW
flow returns as the boundary washes out but wind speeds will
remain very tame even by late summer standards. The approach of
a front could lead to a slight inc in winds and seas Saturday. A
SE swell will be coincident with the wind waves through the
duration.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
NC...Heat Advisory from 11 AM to 8 PM EDT Wednesday for NCZ096-099-
105>110.
SC...Heat Advisory from 11 AM to 8 PM EDT Wednesday for SCZ054>056-
058-059.
MARINE...None.
&&
$$
WHAT HAS CHANGED...ILM
KEY MESSAGES...MBB/21
DISCUSSION...MBB/21
AVIATION...LEW
MARINE...MBB