Area Forecast Discussion Issued by NWS Wilmington, NC
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000
FXUS62 KILM 271930
AFDILM
Area Forecast Discussion
National Weather Service Wilmington NC
330 PM EDT Wed Mar 27 2024
.SYNOPSIS...
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A strong storm system will produce moderate to heavy rain late
today through early Thursday. Dry high pressure then builds in
Thursday night with a warming trend and dry weather through the
weekend. Another frontal system approaches early next week,
bringing the next chance for rain late on Tuesday.-- End Changed Discussion --
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.NEAR TERM /THROUGH THURSDAY/...
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A cold front parked just west of I-95 will be the focus for showers
and thunderstorms this evening. Radar currently shows light showers
developing along this boundary (as of 3 PM EDT). Elevated
instability will bring the potential for small hail and heavy rain
as these showers mature and lift becomes more organized. For a brief
period late this afternoon and early this evening, low level lapse
rates could improve enough to bring gusty winds to the surface in
stronger showers and storms. A wind gust up to 30-40 mph is
possible.
The cold front will start to drift eastward late this evening and
overnight. The axis of heavy rain will follow the surface front from
west to east. Minor flooding is possible where showers or
thunderstorms develop into a training line of heavier rain. This is
not expected to be a widespread hazard although reduced visibilities
and ponding on roadways could impact travel. Small hail may also be
observed in stronger updrafts.
Instability shifts eastward with the surface front on Thursday
morning with lingering showers and storms possible along the coast.
Showers become lighter in intensity as dry air infiltrates aloft by
early morning, working its way from west to east with the front.
Light showers may persist into the early afternoon along the coast,
mainly in southeastern NC.
Breezy on Thursday behind the front. Boundary layer momentum transfer
may exceed 35 mph in a few spots during the afternoon. Higher winds
will likely be along the coast and in southeastern NC with the best
gradient. Wet soils and strong winds could lead to some isolated
power outages and downed trees. Cool with highs around 60.-- End Changed Discussion --
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.SHORT TERM /THURSDAY NIGHT/...
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Rain should be over by the start of the period (00Z/29) with the
shortwave trough axis passing overhead and moving offshore
around or shortly after 00Z. The passage of this trough axis
will lead to increasing subsidence while low-level moisture
scours out during the overnight. Decreasing sky cover and
cold/dry advection via NW winds will modulate low temperatures,
with mainly low 40s expected, although some upper 30s cannot be
ruled out in normally cooler spots such as sheltered locations.-- End Changed Discussion --
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.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
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High pressure centered over the northern Gulf Coast will shift
off the southeast US coast on Friday night and take up a
position north of the Bahamas for the weekend. This will set up
a warm southwesterly low-level flow over the weekend which will
combine with rising 1000-500mb thicknesses and mainly sunny
skies to bring a substantial warming trend to the region. Highs
are expected to rise from around 70F on Friday to around 80F on
Sunday while lows rise from the 40s on Friday night to near 60F
on Sunday night. A subtle mid-level ridge axis will shift
across the area over Monday night into early Tuesday, with the
warmest temperatures of the period expected on Monday (low 80s),
although thick high-level clouds are expected to spill into the
area and limit heating on Monday and Tuesday.
After another abnormally warm day on Tuesday, rain chances
return for Tuesday night and Wednesday as shortwave energy and
an associated cold front approaches. Confidence is low on the
timing and evolution of this mid-level energy, which will
determine the duration and intensity of any rain it brings. With
the main troughing staying to our north, the typical
expectation is for a decaying band of showers to accompany the
front. However, if a frontal wave develops along the front, this
could enhance precipitation totals. Given this is near the end
of the period, there is plenty of time for guidance to come into
better agreement in the coming days.-- End Changed Discussion --
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.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
VFR in warm advective flow along the coast and most of our
inland areas east of I-95. Other than some passing showers which
will bring MVFR, expect this to continue into this evening.
Inland, MVFR seems to be dominant near the leader edge of a
stalled cold front near I-95. As this front creeps eastward this
evening, MVFR will gradually worsen to IFR behind the front.
Heavy rain and elevated instability will lower VIS at all sites,
progressing from west to east this evening and after midnight.
LIFR in heavy rain behind the front will improve slightly after
sunrise tomorrow morning although heavy rain may continue
through mid morning. Winds out of the SE this afternoon and
this evening will be gusty before turning light and variable
during the front`s passage, becoming northerly behind the front.
Extended Outlook...Flight restrictions likely into Thursday
with increasing rain chances. Forecast dries out Thursday night
and high pressure returns throughout the weekend, allowing for
widespread VFR.
&&
.MARINE...
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Through Thursday... Southeasterly winds this evening will gradually
increase and become southerly as a surface cold front to the west
drifts eastward overnight. The gradient maximizes behind the cold
front early Thursday. Cold air advection over the waters will bring
gusts to SCA thresholds with all waters seeing sub-Gale gusts by mid
morning. Winds peak during the mid afternoon and gradually improve
tomorrow evening. Given the short burst of winds and limited fetch,
steep seas peak on Thursday around 4-6 feet.
Thursday night through Monday... Weakening offshore flow behind
a cold front will contribute to subsiding seas early in the
period, with waves expected to fall below 6 feet in the NC
waters around midnight Thursday night. With broad high pressure
shifting to our south on Friday, winds will back to westerly on
Friday and then to southwesterly Friday night and remain
southwesterly through Monday. A somewhat tighter pressure
gradient due to a storm system passing well to our north may
lead to SCA-level wind gusts late on Saturday into Saturday
night, but this would be a marginal SCA at worst. With high
pressure centered north of the Bahamas through the period, wave
heights will remain in the 2-4 ft range, with southwesterly wind
waves being the primary contributor to the wave spectrum.-- End Changed Discussion --
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
NC...None.
SC...None.
MARINE...Small Craft Advisory from noon Thursday to 4 AM EDT Friday for
AMZ250-252-254-256.
&&
$$
SYNOPSIS...ILM
NEAR TERM...21
SHORT TERM...ABW
LONG TERM...ABW
AVIATION...21
MARINE...21/ABW