Area Forecast Discussion Issued by NWS Wilmington, NC
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000
FXUS62 KILM 071053
AFDILM
Area Forecast Discussion
National Weather Service Wilmington NC
653 AM EDT Wed Jun 7 2023
.SYNOPSIS...
A chance for storms persists this afternoon and this evening
ahead of a cold front. After a brief cooldown Thursday,
temperatures will climb back to normal through the remainder of
this week. The next cold front will move into the area early
next week, and will bring better rain chances Monday.
&&
.UPDATE...
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Added haze for the entire area in line with the currently
active Air Quality Alert. Updated PoPs slightly to nudge down
afternoon storm chances and move them a couple hours later in
the day. Best chance of precip will come this evening with the
main cold front, but instability will be limited at this point.-- End Changed Discussion --
&&
.NEAR TERM /THROUGH TONIGHT/...
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A cold front currently analyzed just north of the NC/TN border
will continue to drop southward with a deepening upper level low
this morning. As the front approaches the area this afternoon,
surface based and mid level forcing working in conjunction with
instability will generate isolated to scattered storms. Showers
with embedded shallow convection are possible with the main
cold frontal passage this evening.
Instability gradients from north to south will put the focus of
storms at initialization along the coast (better chance along
the SC coast) and parts of eastern SC this afternoon. Sea breeze
showers and storms will be possible during the early afternoon,
but likely be isolated. Near surface dew point depressions
remain large for meaningful coverage of sea breeze showers and
thunderstorms. Surface temperatures are likely to top out near
90 inland with upper 80s along the coast. Dew point in the low
60s and upper 50s inland after early day mixing.
Storm chances increase to the north then inland through the
afternoon as the initial trough ahead of the cold front
approaches the area and instability peaks. SPC continues to
highlight a Marginal Risk (Level 1 of 5) for the coast and
eastern SC. This is mainly for the potential of downdrafts
highlighted again by DCAPE above 1000 J/kg. With weak
unidirectional shear throughout the day and a dramatic north-
south instability gradient, this threat should remain low and
localized as the afternoon progresses.
As the main cold front approaches the area this evening, low
level convergence and increasing moisture advection aloft should
support a line of showers. No significant impact is expected
with this line of showers. Cold air advection will follow late
tonight, bringing temperatures into the low to mid 60s. Some
uncertainty with tonight`s lows due to the potential for low
clouds and increasing northerly winds behind the front; have
blended some NAM with NBM to capture the potential for higher
cloud fraction.-- End Changed Discussion --
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
Forecast looks to initially dry out a bit Thursday morning,
with the front located well to the south of the area. However,
one last push from a shortwave associated from the upper low in
New England will provide enough vorticity to spawn a weak
surface low along the frontal boundary. This increases rain
chances by Thursday afternoon, particularly in northeast SC
(south of the Pee Dee and Grand Strand). Showers in these areas
should be brief and on the faster side. Last of the shortwave
pushes offshore Thursday night, with the parent low finally
moving stage right and out of the picture. This eliminates the
shower chances throughout the night. Cooler air comes in, with
highs only hitting the low 80s, and some chilly (for June) lows
in the upper 50s. Dewpoints also crash into the 50s. Pumpkin
spice weather?
Friday, surface high pressure from the upper Midwest quickly
slides southeastward. Weak WAA sets up, allowing highs to be
about 1-3 degrees warmer from the previous day. Clear skies
Friday night allow lows pretty similar from the night before.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
Summer finally decides to show up over the weekend. Plenty of
sunshine expected, with highs in the mid-to-upper 80s Saturday
increasing to the upper 80s to near 90 on Sunday. Lows will see
a similar trend, going from the mid 60s Saturday night to the
upper 60s on Sunday night. Plenty of sunshine ahead!
By the beginning of next week, another upper low over the Great
Lakes moves into the northeast, which will help to spawn a
surface low over the Ohio River Valley. As the surface low moves
northward, it`ll drag a warm front through the Carolinas
Monday, spiking the moisture through the atmospheric column.
With good frontal lifting in place, Monday looks increasingly
showery, with rain chances increasing with each forecast update.
Clouds and rain keep highs in the mid-to-upper 80s Monday and
Tuesday, with a cold front moving through the area Monday night
into Tuesday. Forecast guidance still differs on the location
and intensity of the upper low driving this mess, so future
forecasts will better tell the story.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
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Mainly VFR. A good chance of convection along the coast this
afternoon, have focused any PROB30 flight restrictions in SC
during the late afternoon. Showers approach in a line this
evening, likely impacting all sites from north to south after
03Z through early Thursday. MVFR/IFR possible late tonight
behind the front in low clouds, but confidence is low.
Extended Outlook...Mainly VFR conditions through Saturday.-- End Changed Discussion --
&&
.MARINE...
Through Tonight...SW winds increase today ahead of a cold front
with the potential for thunderstorms right along the coast this
afternoon. Storm chances increase over the water tonight ahead
of the front as winds become offshore and NW behind the front.
Winds ahead of the front will be much more noticeable at 15-20
knots than behind the front at around 10 knots. Seas 3-4 feet
this afternoon, becoming 2-3 feet this evening outside of any
showers or storms.
Thursday through Sunday...Even with the front well to the south
by Thursday, a weak surface low forming along it keeps somewhat
variable SW to NW winds at 5-10kts Thursday and Friday, with
seas lingering at 1-2ft. Winds at 10-15kts go more southerly by
Saturday, with high pressure setting up some return flow. Seas
increase to 2- 3ft by this point, with winds developing more of
a southeasterly tilt by Sunday.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...None.
NC...None.
MARINE...None.
&&
$$
SYNOPSIS...ILM
UPDATE...21
NEAR TERM...21
SHORT TERM...IGB
LONG TERM...IGB
AVIATION...21
MARINE...IGB/21