197
FXUS62 KCHS 291950
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
350 PM EDT Wed May 29 2024

.SYNOPSIS...
High pressure will build in from the west mid to late week,
passing overhead and then offshore over the weekend.

&&

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
A longwave mid-level trough will prevail over the East Coast.
At the surface, NW winds should become light or calm this
evening. A weak cold front will move through around midnight,
then quickly shift offshore. It`s dry so we won`t get any
precipitation and will only see a brief increase to partly
cloudy skies around its passage. Winds will veer to the NNW and
become light behind the front. Drier air building into our area
will cause dew points to fall into the upper 40s to lower 50s.
Along with cool air advection, we can expect decent radiational
cooling late tonight. Therefore, we went with the low end of
guidance. Lows will range from the mid to upper 50s far inland,
to around 60 degrees closer to the coast. At the beaches and
Downtown Charleston, warm water temperatures will keep air
temperatures from dropping as low as they could. These locations
should expect lows in the upper 60s.

&&

.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
A pseudo Omega blocking pattern will be in place across NOAM to
start the short term period with ridging from the southern
Plains into the Upper Midwest/western Great Lakes anchored by
troughs across western Canada/northwest U.S. through New England
and the mid Atlantic. Weak surface boundary and suppressed
upper level heights/cooler temps aloft will press down through
the southeast states for Thursday and Friday which will
translate into slightly cooler daytime temperatures with highs
running in the middle 80s (83- 87) although pretty close to
normal for late May. One more piece of stronger short-wave
energy is expected to dive from the Great Lakes and down into
and off the Mid Atlantic coast Friday, opening the door for
sharper upper level ridging to build through the southeast and
Atlantic coast region. Building heights and eventual southerly
return flow setting up across the region will trend temperatures
warmer through the weekend (and into next week). Overall...dry
weather prevails through the short term forecast period.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
Sharp upper level ridging and surface high pressure will slowly
transition off the coast late in the weekend/early part of the
next work week allowing a series of (largely) convectively
induced waves to ripple into and through the southeast and mid
Atlantic region, although deterministic longer term guidance
solutions show quite a bit of spread in the details. Warmer
temperatures return and this might open the door for a bit more
instability nosing out of the Gulf into the southeast from
Sunday onward. Blended model guidance continues to advertise low
end diurnal convection chances each afternoon through the long
term period, which is fine well inland but might be overdone
nearer the coast given model instability profiles/depiction.
Better chances across the coastal southeast may not be until
midweek. Nonetheless, for forecast consistency, and given
climatology heading into June, we have retained low end precip
chances each afternoon from Sunday onward.

Temperatures for the period start out in the middle 80s but
will be warming into the upper 80s to around 90 by midweek.
Overnight lows will span the 60s...warmer along the coast.

&&

.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
18Z TAFs: VFR.

Extended Aviation Outlook: Overall VFR conditions will prevail
through the period.

&&

.MARINE...
Tonight: Expect SW winds 5-10 kt this evening. A weak and dry
cold front will move through around midnight, then quickly shift
offshore. Winds will veer behind the front and surge due to
some cool air advection. Expect them to be NNW around 15 kt with
gusts to 20 kt by daybreak Thursday. Seas 1-2 ft this evening
will build to 2-3 ft overnight.

Thursday through Monday: No marine concerns through early next
week. High pressure initially centered to the northwest will
drift east and eventually offshore over the weekend. Wind speeds
average 15 knots or less. Seas will run 1-3 feet through the
period.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.
MARINE...None.

&&

$$

NEAR TERM...
SHORT TERM...Adam
LONG TERM...Adam
AVIATION...Adam
MARINE...Adam