504
FXUS62 KCHS 021914
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
314 PM EDT Thu May 2 2024

.SYNOPSIS...
Atlantic high pressure will remain across the Southeast through
much of next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
Tonight: A few transient, light sprinkles have been observed
on KCLX this afternoon along a well defined pure sea breeze
circulation. No measurable rainfall has been observed so far and
none is expected. Gridded pops were still held below
mentionable thresholds. The sea breeze will continue to march
inland for the rest of the afternoon, likely clearing the far
inland areas by mid-evening.

The main forecast issue for the overnight is trying to pin down
the extent and location of fog and stratus. The airmass as
changed little in the past 24 hours and with the synoptic
pattern nearly identical to last night, conditions appear
favorable for another round of dense fog late this evening into
the morning hours Friday. Interestingly, the 12z guidance
members are giving number of possible fog scenarios ranging from
widespread dense fog just about everywhere to only patchy,
shallow ground fog with no major reductions in visibility.

The forecast favors the foggier solutions with NBM probabilities
for dense fog ranging from roughly 50-80%, highest over Southeast
South Carolina. This is where the afternoon dewpoint footprint
is the highest and the best overlapping of the lowest RAP/NAM/H3R
1000 hPa condensation pressure deficits are progged. Areas fog
with patchy dense fog areal qualifiers were highlighted for all
but interior Southeast Georgia from roughly Reidsville-Millen
where fog parameters will not be as ideal. It is very possible
another Dense Fog Advisory may be needed for some areas later
tonight and this possibility is well outlined in the Hazardous
Weather Outlook. Lows tonight will range from the mid 60s well
inland to around 70 at the beaches and Downtown Charleston.

&&

.SHORT TERM /FRIDAY THROUGH SUNDAY/...
Mid level ridge axis transitions off the Southeast coast Friday
with shortwave energy to move through the region over the
weekend. High pressure will remain the primary feature at the
surface. A few showers and thunderstorms could sneak into inland
areas Friday, but convection should be a bit more active over
the weekend. Coverage will be highest in the daytime when
instability is maximized, but with some upper forcing in play
activity will be possible overnight as well.

High temperatures generally peak in the mid to upper 80s. Lows
only drop to the mid to upper 70s.

&&

.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
Atlantic high pressure will persist during the early to middle
of next week. Convection looks to be most active early in the
period, then the chances for showers/thunderstorms decrease
towards mid week as ridge rebuilds overhead. Temperatures will
also be creeping up, possibly approaching record levels by
Wednesday/Thursday.

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
02/18z TAF Discussion:
KCHS/KJZI/KSAV: The main concern is on fog/stratus overnight
into early Friday morning. 12z guidance is trending lower with
both vsbys and cigs later tonight as a warm/moist airmass
remains in place. Synoptically, the pattern will be similar to
last night, so guidance is likely trending in the right
direction. The 18z TAFs for all three terminals will highlight
conditions dropping below each airfield`s respective alternate
minimums by 08z with conditions occasionally dropping right to
or just below airfield minimums in the 09-13z period. It is very
possible all terminals may become completely fogged in early
Friday with vsbys 1/4SM and VV001-002. The need to introduce
lower conditions will be reevaluated with the 00z TAF cycle, but
a lower trend has been initiated with this TAF cycle. VFR should
quickly return once fog/stratus mix out Friday morning, roughly
in the 13-14z period.

Extended Aviation Outlook: Flight restrictions possible in
overnight/early morning fog and stratus. Isolated to scattered
showers and thunderstorms are possible Saturday through Monday.

&&

.MARINE...
Tonight: East to southeast winds will prevail tonight with high
pressure centered well offshore. Fog could become an issue in
the Charleston Harbor as fog oozes into the harbor from nearby
areas. The fog could become locally dense with vsbys <1NM. A
Marine Dense Fog Advisory could be needed at some point
overnight. Fog could impact harbor operations in the Charleston
Harbor and Port of Savannah. The fog could not be too much of a
concern over the Atlantic coastal waters given the onshore flow
regime that is in place. This should limit the fog to areas
inland from the beaches. Wind speeds will average less than 10
kt with seas 1-2 ft.

Friday through Tuesday: No marine concerns. Atlantic high
pressure will maintain rather benign conditions over the marine
area. Winds are generally no higher than 10-15 kt with seas 2-3
ft.

&&

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

&&

$$