439
FXUS62 KCHS 101347
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
947 AM EDT Fri May 10 2024

.SYNOPSIS...
A cold front will push offshore today. High pressure will
prevail for the weekend into early next week. A storm system
could affect the area by the middle of next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
This morning: A large area of mostly stratiform rain and
embedded weakening convection continues to track eastward across
the forecast area. We have cancelled all of the Severe
Thunderstorm Watch, except for McIntosh County which is closest
to the best available instability. Overall, the severe threat is
rapidly diminishing, even for McIntosh County. The area of
stratiform rain is also steadily shrinking, and potential
rainfall amounts through late morning continue to diminish. By
around midday or so, the stratiform rain should dissipate
completely and we should be rain-free by the early afternoon.
Attention then turns to the upstream cold front and isolated to
scattered convection that should develop along it across the
Midlands. This activity could then track into portions of the
forecast area late this afternoon and into the early evening.
With the widespread cloud cover and rainfall moving through the
area currently, it seems unlikely we will be able to recover and
destabilize sufficiently to produce much of a severe weather
threat this afternoon and evening. If there is an area with a
risk, it would be the Charleston Tri-County area and Colleton
County. High temperatures will be tricky and warming will be
delayed due to the ongoing rainfall and cloud cover. We still
think low 80s for highs is on track.

The cold front is timed to push off the coast by midnight. In
the wake of the front, winds should shift from the north with
steady CAA. Given ongoing CAA through daybreak Saturday, low
temperatures are forecast to generally range from the mid 50s
inland to around 60 along the coast.

&&

.SHORT TERM /SATURDAY THROUGH MONDAY/...
Saturday and Sunday: Broad troughing will prevail aloft through
the weekend, with high pressure building in at the surface.
With high pressure dominating at the surface, the weekend will
feature a rather benign weather pattern. Temperatures on
Saturday will actually be much cooler than the previous week,
owing to FROPA on Friday night. Highs on Saturday are forecast
to peak in the mid to upper 70s. Sunday will be slightly warmer,
with highs in the low 80s. Sunshine will be plentiful,
accompanied by a rain-free forecast.

Monday: The upper level pattern shifts a tad on Monday, with
models indicating a few shortwave troughs could ripple across
the forecast area. This could provide enough forcing for
isolated to scattered showers and thunderstorms. Temperatures
are forecast to reach into the upper 70s to low 80s.

&&

.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
Beginning Monday night the forecast turns more active as a warm
front approaches the forecast area from the south. Aloft, a
mid-level trough is forecast to swing through the southeastern
states through Thursday. MOisture is expected to build into the
region after the warm front lifts northward, with PWATs
approaching 2". Several rounds of showers and thunderstorms are
expected as the region remains well within the warm sector with
plentiful moisture, aided from the approaching mid-level trough.
Temperatures are expected to gradually warm through the period,
with upper 70s to low 80s on Tuesday warming to the mid to
upper 80s by Thursday.

&&

.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
Prior to the 12Z TAFs, IR satellite indicated widespread debris
clouds across the terminals. The main challenge will be the
timing and intensity of MCS, located over southern AL and MS
before 12Z TAFs. Based on the majority of the CAMs, the core of
the MCS track along the FL/GA this morning. A band of showers
and thunderstorms on the north side of the MCS is timed to pass
over KSAV, expected between 13-17Z. The KSAV TAF will feature a
mention of SHRA with VCTS between 13-17Z, with a TEMPO for TSRA
from 14-17Z. KCHS and KJZI, the coverage TSRA will remain
limited, the TAFs will feature TEMPOs for TSRA between 14-16Z.
Late in the afternoon, a narrow band of showers and
thunderstorms will develop along a cold front west of the
terminals. After sunset, the coverage of showers and
thunderstorms will decrease as the front approaches the
terminals. The cold front is time to pass over the terminals
between 3-4Z, turning winds from the NW at 10kts.

Extended Aviation Outlook: VFR conditions will prevail through
the weekend. Showers and thunderstorms could bring flight
restrictions to the terminals Monday afternoon into the middle
of next week.

&&

.MARINE...
A line of thunderstorm could push across the GA waters this
mornings. These storms may yield wind gusts in excess of 35 kts,
Special Marine Warnings may be issued. Otherwise, winds should
remain from west-southwest between 15-20 kts. Wave heights are
forecast to range between 3-4 ft. This evening, a cold front
will approach from the northwest, timed to reach the coast
around midnight. The front should rapidly sweep across the
marine zones, turning winds from the north. Speeds will favor
values between 15 to 20 kts, gusts could reach 25 kts at times.
Seas will change very little overnight, remaining between 2-4
ft.

Saturday through Wednesday: Generally tranquil marine
conditions are forecast through the weekend as high pressure
extends over the local forecast area. Winds will generally be
around 10 knots, with seas averaging 1 to 2 feet. Monday night S
to SE winds will surge slightly as a warm front lifts northward
through the region, generally around 15 knots with some gusts
around 20 knots. Seas will also increase, averaging 3 to 4 feet.
These conditions will persist into the middle of the week.

&&

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

&&

$$

NEAR TERM...BSH/NED
SHORT TERM...CPM
LONG TERM...CPM
AVIATION...CPM/NED
MARINE...CPM/NED