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Office: CHS

FXUS62 KCHS 110220
AFDCHS

Area Forecast Discussion
National Weather Service Charleston SC
1020 PM EDT Wed Aug 10 2022

.SYNOPSIS...
High pressure will prevail tonight. A cold front will approach
Thursday into Friday, before pushing offshore early Saturday.
High pressure will briefly return early next week. Another
front could impact the region towards the middle of the week.

&&

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
Well that was an interesting evening. Remaining arcing line of
convection continues to move up through Allendale and Colleton
counties toward Dorchester county. Wind signatures within the
line have weakened considerably, at least in our CWA (nice wind
signature in Bamberg county at the moment). Will continue to
monitor convection as is presses on through the northern part of
the CWA.

Remaining showers/storms should dwindle in the next few hours
as daytime instability unwinds. Quite a bit cloud cover out
there per satellite imagery, and guidance/satellite trends
suggest we remain on the partly to mostly cloudy side through
the night, bolstered by our hazy Saharan dust layer that has
pressed in off the Atlantic. Overnight lows will run in the
lower to middle 70s inland to around 80 near the coast.

&&

.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
A mid level trough will amplify down the East Coast Thursday into
Friday. At the surface, high pressure will weaken as a cold front
approaches from the northwest. Models are pretty consistent in
showing the front passing through the area Friday night into early
Saturday. Better forcing and moisture will lead to at least
scattered showers and thunderstorms both days, with activity
possibly lingering into the overnight period as well. Friday looks
the most active with some pockets of heavier rainfall possible. The
threat for organized severe weather is low, but couldn't rule out a
couple stronger to possibly severe storms. Temperatures near normal
in the lower 90s on Thursday will fall a few degrees into the mid to
upper 80s for Friday. Lows mainly in the lower 70s Thursday night
will be in the upper 60s/low 70s for Friday night.

With the front progged to clear the area, Saturday should be quite
pleasant for late summer with drier air moving in as high pressure
rebuilds. Expect lower rain chances, plenty of sun, and cooler
temperatures with highs mainly in the mid 80s.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
A large mid level trough will reside over the eastern half of the
country during the early to middle of next week. At the surface,
high pressure will prevail, before another front possibly moves into
the area. Still some uncertainties on the evolution, but the pattern
could favor an increase in rain chances towards the middle of the
week. Temperatures will be near to slightly below normal.

&&

.AVIATION /02Z THURSDAY THROUGH MONDAY/...
Arcing line of showers and storms will move up through the
Georgia counties over the next few hours. Might clip the SAV
terminal area by 0030Z and I have included VCTS in the 00Z taf
forecast accordingly. CHS/JZI appear safe from any convection at
this juncture.

Additional showers and storms are possible again Thursday
afternoon and I have included VCSH in for all three sites.

Finally, a good amount of the Saharan Dust has spread off the
Atlantic into coastal SC and GA, resulting in a fair amount of
haze this afternoon and tonight. JZI is reporting 5sm in haze as
a result. Unclear how long the dust layer will be with us. But
there may be occasional reduced surface visibilities through
Thursday.

Extended Aviation Outlook: Prevailing VFR. Brief flight restrictions
are possible in afternoon showers/tstorms.

&&

.MARINE...
Through this Evening: Expect elevated winds along the land/sea
interface as the sea breeze moves inland, especially across the
Charleston Harbor. There could also be some showers and
thunderstorms with brief, strong wind gusts.

Tonight: Our area will be sandwiched between Atlantic High
pressure and an inland surface trough. The interaction between
these two features will cause a nocturnal jet to develop for the
first part of the night with SW winds around 15 kt. These winds
should ease a few kt before daybreak Thursday, and veer a
little bit in direction. Seas will peak in the 3-4 ft range.

Thursday through Monday: Southwest to west winds will prevail
through Friday ahead of an approaching cold front. The front will
pass offshore late Friday night or Saturday morning, flipping winds
around to the northeast/east for much of the weekend. Conditions are
expected to stay below small craft advisory criteria. Early next
week, winds will return to the south. Seas will average 2 to 3 feet.

Rip Currents: There is a Moderate Risk at all of our beaches
through this evening.

Lingering swell of around 2 feet every 8 seconds and
astronomical influences will lead to a Moderate risk of rip
currents on Thursday. The threat should decrease for Friday.

&&

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

&&

$$

NEAR TERM...TBA
SHORT TERM...ETM
LONG TERM...ETM
AVIATION...ETM/TBA
MARINE...ETM



Office: CAE FXUS62 KCAE 102329 AFDCAE Area Forecast Discussion National Weather Service Columbia SC 729 PM EDT Wed Aug 10 2022 .SYNOPSIS... High pressure offshore with weak surface trough across the area. Showers and thunderstorms are likely again on Thursday into Thursday night as a cold front moves through the area. Lower temperatures and humidity are expected during the weekend as high pressure builds in behind the front, continuing into early next week. && .NEAR TERM /THROUGH TONIGHT/... Offshore ridging remains in place despite the developing trough diving into the Great Lakes. Southwesterly low-mid level flow continues on the back of the surface ridge in the western Atlantic, and this is helping bring a few showers and storms towards the southern CSRA late this evening. Severe threat remains low with this activity, but can not rule out some gusty winds and brief heavy rainfall through 03z. Overnight lows in the low-mid 70's. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... Frontal boundary will continue pushing toward the region as upper level troughing also moves into the eastern US. Pwats will increase to around 2 inches through the day as SW flow increases however dynamics will be somewhat limited through the day. The best forcing will remain in the northern Midlands and Pee Dee then drift southward in the evening and overnight hours. The potential for severe thunderstorms remains limited however with some dry air remaining in the mid levels strong wind gusts will be possible. Have kept mention of showers and thunderstorms Thursday night as the moisture and frontal boundary combined with remaining instability and intersecting boundaries should keep a few cells going. By Friday morning the front will be across the southern half of the forecast area with drier air trying to push into the northern Midlands. Through the day Friday the frontal remains will continue sagging southward and becoming diffuse however will continue to be a focus for convection. Have kept the highest pops in the southern Midlands and CSRA with pops tapering to slight chance in the northern Midlands with the drier air. Potential for severe thunderstorms Friday again appears low due to limited dynamics with strong wind gusts still possible. High temperatures will be in the upper 80s to low 90s Thursday then in the mid 80s to around 90 Friday as cooler air tries to enter the region. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... High pressure will be moving into the eastern US as the remains of the front push further southward through the weekend. This will allow for an anomalously deep upper level trough to traverse the region. PWAT is expected to drop below one inch with dewpoints mixing out into the upper 50s and low 60s. Temperatures will also be below average and with the dewpoints make for some comfortable days with overnight lows in the 60s Saturday and Sunday nights. The next trough and weak frontal boundary will drop into the area early next week along with increasing chances of rain and temperatures returning to near normal. && .AVIATION /00Z THURSDAY THROUGH MONDAY/... VFR generally expected through the period. Convection has tended to be pretty muted across the region today, owing to southwesterly flow and limited instability from morning cloud cover. However, a fly in the ointment is developing a bit in the form of some organized convection across central Georgia. This is likely to at least continue into the CSRA, and has prompted me to put VCTS in at AGS and DNL through 03z this evening. I'll watch how the convection evolves over the next hour or two to determine whether restrictions need to be added within a TEMPO group. Outside of this, I don't anticipate restrictions occurring at the TAF sites tonight. The combination of another low-level jet and widespread upper level cloud cover should be enough to keep stratus and fog at bay. Winds will die down overnight and generally be between calm and 4 knots. By tomorrow, a cold front will begin approaching from the north and west. Moisture will increase a bit ahead of it, and we are expecting widespread cumulus to develop by midday. This will be VFR, but the expectation is that showers and thunderstorms will likely develop by 20-21z across the area. Confidence in timing and coverage precludes me from including VCSH or VCTS at this time. EXTENDED AVIATION OUTLOOK...Convection and possible restrictions expected Thursday as a front moves into the area. Moisture will linger through Friday so more restrictions possible. Drier air and no restrictions expected for Saturday and Sunday && .EQUIPMENT... KCAE radar has returned to operations. Temporary outages still possible this afternoon as any remaining problems are sorted out and calibrations performed. && .CAE WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. && $$ SYNOPSIS... NEAR TERM... SHORT TERM... LONG TERM... AVIATION... EQUIPMENT...
Office: GSP FXUS62 KGSP 110508 AFDGSP Area Forecast Discussion National Weather Service Greenville-Spartanburg SC 108 AM EDT Thu Aug 11 2022 .SYNOPSIS... High pressure over the area will slowly weaken tonight as a cold front approaches from the northwest. The front will move into the area on Thursday and settle south of the region by Friday, with an additional reinforcing cold front moving through from the north by Friday night. Cooler and drier high pressure will arrive for most of the weekend, but with moisture returning early next week. && .NEAR TERM /THROUGH TODAY/... As of 100 AM Thursday...Showers and thunderstorms from the Gulf Coast sea breeze continue to push northward across the fcst area this morning. Not expecting storms to become severe, but one or two could become strong with gusty winds and heavy rainfall the main impacts. Increased PoPs and PoTs overnight to account for this activity. High resolution models have been backing off on the fog potential, but went ahead added in some patchy mountain valley fog through daybreak as these areas have seen fog and low stratus the last few mornings. Another round of convection could make a run for the mtns ahead of the FROPA through daybreak. So, maintained chance PoPs across the mtns through the end of the forecast period. Another round of fog and low stratus could develop into daybreak across the NC mtns and foothills, although confidence is lower on this occurring with debris cloud cover over the CWA. The Charlotte metro area may also be under the gun for dense fog in the morning depending on how much of the debris cloud cover dissipates. Lows will remain around 3-6 degrees above climo. && .SHORT TERM /TONIGHT THROUGH SATURDAY/... As of 145 pm EDT Wednesday: A trof across the Great Lakes and Northeastern states will amplify late in the week pushing a cold front through the area. This front will lead to the chance of showers and thunderstorms well into the night on Thursday night, possibly lingering into early Friday in spots. Once the front clears the area on Friday, expect a slightly cooler and much more comfortable air mass for the weekend. Expect lows in the 50s Saturday morning in the mountains and in the lower to middle 60s in the Piedmont areas. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... As of 145 pm EDT Wednesday: The Northeastern trof will continue to amplify through this period leading to northwest mid level flow through the period. There will be some energy moving through the trof with associated cold fronts passing through the area. This will lead to a chance of showers and storms early next week, but overall moisture appears limited with this system. Temperatures should be near normal to a little below normal for Sunday into early next week. && .AVIATION /05Z THURSDAY THROUGH MONDAY/... At KCLT and elsewhere: Convection has diminished across the area with little chance of redevelopment thru the evening and overnight period at any TAF site. Plenty of debris clouds wafting in from the north, which may inhibit fog formation east overnight while KAVL and KHKY have a good chance of IFR or lower VSBY before daybreak. Afternoon convection develops ahead of a cold front and the better signals are noted across the NC zones, so have Prob30 TS at KAVL, KHKY, and KCLT into the later evening. Coverage and intensity looks more uncertain across SC so will go with a VCSH for now at these terminals. Winds remain aligned sw/ly ahead of front outside the mtns, while KAVL winds setup nw/ly thru the period. Outlook: Fog and low stratus may develop each morning in the mtn valleys and wherever appreciable rain fell the previous day. Shower and thunderstorm coverage, and associated restrictions, will increase along a cold front Thursday into early Friday. Drier conditions are expected this weekend behind the front. && .GSP WATCHES/WARNINGS/ADVISORIES... GA...None. NC...None. SC...None. && $$ SYNOPSIS...SCW NEAR TERM...AP SHORT TERM...SCW LONG TERM...SCW AVIATION...SBK