Special Weather Statement, NWS Greenville-Spartanburg, SC

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
534 PM EDT Sat Apr 24 2021

.SYNOPSIS...
A low pressure system will track into the Carolinas this evening,
bringing shower and thunderstorm chances. An isolated severe storm
cannot be ruled out across the southern portion of the area. Rain
chances will gradually decrease overnight as the low pressure system
tracks off the Mid-Atlantic coast. Canadian high pressure fills in
behind the departing front on Sunday. This high pressure system will
remain in place in the early to middle part of next week, leading to
gradually warming temperatures and drier weather. Another cold front
impacts the area late next week and increases rain chances again.

&&

.NEAR TERM /THROUGH SUNDAY/...
As of 530 pm EDT: The surface boundary draped across the southeast
tier of the forecast area has worked just far enough north late
today to uncover some lower 60s dewpoints. The resulting surface-
based instability appears to be getting uncovered just in time for
the next round of forcing tracking northeast with the surface wave
riding from central GA into the forecast area by 23Z-00Z. PoPs early
this evening, and southern tier thunderstorm chances south of the
wedge boundary, have been boosted. Isolated severe thunderstorms
remain possible - although instability should not be as stout as in
areas farther southwest near ATL where warnings currently exist. he
other adjustment to the forecast is slower diminishment of the
precipitation overnight as the wave and associated moisture are a
bit slower to clear the area on the latest near-term guidance. Will
thus feature better early night PoP, more overnight clouds, and also
warmer mins with this trend.

Otherwise, PoPs should taper off early AM Sunday, lingering longest
along the TN border, as flow turns out of the NW in the wake of the
passing sfc low. Drying aloft with moist low-levels does spell a low
stratus and/or fog threat. But the passing low and onset of dry and
cold air advection should limit this somewhat.

Sunday looks like a really nice day, as high pressure builds in
across the Southeast under west-northwesterly flow aloft. Temps
will be near to slightly below normal under sunny skies, except
lingering cloudiness along the TN border. It will be a bit breezy
early in the day, especially in the mountains, but with winds
becoming a little weaker in the aftn.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
As of 1244 PM Saturday: The first part of next week looks
exceedingly quiet...as the upper pattern remains slowly progressive
while amplifying into the middle of the week. Sfc high pressure
will move past Sunday night and Monday as the axis of an upper
ridge approaches from the west. Temps will start out close to
normal, but will gradually warm through Tuesday and Wednesday as
the upper ridge axis moves overhead and pushes the sfc high off
the East Coast. The pattern amplifies by Wednesday as an upper trof
digs over the Plains, and that should bring our temps up closer to
ten degrees above normal Wednesday afternoon. Still think that we
will remain dry through the end of the day as the next cold front
remains well to our west and moisture return does not begin until
after sunset Wednesday.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
As of 230 PM Saturday: At the start of the extended high pressure
will continue to extend across the Carolinas and northeastern
Georgia as a digging trough in the Desert Southwest tracks east into
the Southern Plains. This high pressure system looks like it could
potentially lead to most of Thursday being dry as a cold front
slowly approaches from the west. Global models seem to be in good
agreement in regards to trending mostly dry Thursday with PoPs
trending upward late Thursday into Friday. The exception to this
would be the Canadian which pushes precip in earlier compared to the
GFS and ECMWF. Past Thursday models diverge in how they handle the
FROPA. The GFS seems to be the most bullish with the amount of
moisture associated with the cold front compared to the ECMWF and
Canadian. Currently the ECMWF seems to be the driest solution. The
GFS also tracks much slower across the CWA compared to the Canadian
and ECMWF, meaning PoPs would continue through potentially Saturday
afternoon/evening. Meanwhile the ECMWF and Canadian have high
pressure building into the region post FROPA Friday
afternoon/evening. This would mean drier conditions for the weekend.
Since models are still not in good agreement, regarding the timing
of the FROPA, I have opted to keep at least a chance for showers
Thursday into Saturday. In regards to instability associated with
this cold front late next week, both the ECMWF and GFS show some
CAPE present Friday afternoon and evening. Due to this I have
maintained a chance for thunderstorms across the southeastern CWA
for that time period. We will continue to monitor how this pattern
evolves in the coming days.

&&

.AVIATION /22Z SATURDAY THROUGH THURSDAY/...
At KCLT and Elsewhere: Anticipate one more round of rain showers
affecting the Upstate TAF sites and KCLT through the evening with
the approach of a surface wave along the wedge front draped in the
terminal area. Coverage may be more scattered KAVL to KHKY. Thunder
will be possible from mainly KAND to KCLT this evening, but these
locations could stay just on the stable side of the boundary so will
feature just showers for now. Winds remain difficult to pin down,
with mostly ESE to NE flow ahead of the wave, expected to toggle
quickly to NW tonight with the passing surface low. Expect NW winds
to pick up through the later part of the TAF period with some dry
and cold advection. The abundant low-level moisture should yield
LIFR cigs at most sites overnight, with IFR vsby, into Sunday
morning. Scattering and lifting to VFR will then occur through the
later morning hours with downslope flow, mixing, and improving
insolation. Low end gusts are likely on Sunday with the cold
advection and mixing.

Outlook: Dry high pressure returns on Sunday and lingers through he
middle of next week. The next chance for rain and associated
restrictions looks to be Thursday night at the earliest.

Confidence Table...

            21-03z        03-09Z        09-15Z        15-18Z
KCLT       High  88%     High  90%     Med   66%     High 100%
KGSP       High  88%     Med   68%     Med   60%     High 100%
KAVL       High  96%     Med   70%     High  81%     High  87%
KHKY       High  96%     Med   68%     Low   56%     Med   70%
KGMU       High  85%     Med   76%     Low   45%     Med   70%
KAND       Med   73%     High  93%     Med   75%     High 100%

The percentage reflects the number of guidance members agreeing
with the scheduled TAF issuance flight rule category. Complete hourly
experimental aviation forecast consistency tables are available at
the following link:

www.weather.gov/gsp/aviation

&&

.GSP WATCHES/WARNINGS/ADVISORIES...
GA...None.
NC...None.
SC...None.

&&

SYNOPSIS...AP
NEAR TERM...ARK/HG
SHORT TERM...PM
LONG TERM...AP
AVIATION...HG

Hazardous Weather Outlook
National Weather Service Greenville-Spartanburg SC
412 PM EDT Sat Apr 24 2021

GAZ026-028-029-NCZ071-072-082-SCZ006>014-019-252015-
Franklin-Hart-Elbert-Mecklenburg-Cabarrus-Union NC-
Greater Greenville-Spartanburg-Cherokee-York-Anderson-Abbeville-
Laurens-Union SC-Chester-Greenwood-
412 PM EDT Sat Apr 24 2021

This Hazardous Weather Outlook is for northeast Georgia, piedmont
North Carolina and upstate South Carolina.

.DAY ONE...Tonight.

A few thunderstorms are possible this evening around and south of the
I-85 corridor. Cloud to ground lightning and locally heavy rain will
be possible with any of these storms. A few storms may produce gusty
winds and hail approaching 1 inch in diameter.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed. Please relay any information about
observed severe weather to the NWS while following all local, state,
and CDC guidelines.

GAZ010-017-018-NCZ035>037-051>053-056>059-062>065-068>070-501>510-
SCZ001>005-252015-
Rabun-Habersham-Stephens-Alexander-Iredell-Davie-Swain-Haywood-
Buncombe-Catawba-Rowan-Graham-Northern Jackson-Macon-
Southern Jackson-Transylvania-Henderson-Cleveland-Lincoln-Gaston-
Caldwell Mountains-Greater Caldwell-Burke Mountains-Greater Burke-
McDowell Mountains-Eastern McDowell-Rutherford Mountains-
Greater Rutherford-Polk Mountains-Eastern Polk-Oconee Mountains-
Pickens Mountains-Greenville Mountains-Greater Oconee-
Greater Pickens-
412 PM EDT Sat Apr 24 2021

This Hazardous Weather Outlook is for northeast Georgia, piedmont
North Carolina, western North Carolina and upstate South Carolina.

.DAY ONE...Tonight.

A few thunderstorms are possible this evening. Cloud-to- ground
lightning and locally heavy rain will be possible with any of these
storms.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

None.

NCZ033-048>050-252015-
Avery-Madison-Yancey-Mitchell-
412 PM EDT Sat Apr 24 2021

This Hazardous Weather Outlook is for western North Carolina.

.DAY ONE...Tonight.

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

None.

Krentz

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>