Special Weather Statement, NWS Greenville-Spartanburg, SC

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
354 AM EDT Fri Mar 31 2017

.SYNOPSIS...
A cold front will sweep across the forecast area today, with dry and
warm high pressure building into the area through the weekend.
Unsettled weather returns early next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
Widespread showers and scattered thunderstorms will continue across
much of the CWA through at least sunrise, after which precip should
begin moving east of the area. Per the latest SPC Mesoanalysis, weak
surface-based buoyancy lingers across much of the area, while
shear/helicity parameters are more than adequate for
organized/rotating cells. Thus, the severe weather threat remains
non-zero, and we will continue to maintain a close eye on deeper
convective segments for possible brief spin-ups, as brief, weak
tornadoes will probably be the most likely severe weather threat
going forward. The hydro situation will also need some scrutiny, as
a swath of storm total rainfall of 1.5 to 2.5 inches has occurred
along the Blue Ridge escarpment in North Carolina. Flood-prone
streams in Transylvania and especially Henderson Counties are
nearing flood stage, and another burst of heavy rain could put them
over the top.

Otherwise, convective bands are expected to be completely clear of
the forecast area by late morning. However, the cold front will take
its time pushing through the area today, and perhaps the biggest
question regarding today's forecast is whether additional convection
will be able to fire along the boundary across the Piedmont and
foothills this afternoon, especially as the cold mid-level core
associated with the upper low passes by just north of the area.
Indeed, some of the more reliable hires mesoscale guidance does
initiate scattered convection this PM, with enough of a signal
to allow a small pop to linger across northern and eastern zones
into the afternoon. Max temps will be a sold 5 degrees above climo
today.

Much quieter and cooler tonight as drier air gradually filters into
the forecast area. Min temps are still expected to be about 5
degrees above normal.

&&

.SHORT TERM /SATURDAY THROUGH MONDAY/...
As of 200 AM EDT Friday:  The short term fcst period kicks off on
Saturday morning in the wake of a departing upper trof leading
into building heights aloft thanks to an approaching ridge
axis, while another closed H5 cyclone gains strength across the
Desert Southwest.  At the surface, nwly flow will prevail at fcst
initialization given the intrusion of a broad anticyclone that
will dive through the Great Lakes region into the OH Valley,
with enough remnant llv moisture to provide low end chances
for upslope showers across the northern NC high terrain for a
few hours.  Pattern evolution through Saturday and Sunday will
be highlighted by migration of the aforementioned surface ridge
to the east allowing flow to gradually veer nely Saturday night
into Sunday morning.  Meanwhile to the west, cyclogenesis will
initiate beneath the ejecting upper cyclone over TX leading to
modest GOM moisture advection into the Lower MS River Valley.
By daybreak Sunday, guidance favors upper ridging centered atop
the east coast, while the above mentioned surface ridge wedges in
the lee of the Appalachians.  All in all leading to a fairly nice
Sunday for northeast GA and the western Carolinas highlighted by
partly cloudy skies and above normal temperatures.

More importantly, the focus of the fcst will shift to the
progression of the synoptic pattern Sunday night into Monday
morning as the upper low slides into the MS Valley, and the
warm/moist sector expands eastward across much of the deep south.
At the same time, the elongated surface ridge over the east coast
looks to remain entrenched providing backed ely yet veering sely
surface flow.  Guidance favors widespread convection Sunday night
across Dixie Alley in association with large scale upper ascent
and deep shear, all making a run across AL and into western GA by
periods end Monday morning.  Meanwhile closer to home, increasing
moist southerly flow looks orthogonal to the escarpment therefore
chances for upslope showers will be on the rise.

&&

.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
As of 230 AM EDT Friday:  The medium range fcst period kicks off
on Monday morning amidst an amplified upper pattern east of the
Rockies highlighted by a deep/closed H5 cyclone rolling through
the lower/mid MS River Valley, while a sharp ridge axis dominates
along the eastern shores.  At the surface, an elongated region of
high pressure will prevail beneath the aforementioned upper ridge,
while a deep surface cyclone moves through Dixie Alley all the
while promoting widespread convection.  Pattern evolution through
Monday could be quite interesting as the guidance favors modest
upper divergence across the southeast states ahead of the upper low
moving into the OH Valley.  With that, flow through the profile
is quite veered, especially east of the I75 corridor where the
Atlantic ridge influences look to yield backed sely flow beneath
sharp veering aloft.  Thus low/mid level srh will be maximized in
these regions on Monday afternoon, which is were model CAPE progs
are maxed as well, however generally in the 4-6 hundred j/kg range.
Therefore am expecting convection to move east out of TN/GA into
the Carolinas through the day Monday with strong/severe convection
certainly possible, especially across northeast GA and the extreme
western Carolinas.

The initial system looks to clear the region to the east by sunrise
Tuesday allowing for heights to rise somewhat, albeit amidst fairly
zonal H5 flow.  The surface field will modify slightly behind this
first system, however any pronounced cold frontal features aren't
present therefore wouldn't be surprised if any nwly post system flow
is brief, with sly flow to return rather quickly.  Flat ridging
looks to highlight the pattern through Tuesday while a shortwave
dives out of western Canada into the northern Rockies/Plains,
and thus aids longwave trof development.  Surface cyclogenesis
is favored beneath said troffing by daybreak Wednesday over the
Midsouth, quickly advecting northeast into the OH valley by late
morning driving a cold front across the MS River.  At this point,
the operational guidance tends to diverge with respect to timing of
the frontal intrusion/passage across the TN valley into northeast GA
and the western Carolinas.  The ECMWF is much more progressive thus
pushing the front quickly through the region late Wednesday all the
while holding broad cyclonic flow aloft as another shortwave dives
sharply southward from Canada into the southern Appalachians to
round out the period.  The GFS on the other hand is much slower as
the front looks to stall to the west through early Thursday morning
before the secondary shortwave comes into play and therefore surges
the front through the region during the daytime hours of Thursday.
Either way it looks as if another round of widespread convection is
possible, with timing yet to be determined.  Overall, temperatures
through the medium range will be above normal levels.

&&

.AVIATION /08Z FRIDAY THROUGH TUESDAY/...
At KCLT and elsewhere: Surface wedge has eroded at all terminals
except KHKY, resulting in cigs lifting to MVFR or even VFR
everywhere except KHKY. Meanwhile, showers and thunderstorms will
continue to move northeast across the forecast area this morning,
likely pushing east of the area from sunrise through late morning.
While guidance indicates cigs should settle back at IFR at some
point, this seems to be a bit dubious, and IFR is expected to be
more a result of showers or storms passing over the terminals.
Therefore, made rather liberal use of tempos for IFR conditions,
while prevailing primarily MVFR cigs (VFR visby should prevail
outside of showers). Otherwise, gusty S/SE winds will be possible
through the morning, becoming SW by late morning, with gusts
remaining possible into the afternoon. These SW winds will usher in
drier air, which will lift and scatter cigs and bring an end to
convective chances.

Outlook: Drier conditions will return behind the front for the
weekend, but with unsettled weather and associated restrictions
again developing early next week.

Confidence Table...

            08-14Z        14-20Z        20-02Z        02-06Z
KCLT       High  90%     High  90%     High 100%     High 100%
KGSP       High  80%     High  92%     High 100%     High 100%
KAVL       Med   71%     High  90%     High 100%     High  95%
KHKY       Med   76%     High  84%     High 100%     High 100%
KGMU       Med   76%     High  93%     High 100%     High 100%
KAND       Low   58%     High  95%     High 100%     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 and ensemble forecasts
are available at the following link:

www.weather.gov/gsp/aviation

&&

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

&&

SYNOPSIS...JDL
NEAR TERM...JDL
SHORT TERM...CDG
LONG TERM...CDG
AVIATION...JDL

Hazardous Weather Outlook
National Weather Service Greenville-Spartanburg SC
422 AM EDT Fri Mar 31 2017

NCZ033-049-050-053-063>065-501-503-505-507-509-SCZ001>003-010830-
Avery-Yancey-Mitchell-Buncombe-Southern Jackson-Transylvania-
Henderson-Caldwell Mountains-Burke Mountains-McDowell Mountains-
Rutherford Mountains-Polk Mountains-Oconee Mountains-
Pickens Mountains-Greenville Mountains-
422 AM EDT Fri Mar 31 2017

This Hazardous Weather Outlook is for western North Carolina and
upstate South Carolina.

.DAY ONE...Today and Tonight.

Widespread rain showers and a few thunderstorms will continue across
the North Carolina Blue Ridge this morning. These areas have seen
rainfall amounts of 1.5 to 2.5 inches since Thursday, and additional
amounts of up to an inch remain possible. This could be enough to
cause isolated flash flooding, especially across the counties
bordering South Carolina. In addition, thunderstorms could produce
occasional cloud to ground lightning.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

..Saturday...No hazardous weather is expected at this time.
..Sunday...No hazardous weather is expected at this time.
..Monday...No hazardous weather is expected at this time.
..Tuesday...No hazardous weather is expected at this time.
..Wednesday...No hazardous weather is expected at this time.
..Thursday...No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

None.

GAZ018-026-028-029-NCZ035>037-056-057-068>072-082-502-504-506-508-
510-SCZ004>014-019-010830-
Stephens-Franklin-Hart-Elbert-Alexander-Iredell-Davie-Catawba-Rowan-
Cleveland-Lincoln-Gaston-Mecklenburg-Cabarrus-Union-Greater Caldwell-
Greater Burke-Eastern McDowell-Greater Rutherford-Eastern Polk-
Greater Oconee-Greater Pickens-Greater Greenville-Spartanburg-
Cherokee-York-Anderson-Abbeville-Laurens-Chester-Greenwood-
422 AM EDT Fri Mar 31 2017

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

.DAY ONE...Today and Tonight.

Scattered thunderstorms and numerous heavy rain showers will continue
across the foothills and Piedmont of the Carolinas and northeast
Georgia this morning. While the main threats will be from occasional
cloud to ground lightning and locally heavy rainfall, an isolated
severe storm cannot be ruled out. The main severe weather threats
would be from brief damaging winds, and perhaps a brief, weak
tornado.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

..Saturday...No hazardous weather is expected at this time.
..Sunday...No hazardous weather is expected at this time.
..Monday...No hazardous weather is expected at this time.
..Tuesday...No hazardous weather is expected at this time.
..Wednesday...No hazardous weather is expected at this time.
..Thursday...No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

None.

GAZ010-017-NCZ048-051-052-058-059-062-010830-
Rabun-Habersham-Madison-Swain-Haywood-Graham-Northern Jackson-Macon-
422 AM EDT Fri Mar 31 2017

This Hazardous Weather Outlook is for northeast Georgia and western
North Carolina.

.DAY ONE...Today and Tonight.

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

..Saturday...No hazardous weather is expected at this time.
..Sunday...No hazardous weather is expected at this time.
..Monday...No hazardous weather is expected at this time.
..Tuesday...No hazardous weather is expected at this time.
..Wednesday...No hazardous weather is expected at this time.
..Thursday...No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

None.

Lane

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
147 AM EDT FRI MAR 31 2017

NCZ064-065-310615-
Transylvania NC-Henderson NC-
147 AM EDT FRI MAR 31 2017

...A STRONG THUNDERSTORM WILL IMPACT CENTRAL TRANSYLVANIA AND WEST
CENTRAL HENDERSON COUNTIES UNTIL 215 AM EDT...

At 147 AM EDT, Doppler radar was tracking a strong thunderstorm 7
miles west of Brevard, or 4 miles northwest of Rosman, moving
northeast at 30 mph.

Locations to be impacted include...
Brevard, Rosman, Graveyard Fields, Mount Pisgah, Looking Glass,
Etowah, Little River In Transylvania County, Balsam Grove, Penrose
and Connestee.

Wind gusts up to 40 mph will be possible in these areas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This storm may intensify, so be certain to monitor local radio and tv
stations, as well as local cable tv outlets for additional
information and possible warnings from the National Weather Service.

&&

LAT...LON 3526 8255 3513 8284 3522 8294 3532 8286
      3532 8283 3537 8279 3538 8279 3539 8277
      3541 8275 3542 8275 3542 8274
TIME...MOT...LOC 0547Z 229DEG 27KT 3520 8285

KRENTZ

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
406 AM EDT FRI MAR 31 2017

GAZ028-SCZ001>006-010-310845-
Hart GA-Greater Pickens SC-Pickens Mountains SC-Greater Oconee SC-
Anderson SC-Oconee Mountains SC-Greenville Mountains SC-
Greater Greenville SC-
406 AM EDT FRI MAR 31 2017

...STRONG THUNDERSTORMS WILL IMPACT HART...NORTHWESTERN GREENVILLE...
CENTRAL ANDERSON...PICKENS AND SOUTHEASTERN OCONEE COUNTIES UNTIL 445
AM EDT...

At 405 AM EDT, Doppler radar indicated strong thunderstorms along a
line extending from 11 miles northwest of Pickens to 11 miles
southeast of Carnesville, and moving northeast at 35 mph.

Locations to be impacted include...
Anderson, Easley, Clemson, Seneca, Hartwell, Pickens, Homeland Park,
Central, Northlake and Pendleton.

Wind gusts up to 45 mph will be possible in these areas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

These storms may intensify, so be certain to monitor local radio and
tv stations, as well as local cable tv outlets for additional
information and possible warnings from the National Weather Service.

&&

LAT...LON 3426 8311 3435 8310 3502 8288 3518 8246
      3516 8246 3517 8244 3519 8242 3520 8240
      3441 8262 3423 8300 3423 8308
TIME...MOT...LOC 0805Z 234DEG 32KT 3500 8284 3425 8309

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>

<!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>