Special Weather Statement, NWS Greenville-Spartanburg, SC

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
430 PM EDT Fri Jul 9 2021

.SYNOPSIS...
A weak cold front will lay over to the north of the region tonight
through Saturday. Warm and moist high pressure will set up over the
southeast through the rest of the weekend and persist throughout
next week.

&&

.NEAR TERM /THROUGH SATURDAY/...
As of 430 PM Friday: Cluster of pre-frontal tstms have really turned
over the air mass across the forecast area, as vis sat imagery shows
little cu in the storms' wake. A cold front was still analysed
just northwest of the TN/NC border, and that will likely trigger
a few more showers and storms across the NC mountains as it pushes
thru. But activity elsewhere should be fairly isolated due to much
less CAPE. Updated the PoPs with the latest hourly NBM grids and
that lines up with the radar/sat trends. Temps were also tweaked
as they have come down to the 70s to lower 80s for most of the area.

Otherwise, thru the near-term period the upper pattern is expected
to flatten and deamplify across the region. A weak cold front over
the lower OH Valley region should approach our area with enough
mid/upper lvl support to keep it moving thru tonight. For tomorrow,
model guidance once again suggests a favorable environment for
thunderstorms to develop over the western Carolinas and northeast
Georgia. Although the mid/upper lvl forcing appears minimal,
the air mass should be able to sustain mixed-layer CAPE of approx
1000-2000 J/kg by midday but minimal shear (<15 kt). A few storms
will likely become strong to severe, although most of the stronger
storms will likely remain to our west. Coverage should decrease
by the early evening, with lingering showers possible well into
the night. Temps will remain slightly above normal.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
As of 130 pm EDT Friday: A deep, closed, low pressure system will
cut off from the Midwest to the southern Plains Saturday night
through Sunday. With this sytem in place to the west, and
strengthening Bermuda high pressure in place off the southeast
coast, southerly flow will continue over our region along with
elevated moisture levels. The stacked low pressure system will
slowly start to fill through Monday. The persistent, deep southerly
flow will maintain precipitable water values of 1.5 to 2 inches in
area profiles, with daily thunderstorm chances running well above
climo each afternoon and evening. Will keep the coverage best across
the NC mountains where light terrain triggering in the southerly
upslope will be best. Surface based instability and lapse rates look
fairly unimpressive and this should mute the severe thunderstorm
threat each day. Expect near climo temps on Sunday, maybe a few
degrees below on maxes with clouds on Monday.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
As of 140 pm EDT Friday: An upper level trough axis west of the
Appalachians early in the period on Tuesday will slowly deamplify as
it moves east through the week. With a moist and unstable airmass
persisting across the region, precipitation will maintain a focus of
mainly diurnal convection each afternoon and evening, with more
isolated shower coverage at night. PoPs will be best over the
mountains where the moisture will be deeper and forcing better.
Slightly more zonal flow will develop briefly on Thursday as the
northern tier wave phases back into the westerlies, but with
cyclonic flow redeveloping upstream by Friday. Little to no airmass
change during this period means persistence on near climo temps and
above climo diurnal rainfall chances through Friday.

&&

.AVIATION /21Z FRIDAY THROUGH WEDNESDAY/...
At KCLT and elsewhere: A weak cold front will continue to push
thru the fcst area this aftn and early evening generating sct to
numerous showers and thunderstorms as it does. The latest CAM
guidance has the bulk of the activity south and/or east of our
fcst area by 23z or so, with the possibility of a few lingering
showers. As such, I kept a TEMPO for TSRA at all sites (except
KHKY and KAVL) for the first 4 hrs or so of the taf period. It's
looking like the thunderstorms have already moved east of KHKY
and KAVL, and they will only see showers for the rest of the
afternoon/evening. After the convection moves east, winds should
continue to favor a WSWLY direction and eventually become light
and vrb overnight. They will eventually pick back up from the S
towards the end of the taf period late tomorrow morning/early aftn.
The only exception will be KAVL, where winds will favor a NWLY
direction thru tonight and into the overnight before becoming
light and vrb tomorrow morning. In addition, we'll likely see
some fog developing over the mtn valleys and possibly the NC
Piedmont early Saturday morning.

Outlook: An unsettled pattern, with mainly diurnal convection
and morning stratus/fog, is expected to persist thru the weekend
and into early next week.

Confidence Table...

            20-02Z        02-08Z        08-14Z        14-18Z
KCLT       High 100%     High 100%     High 100%     High 100%
KGSP       High 100%     High 100%     High 100%     High 100%
KAVL       High 100%     High 100%     High  87%     High 100%
KHKY       High 100%     High 100%     High 100%     High 100%
KGMU       High 100%     High 100%     High 100%     High 100%
KAND       High 100%     High 100%     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 are available at
the following link:

www.weather.gov/gsp/aviation

&&

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

&&

SYNOPSIS...HG
NEAR TERM...ARK/JPT
SHORT TERM...HG
LONG TERM...HG
AVIATION...JPT

Hazardous Weather Outlook
National Weather Service Greenville-Spartanburg SC
218 PM EDT Fri Jul 9 2021

GAZ010-017-NCZ033-048>053-058-059-062>065-501>510-SCZ001>003-101830-
Rabun-Habersham-Avery-Madison-Yancey-Mitchell-Swain-Haywood-Buncombe-
Graham-Northern Jackson-Macon-Southern Jackson-Transylvania-
Henderson-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-
218 PM EDT Fri Jul 9 2021

This Hazardous Weather Outlook is for the mountains of northeast
Georgia, the mountains and foothills of western North Carolina, and
the mountains of Upstate South Carolina.

.DAY ONE...This afternoon and tonight.

Isolated to scattered thunderstorms may redevelop across the
mountains and foothills late this afternoon and this evening. Cloud
to ground lightning strikes and locally heavy rainfall will be the
main threats with any thunderstorms that redevelop.

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

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

None.

GAZ018-026-028-029-NCZ035>037-056-057-068>072-082-SCZ004>014-019-
101830-
Stephens-Franklin-Hart-Elbert-Alexander-Iredell-Davie-Catawba-Rowan-
Cleveland-Lincoln-Gaston-Mecklenburg-Cabarrus-Union NC-
Greater Oconee-Greater Pickens-Greater Greenville-Spartanburg-
Cherokee-York-Anderson-Abbeville-Laurens-Union SC-Chester-Greenwood-
218 PM EDT Fri Jul 9 2021

This Hazardous Weather Outlook is for northeast Georgia, the Piedmont
of western North Carolina, and Upstate South Carolina.

.DAY ONE...This afternoon and tonight.

Thunderstorms will roll east through the region this afternoon before
diminishing from the west early this evening. A few of the
thunderstorms will be strong to severe, with damaging wind gusts and
large hail possible. Frequent lightning and heavy downpours will
also accompany the thunderstorms.

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

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

None.

HG

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
313 PM EDT FRI JUL 09 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0215 PM     TSTM WND DMG     3 NW LOWESVILLE         35.45N 81.03W
07/09/2021                   LINCOLN            NC   AMATEUR RADIO

            TREES AND POWERLINES DOWN ON HOUSE ON BROADLEAF DR.

&&

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
339 PM EDT Fri Jul 9 2021

NCZ082-092015-
Union NC-
339 PM EDT Fri Jul 9 2021

...A CLUSTER OF THUNDERSTORMS WILL IMPACT SOUTHERN UNION COUNTY UNTIL
415 PM EDT...

At 339 PM EDT, Doppler radar indicated the leading edge of a cluster
of thunderstorms along a line extending from 3 miles west of Monroe
to 6 miles northeast of Lancaster, and moving southeast at 30 mph.

Locations to be impacted include...
Monroe, Wesley Chapel, Waxhaw, Mineral Springs, Weddington, Jaars and
Trinity.

Wind gusts up to 45 mph and pea size hail will be possible in these
areas.

LAT...LON 3487 8031 3481 8032 3482 8079 3489 8079
      3504 8073 3488 8031
TIME...MOT...LOC 1939Z 312DEG 25KT 3497 8060 3480 8073

LANE

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
405 PM EDT FRI JUL 09 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0205 PM     TSTM WND DMG     3 NW LOWESVILLE         35.46N 81.04W
07/09/2021                   LINCOLN            NC   TRAINED SPOTTER

            TRAINED SPOTTER REPORTED TREE FELL DOWN ONTO A HOUSE.

&&

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
501 PM EDT Fri Jul 9 2021

NCZ502-092130-
Greater Caldwell NC-
501 PM EDT Fri Jul 9 2021

...A STRONG THUNDERSTORM WILL IMPACT SOUTHEASTERN CALDWELL COUNTY
UNTIL 530 PM EDT...

At 501 PM EDT, Doppler radar was tracking a strong thunderstorm near
Lenoir, moving southeast at 20 mph.

Locations to be impacted include...
Lenoir, Sawmills, Granite Falls, Hudson, Cajah's Mountain, Gamewell,
Lake Rhodhiss and Northlakes.

Wind gusts up to 45 mph and half inch hail will be possible in these
areas.

LAT...LON 3580 8136 3579 8135 3578 8144 3579 8145
      3578 8150 3590 8161 3594 8153
TIME...MOT...LOC 2101Z 324DEG 16KT 3588 8153

LANE

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
509 PM EDT FRI JUL 09 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0159 PM     TSTM WND DMG     3 NW COOLEEMEE          35.85N 80.59W
07/09/2021                   DAVIE              NC   911 CALL CENTER

            911 CALL CENTER REPORTED TREES DOWN ON JUNCTION RD.

&&

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
643 PM EDT Fri Jul 9 2021

NCZ037-092315-
Davie NC-
643 PM EDT Fri Jul 9 2021

...A STRONG THUNDERSTORM WILL IMPACT NORTHEASTERN DAVIE COUNTY UNTIL
715 PM EDT...

At 643 PM EDT, Doppler radar was tracking a strong thunderstorm 9
miles southeast of Yadkinville, or near Huntsville, moving southeast
at 10 mph.

Locations to be impacted include...
Bermuda Run and Farmington.

Wind gusts up to 45 mph and pea size hail will be possible in these
areas.

LAT...LON 3591 8050 3605 8061 3605 8050 3604 8049
      3605 8047 3606 8047 3606 8046 3603 8044
      3600 8041 3599 8042 3598 8041
TIME...MOT...LOC 2243Z 309DEG 9KT 3604 8053

LANE