Severe Thunderstorm Warning 206, NWS Greenville-Spartanburg, SC

007 
WWUS52 KGSP 171721
SVSGSP

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
121 PM EDT WED AUG 17 2016

NCC021-087-089-175-171730-
/O.EXP.KGSP.SV.W.0206.000000T0000Z-160817T1730Z/
TRANSYLVANIA NC-BUNCOMBE NC-HAYWOOD NC-HENDERSON NC-
121 PM EDT WED AUG 17 2016

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN TRANSYLVANIA...
SOUTH CENTRAL BUNCOMBE...SOUTHEASTERN HAYWOOD AND NORTHWESTERN
HENDERSON COUNTIES WILL EXPIRE AT 130 PM EDT...
                
THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED BELOW SEVERE
LIMITS...AND NO LONGER POSES AN IMMEDIATE THREAT TO LIFE OR PROPERTY.
THEREFORE THE WARNING WILL BE ALLOWED TO EXPIRE.

LAT...LON 3522 8278 3539 8290 3561 8255 3538 8238
TIME...MOT...LOC 1718Z 239DEG 15KT 3535 8277 

$$

07

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
1131 AM EDT WED AUG 17 2016

.SYNOPSIS...
High pressure over the Western Atlantic will weaken or move eastward
while allowing a cold front to become stationary across our area
Thursday.  This front will slowly dissipate as it acts as a focus
for mainly afternoon showers and thunderstorms into the weekend. A
stronger cold front will move in from the northwest early next week,
possibly bringing cooler and drier air by the middle of the week.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 1100 AM EDT: Temperatures are on the verge of hitting
convective temps and a robust cumulus field should develop in short
order. Low level convergence and weak upslope flow should start
triggering over the high terrain first, but low level convergence
axes may develop additional isolated to scattered activity in the
lower piedmont. With limited capping despite the warm temps aloft,
additional scattered piedmont to numerous mountain coverage should
form by mid to late afternoon. Anticipate a few strong storms, with
perhaps one or two severe, as a sharp DCAPE gradient has formed near
I-77. Severe criteria for today include 55 dbz above about 26 kft.

Otherwise, model guidance shows a piece of the flattened mid/upper
ridge remaining across the southeast through at least the next 24
hours. That means all the mid/upper forcing will remain to our w and
n thru the period, along with the plume of deeper moisture. Temps
might top out a degree or two warmer today because of less cloud
coverage early. For tonight, some convection might hold on well into
the overnight hours, probably on the fringe of the NC mtns once
again. Otherwise, will taper precip down to a slight chance. Temps
will remain warm.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
As of 300 AM Wed: Expectations for Thu-Fri have not changed much
from the previous forecast cycle. A weak frontal boundary will
extend from low pressure near the Canadian Maritimes southwestward
into the southern Plains on Thursday morning. Thermal advection
invof the front over our area looks to be essentially nonexistent,
though it will provide a source of low-level convergence. In the
presence of abundant moisture and modestly unstable profiles,
it is logical to expect enhanced convective coverage, with
locally heavy rainfall rates likely (and profiles supportive of
training/backbuilding). One interesting development is that the 4km
NAM develops only isolated showers out of these ingredients. The
NAM has done a bit better of late in depicting convective coverage,
so seeing that I opted not to increase PoPs, keeping them in chance
range across the forecast area.

The front will lay out from west to east across GA/SC Friday as
the parent low moves even further away, eventually stalling. It's
hard to pick out exactly where, or if, there will be a band of
forcing. Models generally produce less activity overall on Friday,
compared to Thursday. However it remains prudent to maintain PoPs
in chance range. PWAT values are slightly higher, suggesting still
better rainfall rates, under the continued unidirectional flow
regime. Westerly low-level flow does imply upsloping will initiate
activity over the NC/TN border, but it is not distinct enough to
expect downsloping will have a negative effect over the Piedmont.

Max temps will be near normal, with mins a category or so above
normal due to overnight cloud cover and excessive moisture.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
As of 130 AM Wed: The forecast for the weekend is hard to pin down,
with the nearby stationary front basically washing out as a
seasonally strong trough enters the Mississippi Valley. A generally
westerly flow will develop Saturday and last thru the weekend.
Conditions will remain unsettled during this time, with above-average
chances for mainly diurnal and garden-variety convection both Sat and
Sun, with near-normal temps. Meanwhile the trough advances to the
East Coast, bringing another cold front across the Appalachians
Monday or Monday night, possibly accompanied by a line of t-storms,
if the timing proves favorable. There is a strong signal from
guidance that the cold front will usher in dry continental high
pressure, with max temps a few degrees below normal.

&&

.AVIATION /16Z WEDNESDAY THROUGH SUNDAY/...
At KCLT:  Expect cumulus to form quickly with heating late this
morning. The latest model guidance suggests that today might be less
active than previously thought as we once again lack mid/upper
forcing and the plume of deeper moisture remains strung out to our N
as the subtropical ridge holds on. However, low level convergence
east of the airfield and activity moving off the high terrain to the
west will give us some late day tstm chance. Will feature a TEMPO
for TSRA from 20Z to 00Z for this along with gusty winds in higher
DCAPE. Wind should remain SW to S. Left out fog/low stratus around
daybreak Thursday until we have a better idea about precip today.

Elsewhere:  As model guidance backs off on extent of convective
precip, confidence is not great enough to go beyond PROB30s for
thunderstorms in the late afternoon and evening, even at KAVL,
although as one goes farther N and W the chances increase.
Otherwise...similar to KCLT.

Outlook: Thunderstorms will gradually increase in coverage through
late week, with a diurnal enhancement, as better moisture and a weak
cold front settle in from the NW. The boundary may stall in the
vicinity over the weekend to keep higher than normal chances of
thunderstorms going. Morning fog/stratus will be possible each day
in the NC mountain valleys, and possibly in locations that receive
soaking rains the previous aftn/evening.

Confidence Table...

            15-21Z        21-03Z        03-09Z        09-12Z
KCLT       High 100%     High 100%     High 100%     High 100%
KGSP       High 100%     High 100%     High 100%     High  88%
KAVL       High 100%     High 100%     High  94%     High  83%
KHKY       High 100%     High 100%     High 100%     High 100%
KGMU       High 100%     High 100%     High 100%     High  94%
KAND       High 100%     High 100%     High 100%     High  89%

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...Wimberley
NEAR TERM...HG/PM
SHORT TERM...Wimberley
LONG TERM...Wimberley
AVIATION...HG/PM

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
700 AM EDT WED AUG 17 2016

GAZ010-017-018-026-028-029-NCZ035>037-056-057-064-065-068>072-082-
501>510-SCZ001>014-019-181100-
RABUN-HABERSHAM-STEPHENS-FRANKLIN-HART-ELBERT-ALEXANDER-IREDELL-
DAVIE-CATAWBA-ROWAN-TRANSYLVANIA-HENDERSON-CLEVELAND-LINCOLN-GASTON-
MECKLENBURG-CABARRUS-UNION-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-GREATER GREENVILLE-SPARTANBURG-
CHEROKEE-YORK-ANDERSON-ABBEVILLE-LAURENS-CHESTER-GREENWOOD-
700 AM EDT WED AUG 17 2016

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE FOOTHILLS AND PIEDMONT
OF NORTH CAROLINA...SOUTH CAROLINA...AND NORTHEAST GEORGIA.

.DAY ONE...TODAY AND TONIGHT.

SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP THIS
AFTERNOON. IN ADDITION TO CLOUD TO GROUND LIGHTNING...ANY
THUNDERSTORMS WILL BE ABLE TO PRODUCE LOCALLY HEAVY RAINFALL.
COVERAGE WILL DIMINISH AFTER SUNSET...BUT A FEW STORMS MAY LINGER
OVER THE AREA INTO TONIGHT.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY.

..THURSDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..FRIDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..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.

.SPOTTER INFORMATION STATEMENT...

NONE.

NCZ033-048>053-058-059-062-063-181100-
AVERY-MADISON-YANCEY-MITCHELL-SWAIN-HAYWOOD-BUNCOMBE-GRAHAM-
NORTHERN JACKSON-MACON-SOUTHERN JACKSON-
700 AM EDT WED AUG 17 2016

THIS HAZARDOUS WEATHER OUTLOOK IS FOR A PORTION OF WESTERN NORTH
CAROLINA NEAR THE TENNESSEE BORDER.

.DAY ONE...TODAY AND TONIGHT.

NUMEROUS SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP THIS
AFTERNOON. IN ADDITION TO CLOUD TO GROUND LIGHTNING...ANY
THUNDERSTORMS WILL BE ABLE TO PRODUCE LOCALLY HEAVY RAINFALL.
WHILE COVERAGE WILL DIMINISH TO SOME DEGREE BY SUNSET...SCATTERED
STORMS MAY LINGER OVER THE AREA INTO TONIGHT.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY.

..THURSDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..FRIDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..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.

.SPOTTER INFORMATION STATEMENT...

NONE.

WIMBERLEY

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1213 PM EDT WED AUG 17 2016

SCZ006-012-171645-
GREATER GREENVILLE SC-LAURENS SC-
1213 PM EDT WED AUG 17 2016

...A STRONG THUNDERSTORM WITH INTENSE LIGHTNING WILL IMPACT
NORTHWESTERN LAURENS AND SOUTHEASTERN GREENVILLE COUNTIES UNTIL 1245
PM EDT...

AT 1212 PM EDT...DOPPLER RADAR WAS TRACKING A STRONG THUNDERSTORM
WITH INTENSE LIGHTNING 12 MILES SOUTH OF GREENVILLE DOWNTOWN...OR 4
MILES SOUTH OF DONALDSON CENTER...MOVING NORTHEAST AT 15 MPH.

LOCATIONS TO BE IMPACTED INCLUDE... GREENVILLE DOWNTOWN...GREENVILLE
EASTSIDE...MAULDIN...SIMPSONVILLE...FIVE FORKS...FOUNTAIN
INN...DONALDSON CENTER...PIEDMONT...WEST GREENVILLE AND FORK SHOALS.

IN ADDITION TO INTENSE LIGHTNING...WIND GUSTS UP TO 40 MPH WILL BE
POSSIBLE IN THESE AREAS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

GUSTY WINDS CAN BLOW DOWN TREES THAT ARE DEAD...OR THAT HAVE WEAKENED
ROOT SYSTEMS. OUTDOOR FURNITURE AND SIMILAR ITEMS CAN BE TOSSED
AROUND IF NOT ANCHORED. SEEK SHELTER INDOORS.

FREQUENT LIGHTNING IS OCCURRING WITH THIS STORM. IF OUTDOORS...TRY TO
GET INDOORS OR INTO A HARD TOPPED VEHICLE. OTHERWISE...STAY AWAY FROM
OPEN AREAS AND ISOLATED HIGH OBJECTS SUCH AS TREES. WHEN INDOORS...
STAY AWAY FROM WINDOWS AND DOORS AND AVOID USING WIRED ELECTRONIC
DEVICES. DO NOT TAKE A SHOWER OR BATH. TRY TO UNPLUG UNNECESSARY
APPLIANCES BEFORE THE STORM APPROACHES.

&&

LAT...LON 3462 8245 3464 8245 3466 8246 3466 8247
      3467 8247 3468 8246 3470 8246 3471 8247
      3471 8246 3472 8247 3490 8238 3473 8208
      3454 8232
TIME...MOT...LOC 1612Z 211DEG 11KT 3468 8236

07

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1232 PM EDT WED AUG 17 2016

NCZ033-501-171700-
CALDWELL MOUNTAINS NC-AVERY NC-
1232 PM EDT WED AUG 17 2016

...A STRONG THUNDERSTORM WITH INTENSE LIGHTNING WILL IMPACT
NORTHWESTERN CALDWELL AND EAST CENTRAL AVERY COUNTIES UNTIL 100 PM
EDT...

AT 1232 PM EDT...DOPPLER RADAR WAS TRACKING A STRONG THUNDERSTORM
WITH INTENSE LIGHTNING 5 MILES SOUTH OF FOSCOE...OR NEAR GRANDFATHER
MOUNTAIN...MOVING NORTHEAST AT 15 MPH.

LOCATIONS TO BE IMPACTED INCLUDE... BLOWING ROCK IN CALDWELL
COUNTY...BANNER ELK...SUGAR MOUNTAIN...SEVEN DEVILS...GRANDFATHER
MOUNTAIN...GRANDFATHER MOUNTAIN STATE PARK...B.R.
PARKWAY-LINVILLE FALLS TO GRANDFATHER...UPTON...EDGEMONT AND LINVILLE.

IN ADDITION TO INTENSE LIGHTNING...WIND GUSTS UP TO 50 MPH WILL BE
POSSIBLE IN THESE AREAS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

GUSTY WINDS CAN BLOW DOWN TREES THAT ARE DEAD...OR THAT HAVE WEAKENED
ROOT SYSTEMS. OUTDOOR FURNITURE AND SIMILAR ITEMS CAN BE TOSSED
AROUND IF NOT ANCHORED. SEEK SHELTER INDOORS.

FREQUENT LIGHTNING IS OCCURRING WITH THIS STORM. IF OUTDOORS...TRY TO
GET INDOORS OR INTO A HARD TOPPED VEHICLE. OTHERWISE...STAY AWAY FROM
OPEN AREAS AND ISOLATED HIGH OBJECTS SUCH AS TREES. WHEN INDOORS...
STAY AWAY FROM WINDOWS AND DOORS AND AVOID USING WIRED ELECTRONIC
DEVICES. DO NOT TAKE A SHOWER OR BATH. TRY TO UNPLUG UNNECESSARY
APPLIANCES BEFORE THE STORM APPROACHES.

&&

LAT...LON 3616 8183 3611 8181 3612 8169 3612 8158
      3597 8173 3606 8193 3619 8186
TIME...MOT...LOC 1632Z 212DEG 15KT 3609 8179

07