Severe Thunderstorm Warning 39, NWS Greenville-Spartanburg, SC

564 
WWUS52 KGSP 162046
SVSGSP

Severe Weather Statement
National Weather Service Greenville-Spartanburg SC
446 PM EDT WED MAY 16 2018

NCC159-162055-
/O.CAN.KGSP.SV.W.0039.000000T0000Z-180516T2100Z/
Rowan NC-
446 PM EDT WED MAY 16 2018

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN ROWAN COUNTY IS
CANCELLED...
        
The storm which prompted the warning has weakened below severe
limits, and has exited the warned area. Therefore the warning has 
been cancelled.  However heavy rain is still possible with 
additional thunderstorms that will cross the extreme southeast 
corner of the county.

LAT...LON 3550 8040 3551 8040 3567 8032 3563 8029
      3563 8027 3561 8024 3559 8023 3559 8021
      3555 8021 3554 8020 3553 8020 3551 8018
TIME...MOT...LOC 2044Z 219DEG 12KT 3561 8021 

$$

MOORE

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
306 PM EDT Wed May 16 2018

.SYNOPSIS...
The threat for numerous showers and a few thunderstorms will
linger for the rest of the week as a slow moving low pressure system
impacts our region. Locally heavy rainfall remains possible each
day. High temperatures will be near normal and low temperatures
about ten degrees above normal.

&&

.NEAR TERM /THROUGH THURSDAY/...
As of 200 PM EDT: Precip has morphed into much more of a convective
mode this afternoon, with numerous showers and a few thunderstorms
spreading across the entire CWFA. Moist, southerly upslope flow off
a Bermuda-style surface high combined with instability analyzed near
1500-2000 J/kg will continue to allow plentiful convection through
the afternoon and evening hours in Upstate SC and the NC Piedmont,
with some embedded thunderstorms likely. A few stronger storms with
gusty winds and small hail can't be ruled out, though severe weather
is not particularly likely this afternoon considering the very wet
profiles. Shower activity will continue through the afternoon in the
NC mountains, though instability there is much lower due to the
rainfall that has persisted much of the day.

Flooding is still the main concern across the area, with some
locations along the Blue Ridge Escarpment (especially the French
Broad Valley) having received 4-6 inches, with locally higher
amounts. Most other areas have received 1-2 inches since yesterday,
though the convection this afternoon could potentially double those
totals in the areas that see the most tropical thunderstorms.
Potential for a hydro watch is increasing considering the antecedent
conditions that have set up based on rainfall received so far today,
and the decision if/where a watch may be issued will depend on the
rainfall totals with the convection that occurs this evening.

As diurnal heating wanes this evening, thunderstorm activity will
begin to die down, though shower activity will continue through
midnight across much of Upstate SC and potentially the NC mountains.
A brief lull in showers is likely across the area some time between
midnight and daybreak, though CAMs have been struggling somewhat
with coverage and exactly when the lull will occur. An important
note is that instability, and therefore shower coverage, was
significantly underestimated by the hi-res models this morning, and
there is little reason that something similar won't happen again
tomorrow morning. Confidence in precip coverage in the early morning
hours is therefore low, as is confidence in the exact location of
additional higher QPF values.

The surface low over the Gulf that has aided deep tropical moisture
transport to the area over the past few days will finally move
slowly northward tomorrow, likely somewhere over our forecast area.
The upper low/open wave will also shift slightly northeastward,
placing very good upper forcing over our forecast area tomorrow
afternoon. With plentiful deep tropical moisture in place tomorrow,
a shield of heavy rainfall with embedded thunderstorms will likely
materialize over much of the CWFA after noon, though the location of
the axis of highest QPF totals remains uncertain due to uncertainty
in the track of the surface low. High temperatures will remain near
to just below average, with low temperatures about 10 degrees above
average due to the high moisture content.

&&

.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY NIGHT/...
As of 232 pm Wednesday: A bit of a change seen in the model guidance
as to the upper pattern once we get into the weekend. Before
then...no real changes in the synoptic situation with an upper trof
axis to the west that maintains a flow of sub-tropical moisture
across the western Carolinas and northeast Georgia Thursday
night through Saturday. Thinking has not changed with regard to
this forecast...in that we will need to keep a likely/categorical
precip prob during high points in the diurnal cycle with at least
a chance during the low points. With no air mass change, a shower
could develop at any time at any location. Thunderstorms will
be most likely in the afternoon and evening, and some of them
could be severe mainly east of the mtns given adequate CAPE on
the order of 1500 J/kg during peak heating, but overall our main
concern will be flooding. The PW will remain up around the top end
of the climatology, so some of the ingredients will be in place,
while fcst soundings show a deep warm cloud layer and potential
for training storms. However, the uncertainty as to where and
when prevents the issuance of a Flood Watch. Temps will remain
in the similar range for highs and lows as compared to the past
day or two. Which brings us to the end of the week. The guidance
has trended toward lifting the upper trof axis northeastward
on Friday, enhancing our potential precip coverage thru Friday
night, and then drawing a deamplifying trof axis across the fcst
area on Saturday. If this happens, Saturday would be another busy
day with numerous showers and storms, very similar to every other
day recently. The main effect will be that once the axis passes we
might actually dry out late Saturday night/early Sunday morning. The
fcst will reflect this optimistic thinking.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
As of 200 pm Wednesday: With little airmass change, the wet pattern
will likely continue in some fashion through the long-term period.
Early on, expect heights to rise over the southeast on Sunday, with
mid-levels drying out very slightly under the ridge. Warming
temperatures under the ridge could also have a slightly suppressive
effect on afternoon/evening convection and low-level flow should
also generally lose the upslope component of previous days. However,
precipitable water values remain high and scattered to numerous
mountain convection is still expected, with scattered storms in the
higher sbCAPE piedmont regions as well on Sunday afternoon/evening.

Meanwhile, the GFS features a weak inverted trough crossing FL under
the ridge on Sunday which might bring additional rounds of moisture
back toward the base of the southern Appalachians during the early
to middle part of next week. Uncertainty is quite high on this as
the feature is a bit more muted on the ECM/CMC compared to the GFS,
but most models have some semblance of weak trough and associated
voricity sliding up toward the region. Also, a surface frontal
boundary will lay out to the north of the region Monday through
Wednesday. This should allow high precipitable water values to stay
pooled across the region. High PoPs are thus expected given the
moist airmass despite the lack of organized forcing. The westerlies
will begin to pick up over the region by mid week, but little change
of airmass is expected and hydrologic threats will continue.

&&

.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
At KCLT and elsewhere: Convection is ongoing at/near all sites this
afternoon, and will continue to do so through the rest of this
evening. thunder is possible at all sites  A lull in convection
appears likely between midnight and daybreak, though confidence in
that lull is low considering that similar conditions this morning
were poorly handled by the forecast models. The moist pattern
remains tonight, so deterioration of cigs and vis to IFR conditions
(or perhaps lower in the early morning hours) is likely, though how
long restrictions will last as well as placement of any remaining
showers makes for a tricky forecast for restrictions yet again
tomorrow morning. Another area of showers and thunderstorms will
spread across the area tomorrow afternoon, bringing the potential
for SHRA, TS, and associated restrictions to most sites again
tomorrow afternoon.

Outlook: Deep moisture will persist through the rest of the week.
Showers, thunderstorms, and restrictions will continue into late
week. With the overall pattern changing little, unsettled weather is
expected to persist into early next week.

Confidence Table...

            19-01Z        01-07Z        07-13Z        13-18Z
KCLT       High  98%     High  94%     High  80%     High  82%
KGSP       High  92%     High  82%     High  87%     Med   72%
KAVL       Med   70%     High  91%     High  84%     High  84%
KHKY       High  89%     High  81%     High  83%     High  87%
KGMU       High  93%     High  92%     High  87%     High  90%
KAND       High  93%     High  91%     Med   77%     High  82%

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...JMP
NEAR TERM...Carroll
SHORT TERM...PM
LONG TERM...HG
AVIATION...Carroll

Hazardous Weather Outlook
National Weather Service Greenville-Spartanburg SC
530 AM EDT Wed May 16 2018

GAZ010-017-018-026-028-029-NCZ033-035>037-048>053-056>059-062>065-
068>072-082-501>510-SCZ001>014-019-170930-
Rabun-Habersham-Stephens-Franklin-Hart-Elbert-Avery-Alexander-
Iredell-Davie-Madison-Yancey-Mitchell-Swain-Haywood-Buncombe-Catawba-
Rowan-Graham-Northern Jackson-Macon-Southern Jackson-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-
530 AM EDT Wed May 16 2018

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

.DAY ONE...Today and Tonight.

Numerous to widespread heavy rain showers and thunderstorms are
expected to continue impacting the area through tonight. In addition
to the potential for cloud-to-ground lightning, gusty winds, and
small hail, slow-moving or training cells could produce locally
excessive rainfall and flash flooding. While very heavy rainfall is
possible everywhere across the area, the best chance for flash
flooding will exist near the southern Blue Ridge escarpment.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.

..Thursday...Heavy rain possible. Numerous to widespread showers and
thunderstorms are expected to continue through Thursday. At least a
localized flash flood threat is expected, especially in areas that
receive heavy rainfall through tonight.
..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...

Skywarn spotters are requested to forward any reports of flash
flooding to our office.

Lane

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
216 PM EDT WED MAY 16 2018

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

1030 AM     FLOOD            2 S HENDERSONVILLE      35.30N 82.46W
05/16/2018                   HENDERSON          NC   SOCIAL MEDIA

            ROADS CLOSED DUE TO FLOODING IN THE VICINTY OF KANUGA
            ROAD AND ERKWOOD DRIVE.

1100 AM     FLOOD            1 SSE HENDERSONVILLE    35.31N 82.46W
05/16/2018                   HENDERSON          NC   SOCIAL MEDIA

            ROADS FLOODED IN THE VICINITY OF SOUTH MAIN AND
            SPARTANBURG HIGHWAY.

&&

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
222 PM EDT WED MAY 16 2018

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

1030 AM     FLOOD            5 E BREVARD             35.24N 82.64W
05/16/2018                   TRANSYLVANIA       NC   SOCIAL MEDIA

            ROADS CLOSED DUE TO FLOODING AROUND CASECADE LAKE ROAD
            AND MERRILL LANE.

&&

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
229 PM EDT WED MAY 16 2018

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

1100 AM     FLOOD            2 SE BREVARD            35.22N 82.71W
05/16/2018                   TRANSYLVANIA       NC   BROADCAST MEDIA

            SWOLLEN FRENCH BROAD RIVER WASHED OUT A SECTION OF WILSON
            ROAD.

&&

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
233 PM EDT WED MAY 16 2018

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

1100 AM     FLOOD            4 SSW BREVARD           35.18N 82.76W
05/16/2018                   TRANSYLVANIA       NC   BROADCAST MEDIA

            HANNAH FORD AND ISLAND FORD ROADS CLOSED DUE TO FLOODING.

&&

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
316 PM EDT WED MAY 16 2018

NCZ037-057-071-072-082-162015-
Rowan NC-Davie NC-Union NC-Mecklenburg NC-Cabarrus NC-
316 PM EDT WED MAY 16 2018

...THUNDERSTORMS WITH TORRENTIAL RAINFALL WILL IMPACT CABARRUS...
SOUTHEASTERN DAVIE...SOUTHEASTERN MECKLENBURG...ROWAN AND NORTHERN
UNION COUNTIES UNTIL 415 PM EDT...

At 314 PM EDT, Doppler radar indicated showers and thunderstorms
with torrential rainfall along a line extending from 4 miles north
of Salisbury to 6 miles southwest of Downtown Concord to 8 miles
west of Monroe, moving northeast at 15 mph. These showers were
producing rainfall at rates of 1 to 2 inches per hour.

Locations to be impacted include...
Kannapolis, Downtown Concord, Salisbury, Monroe, Mocksville, West
Concord, Matthews, Mint Hill, Indian Trail and Stallings.

Deep ponding of water will develop in low lying areas and normally
poor drainage locations. Flooding could develop rapidly, however, if
the line of thunderstorms slows down or stalls.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall may flood areas with poor drainage, such as
ditches and underpasses. Avoid these areas and do not cross flooded
roads. Water levels of small streams may also rise rapidly. Seek
higher ground if threatened by flood waters.

&&

LAT...LON 3550 8030 3519 8051 3516 8044 3520 8028
      3508 8034 3491 8072 3541 8072 3593 8053
      3598 8041 3596 8038 3589 8037 3588 8042
      3584 8039 3583 8049 3577 8045 3574 8046
      3571 8033 3568 8033 3559 8021 3551 8018
TIME...MOT...LOC 1914Z 221DEG 14KT 3573 8051 3534 8066 3503 8068

HG

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
324 PM EDT WED MAY 16 2018

GAZ029-162015-
Elbert GA-
324 PM EDT WED MAY 16 2018

...A SERIES OF THUNDERSTORMS WITH TORRENTIAL RAINFALL WILL IMPACT
ELBERT COUNTY UNTIL 415 PM EDT...

At 321 PM EDT, Doppler radar was tracking a series of thunderstorms
with torrential rainfall moving northeast at 15 to 20 mph across
central Elbert County.

Locations to be impacted include...
Elberton, Nancy Hart State Park, Middleton, Russell State Park, Lake
Russell, Rock Branch, Fortsonia, Sweet City, Ruckersville and Dewy
Rose.

Very heavy rainfall rates of 1 to 2 inches per hour will be possible
in these areas. Deep ponding of water will develop in low lying
areas and streams may approach bankfull.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall may flood areas with poor drainage, such as
ditches and underpasses. Avoid these areas and do not cross flooded
roads. Water levels of small streams may also rise rapidly. Seek
higher ground if threatened by flood waters.

&&

LAT...LON 3399 8283 3398 8286 3401 8291 3401 8293
      3403 8294 3404 8298 3409 8303 3428 8281
      3429 8277 3427 8275 3421 8274 3415 8272
      3413 8267 3409 8264 3407 8264 3406 8263
      3398 8275 3397 8278
TIME...MOT...LOC 1921Z 221DEG 14KT 3401 8289

HG