Flash Flood Warning 10, NWS Greenville-Spartanburg, SC

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
1051 AM EDT Fri Apr 19 2019

.SYNOPSIS...
A strong cold front will move through the forecast area today
bringing showers and thunderstorms to the region. There is a
good chance that some of these storms could become severe as
the front moves through the area. Cooler temperatures and
lingering showers are expected behind the front. Temperatures
will warm again by early next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 1030 AM: Band of precip with embedded linear convective
segments continues to progress eastward into the CWFA. Previous
thinking w.r.t. severe potential remains essentially the same,
and all of the ingredients for high-shear/low-CAPE impacts still
are present or progged to come together by early afternoon. A
number of minor wind damage reports have already been received
from areas affected by the better organized segments, with minor
flood impacts also having developed in the areas near the southern
facing Blue Ridge Escarpment. A Tornado Watch just was issued to
cover the area that has not already seen the stabilizing impacts
of the rain, and is valid until 5 PM EDT. Have updated timing of
PoPs and thunder mention across the CWFA, and temp/dewpt trends
were closely tied to the HRRR output, which is our best choice in
such a rapidly changing environment.

Overall, a closed upper low in the Mid-South will slow down somewhat
while the surrounding trough begins to acquire a negative tilt. This
will likely do two things. One, it will provide a significant
couplet of strong synoptic ascending and descending air associated
with a 120 kt jet streak overhead. Two, the slowing should allow
for diurnal instability over the eastern half of the area, that is,
the area where activity has not yet really fired, to be able to tap
into strong shear (0-1 km BS of 40+ kts) just above the surface
(two key ingredients for severe weather). The leading line of
convection (QLCS) looks to have the greatest widespread severe
threat prior to 4 pm, with severe winds (in excess of 58 mph)
the primary threat due to the potential for a strong rear inflow
jet associated with the QLCS with a secondary threat for both
tornadoes and severe hail. SPC Moderate Risk remains in effect
for the I-77 corridor including Charlotte meaning that scattered
severe thunderstorms are likely. The severe risk gradually decreases
heading west across the FA, but the latest Day 1 outlook is more
or less identical to the previous issuance within the CWFA. The
mode of convection is more up for debate after the initial line as
model guidance does show a secondary frontal feature following the
main one, but the question remains as to how much instability will
be left and how any convection may organize along or out ahead of
it. There remains enough model support to expect some disorganized
convection moving generally SW to NE as llvl flow veers to the SW
with the upper low nearing the FA later this afternoon. Can't rule
out a few supercell thunderstorms developing ahead or along the
main line of convection (if there are breaks) or mini supercells
behind the system, with instability being limiting factor at
that time.  The slow moving nature of convection with the main
line of convection in particular will cause at least isolated
hydro issues to small streams and roadways (WPC slight risk for
excessive rainfall across the region). The strong southerly winds
along and ahead of this system will support gusty winds across
the high elevations, especially SW mountains where a wind advisory
has been posted and continues through noon.

Most areas will see rain and thunderstorms come to an end by this
evening as the main forcing exits NE of the region. However, the
cold core upper low will support snow levels falling to around 4K
feet and potential for accumulating snows at this level with several
inches possible above 5K feet, especially where the best upslope
flow (from the SW) overlaps with good synoptic lift and moisture
across the SW mtns. As of now the main winter weather impacts
appear to be above 5K feet so any winter products will be shelved
for now, but considered on future shifts. Temps for most areas
will only fall into the 40s and 50s (30s higher mtn elevations)
due to continued breezy conditions, so frost should not be an issue.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
As of 235 AM EDT Friday: the short-term fcst picks up at 12z on
Saturday with an impressive upper low centered just to our north
as steep upper ridging spreads over the Western CONUS. Because
this system is essentially cut-off from the northern-stream upper
flow, it will push eastward very slowly and is not expected to
move off the Atlantic Coast until the very end of the period on
Monday. At the sfc, a substantial low pressure system will be
centered to our NNW and over the Ohio River Valley as the cold
front associated with it moves offshore. Over the next 24hrs or
so, the low will remain nearly stationary as a substantial plum
of deep-lyr moisture spreads over much of the CWFA from the west.
The latest model guidance continues to open up the low by Sunday
morning as the system gradually lifts NE of the fcst area and
drier air moves back over the area. For the rest of the period,
drier high pressure centered over the Northern Gulf of Mexico
will persist over the Southeast. As for the sensible fcst, we
will likely have some lingering precip on Sat with the remainder
of the period being dry. With the impressive cold-air advection
expected across the region and unusually low thickness values,
some snow flurries are expected over the higher elevations early
Sat and early Sun. Some accumulating snow is possible above 3500
ft, with a better chance above 5000ft. At this time, I do not
anticipate any winter hazard products will be needed, but if
expected snow amounts trend upwards then hazards cannot be ruled
out. The resulting windy conditions should help inhibit any frost
formation across the active zones (which is everywhere except the
Northern NC Mountains). Temps should warm back into the upper 60s
to low 70s across the lower elevations on Sunday, with more warming
as we move into the extended period.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
As of 245 PM EDT Thursday: Upper low over the Mid-Atlantic will
continue to lift north, with high pressure building in and
increasing thicknesses. Temperatures will increase through the
extended, 5 to maybe even 10 degrees above seasonal. A shortwave
spinning around the upper low may bring some showery activity or
even possible thunderstorms Tuesday afternoon, GFS a little stronger
with this idea than ECMWF. Next system gearing up over the Rockies
will push off into the Plains sometime midweek, but there are some
very significant timing differences between the global models, so
frankly opted to keep a fairly generic blend through the end of the
period and into the new day 7. As a note to readers, depending on
how near-term activity shapes up tonight, the extended forecast may
not be updated until Friday afternoon.

&&

.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
At KCLT and elsewhere: Rapidly deteriorating conds expected between
12Z and 18Z associated with a dynamic storm system to move through
the region. Model guidance shows that the strong line of showers and
thunderstorms (QLCS) approaching across the deep south will hold
together and even intensify east of I-26 and especially near the I-
77 corridor, including KCLT. Brief SW/W gusts in excess of 40 kts
is possible with the QLCS. Light to occasionally moderate LLWS is
possible, especially between 15Z and 20Z. LLWS issues may linger at
KAVL behind this time as winds veer to the SW. A secondary impulse
of showers and embedded thunderstorms associated with the leading
edge of the upper low are possible just about anywhere between 18Z
and 00Z.

Outlook: Improving conditions are expected early Saturday. Spotty
restrictions cannot be ruled out over the mtns as an upper low
passes by on Saturday.

Confidence Table...

            15-21Z        21-03Z        03-09Z        09-12Z
KCLT       High  85%     High  87%     High  91%     High  87%
KGSP       Med   71%     High  89%     Med   77%     High  80%
KAVL       Med   75%     High  89%     Med   64%     High  90%
KHKY       High  91%     High  87%     Med   75%     High  84%
KGMU       Med   73%     High  91%     Med   77%     High  82%
KAND       Med   79%     Med   77%     High  87%     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...Wind Advisory until noon EDT today for NCZ033-048>052-058-059-
     062>064.
SC...None.

&&

SYNOPSIS...JPT
NEAR TERM...Munroe/Wimberley
SHORT TERM...JPT
LONG TERM...TDP
AVIATION...Munroe

Hazardous Weather Outlook
National Weather Service Greenville-Spartanburg SC
1056 AM EDT Fri Apr 19 2019

GAZ028-029-NCZ035>037-056-057-068>072-082-501>510-SCZ002-003-005>014-
019-201500-
Hart-Elbert-Alexander-Iredell-Davie-Catawba-Rowan-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-Pickens Mountains-Greenville Mountains-
Greater Pickens-Greater Greenville-Spartanburg-Cherokee-York-
Anderson-Abbeville-Laurens-Chester-Greenwood-
1056 AM EDT Fri Apr 19 2019

...TORNADO WATCH 88 IN EFFECT UNTIL 5 PM EDT THIS AFTERNOON...

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

.DAY ONE...Today and tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Tornado Watch.

Additionally, periods of heavy rain will occur through this
afternoon. Isolated flash flooding may occur, especially in poorly
drained areas, areas of hilly terrain, or in urban environments.

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

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotters are requested to forward any reports of large hail,
damaging winds, tornadoes, or flash flooding to our office.

NCZ048>053-058-059-062>064-201500-
Madison-Yancey-Mitchell-Swain-Haywood-Buncombe-Graham-
Northern Jackson-Macon-Southern Jackson-Transylvania-
1056 AM EDT Fri Apr 19 2019

...WIND ADVISORY IN EFFECT UNTIL NOON EDT TODAY ABOVE 3500 FEET...

This Hazardous Weather Outlook is for western North Carolina.

.DAY ONE...Today and tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Wind Advisory.

Periods of heavy rain also will occur through early afternoon.
Isolated flooding may occur, especially on small creeks and streams,
areas of hilly terrain, or in urban environments.

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

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

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

GAZ010-017-018-026-NCZ065-SCZ001-004-201500-
Rabun-Habersham-Stephens-Franklin-Henderson-Oconee Mountains-
Greater Oconee-
1056 AM EDT Fri Apr 19 2019

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

.DAY ONE...Today and tonight.

Periods of heavy rain will occur through early afternoon. Isolated
flooding may occur, especially on small creeks and streams, areas of
hilly terrain, or in urban environments.

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

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotters are requested to forward any reports of flooding to our
office.

NCZ033-201500-
Avery-
1056 AM EDT Fri Apr 19 2019

...WIND ADVISORY IN EFFECT UNTIL NOON EDT TODAY ABOVE 3500 FEET...
...TORNADO WATCH 88 IN EFFECT UNTIL 5 PM EDT THIS AFTERNOON...

This Hazardous Weather Outlook is for western North Carolina.

.DAY ONE...Today and tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Tornado Watch.
   Wind Advisory.

Periods of heavy rain also will occur through early afternoon.
Isolated flooding may occur, especially on small creeks and streams,
areas of hilly terrain, or in urban environments.

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

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotters are requested to forward any reports of large hail,
damaging winds, tornadoes, or flash flooding to our office.

Wimberley

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
1149 AM EDT Fri Apr 19 2019

NCZ035-502-191615-
Greater Caldwell NC-Alexander NC-
1149 AM EDT Fri Apr 19 2019

...A STRONG THUNDERSTORM WILL IMPACT WESTERN ALEXANDER AND
SOUTHEASTERN CALDWELL COUNTIES UNTIL 1215 PM EDT...

At 1149 AM EDT, Doppler radar was tracking a strong thunderstorm 6
miles north of Hickory, or near Lake Hickory, moving northeast at 40
mph.

Locations to be impacted include...
Taylorsville, Granite Falls, Bethlehem, Lake Hickory, Rhodhiss,
Sawmills, Lake Rhodhiss, Northlakes, Little River In Alexander County
and Ellendale.

Wind gusts up to 40 mph, pea size hail and very heavy rainfall rates
up to 2 inches per hour 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.

&&

A Tornado Watch remains in effect until 500 PM EDT for western and
the Piedmont of North Carolina.

LAT...LON 3603 8109 3581 8126 3580 8134 3578 8136
      3577 8135 3576 8137 3579 8147 3604 8137
      3602 8134 3600 8133 3603 8127 3604 8120
      3603 8118 3603 8117 3604 8113
TIME...MOT...LOC 1549Z 204DEG 35KT 3583 8136

MOORE

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1207 PM EDT FRI APR 19 2019

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

1200 PM     FLASH FLOOD      5 NW CARNESVILLE        34.42N 83.30W
04/19/2019                   FRANKLIN           GA   LAW ENFORCEMENT

            MULTIPLE ROADS FLOODED. TWO PAVED ROADS WERE WASHED OUT
            DUE TO SINKHOLES.

&&

SWILKINS

Special Weather Statement
National Weather Service Greenville-Spartanburg SC
1208 PM EDT Fri Apr 19 2019

NCZ508-SCZ007-008-191645-
Greater Rutherford NC-Cherokee SC-Spartanburg SC-
1208 PM EDT Fri Apr 19 2019

...A CLUSTER OF THUNDERSTORMS WILL IMPACT SOUTHEASTERN RUTHERFORD...
CENTRAL SPARTANBURG AND NORTHWESTERN CHEROKEE COUNTIES UNTIL 1245 PM
EDT...

At 1208 PM EDT, Doppler radar indicated the leading edge of a cluster
of thunderstorms along a line extending from 5 miles south of Forest
City to 8 miles northwest of Laurens, and moving north at 60 mph.

Locations to be impacted include...
Spartanburg, Forest City, Boiling Springs SC, Woodruff, Pacolet,
Cowpens, Mayo, Roebuck, Chesnee and Pacolet Mills.

Wind gusts up to 50 mph and very heavy rainfall rates up to 2 inches
per hour will be possible in these areas.

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.

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.

&&

A Tornado Watch remains in effect until 500 PM EDT for western and
the Piedmont of North Carolina...and Upstate South Carolina.

LAT...LON 3472 8207 3531 8192 3536 8171 3519 8177
      3518 8177 3518 8172 3488 8174 3483 8179
      3476 8180 3468 8204
TIME...MOT...LOC 1608Z 194DEG 53KT 3526 8190 3460 8212

TDP

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1209 PM EDT FRI APR 19 2019

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

1200 PM     FLASH FLOOD      TOCCOA                  34.58N 83.32W
04/19/2019                   STEPHENS           GA   LAW ENFORCEMENT

            5 ROADS CLOSED AND SEVERAL OTHERS FLOODED DUE TO CREEKS
            RISING.

&&

SWILKINS

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1210 PM EDT FRI APR 19 2019

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

1205 PM     FLASH FLOOD      WALHALLA                34.77N 83.06W
04/19/2019                   OCONEE             SC   LAW ENFORCEMENT

            NUMEROUS ROADS FLOODED ACROSS THE COUNTY AND CREEKS
            EXCEEDING THEIR BANKS. A FEW PARKED CARS WERE FLOODED.

&&

SWILKINS

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1212 PM EDT FRI APR 19 2019

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

0825 AM     TSTM WND DMG     AVALON                  34.50N 83.19W
04/19/2019                   STEPHENS           GA   LAW ENFORCEMENT

            TREES DOWN BLOCKING ROADS.

&&

SWILKINS