What forecasters said that day
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Greenville-Spartanburg, SC wrote its last area forecast discussion before the first event at Aug 5, 1:35 PM EST, 55 minutes earlier.
Area forecast discussion, Aug 5, 1:35 PM EST, 55 minutes before
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
235 PM EDT Wed Aug 5 2020
.SYNOPSIS...
Expect a more typical summertime pattern of mainly afternoon and
evening showers and thunderstorms through early next week.
Temperatures will be near normal for this time of year.
&&
.NEAR TERM /THROUGH THURSDAY/...
As of 233 PM: Deep convection underway across the mtns, but still
quiet east of the Blue Ridge. Environment is characterized by
2000-3500 J/kg of sfc-based CAPE and dCAPE of at least 800 J/kg, so
there is some concern for a few pulse severe storms this afternoon
and evening as updrafts become more robust. No major changes at
this time, other than a few tweaks to the precip probs.
The weather situation remains persistent over the next 24 hours
with a SW flow aloft as an upper trof axis remains to our west. One
weak short wave will move slowly overhead this evening, while low
level flow remains light from the S to SE. This should keep some
convection going well into the overnight period, possibly all night
long near the Blue Ridge Escarpment where some weak mechanical lift
will persist. Thus, we hold onto some small precip chances. Min
temps will be near normal. Thursday should turn out similar to
today, with another favorable environment for deep convection
that initiates over the higher terrain by midday and expands from
there. Precip probs should be well above climo again. Sfc-based
CAPE in excess of 2500 J/kg, sfc-delta Theta-e in excess of 30,
and low shear point to another afternoon with possible pulse severe
storms. High temps will be near normal.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
As of 200 pm EDT Wednesday: Thursday night into Friday, an
upper trough will continue to set up shop over the eastern CONUS
with the axis of it just west of the southern Appalachians.
With an associated frontal boundary expected to remain stalled
across the eastern fringe of the cwa, isolated showers and
thunderstorms should linger through the overnight and early
morning hours on Friday, mainly in the mountains and NC
Piedmont. With the help from the right entrance region of a 200
mb jet streak located over the central Appalachians on the
eastern side of the trough, some divergence and forcing aloft
will kick-off a round of convective development early Friday
afternoon, starting in the higher elevations. With the front
still expected to remain stalled near the far eastern zones and
diurnal instability in place, scattered convective coverage and
above climo pops will be likely, especially from the mountains
to the NC Piedmont. Most of the activity on Friday will be
diurnal, but the axis of the trough gradually moves over the
region late Friday into early Saturday before lifting out to the
north and east. This opens the door for a few showers and
storms to linger past sunset Friday. As for Saturday, the front
will sag southward and the overall flow pattern flattens out a
bit and begins to become more zonal. Drier air will filter in as
a W to NW flow overtakes the area. With higher heights building
in from the south, temperatures will be at or slightly above
climo for Saturday. Not to mention, convective development will
be somewhat suppressed compared to Friday, but moderate
instability from daytime heating and PWAT values >1.25" for most
locations should keep isolated to scattered diurnal convective
coverage in the forecast during the first half of the weekend.
Model guidance picks up on a wave or two of elongated shortwaves
to move across the cwa during the same time period and allows
pops on Saturday to stay a tad bit above climo due to the mid-
level energy and typical summertime nature.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
As of 2pm EDT Wednesday: Not a lot of change in the day-to-day
sensible weather Sunday through Wednesday as near climo summertime
conditions continue. High and low temperatures vary by a few degrees
each day, along with generally light winds, and at least some chance
for afternoon thunder each day.
Some weak embedded shortwaves in WNW upper flow will, at times, give
a little forcing that will elevate POPs to above climo levels. At
the same time, weak surface features do not give any strong fetch of
new moisture into the area. So CAPE will remain at 1000 to 2000
j/kg in the afternoons, along with low-levels of deep-shear, to give
limited chances for severe. Most likely severe weather will be
isolated microburst activity, typical of this time of year.
EC and GFS models agree on general weak dynamical pattern, with the
latest GFS model having a stronger shortwave entering the eastern
CONUS Monday night. However, most of the energy with this wave
crosses well north of the CWA, with only some difficult-to-nail-down
increase in POPs Tuesday evening.
&&
.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
At KCLT and Elsewhere: VFR through the evening hours outside
of scattered/numerous thunderstorms. All sites get a TEMPO for
thunderstorms with an MVFR restriction based on the latest model
guidance, mainly during the mid/late afternoon hours. Guidance
suggests the convection will carry on into the overnight, so
this will be re-evaluated and amended later on. Wind should be
light from the SE to S with scattered cu away from storms and
outflows. Low level moisture will remain rich overnight. Valley
fog looks like a near certainty, so KAVL was taken down to at least
LIFR in the pre-dawn hours. Other sites could also have an MVFR or
IFR restriction at that time, but confidence is lower. Expect more
of the same on Thursday, with light SW wind and more convection
from midday onward.
Outlook: Afternoon/evening showers and thunderstorms will be
possible thru the rest of the work week. Morning restrictions will
also be possible, especially over the usual mountain valleys.
Confidence Table...
18-24Z 00-06Z 06-12Z 12-18Z
KCLT High 100% High 100% Med 78% Med 79%
KGSP High 100% High 100% High 85% High 88%
KAVL High 100% Med 75% Med 77% High 83%
KHKY High 100% High 90% Med 67% High 81%
KGMU High 100% High 100% Med 69% High 87%
KAND High 100% High 100% High 88% High 81%
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...DEO
NEAR TERM...PM
SHORT TERM...CAC
LONG TERM...WJM
AVIATION...PMHazardous weather outlook, Aug 5, 3:49 AM EST, 10 hours 41 minutes before
Hazardous Weather Outlook
National Weather Service Greenville-Spartanburg SC
449 AM EDT Wed Aug 5 2020
GAZ010-017-018-026-028-029-NCZ033-035>037-048>053-056>059-062>065-
068>072-082-501>510-SCZ001>014-019-060900-
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 NC-
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-Union SC-Chester-Greenwood-
449 AM EDT Wed Aug 5 2020
This Hazardous Weather Outlook is for northeast Georgia, Piedmont
North Carolina, western North Carolina, and Upstate South Carolina.
.DAY ONE...Today and tonight.
Scattered to numerous thunderstorms are expected to develop across
the region this afternoon and evening. Any of these thunderstorms may
produce cloud to ground lightning, heavy downpours, and gusty winds.
One or two of the thunderstorms may become severe, producing damaging
wind gusts.
.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.
No hazardous weather is expected at this time.
.SPOTTER INFORMATION STATEMENT...
None.
HG
In the hours before
Special weather statement, Aug 5, 1:37 PM EST, 53 minutes before
Special Weather Statement
National Weather Service Greenville-Spartanburg SC
237 PM EDT Wed Aug 5 2020
GAZ010-051915-
Rabun GA-
237 PM EDT Wed Aug 5 2020
...A STRONG THUNDERSTORM WILL IMPACT EASTERN RABUN COUNTY UNTIL 315
PM EDT...
At 236 PM EDT, Doppler radar was tracking a strong thunderstorm near
Clayton, or near Tiger, moving northeast at 20 mph.
Locations to be impacted include...
Clayton, Mountain City, Tiger, Sky Valley, Lakemont, Black Rock
Mountain State Park and Pine Mountain.
Wind gusts up to 45 mph and pea size hail 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.
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 3484 8353 3500 8333 3500 8311 3499 8310
3496 8312 3493 8311 3493 8316 3492 8316
3489 8320 3488 8321 3488 8324 3487 8324
3486 8325 3485 8325 3485 8327 3483 8327
3477 8340
TIME...MOT...LOC 1836Z 230DEG 17KT 3484 8340
KRENTZSpecial weather statement, Aug 5, 1:52 PM EST, 38 minutes before
Special Weather Statement
National Weather Service Greenville-Spartanburg SC
252 PM EDT Wed Aug 5 2020
SCZ012-051930-
Laurens SC-
252 PM EDT Wed Aug 5 2020
...A STRONG THUNDERSTORM WILL IMPACT EAST CENTRAL LAURENS COUNTY
UNTIL 330 PM EDT...
At 251 PM EDT, Doppler radar was tracking a strong thunderstorm 12
miles east of Laurens, or near Joanna, moving northeast at 15 mph.
Locations to be impacted include...
Clinton, Joanna and Kinards.
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...
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 3447 8194 3456 8176 3456 8174 3455 8172
3456 8170 3455 8169 3456 8168 3453 8165
3452 8165 3446 8170 3444 8173 3437 8178
3435 8181 3435 8183
TIME...MOT...LOC 1851Z 229DEG 14KT 3445 8182
KRENTZSpecial weather statement, Aug 5, 2:10 PM EST, 20 minutes before
Special Weather Statement
National Weather Service Greenville-Spartanburg SC
310 PM EDT Wed Aug 5 2020
SCZ011-019-051945-
Abbeville SC-Greenwood SC-
310 PM EDT Wed Aug 5 2020
...A STRONG THUNDERSTORM WILL IMPACT SOUTHEASTERN ABBEVILLE AND WEST
CENTRAL GREENWOOD COUNTIES UNTIL 345 PM EDT...
At 309 PM EDT, Doppler radar was tracking a strong thunderstorm 6
miles southeast of Abbeville, moving northeast at 15 mph.
Locations to be impacted include...
Greenwood, Promised Land and Bradley.
Wind gusts up to 40 mph and pea size hail 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.
&&
LAT...LON 3404 8229 3412 8239 3427 8225 3415 8207
TIME...MOT...LOC 1909Z 227DEG 13KT 3413 8227
KRENTZ
Special weather statement, Aug 5, 2:26 PM EST, 4 minutes before
Special Weather Statement
National Weather Service Greenville-Spartanburg SC
326 PM EDT Wed Aug 5 2020
SCZ013-052000-
Union SC-
326 PM EDT Wed Aug 5 2020
...A STRONG THUNDERSTORM WILL IMPACT WEST CENTRAL UNION COUNTY UNTIL
400 PM EDT...
At 326 PM EDT, Doppler radar was tracking a strong thunderstorm 12
miles southwest of Union, or 7 miles west of Rose Hill State Park.
This storm was nearly stationary.
Locations to be impacted include...
Cross Keys and Sedalia.
Wind gusts up to 40 mph and pea size hail 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.
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 3457 8177 3457 8180 3458 8180 3458 8181
3459 8182 3459 8184 3460 8184 3460 8185
3468 8182 3469 8181 3462 8171 3456 8176
TIME...MOT...LOC 1926Z 141DEG 4KT 3461 8180
KRENTZ