Alert archive / South Carolina / Special Weather Statements in 2017

Special Weather Statement, NWS Columbia, SC

August 31, 2017Kershaw County, South Carolina

NWS Columbia, SC issued this special weather statement at Aug 31, 2017, 4:02 PM EDT for Kershaw County, South Carolina. It was in force for 58 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Aug 31, 2017, 4:02 PM EDT (20:02 UTC)
Expired: Aug 31, 2017, 5:00 PM EDT
In force: 58 min
Issued by: NWS Columbia, SC

County Kershaw County, SC

The radar

The Columbia radar (KCAE), 69 km from the middle of the area, began a volume at 20:02 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Greensboro/Hi Pt, NC (KGSO), launched 12:00Z, 8.0 hours before the alert went out and 192 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1203 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: 45 m²/s²
0-3 km storm-relative helicity: 31 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

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What forecasters said that day

The local office's own words before this special weather statement went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Columbia, SC wrote its last area forecast discussion before this special weather statement went out at Aug 31, 2:30 PM EDT, 1 hour 32 minutes earlier.

Area forecast discussion, Aug 31, 2:30 PM EDT, 1 hour 32 minutes before

Area Forecast Discussion
National Weather Service Columbia SC
230 PM EDT Thu Aug 31 2017

.SYNOPSIS...
Shower and thunderstorm chances will continue through the end
of the week as the remnants of TS Harvey bring increasing
moisture to the region. Drier air will filter into the region by
late in the Holiday weekend with temperatures near normal. A
cold front will approach from the west around the middle of next
week.

&&

.NEAR TERM /THROUGH TONIGHT/...
The remnants of Tropical Storm Harvey will lift from the lower
Mississippi River Valley toward the Tennessee River Valley
bringing increased moisture. A warm front over central GA this
afternoon will lift north across the area tonight. Already
seeing moderate instability over the CSRA into the Central
Midlands. Mid-level short wave energy combined with moderate
instability and Precipitable water values between 2.0 and 2.3
inches allowing convection to develop this afternoon. Scattered
to numerous showers and thunderstorms are expected into the
evening. Could see a few severe storms...especially across the
southern Midlands and CSRA where instability and shear is
greatest. Damaging winds appear to be the main threat. An
isolated tornado threat cannot be ruled out. Afternoon
temperatures will peak in the lower 80s north to near 90 south.

Scattered showers and thunderstorms are expected to continue
through the early portions of tonight, before becoming more
isolated late tonight. With the energy associated with the
remnants of Harvey rotating around the eastern side of the low,
and with a weak warm front lingering across the Midlands
overnight...can not rule out a few strong storms tonight,
especially over the western portions of the forecast area.
Overnight lows will be in the lower 70s.

&&

.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
On Friday, the remnants of Harvey will push mainly over the TN
Valley, while a cold front begins pushing southward towards the
forecast area through the day. With the increased shear along
the front as it moves into the area, expect another round of
stronger storms to develop during the afternoon hours. There is
a risk of severe storms during the afternoon and evening hours.
The latest Day 2 severe weather outlook from SPC has much of the
northern half of the state in Slight Risk with the rest of the
state in Marginal Risk for Friday. The cold front should move
through the area late Friday night, with storms still possible
along the front. Some drier air may begin filtering into the
area from the west late Friday night.

Temperatures Friday will range from the lower to middle 80s
north to near 90 across the southern Midlands and CSRA. most of
the area in warm sector. Readings on Friday night slightly
cooler with temperatures in the upper 60s to lower 70s.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
Drier airmass moving into the area behind the cold front on
Saturday will allow for diminished rain chances as the day goes
on. Dry weather expected to continue into Tuesday as high
pressure settles into the region. Latest GFS indicating
moisture return on Wednesday into Thursday ahead of the next
upper system. Temperatures generally close to normal Saturday
through Wednesday, and a little below normal Thursday.

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
Scattered convection expected to increase in coverage into the
evening as the area of storms over GA moves east into the CSRA
and Midlands. Have indicated tempo at all TAF sites through
01/00Z. Should see convection decreasing after sunset as
instability weakens...though at least isolated convection is
possible overnight. Models indicate potential for stratus with
MVFR/IFR conditions to develop overnight...then improving to VFR
by late morning. Scattered to numerous showers and thunderstorms
should once again develop Friday afternoon.

EXTENDED AVIATION OUTLOOK...Showers and thunderstorms expected
across the area Friday afternoon into Saturday as the remnants
of Harvey lifts north from the TN Valley into the Ohio River
Valley.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
GA...None.
SC...None.

&&

Hazardous weather outlook, Aug 31, 3:50 AM EDT, 12 hours 12 minutes before

Hazardous Weather Outlook
National Weather Service Columbia SC
350 AM EDT Thu Aug 31 2017

GAZ040-063>065-077-SCZ015-016-018-020>022-025>031-035>038-041-010800-
Lincoln-McDuffie-Columbia-Richmond-Burke-Lancaster-Chesterfield-
McCormick-Newberry-Fairfield-Kershaw-Edgefield-Saluda-Lexington-
Richland-Lee-Aiken-Sumter-Barnwell-Orangeburg-Calhoun-Clarendon-
Bamberg-
350 AM EDT Thu Aug 31 2017

This Hazardous Weather Outlook is for the Midlands of South Carolina
and the Central Savannah River area of Georgia.

.DAY ONE...Today and Tonight.

Scattered showers and thunderstorms this afternoon and tonight may
bring strong winds and brief heavy rainfall to the area.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday.

Additional showers and thunderstorms remain possible on Friday as the
remnants of Harvey move north of the area, and a cold front moves
southward. Isolated severe storms with strong winds and heavy
rainfall will be possible on Friday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

In the hours before

Special weather statement, Aug 31, 2:42 PM EDT, 1 hour 20 minutes before

Special Weather Statement
National Weather Service Columbia SC
242 PM EDT THU AUG 31 2017

GAZ063>065-311930-
Richmond-McDuffie-Columbia-
242 PM EDT THU AUG 31 2017

...A STRONG THUNDERSTORM WILL AFFECT COLUMBIA...MCDUFFIE AND CENTRAL
RICHMOND COUNTIES...

At 241 PM EDT, a strong thunderstorm was located near Camak, or near
Warrenton, moving east at 25 mph.

Winds up to 40 mph are possible with this storm.

Locations impacted include...
Grovetown, Evans, Thomson, Fort Gordon, Martinez, Hephzibah, Harlem,
Blythe and Dearing.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

LAT...LON 3366 8244 3365 8243 3368 8236 3369 8235
      3369 8222 3363 8220 3359 8214 3332 8199
      3328 8216 3330 8218 3327 8228 3331 8234
      3331 8239 3334 8244 3335 8255 3341 8255
      3346 8259 3357 8263
TIME...MOT...LOC 1841Z 251DEG 22KT 3344 8259

CJR

Local storm report, Aug 31, 3:50 PM EDT, 12 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE COLUMBIA SC
350 PM EDT THU AUG 31 2017

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

0330 PM     TSTM WND DMG     1 NNW HARLEM            33.43N 82.32W
08/31/2017                   COLUMBIA           GA   LAW ENFORCEMENT

            COLUMBIA COUNTY SHERIFF REPORTED TREE IN
            ROADWAY AT N. FAIRFIELD DRIVE AND SAWDUST
            ROAD IN HARLEM.

&&

RC

Special weather statement, Aug 31, 4:02 PM EDT, 0 minutes before

Special Weather Statement
National Weather Service Columbia SC
402 PM EDT THU AUG 31 2017

SCZ015-021-022-312100-
Fairfield-Lancaster-Kershaw-
402 PM EDT THU AUG 31 2017

...A STRONG THUNDERSTORM WILL AFFECT NORTHEASTERN FAIRFIELD...
SOUTHERN LANCASTER AND CENTRAL KERSHAW COUNTIES...

At 402 PM EDT, a strong thunderstorm was located over Winnsboro,
moving east at 25 mph.

Wind gusts up to 50 mph and pea size hail are possible with this
storm.

Locations impacted include...
Winnsboro, Kershaw, Heath Springs, Ridgeway and Winnsboro Mills.

LAT...LON 3469 8053 3432 8042 3427 8110 3448 8113
      3455 8094 3454 8088 3457 8087
TIME...MOT...LOC 2002Z 251DEG 22KT 3438 8104

CJR

The office that day

Everything else NWS Columbia, SC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 31, 3:26 PM EDT	Severe Thunderstorm Warning	CAE	Aiken, Edgefield, McCormick	64 min
Aug 31, 4:00 PM EDT	Severe Thunderstorm Warning	CAE	Aiken, Barnwell, Orangeburg	37 min
Aug 31, 4:26 PM EDT	Special Weather Statement	CAE	Aiken	34 min
Aug 31, 4:29 PM EDT	Special Weather Statement	CAE	Calhoun	46 min
Aug 31, 4:41 PM EDT	Severe Thunderstorm Warning	CAE	Kershaw, Lee	64 min
Aug 31, 4:53 PM EDT	Special Weather Statement	CAE	Lexington	37 min
Aug 31, 5:06 PM EDT	Severe Thunderstorm Warning	CAE	Chesterfield, Kershaw	54 min
Aug 31, 5:12 PM EDT	Severe Thunderstorm Warning	CAE	Lee	48 min
Aug 31, 5:14 PM EDT	Special Weather Statement	CAE	Bamberg	46 min
Aug 31, 5:33 PM EDT	Special Weather Statement	CAE	Clarendon	57 min
Aug 31, 6:17 PM EDT	Special Weather Statement	CAE	Clarendon	28 min
Aug 31, 2:42 PM EDT	Special Weather Statement	CAE	Columbia, McDuffie, Richmond	48 min

Nearby

Special Weather Statements in South Carolina, 2017 Every special weather statement in 2017

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.