Alert archive / Virginia / Flash Flood Watches in 2014

Flash Flood Watch 4, NWS Blacksburg, VA

August 22, 20148 counties in Virginia; Mercer County, Monroe County, Summers County, West Virginia

NWS Blacksburg, VA issued this flash flood watch at Aug 22, 2014, 4:36 AM EDT for 8 counties in Virginia; Mercer County, Monroe County, Summers County, West Virginia. It was in force for 19 hr.

The area

The counties it named.

The facts

Issued: Aug 22, 2014, 4:36 AM EDT (08:36 UTC)
Expired: Aug 22, 2014, 11:50 PM EDT
In force: 19 hr
Issued by: NWS Blacksburg, VA
Flood severity: None

Counties Bland County, VA, City of Radford, VA, Giles County, VA, Montgomery County, VA, Pulaski County, VA, Smyth County, VA, Tazewell County, VA, Wythe County, VA, Mercer County, WV, Monroe County, WV, Summers County, WV

The radar

The Roanoke radar (KFCX), 62 km from the middle of the area, began a volume at 08:36 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

Cncnati-Daytn, OH (KILN), launched 00:00Z, 8.6 hours before the alert went out and 352 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: 536 J/kg
Mixed-layer CIN: -57 J/kg
Mixed-layer LCL: 772 m above ground
0-6 km bulk shear: 40 kt
0-1 km storm-relative helicity: 156 m²/s²
0-3 km storm-relative helicity: 234 m²/s²
Significant tornado parameter: 0.4
Supercell composite: 3.9

Open this sounding in Storm Lab

What forecasters said that day

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

NWS Blacksburg, VA wrote its last area forecast discussion before this flash flood watch went out at Aug 21, 7:48 PM EDT, 8 hours 48 minutes earlier.

Area forecast discussion, Aug 21, 7:48 PM EDT, 8 hours 48 minutes before

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Hazardous weather outlook, Aug 21, 5:24 PM EDT, 11 hours 12 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BLACKSBURG VA
524 PM EDT THU AUG 21 2014

VAZ007-009>014-018>020-WVZ042>045-222130-
TAZEWELL-SMYTH-BLAND-GILES-WYTHE-PULASKI-MONTGOMERY-CRAIG-
ALLEGHANY VA-BATH-MERCER-SUMMERS-MONROE-GREENBRIER-
524 PM EDT THU AUG 21 2014

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHWEST VIRGINIA...WEST
CENTRAL VIRGINIA AND SOUTHEAST WEST VIRGINIA.

.DAY ONE...TONIGHT.

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS INTO TONIGHT AS
COMPLEXES OF STORMS DROP SOUTHEAST FROM KENTUCKY. THE PRIMARY
THREAT WOULD BE DAMAGING WINDS WITH ISOLATED LARGE HAIL POSSIBLE.
IN ADDITION...HEAVY RAINS FROM THESE STORMS COULD PRODUCE
LOCALIZED FLOODING.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.

PERIODIC ROUNDS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED ACROSS
THE REGION THROUGH THIS UPCOMING WEEKEND...BRINGING A RISK OF
STRONG THUNDERSTORMS AND EXCESSIVE RAINFALL.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

NCZ001>006-018>020-VAZ015>017-022>024-032>035-043>047-058-059-222130-
ASHE-ALLEGHANY NC-SURRY-STOKES-ROCKINGHAM-CASWELL-WATAUGA-WILKES-
YADKIN-GRAYSON-CARROLL-FLOYD-ROANOKE-BOTETOURT-ROCKBRIDGE-PATRICK-
FRANKLIN-BEDFORD-AMHERST-HENRY-PITTSYLVANIA-CAMPBELL-APPOMATTOX-
BUCKINGHAM-HALIFAX-CHARLOTTE-
524 PM EDT THU AUG 21 2014

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH CENTRAL NORTH
CAROLINA...NORTHWEST NORTH CAROLINA...CENTRAL VIRGINIA...SOUTH
CENTRAL VIRGINIA...SOUTHWEST VIRGINIA AND WEST CENTRAL VIRGINIA.

.DAY ONE...TONIGHT.

BANDS OR CLUSTERS OF STRONG TO ISOLATED SEVERE THUNDERSTORMS WILL
BE POSSIBLE INTO TONIGHT. SOME OF THESE COULD PRODUCE DAMAGING
WINDS ALONG WITH WITH ISOLATED LARGE HAIL.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.

PERIODIC ROUNDS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED ACROSS
THE REGION THROUGH THIS UPCOMING WEEKEND...BRINGING A RISK OF
STRONG THUNDERSTORMS AND EXCESSIVE RAINFALL.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

The office that day

Everything else NWS Blacksburg, VA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 21, 8:27 PM EDT	Special Weather Statement	RNK	Halifax	48 min
Aug 22, 3:45 PM EDT	Special Weather Statement	RNK	City of Martinsville	60 min
Aug 22, 4:16 PM EDT	Special Weather Statement	RNK	Bland	59 min
Aug 22, 4:48 PM EDT	Special Weather Statement	RNK	Tazewell	27 min
Aug 22, 5:13 PM EDT	Special Weather Statement	RNK	Bland, Wythe	47 min
Aug 22, 5:57 PM EDT	Special Weather Statement	RNK	Carroll, Grayson, Wythe, City of Galax	48 min
Aug 22, 6:44 PM EDT	Special Weather Statement	RNK	Grayson	31 min
Aug 22, 7:36 PM EDT	Special Weather Statement	RNK	Ashe	24 min
Aug 22, 7:54 PM EDT	Special Weather Statement	RNK	Watauga	36 min
Aug 22, 3:41 PM EDT	Special Weather Statement	RNK	Mercer	49 min

Nearby

Flash Flood Watches in Virginia, 2014 Flash Flood Watches in West Virginia, 2014 Every flash flood watch in 2014

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.