Alert archive / Oklahoma / Flash Flood Warnings in 2001

Flash Flood Warning 9, NWS Norman, OK

June 30, 2001Pottawatomie County, Seminole County, Oklahoma

NWS Norman, OK issued this flash flood warning at Jun 30, 2001, 2:43 AM CDT for Pottawatomie County, Seminole County, Oklahoma. It was in force for 4 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties.

The facts

Issued: Jun 30, 2001, 2:43 AM CDT (07:43 UTC)
Expired: Jun 30, 2001, 6:45 AM CDT
In force: 4 hr
Issued by: NWS Norman, OK
Area: Whole counties; the outline is the Mesonet’s reconstruction

Counties Pottawatomie County, OK, Seminole County, OK

The radar

The Norman radar (KTLX), 46 km from the middle of the area, began a volume at 07:42 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

Norman, OK (KOUN), launched 00:00Z, 7.7 hours before the alert went out and 54 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: 1853 J/kg
Mixed-layer CIN: -79 J/kg
Mixed-layer LCL: 1446 m above ground
0-6 km bulk shear: 43 kt
0-1 km storm-relative helicity: 65 m²/s²
0-3 km storm-relative helicity: 227 m²/s²
Significant tornado parameter: 0.6
Supercell composite: 7.9

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WGUS54 KOUN 300746
FFWOKC
OKC125-133-301145-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE NORMAN OK
243 AM CDT SAT JUN 30 2001

THE NATIONAL WEATHER SERVICE IN NORMAN HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  POTTAWATOMIE COUNTY IN CENTRAL OKLAHOMA
  SEMINOLE COUNTY IN EAST CENTRAL OKLAHOMA

* UNTIL 645 AM CDT

* AT 243 AM CDT...DOPPLER RADAR INDICATED RAINFALL AMOUNTS IN EXCESS 
OF 3 INCHES OVER NORTHWEST SEMINOLE COUNTY AND PORTIONS EASTERN 
POTTAWATOMIE COUNTY SINCE MIDNIGHT. ADDITIONAL HEAVY RAIN WILL OCCUR 
AS THUNDERSTORMS TRACK SOUTH ACROSS THE AREA FROM LINCOLN COUNTY.  

EXCESSIVE RUNOFF FROM THESE STORMS WILL CAUSE FLASH FLOODING OF SMALL
CREEKS AND STREAMS...COUNTRY ROADS...NORMALLY DRY WASHES...AND FARM
LAND ALONG THE BANKS OF CREEKS AND STREAMS.

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODS. IF FLASH FLOODING IS OBSERVED ACT QUICKLY. MOVXE TO
HIGHER GROUND TO ESCAPE FLOOD WATERS. DO NOT DRIVE VEHICLES INTO
AREAS WHERE WATER COVERS THE ROADWAY.

LAT...LON 3498 9698 3491 9658 3547 9653 3546 9700

ANDRA

The office that day

Everything else NWS Norman, OK issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 30, 12:45 AM CDT	Severe Thunderstorm Warning	OUN	Seminole	45 min
Jun 30, 12:53 AM CDT	Severe Thunderstorm Warning	OUN	Lincoln	37 min
Jun 30, 1:23 AM CDT	Severe Thunderstorm Warning	OUN	Payne	52 min
Jun 30, 1:27 AM CDT	Severe Thunderstorm Warning	OUN	Pottawatomie, Seminole	48 min
Jun 30, 1:55 AM CDT	Severe Thunderstorm Warning	OUN	Lincoln	50 min
Jun 30, 2:13 AM CDT	Severe Thunderstorm Warning	OUN	Pottawatomie, Seminole	62 min
Jun 30, 2:18 AM CDT	Severe Thunderstorm Warning	OUN	Garfield	57 min
Jun 30, 2:38 AM CDT	Severe Thunderstorm Warning	OUN	Lincoln	37 min
Jun 30, 2:40 AM CDT	Severe Thunderstorm Warning	OUN	Atoka	50 min
Jun 30, 3:14 AM CDT	Severe Thunderstorm Warning	OUN	Lincoln, Pottawatomie	46 min
Jun 30, 3:58 AM CDT	Severe Thunderstorm Warning	OUN	Garvin, McClain, Pottawatomie	47 min
Jun 30, 4:43 AM CDT	Severe Thunderstorm Warning	OUN	Garvin, Murray	47 min

Nearby

Flash Flood Warnings in Oklahoma, 2001 Every flash flood warning in 2001

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.