Alert archive / Oklahoma / Flash Flood Warnings in 2021

Flash Flood Warning 36, NWS Norman, OK

June 28, 2021Caddo County, Grady County, Oklahoma

NWS Norman, OK issued this flash flood warning at Jun 28, 2021, 2:32 PM CDT for Caddo County, Grady County, Oklahoma. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Jun 28, 2021, 2:32 PM CDT (19:32 UTC)
Expired: Jun 28, 2021, 5:45 PM CDT
In force: 3 hr
Issued by: NWS Norman, OK
Area: Storm-based polygon
Flood severity: None

Counties Caddo County, OK, Grady County, OK

The radar

The Norman radar (KTLX), 73 km from the middle of the area, began a volume at 19:31 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

Fort Worth, TX (KFWD), launched 12:00Z, 7.5 hours before the alert went out and 279 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: 218 J/kg
Mixed-layer CIN: -45 J/kg
Mixed-layer LCL: 802 m above ground
0-6 km bulk shear: 13 kt
0-1 km storm-relative helicity: 7 m²/s²
0-3 km storm-relative helicity: 11 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

835 
WGUS54 KOUN 281932
FFWOUN
OKC015-051-282245-
/O.NEW.KOUN.FF.W.0036.210628T1932Z-210628T2245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Norman OK
232 PM CDT Mon Jun 28 2021

The National Weather Service in Norman has issued a

* Flash Flood Warning for...
  Northwestern Grady County in central Oklahoma...
  East Central Caddo County in southwestern Oklahoma...

* Until 545 PM CDT.

* At 232 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 3 inches of rain 
  have fallen. Flash flooding is ongoing or expected to begin 
  shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Doppler radar.

  IMPACT...Flooding of small creeks and streams, urban areas,
           highways, streets and underpasses as well as other
           drainage and low lying areas.

* Some locations that will experience flash flooding include...
  Verden, Lake Chickasha and Cogar.

Additional rainfall amounts up to 2 inches are possible in the 
warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Excessive runoff from heavy rainfall will cause flooding of small 
creeks and streams, country roads, farmland, and other low lying 
spots.


&&

LAT...LON 3536 9803 3511 9801 3506 9818 3536 9815

FLASH FLOOD...RADAR INDICATED

$$

11

1 follow-up statement

583 
WGUS74 KOUN 282052
FFSOUN

Flash Flood Statement
National Weather Service Norman OK
352 PM CDT Mon Jun 28 2021

OKC015-051-282245-
/O.CON.KOUN.FF.W.0036.000000T0000Z-210628T2245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Caddo OK-Grady OK-
352 PM CDT Mon Jun 28 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 545 PM CDT THIS 
AFTERNOON FOR NORTHWESTERN GRADY AND EAST CENTRAL CADDO COUNTIES...

At 352 PM CDT, Doppler radar indicated that earlier thunderstorms 
produced heavy rain across the warned area. Up to 3 inches of rain 
have fallen. Flash flooding is ongoing or expected to begin shortly.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Doppler radar.

IMPACT...Flooding of small creeks and streams, urban areas,
         highways, streets and underpasses as well as other
         drainage and low lying areas.

Some locations that will experience flash flooding include...
  Verden, Lake Chickasha and Cogar.

Heavy rainfall has ended, but runoff will result in a continued 
flash flood threat.  Additional rainfall amounts up to 1 inch are 
possible in the warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Excessive runoff from heavy rainfall will cause flooding of small 
creeks and streams, country roads, farmland, and other low lying 
spots.

&&

LAT...LON 3536 9803 3511 9801 3506 9818 3536 9815

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...0.5-1 INCH IN 1 HOUR 

$$

TL

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 27, 7:02 PM CDT	Special Weather Statement	OUN	Hughes	43 min
Jun 27, 7:22 PM CDT	Areal Flood Advisory	OUN	Pontotoc	3 hr
Jun 27, 7:23 PM CDT	Areal Flood Advisory	OUN	Coal, Hughes	3 hr
Jun 27, 7:41 PM CDT	Special Weather Statement	OUN	Hughes	49 min
Jun 28, 3:58 AM CDT	River Flood Advisory	OUN	Lincoln, Oklahoma, Pottawatomie	6 hr
Jun 28, 3:58 AM CDT	River Flood Advisory	OUN	Cleveland, McClain	5 hr
Jun 28, 9:52 AM CDT	Flood Watch	OUN	Alfalfa, Beckham, Blaine, Caddo, Canadian, Cleveland and 23 more	35 hr
Jun 28, 11:36 AM CDT	Areal Flood Advisory	OUN	Garvin	4 hr
Jun 28, 1:11 PM CDT	Areal Flood Advisory	OUN	Jackson	4 hr
Jun 28, 1:12 PM CDT	Areal Flood Advisory	OUN	Garfield, Kingfisher	4 hr
Jun 28, 1:20 PM CDT	Special Weather Statement	OUN	Garfield	25 min
Jun 28, 2:08 PM CDT	Areal Flood Advisory	OUN	Garfield, Kingfisher, Logan	3 hr
Jun 28, 2:32 PM CDT	River Flood Advisory	OUN	Payne	6 hr
Jun 28, 2:35 PM CDT	Areal Flood Advisory	OUN	Oklahoma	115 min
Jun 28, 2:55 PM CDT	Areal Flood Advisory	OUN	Canadian, Kingfisher	4 hr
Jun 28, 3:01 PM CDT	Areal Flood Advisory	OUN	Garfield, Kay, Noble	3 hr
Jun 28, 3:24 PM CDT	Flash Flood Warning	OUN	Blaine, Caddo, Canadian, Kingfisher	3 hr
Jun 28, 5:05 PM CDT	Special Weather Statement	OUN	Lincoln	25 min
Jun 28, 5:11 PM CDT	Special Weather Statement	OUN	Hughes	19 min
Jun 28, 5:40 PM CDT	Areal Flood Advisory	OUN	Tillman	3 hr
Jun 28, 5:56 PM CDT	Special Weather Statement	OUN	McClain	34 min
Jun 28, 6:00 PM CDT	Special Weather Statement	OUN	Lincoln	30 min
Jun 28, 6:27 PM CDT	Areal Flood Advisory	OUN	Cleveland, Lincoln, Logan, McClain, Oklahoma	2 hr
Jun 28, 6:32 PM CDT	Flash Flood Warning	OUN	Blaine, Kingfisher	4 hr

Nearby

Flash Flood Warnings in Oklahoma, 2021 Every flash flood warning in 2021

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.