Alert archive / Oklahoma / Flash Flood Warnings in 2021

Flash Flood Warning 58, NWS Norman, OK

August 19, 2021Comanche County, Oklahoma

NWS Norman, OK issued this flash flood warning at Aug 19, 2021, 8:14 AM CDT for Comanche County, Oklahoma. It was in force for 3 hr. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Aug 19, 2021, 8:14 AM CDT (13:14 UTC)
Expired: Aug 19, 2021, 10:45 AM CDT
In force: 3 hr
Issued by: NWS Norman, OK
Area: Storm-based polygon
Flood severity: None

County Comanche County, OK

The radar

The Altus AFB radar (KFDR), 57 km from the middle of the area, began a volume at 13:15 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.

What was reported inside it

Time	Report	Where	Remark
Aug 19, 9:09 AM CDT	HEAVY RAIN 2.42	Lawton, OK	UNOFFICAL MEASUREMENTS OF 3.5 TO 4.5 INCHES AROUND SE LEE BLVD AND SE 45TH ST.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Fort Worth, TX (KFWD), launched 12:00Z, 1.2 hours before the alert went out and 217 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: 1118 J/kg
Mixed-layer CIN: -51 J/kg
Mixed-layer LCL: 675 m above ground
0-6 km bulk shear: 14 kt
0-1 km storm-relative helicity: 50 m²/s²
0-3 km storm-relative helicity: 109 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

438 
WGUS54 KOUN 191314
FFWOUN
OKC031-191545-
/O.NEW.KOUN.FF.W.0058.210819T1314Z-210819T1545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Norman OK
814 AM CDT Thu Aug 19 2021

The National Weather Service in Norman has issued a

* Flash Flood Warning for...
  Southeastern Comanche County in southwestern Oklahoma...

* Until 1045 AM CDT.

* At 814 AM CDT, Doppler radar and automated rain gauges indicated 
  thunderstorms producing heavy rain across the warned area. Between 
  2 and 4 inches of rain have fallen. Additional rainfall amounts of 
  1 to 2 inches are possible in the warned area. Flash flooding is 
  ongoing or expected to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar and automated gauges.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  Lawton, Geronimo and southeastern Fort Sill.

This includes the following highways...
	Interstate 44 between mile markers 27 and 39.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3445 9856 3457 9846 3461 9842 3467 9827
      3467 9815 3454 9831 3445 9842

FLASH FLOOD...RADAR AND GAUGE INDICATED

$$

Ware

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 19, 7:38 AM CDT	Areal Flood Advisory	OUN	Comanche	36 min
Aug 19, 3:27 PM CDT	Special Weather Statement	OUN	Beckham	33 min
Aug 19, 3:29 PM CDT	Special Weather Statement	OUN	Harmon	31 min
Aug 19, 4:10 PM CDT	Special Weather Statement	OUN	Beckham	35 min
Aug 19, 4:59 PM CDT	Severe Thunderstorm Warning	OUN	Greer, Harmon	31 min
Aug 19, 5:14 PM CDT	Severe Thunderstorm Warning Considerable damage threat	OUN	Greer, Harmon, Jackson	31 min
Aug 19, 5:28 PM CDT	Severe Thunderstorm Warning Considerable damage threat	OUN	Greer, Harmon, Jackson	47 min
Aug 19, 6:02 PM CDT	Severe Thunderstorm Warning Considerable damage threat	OUN	Comanche, Jackson, Kiowa, Tillman	28 min
Aug 19, 6:26 PM CDT	Severe Thunderstorm Warning Considerable damage threat	OUN	Jackson, Tillman	34 min

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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.