Alert archive / Oklahoma / Flash Flood Warnings in 2021

Flash Flood Warning 48, NWS Norman, OK

July 10, 2021Oklahoma County, Oklahoma

NWS Norman, OK issued this flash flood warning at Jul 10, 2021, 9:43 PM CDT for Oklahoma County, Oklahoma. It was in force for 2 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: Jul 10, 2021, 9:43 PM CDT (02:43 UTC)
Expired: Jul 11, 2021, 12:09 AM CDT
In force: 2 hr
Issued by: NWS Norman, OK
Area: Storm-based polygon
Flood severity: None

County Oklahoma County, OK

The radar

The Norman radar (KTLX), 20 km from the middle of the area, began a volume at 02:42 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.

What was reported inside it

Time	Report	Where	Remark
Jul 10, 9:45 PM CDT	FLASH FLOOD	1 Sw Valley Brook, OK	ACCESS ROADS ALMOST IMPASSABLE AT I240/I35 JUNCTION. UNDERPASSES QUICKLY FILLING WITH WATER.

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

The nearest sounding before it

Norman, OK (KOUN), launched 00:00Z, 2.7 hours before the alert went out and 31 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: 2495 J/kg
Mixed-layer CIN: -69 J/kg
Mixed-layer LCL: 1225 m above ground
0-6 km bulk shear: 41 kt
0-1 km storm-relative helicity: 156 m²/s²
0-3 km storm-relative helicity: 185 m²/s²
Significant tornado parameter: 1.4
Supercell composite: 14.8

Open this sounding in Storm Lab

The text

As transmitted.

943 
WGUS54 KOUN 110243
FFWOUN
OKC109-110545-
/O.NEW.KOUN.FF.W.0048.210711T0243Z-210711T0545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Norman OK
943 PM CDT Sat Jul 10 2021

The National Weather Service in Norman has issued a

* Flash Flood Warning for...
  Southern Oklahoma County in central Oklahoma...

* Until 1245 AM CDT.

* At 943 PM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Up to 1 inch of rain has 
  fallen. Additional rainfall amounts of 2 to 3 inches are possible 
  in the warned area. Flash flooding is ongoing or expected to begin 
  shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar.

  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...
  Oklahoma City, Midwest City, Del City, Bethany, Choctaw, Warr 
  Acres, The Village, Harrah, Spencer, Nichols Hills, Jones, Nicoma 
  Park, Valley Brook, Tinker Air Force Base, Newalla, Forest Park, 
  Woodlawn Park, Lake Aluma, Smith Village and The Capitol.

This includes the following highways...
	Interstate 35 between mile markers 121 and 132.
	Interstate 44 between mile markers 115 and 128.
	Interstate 40 between mile markers 142 and 173.
	Interstate 240 between mile markers 1 and 16.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3547 9714 3538 9714 3538 9767 3561 9767
      3561 9750 3553 9749 3553 9714

FLASH FLOOD...RADAR INDICATED

$$

JP

2 follow-up statements

664 
WGUS74 KOUN 110357
FFSOUN

Flash Flood Statement
National Weather Service Norman OK
1057 PM CDT Sat Jul 10 2021

OKC109-110545-
/O.CON.KOUN.FF.W.0048.000000T0000Z-210711T0545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Oklahoma OK-
1057 PM CDT Sat Jul 10 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1245 AM CDT SUNDAY 
FOR SOUTHERN OKLAHOMA COUNTY...

At 1057 PM CDT, trained weather spotters reported I-240/I235 
Junction almost impassable, with the underpass quickly filling with 
water.  Thunderstorms had produced heavy rain across the warned 
area. Between 1 and 2 inches of rain have fallen. Flash flooding is 
ongoing.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Trained spotters reported.

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...
  Oklahoma City, Midwest City, Del City, Bethany, Choctaw, Warr 
  Acres, The Village, Harrah, Spencer, Nichols Hills, Jones, Nicoma 
  Park, Valley Brook, Tinker Air Force Base, Newalla, Forest Park, 
  Woodlawn Park, Lake Aluma, Smith Village and The Capitol.

This includes the following highways...
	Interstate 35 between mile markers 121 and 132.
	Interstate 44 between mile markers 115 and 129.
	Interstate 40 between mile markers 142 and 173.
	Interstate 240 between mile markers 1 and 16.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3547 9714 3538 9714 3538 9767 3561 9767
      3561 9750 3553 9749 3553 9714

FLASH FLOOD...OBSERVED

$$

JP

877 
WGUS74 KOUN 110509
FFSOUN

Flash Flood Statement
National Weather Service Norman OK
1209 AM CDT Sun Jul 11 2021

OKC109-110519-
/O.CAN.KOUN.FF.W.0048.000000T0000Z-210711T0545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Oklahoma OK-
1209 AM CDT Sun Jul 11 2021

...FLASH FLOOD WARNING IS CANCELLED FOR SOUTHERN OKLAHOMA COUNTY...

The heavy rain has ended. Flooding is no longer expected to pose a 
threat. Please continue to heed remaining road closures.

LAT...LON 3547 9714 3538 9714 3538 9767 3561 9767
      3561 9750 3553 9749 3553 9714

$$

JP

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 10, 7:12 PM CDT	Severe Thunderstorm Warning	OUN	Logan, Payne	18 min
Jul 10, 7:23 PM CDT	Severe Thunderstorm Warning	OUN	Lincoln, Logan, Payne	52 min
Jul 10, 7:47 PM CDT	Special Weather Statement	OUN	Kingfisher	28 min
Jul 10, 7:52 PM CDT	Areal Flood Advisory	OUN	Lincoln, Logan, Payne	3 hr
Jul 10, 7:58 PM CDT	Severe Thunderstorm Warning	OUN	Kingfisher, Lincoln, Logan, Oklahoma, Payne	47 min
Jul 10, 8:02 PM CDT	Special Weather Statement	OUN	Blaine	43 min
Jul 10, 8:14 PM CDT	Severe Thunderstorm Warning	OUN	Blaine, Canadian, Kingfisher	61 min
Jul 10, 8:25 PM CDT	Severe Thunderstorm Warning	OUN	Lincoln, Logan, Oklahoma, Pottawatomie	50 min
Jul 10, 8:27 PM CDT	Special Weather Statement	OUN	Beckham	48 min
Jul 10, 8:36 PM CDT	Areal Flood Advisory	OUN	Lincoln, Logan, Oklahoma	3 hr
Jul 10, 8:49 PM CDT	Flash Flood Warning	OUN	Lincoln, Payne	101 min
Jul 10, 8:53 PM CDT	Areal Flood Advisory	OUN	Lincoln, Oklahoma, Pottawatomie	3 hr
Jul 10, 8:59 PM CDT	Severe Thunderstorm Warning	OUN	Blaine, Caddo, Canadian, Custer, Grady, Washita	61 min
Jul 10, 9:02 PM CDT	Flash Flood Warning	OUN	Oklahoma	3 hr
Jul 10, 9:11 PM CDT	Severe Thunderstorm Warning	OUN	Cleveland, Lincoln, McClain, Oklahoma, Pottawatomie	49 min
Jul 10, 9:20 PM CDT	Special Weather Statement	OUN	Okfuskee	40 min
Jul 10, 9:31 PM CDT	Areal Flood Advisory	OUN	Cleveland, McClain, Oklahoma, Pottawatomie, Seminole	3 hr
Jul 10, 9:35 PM CDT	Severe Thunderstorm Warning	OUN	Caddo, Cleveland, Grady, McClain	25 min
Jul 10, 9:43 PM CDT	Areal Flood Advisory	OUN	Blaine, Caddo, Canadian, Grady	3 hr
Jul 10, 10:00 PM CDT	Severe Thunderstorm Warning	OUN	Caddo, Grady, Kiowa, Washita	45 min
Jul 10, 10:02 PM CDT	Special Weather Statement	OUN	Cleveland, McClain, Pottawatomie	43 min
Jul 10, 10:19 PM CDT	Areal Flood Advisory	OUN	Seminole	3 hr
Jul 10, 10:23 PM CDT	Areal Flood Advisory	OUN	Caddo, Grady	3 hr
Jul 10, 10:37 PM CDT	Severe Thunderstorm Warning	OUN	Caddo, Comanche, Grady, Kiowa, Washita	38 min
Jul 10, 10:39 PM CDT	Severe Thunderstorm Warning	OUN	Hughes, McClain, Pontotoc, Pottawatomie, Seminole	51 min
Jul 10, 10:45 PM CDT	Special Weather Statement	OUN	Grady	30 min
Jul 10, 10:48 PM CDT	Severe Thunderstorm Warning	OUN	Garvin, Grady	42 min
Jul 10, 10:54 PM CDT	Special Weather Statement	OUN	Grady	36 min
Jul 10, 11:11 PM CDT	Areal Flood Advisory	OUN	Caddo, Comanche, Cotton, Grady, Stephens	3 hr
Jul 10, 11:12 PM CDT	Severe Thunderstorm Warning	OUN	Caddo, Comanche, Grady, Kiowa, Stephens	63 min
Jul 10, 11:15 PM CDT	Severe Thunderstorm Warning	OUN	Coal, Hughes, Johnston, Pontotoc	60 min
Jul 10, 11:31 PM CDT	Flash Flood Warning	OUN	Comanche	3 hr
Jul 10, 11:35 PM CDT	Special Weather Statement	OUN	Stephens	25 min
Jul 10, 11:38 PM CDT	Severe Thunderstorm Warning	OUN	Comanche, Cotton, Jefferson, Stephens	52 min
Jul 10, 11:44 PM CDT	Severe Thunderstorm Warning	OUN	Carter, Garvin, Murray, Stephens	46 min
Jul 10, 11:59 PM CDT	Severe Thunderstorm Warning	OUN	Comanche, Cotton, Kiowa, Tillman	46 min
Jul 11, 12:02 AM CDT	Severe Thunderstorm Warning	OUN	Atoka, Bryan, Coal	58 min
Jul 11, 12:23 AM CDT	Areal Flood Advisory	OUN	Comanche, Cotton, Jefferson, Stephens, Tillman	3 hr
Jul 11, 12:23 AM CDT	Severe Thunderstorm Warning	OUN	Carter, Comanche, Cotton, Jefferson, Love, Marshall and 1 more	67 min
Jul 11, 12:32 AM CDT	Areal Flood Advisory	OUN	Coal, Hughes, Pontotoc	3 hr
Jul 11, 12:43 AM CDT	Severe Thunderstorm Warning	OUN	Carter, Johnston, Love, Marshall	47 min
Jul 11, 12:46 AM CDT	Special Weather Statement	OUN	Jackson, Tillman	44 min
Jul 11, 12:48 AM CDT	Severe Thunderstorm Warning	OUN	Jackson, Kiowa, Tillman	42 min
Jul 11, 12:54 AM CDT	Areal Flood Advisory	OUN	Carter, Garvin, Jefferson, Murray, Stephens	3 hr
Jul 11, 1:05 AM CDT	Areal Flood Advisory	OUN	Atoka, Coal, Johnston, Pontotoc	3 hr
Jul 11, 1:24 AM CDT	Areal Flood Advisory	OUN	Comanche, Jackson, Kiowa, Tillman	3 hr
Jul 11, 1:24 AM CDT	Severe Thunderstorm Warning	OUN	Tillman	51 min
Jul 11, 1:33 AM CDT	Special Weather Statement	OUN	Bryan	42 min
Jul 11, 1:36 AM CDT	Areal Flood Advisory	OUN	Cotton, Jefferson, Tillman	3 hr
Jul 11, 2:23 AM CDT	Areal Flood Warning	OUN	Comanche	3 hr
Jul 11, 12:15 PM CDT	River Flood Advisory	OUN	Comanche, Cotton	34 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.