Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 488, NWS Norman, OK
NWS Norman, OK issued this severe thunderstorm warning at Sep 17, 2021, 7:48 PM CDT for Ellis County, Harper County, Oklahoma. It was in force for 42 min. No storm report in the archive falls inside the area while it was in force.
The area
The outline as issued.
The facts
- Issued
- Sep 17, 2021, 7:48 PM CDT (00:48 UTC)
- Expired
- Sep 17, 2021, 8:30 PM CDT
- In force
- 42 min
- Issued by
- NWS Norman, OK
- Area
- Storm-based polygon
- Damage threat
- Considerable
- Hail
- 1.0 in
- Wind
- 70.0 mph
Counties Ellis County, OK, Harper County, OK
The nearest sounding before it
Dodge City, (KDDC), launched 00:00Z, 0.8 hours before the alert went out and 124 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.
- Mixed-layer CAPE
- 1092 J/kg
- Mixed-layer CIN
- -21 J/kg
- Mixed-layer LCL
- 1639 m above ground
- 0-6 km bulk shear
- 30 kt
- 0-1 km storm-relative helicity
- 25 m²/s²
- 0-3 km storm-relative helicity
- 142 m²/s²
- Significant tornado parameter
- 0.1
- Supercell composite
- 1.4
The text
As transmitted.
624
WUUS54 KOUN 180048
SVROUN
OKC045-059-180130-
/O.NEW.KOUN.SV.W.0488.210918T0048Z-210918T0130Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Norman OK
748 PM CDT Fri Sep 17 2021
The National Weather Service in Norman has issued a
* Severe Thunderstorm Warning for...
North central Ellis County in northwestern Oklahoma...
Southwestern Harper County in northwestern Oklahoma...
* Until 830 PM CDT.
* At 748 PM CDT, a severe thunderstorm was located near May, moving
southeast at 15 mph.
HAZARD...70 mph wind gusts and quarter size hail.
SOURCE...Radar indicated.
IMPACT...Hail damage to vehicles is expected. Expect considerable
tree damage. Wind damage is also likely to mobile homes,
roofs, and outbuildings.
* Locations impacted include...
Laverne and May.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 3669 9996 3677 9978 3665 9953 3648 9986
TIME...MOT...LOC 0048Z 315DEG 14KT 3665 9980
THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...70 MPH
$$
JP1 follow-up statement
122
WWUS54 KOUN 180126
SVSOUN
Severe Weather Statement
National Weather Service Norman OK
826 PM CDT Fri Sep 17 2021
OKC045-059-180136-
/O.EXP.KOUN.SV.W.0488.000000T0000Z-210918T0130Z/
Ellis OK-Harper OK-
826 PM CDT Fri Sep 17 2021
...THE SEVERE THUNDERSTORM WARNING FOR NORTH CENTRAL ELLIS AND
SOUTHWESTERN HARPER COUNTIES WILL EXPIRE AT 830 PM CDT...
The storm which prompted the warning has moved out of the area.
Therefore, the warning will be allowed to expire.
LAT...LON 3669 9996 3677 9978 3665 9953 3648 9986
TIME...MOT...LOC 0126Z 315DEG 14KT 3655 9967
$$
JPThe office that day
Everything else NWS Norman, OK issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 17, 7:28 PM CDT | Severe Thunderstorm Warning | OUN | Harper | 47 min |
| Sep 17, 7:34 PM CDT | Areal Flood Advisory | OUN | Harper | 3 hr |
| Sep 17, 8:04 PM CDT | Severe Thunderstorm Warning | OUN | Ellis, Harper, Woodward | 41 min |
| Sep 17, 8:46 PM CDT | Special Weather Statement | OUN | Ellis | 29 min |
| Sep 17, 8:48 PM CDT | Special Weather Statement | OUN | Ellis | 27 min |
| Sep 17, 9:21 PM CDT | Special Weather Statement | OUN | Ellis | 24 min |
| Sep 17, 9:54 PM CDT | Special Weather Statement | OUN | Roger Mills | 36 min |
Nearby
Severe Thunderstorm Warnings in Oklahoma, 2021Every severe thunderstorm 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.