Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 16, NWS Norman, OK

March 13, 2021Harmon County, Jackson County, Oklahoma; Hardeman County, Texas

NWS Norman, OK issued this severe thunderstorm warning at Mar 13, 2021, 8:02 PM CST for Harmon County, Jackson County, Oklahoma; Hardeman County, Texas. It was in force for 28 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: Mar 13, 2021, 8:02 PM CST (02:02 UTC)
Expired: Mar 13, 2021, 8:30 PM CST
In force: 28 min
Issued by: NWS Norman, OK
Area: Storm-based polygon
Tornado: Possible
Hail: 1.5 in
Wind: 70.0 mph

Counties Harmon County, OK, Jackson County, OK, Hardeman County, TX

The radar

The Altus AFB radar (KFDR), 78 km from the middle of the area, began a volume at 02:03 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, 2.0 hours before the alert went out and 236 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: 217 J/kg
Mixed-layer CIN: -129 J/kg
Mixed-layer LCL: 862 m above ground
0-6 km bulk shear: 55 kt
0-1 km storm-relative helicity: 212 m²/s²
0-3 km storm-relative helicity: 248 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 2.3

Open this sounding in Storm Lab

The text

As transmitted.

878 
WUUS54 KOUN 140202
SVROUN
OKC057-065-TXC197-140230-
/O.NEW.KOUN.SV.W.0016.210314T0202Z-210314T0230Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Norman OK
802 PM CST Sat Mar 13 2021

The National Weather Service in Norman has issued a

* Severe Thunderstorm Warning for...
  West central Jackson County in southwestern Oklahoma...
  Southeastern Harmon County in southwestern Oklahoma...
  Northwestern Hardeman County in northern Texas...

* Until 830 PM CST.

* At 802 PM CST, a severe thunderstorm was located 7 miles north of
  Goodlett, moving northeast at 35 mph.

  HAZARD...70 mph wind gusts and ping pong ball size hail.

  SOURCE...Radar indicated.

  IMPACT...People and animals outdoors will be injured. Expect hail 
           damage to roofs, siding, windows, and vehicles. Expect 
           considerable tree damage. Wind damage is also likely to 
           mobile homes, roofs, and outbuildings.

* This severe thunderstorm will remain over mainly rural areas of
  west central Jackson, southeastern Harmon and northwestern Hardeman
  Counties.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain alert for a possible tornado! Tornadoes can develop quickly
from severe thunderstorms. If you spot a tornado go at once into the
basement or small central room in a sturdy structure.

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3433 9998 3448 9996 3460 9978 3457 9962
      3452 9961
TIME...MOT...LOC 0202Z 240DEG 32KT 3444 9988 

TORNADO...POSSIBLE
HAIL...1.50IN
WIND...70MPH
 
$$

Mahale

1 follow-up statement

599 
WWUS54 KOUN 140229
SVSOUN

Severe Weather Statement
National Weather Service Norman OK
829 PM CST Sat Mar 13 2021

OKC057-065-TXC197-140239-
/O.EXP.KOUN.SV.W.0016.000000T0000Z-210314T0230Z/
Jackson OK-Harmon OK-Hardeman TX-
829 PM CST Sat Mar 13 2021

...THE SEVERE THUNDERSTORM WARNING FOR WEST CENTRAL JACKSON...
SOUTHEASTERN HARMON AND NORTHWESTERN HARDEMAN COUNTIES WILL EXPIRE AT
830 PM CST...
        
The storm which prompted the warning has weakened below severe
limits, and has exited the warned area. Therefore, the warning will
be allowed to expire.

LAT...LON 3433 9998 3448 9996 3460 9978 3457 9962
      3452 9961
TIME...MOT...LOC 0229Z 240DEG 32KT 3455 9964 

$$

Mahale

The office that day

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

Issued	Product	Office	Counties	Lasted
Mar 13, 7:57 PM CST	Tornado Warning	OUN	Jackson	18 min
Mar 13, 8:05 PM CST	Tornado Warning	OUN	Harmon, Jackson	25 min
Mar 13, 8:31 PM CST	Special Weather Statement	OUN	Harmon	29 min
Mar 13, 8:33 PM CST	Severe Thunderstorm Warning	OUN	Greer, Harmon, Jackson	42 min
Mar 13, 9:11 PM CST	Severe Thunderstorm Warning	OUN	Ellis	49 min
Mar 13, 9:16 PM CST	Special Weather Statement	OUN	Greer	29 min
Mar 13, 9:46 PM CST	Special Weather Statement	OUN	Beckham	29 min
Mar 13, 9:52 PM CST	Special Weather Statement	OUN	Harper	23 min
Mar 13, 10:14 PM CST	Special Weather Statement	OUN	Harper	46 min
Mar 13, 10:15 PM CST	Special Weather Statement	OUN	Roger Mills	45 min
Mar 13, 7:17 PM CST	Severe Thunderstorm Warning	OUN	Foard, Hardeman	43 min
Mar 13, 7:32 PM CST	Tornado Warning	OUN	Foard, Hardeman	28 min
Mar 13, 8:42 PM CST	Special Weather Statement	OUN	Knox	48 min
Mar 13, 9:26 PM CST	Special Weather Statement	OUN	Baylor, Knox	49 min
Mar 13, 10:52 PM CST	Special Weather Statement	OUN	Archer	38 min

Nearby

Severe Thunderstorm Warnings in Oklahoma, 2021 Severe Thunderstorm Warnings in Texas, 2021 Every 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; radar from the NEXRAD Level II archive.