Alert archive / Texas / Tornado Warnings in 2021

Tornado Warning 17, NWS Norman, OK

April 28, 2021Clay County, Texas

NWS Norman, OK issued this tornado warning at Apr 28, 2021, 5:28 AM CDT for Clay County, Texas. It was in force for 17 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: Apr 28, 2021, 5:28 AM CDT (10:28 UTC)
Expired: Apr 28, 2021, 5:45 AM CDT
In force: 17 min
Issued by: NWS Norman, OK
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 0.75 in

County Clay County, TX

The radar

The Altus AFB radar (KFDR), 89 km from the middle of the area, began a volume at 10:29 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Apr 28, 3:01 AM CDT	Tornado Watch	SPC	7 hr

The nearest sounding before it

Fort Worth, TX (KFWD), launched 00:00Z, 10.5 hours before the alert went out and 146 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: 692 J/kg
Mixed-layer CIN: -275 J/kg
Mixed-layer LCL: 967 m above ground
0-6 km bulk shear: 61 kt
0-1 km storm-relative helicity: 197 m²/s²
0-3 km storm-relative helicity: 388 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.3

Open this sounding in Storm Lab

The text

As transmitted.

848 
WFUS54 KOUN 281028
TOROUN
TXC077-281045-
/O.NEW.KOUN.TO.W.0017.210428T1028Z-210428T1045Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Norman OK
528 AM CDT Wed Apr 28 2021

The National Weather Service in Norman has issued a

* Tornado Warning for...
  Northeastern Clay County in northern Texas...

* Until 545 AM CDT.
    
* At 528 AM CDT, a severe thunderstorm capable of producing a tornado
  was located near Henrietta, moving northeast at 50 mph.

  HAZARD...Tornado.

  SOURCE...Radar indicated rotation.

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely.

* Locations impacted include...
  Henrietta and Petrolia. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a storm shelter, safe room or an interior
room on the lowest floor of a sturdy building. Avoid windows. If you
are outdoors, in a mobile home, or in a vehicle, move to the closest
substantial shelter and protect yourself from flying debris.

Heavy rainfall may hide this tornado. Do not wait to see or hear the
tornado. TAKE COVER NOW!

&&

LAT...LON 3378 9828 3406 9825 3401 9809 3400 9808
      3399 9802 3377 9823
TIME...MOT...LOC 1028Z 204DEG 44KT 3380 9824 

TORNADO...RADAR INDICATED
HAIL...<.75IN

$$

11

2 follow-up statements

636 
WWUS54 KOUN 281039
SVSOUN

Severe Weather Statement
National Weather Service Norman OK
539 AM CDT Wed Apr 28 2021

TXC077-281045-
/O.CON.KOUN.TO.W.0017.000000T0000Z-210428T1045Z/
Clay TX-
539 AM CDT Wed Apr 28 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 545 AM CDT FOR
NORTHEASTERN CLAY COUNTY...
    
At 538 AM CDT, a severe thunderstorm capable of producing a tornado 
was located just north of Henrietta, moving northeast at 45 mph. The 
threat from any tornado has moved away from the city of Henrietta.

HAZARD...Tornado.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

This tornadic thunderstorm will remain over mainly rural areas of
northeastern Clay County.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a storm shelter, safe room, or an interior
room on the lowest floor of a sturdy building. Avoid windows. If you
are outdoors, in a mobile home, or in a vehicle, move to the closest
substantial shelter and protect yourself from flying debris.

Heavy rainfall may hide this tornado. Do not wait to see or hear the
tornado. TAKE COVER NOW!

&&

LAT...LON 3384 9824 3404 9821 3401 9809 3400 9808
      3399 9802 3383 9817
TIME...MOT...LOC 1038Z 208DEG 37KT 3387 9818 

TORNADO...RADAR INDICATED
HAIL...<.75IN

$$

11

007 
WWUS54 KOUN 281041
SVSOUN

Severe Weather Statement
National Weather Service Norman OK
541 AM CDT Wed Apr 28 2021

TXC077-281050-
/O.EXP.KOUN.TO.W.0017.000000T0000Z-210428T1045Z/
Clay TX-
541 AM CDT Wed Apr 28 2021

...THE TORNADO WARNING FOR NORTHEASTERN CLAY COUNTY WILL EXPIRE AT
545 AM CDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer appears capable of producing a tornado.
Therefore, the warning will be allowed to expire.  However gusty
winds and heavy rain are still possible with this thunderstorm.

LAT...LON 3384 9824 3404 9821 3401 9809 3400 9808
      3399 9802 3383 9817
TIME...MOT...LOC 1040Z 204DEG 44KT 3388 9817 

$$

11

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 27, 7:09 PM CDT	Severe Thunderstorm Warning	OUN	Baylor, Foard, Knox	51 min
Apr 27, 7:15 PM CDT	Severe Thunderstorm Warning	OUN	Wichita, Wilbarger	45 min
Apr 27, 7:44 PM CDT	Severe Thunderstorm Warning	OUN	Baylor, Wilbarger	46 min
Apr 27, 7:53 PM CDT	Tornado Warning	OUN	Wichita	24 min
Apr 27, 7:58 PM CDT	Severe Thunderstorm Warning	OUN	Baylor, Knox, Wilbarger	47 min
Apr 27, 8:39 PM CDT	Severe Thunderstorm Warning	OUN	Archer, Baylor, Wichita, Wilbarger	51 min
Apr 27, 9:06 PM CDT	Special Weather Statement	OUN	Baylor	39 min
Apr 27, 9:35 PM CDT	Special Weather Statement	OUN	Wichita	25 min
Apr 27, 9:54 PM CDT	Special Weather Statement	OUN	Archer	51 min
Apr 27, 10:09 PM CDT	Special Weather Statement	OUN	Wichita	51 min
Apr 27, 10:47 PM CDT	Areal Flood Advisory	OUN	Wichita	118 min
Apr 27, 10:57 PM CDT	Severe Thunderstorm Warning	OUN	Clay	20 min
Apr 27, 11:13 PM CDT	Special Weather Statement	OUN	Clay	47 min
Apr 28, 1:13 AM CDT	Areal Flood Advisory	OUN	Archer, Clay, Wichita	4 hr
Apr 28, 3:11 AM CDT	Flash Flood Warning	OUN	Archer, Clay, Wichita	6 hr
Apr 28, 3:33 AM CDT	Special Weather Statement	OUN	Wichita	27 min
Apr 28, 4:00 AM CDT	Special Weather Statement	OUN	Baylor	30 min
Apr 28, 4:24 AM CDT	Areal Flood Advisory	OUN	Archer, Baylor	3 hr
Apr 28, 4:57 AM CDT	Special Weather Statement	OUN	Clay	33 min
Apr 28, 4:38 PM CDT	Special Weather Statement	OUN	Hardeman	37 min
Apr 28, 5:12 PM CDT	Special Weather Statement	OUN	Foard	33 min

Nearby

Tornado Warnings in Texas, 2021 Every tornado warning in 2021 Tornadoes 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.