Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 2, NWS Tulsa, OK

January 21, 2018LeFlore County, Oklahoma; Sebastian County, Arkansas

NWS Tulsa, OK issued this severe thunderstorm warning at Jan 21, 2018, 6:42 PM CST for LeFlore County, Oklahoma; Sebastian County, Arkansas. It was in force for 33 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: Jan 21, 2018, 6:42 PM CST (00:42 UTC)
Expired: Jan 21, 2018, 7:15 PM CST
In force: 33 min
Issued by: NWS Tulsa, OK
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Sebastian County, AR, LeFlore County, OK

The radar

The Western Arkansas radar (KSRX), 41 km from the middle of the area, began a volume at 00:42 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.

The watch it was issued in

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

Issued	Product	Office	Lasted
Jan 21, 3:05 PM CST	Tornado Watch	SPC	8 hr

The nearest sounding before it

Springfield, MO (KSGF), launched 00:00Z, 0.7 hours before the alert went out and 227 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: 87 J/kg
Mixed-layer CIN: -13 J/kg
Mixed-layer LCL: 971 m above ground
0-6 km bulk shear: 55 kt
0-1 km storm-relative helicity: 232 m²/s²
0-3 km storm-relative helicity: 257 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

The text

As transmitted.

052 
WUUS54 KTSA 220042
SVRTSA
ARC131-OKC079-220115-
/O.NEW.KTSA.SV.W.0002.180122T0042Z-180122T0115Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Tulsa OK
642 PM CST SUN JAN 21 2018

The National Weather Service in Tulsa has issued a

* Severe Thunderstorm Warning for...
  Southwestern Sebastian County in west central Arkansas...
  East central Le Flore County in southeastern Oklahoma...

* Until 715 PM CST

* At 642 PM CST, a severe thunderstorm was located 4 miles southwest
  of Heavener, moving northeast at 50 mph.

  HAZARD...60 mph wind gusts and penny size hail. 

  SOURCE...Radar indicated. 

  IMPACT...Expect damage to roofs, siding, and trees. 

* Locations in or near the path include...
  Poteau...                         Heavener...
  Howe...                           Hartford...
  Cameron...                        Heavener Runestone State Park...
  Patterson...                      Hodgen...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

A tornado watch remains in effect until 1100 PM CST for west central
Arkansas...and southeastern Oklahoma.

LAT...LON 3494 9439 3495 9441 3493 9443 3493 9445
      3489 9445 3471 9466 3479 9477 3519 9455
      3504 9428
TIME...MOT...LOC 0042Z 216DEG 42KT 3484 9465 

HAIL...0.75IN
WIND...60MPH
 
$$

1 follow-up statement

815 
WWUS54 KTSA 220111
SVSTSA

Severe Weather Statement
National Weather Service Tulsa OK
711 PM CST SUN JAN 21 2018

ARC131-OKC079-220121-
/O.EXP.KTSA.SV.W.0002.000000T0000Z-180122T0115Z/
Sebastian AR-Le Flore OK-
711 PM CST SUN JAN 21 2018

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN SEBASTIAN AND
EAST CENTRAL LE FLORE COUNTIES WILL EXPIRE AT 715 PM CST...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore the warning will be allowed to expire.  However gusty winds
are still possible with this thunderstorm.

A tornado watch remains in effect until 1100 PM CST for west central
Arkansas...and southeastern Oklahoma.

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
Tulsa.

LAT...LON 3494 9439 3495 9441 3493 9443 3493 9445
      3489 9445 3471 9466 3479 9477 3519 9455
      3504 9428
TIME...MOT...LOC 0111Z 216DEG 42KT 3510 9442 

$$

The office that day

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

Issued	Product	Office	Counties	Lasted
Jan 21, 6:04 PM CST	Special Weather Statement	TSA	LeFlore	26 min
Jan 21, 6:34 PM CST	Special Weather Statement	TSA	LeFlore	26 min
Jan 21, 7:10 PM CST	Special Weather Statement	TSA	LeFlore	35 min
Jan 21, 7:19 PM CST	Severe Thunderstorm Warning	TSA	McIntosh, Okmulgee	26 min
Jan 21, 7:23 PM CST	Severe Thunderstorm Warning	TSA	LeFlore	37 min
Jan 21, 7:42 PM CST	Special Weather Statement	TSA	McIntosh, Muskogee	33 min
Jan 21, 8:02 PM CST	Severe Thunderstorm Warning	TSA	Muskogee, Wagoner	28 min
Jan 21, 8:25 PM CST	Special Weather Statement	TSA	Cherokee	35 min
Jan 21, 8:27 PM CST	Areal Flood Advisory	TSA	LeFlore, Pushmataha	3 hr
Jan 21, 8:47 PM CST	Special Weather Statement	TSA	LeFlore	28 min
Jan 21, 9:36 PM CST	Special Weather Statement	TSA	LeFlore	39 min
Jan 21, 10:29 PM CST	Special Weather Statement	TSA	LeFlore	31 min
Jan 21, 10:37 PM CST	Severe Thunderstorm Warning	TSA	LeFlore, Sequoyah	23 min
Jan 22, 8:57 AM CST	Wind Advisory	TSA	Creek, Haskell, Latimer, McIntosh, Muskogee, Okfuskee and 6 more	9 hr
Jan 21, 6:02 PM CST	Special Weather Statement	TSA	Crawford	28 min
Jan 21, 6:41 PM CST	Special Weather Statement	TSA	Sebastian	34 min
Jan 21, 6:58 PM CST	Tornado Warning	TSA	Franklin, Sebastian	32 min
Jan 21, 7:26 PM CST	Tornado Warning	TSA	Franklin	34 min
Jan 21, 7:58 PM CST	Special Weather Statement	TSA	Franklin	32 min
Jan 21, 8:08 PM CST	Special Weather Statement	TSA	Benton	37 min
Jan 21, 8:21 PM CST	Special Weather Statement	TSA	Madison	24 min
Jan 21, 9:04 PM CST	Special Weather Statement	TSA	Franklin	26 min
Jan 21, 9:25 PM CST	Special Weather Statement	TSA	Franklin	20 min
Jan 21, 9:35 PM CST	Special Weather Statement	TSA	Madison	25 min
Jan 21, 9:43 PM CST	Severe Thunderstorm Warning	TSA	Carroll, Madison	47 min
Jan 21, 9:48 PM CST	Special Weather Statement	TSA	Washington	27 min
Jan 21, 10:18 PM CST	Special Weather Statement	TSA	Carroll	27 min
Jan 21, 10:56 PM CST	Special Weather Statement	TSA	Crawford, Franklin	34 min
Jan 21, 11:25 PM CST	Special Weather Statement	TSA	Carroll, Madison	35 min

Nearby

Severe Thunderstorm Warnings in Oklahoma, 2018 Severe Thunderstorm Warnings in Arkansas, 2018 Every severe thunderstorm warning in 2018

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.