Alert archive / Oklahoma / Severe Thunderstorm Watches in 2018

Severe Thunderstorm Watch 207

June 23, 201830 counties in Oklahoma

The Storm Prediction Center issued this severe thunderstorm watch at Jun 23, 2018, 3:56 PM CDT for 30 counties in Oklahoma. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Jun 23, 2018, 3:56 PM CDT (20:56 UTC)
Expired
Jun 23, 2018, 9:55 PM CDT
In force
6 hr
Issued by
the Storm Prediction Center
Largest hail expected
2.5 in
Strongest gust expected
60 kt
All 30 counties

Beckham County, OK, Blaine County, OK, Caddo County, OK, Canadian County, OK, Carter County, OK, Cleveland County, OK, Comanche County, OK, Cotton County, OK, Custer County, OK, Garvin County, OK, Grady County, OK, Greer County, OK, Harmon County, OK, Jackson County, OK, Jefferson County, OK, Johnston County, OK, Kingfisher County, OK, Kiowa County, OK, Lincoln County, OK, Logan County, OK, McClain County, OK, Murray County, OK, Oklahoma County, OK, Pontotoc County, OK, Pottawatomie County, OK, Roger Mills County, OK, Seminole County, OK, Stephens County, OK, Tillman County, OK, Washita County, OK

The radar

The Altus AFB radar (KFDR), 105 km from the middle of the area, began a volume at 20:56 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 SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
20%
One or more EF2 to EF5 tornadoes
2%
Ten or more severe wind reports
40%
One or more gusts of 65 knots or more
20%
Ten or more severe hail reports
50%
One or more hailstones of 2 inches or more
50%
Six or more combined severe hail and wind reports
80%

Warnings issued inside it

3 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Jun 23, 8:03 PM CDTSevere Thunderstorm WarningOUNJackson, Kiowa, Tillman27 min
Jun 23, 8:26 PM CDTSevere Thunderstorm WarningOUNComanche, Tillman49 min
Jun 23, 9:09 PM CDTSevere Thunderstorm WarningOUNComanche, Cotton, Tillman51 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Norman, OK (KOUN), launched 12:00Z, 8.9 hours before the alert went out and 99 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-pSkew-T log-p diagram, Norman, OK at 12:00Z on 2018-06-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Norman, OK at 12:00Z on 2018-06-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -153 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2502 m above ground
0-6 km bulk shear
48 kt
0-1 km storm-relative helicity
-153 m²/s²
0-3 km storm-relative helicity
-38 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.3

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 22, 7:12 PM CDTMesoscale DiscussionSPCAlfalfa, Beaver, Beckham, Blaine, Caddo, Canadian and 22 more2 hr
Jun 22, 9:07 PM CDTMesoscale DiscussionSPCAlfalfa, Beckham, Blaine, Caddo, Canadian, Cleveland and 38 more113 min
Jun 22, 9:27 PM CDTSevere Thunderstorm WatchSPCAtoka, Bryan, Carter, Choctaw, Cleveland, Coal and 38 more6 hr
Jun 22, 11:09 PM CDTMesoscale DiscussionSPCAtoka, Blaine, Bryan, Caddo, Canadian, Carter and 44 more2 hr
Jun 22, 11:48 PM CDTSevere Thunderstorm WatchSPCAdair, Cherokee, LeFlore, McCurtain, Mayes, Sequoyah7 hr
Jun 23, 1:01 AM CDTMesoscale DiscussionSPCAtoka, Blaine, Bryan, Caddo, Canadian, Carter and 44 more59 min
Jun 23, 2:17 PM CDTMesoscale DiscussionSPCBeckham, Caddo, Canadian, Carter, Cleveland, Comanche and 20 more118 min
Jun 23, 2:36 PM CDTMesoscale DiscussionSPCCimarron114 min
Jun 23, 3:20 PM CDTSevere Thunderstorm WatchSPCCimarron7 hr
Jun 23, 6:37 PM CDTMesoscale DiscussionSPCCimarron, Texas113 min

Nearby

Severe Thunderstorm Watches in Oklahoma, 2018Every severe thunderstorm watch 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.