Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2017
Severe Thunderstorm Warning 785, NWS Norman, OK
NWS Norman, OK issued this severe thunderstorm warning at Aug 12, 2017, 2:30 PM CDT for Jefferson County, Oklahoma; Clay County, Texas. It was in force for 30 min. No storm report in the archive falls inside the area while it was in force.
The area
The counties it named.
The facts
- Issued
- Aug 12, 2017, 2:30 PM CDT (19:30 UTC)
- Expired
- Aug 12, 2017, 3:00 PM CDT
- In force
- 30 min
- Issued by
- NWS Norman, OK
- Area
- Storm-based polygon
- Hail
- 1.0 in
- Wind
- 60.0 mph
Counties Jefferson County, OK, Clay County, TX
The radar
The Altus AFB radar (KFDR), 99 km from the middle of the area, began a volume at 19:31 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
Fort Worth, TX (KFWD), launched 12:00Z, 7.5 hours before the alert went out and 142 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
- 987 J/kg
- Mixed-layer CIN
- -108 J/kg
- Mixed-layer LCL
- 1269 m above ground
- 0-6 km bulk shear
- 14 kt
- 0-1 km storm-relative helicity
- 35 m²/s²
- 0-3 km storm-relative helicity
- 26 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.2
What forecasters said that day
The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Norman, OK wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 12, 12:48 PM CDT, 1 hour 42 minutes earlier.
Area forecast discussion, Aug 12, 12:48 PM CDT, 1 hour 42 minutes before
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</html>Hazardous weather outlook, Aug 12, 11:56 AM CDT, 2 hours 34 minutes before
Hazardous Weather Outlook National Weather Service Norman OK 1156 AM CDT Sat Aug 12 2017 OKZ004>048-050>052-TXZ083>090-131100- Harper-Woods-Alfalfa-Grant-Kay-Ellis-Woodward-Major-Garfield- Noble-Roger Mills-Dewey-Custer-Blaine-Kingfisher-Logan-Payne- Beckham-Washita-Caddo-Canadian-Oklahoma-Lincoln-Grady-McClain- Cleveland-Pottawatomie-Seminole-Hughes-Harmon-Greer-Kiowa-Jackson- Tillman-Comanche-Stephens-Garvin-Murray-Pontotoc-Coal-Cotton- Jefferson-Carter-Johnston-Atoka-Love-Marshall-Bryan-Hardeman- Foard-Wilbarger-Wichita-Knox-Baylor-Archer-Clay- 1156 AM CDT Sat Aug 12 2017 This hazardous weather outlook is for portions of northern... western...central...and southern Oklahoma...and western north Texas. .DAY ONE...This afternoon through Tonight... .Thunderstorms... There is a Slight Risk of severe thunderstorms across parts of southern Oklahoma and western north Texas. A Marginal Risk surrounds the Slight Risk. Location... The Slight Risk area covers locations along and south of a Vernon, Texas to Lawton and Atoka line. Outside the Slight Risk area, a Marginal Risk extends to a line from Quanah, Texas to Hobart, Oklahoma to Pauls Valley to Coalgate. Timing... The most likely time for severe weather will be from 2 pm to 10 pm. Impacts... Half dollar size hail. Wind gusts to 65 mph. Very heavy rainfall. .Discussion... An area of widespread rain and thunderstorms will diminish slowly this afternoon. Strong storms will be possible across the southern part of this rain area. By mid-afternoon, heating will result in moderate instability near a weak frontal boundary near the Red River. Scattered strong to severe storms may develop along and near the front by 2 pm, and continue well into the evening. .SPOTTER AND EMERGENCY MANAGEMENT STATEMENT... Storm spotter groups and emergency management personnel across the risk areas should be ready for severe weather operations. .DAYS TWO THROUGH SEVEN...Sunday through Friday... .Heavy Rain/Flooding... Thunderstorms may produce heavy rainfall across the area Sunday through early next week. A Flood Watch is in effect for most of Oklahoma through sunrise Sunday morning. .Thunderstorms... Thunderstorms will be possible each day. A few strong to severe thunderstorms with damaging winds will be possible at times, but widespread significant severe weather is not expected. Get graphics and more details at weather.gov/norman...and follow our weather forecast office on Twitter and Facebook.
In the hours before
Special weather statement, Aug 12, 10:28 AM CDT, 4 hours 2 minutes before
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</html>Special weather statement, Aug 12, 11:01 AM CDT, 3 hours 29 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE Norman OK
1101 AM CDT SAT AUG 12 2017
OKZ022-023-027-028-035-038>041-044>046-121700-
Grady OK-Kiowa OK-Cotton OK-Washita OK-Stephens OK-Carter OK-
Garvin OK-Caddo OK-McClain OK-Comanche OK-Murray OK-Jefferson OK-
1101 AM CDT SAT AUG 12 2017
...SIGNIFICANT WEATHER ADVISORY FOR Grady...northeastern Kiowa...
northeastern Cotton...southeastern Washita...Stephens...western
Carter...western Garvin...Caddo...southwestern McClain...northeastern
Comanche...west central Murray and Jefferson Counties Until noon
CDT...
AT 1059 AM CDT, strong thunderstorms were along a line extending from
5 miles north of Cooperton to near Fort Sill to near Corum to 3 miles
south of Ryan, moving northeast at 40 MPH.
HAZARDS INCLUDE...
Wind gusts to 40 MPH...
Minor flooding and reduced visibility due to heavy rainfall...
Locations impacted include...
Northeastern Lawton, Duncan, Chickasha, Anadarko, Marlow, Waurika,
Lone Grove, Lindsay, Healdton, Elgin, Wilson, Carnegie, Comanche,
Apache, Rush Springs, Bray, Fletcher, Cyril, Ringling and Mountain
View.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Severe weather is not expected and no warnings are anticipated at
this time.
&&
LAT...LON 3388 9786 3439 9809 3468 9853 3487 9900
3512 9907 3555 9843 3536 9831 3535 9811
3510 9791 3485 9746 3424 9726
TIME...MOT...LOC 1559Z 224DEG 37KT 3495 9886 3467 9854 3436 9807 3397
9793
03Special weather statement, Aug 12, 1:57 PM CDT, 33 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE Norman OK
157 PM CDT SAT AUG 12 2017
TXZ090-121930-
Clay TX-
157 PM CDT SAT AUG 12 2017
...SIGNIFICANT WEATHER ADVISORY FOR southeastern Clay County Until
230 PM CDT...
AT 155 PM CDT, a strong thunderstorm was located over Bellevue,
moving northeast at 20 MPH. A second strong storm was about 5 miles
south of Henrietta.
HAZARDS INCLUDE...
Hail up to the size of nickels...
Wind gusts to 40 MPH...
Locations impacted include...
Bellevue and Vashti.
LAT...LON 3370 9825 3392 9804 3390 9798 3350 9798
3349 9800
TIME...MOT...LOC 1855Z 241DEG 18KT 3363 9802
CMSThe office that day
Everything else NWS Norman, OK issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 12, 6:45 AM CDT | Areal Flood Advisory | OUN | Beckham, Custer, Roger Mills, Washita | 3 hr |
| Aug 12, 10:28 AM CDT | Special Weather Statement | OUN | Kiowa | 62 min |
| Aug 12, 11:01 AM CDT | Special Weather Statement | OUN | Caddo, Carter, Comanche, Grady, Jefferson, Kiowa and 1 more | 59 min |
| Aug 12, 11:09 AM CDT | Areal Flood Advisory | OUN | Caddo, Comanche, Grady, Stephens | 3 hr |
| Aug 12, 1:22 PM CDT | Areal Flood Advisory | OUN | Canadian, Cleveland, Grady, McClain, Oklahoma | 3 hr |
| Aug 12, 3:00 PM CDT | Severe Thunderstorm Warning | OUN | Jefferson | 45 min |
| Aug 12, 3:45 PM CDT | Special Weather Statement | OUN | Stephens | 45 min |
| Aug 12, 1:57 PM CDT | Special Weather Statement | OUN | Clay | 33 min |
| Aug 12, 3:46 PM CDT | Special Weather Statement | OUN | Clay | 59 min |
| Aug 12, 4:10 PM CDT | Special Weather Statement | OUN | Knox | 50 min |
| Aug 12, 4:29 PM CDT | Severe Thunderstorm Warning | OUN | Foard, Knox | 61 min |
| Aug 12, 4:36 PM CDT | Special Weather Statement | OUN | Archer | 24 min |
| Aug 12, 4:58 PM CDT | Severe Thunderstorm Warning | OUN | Baylor | 47 min |
| Aug 12, 5:02 PM CDT | Severe Thunderstorm Warning | OUN | Knox | 43 min |
| Aug 12, 5:42 PM CDT | Special Weather Statement | OUN | Wichita | 33 min |
| Aug 12, 6:00 PM CDT | Special Weather Statement | OUN | Baylor | 30 min |
| Aug 12, 6:27 PM CDT | Severe Thunderstorm Warning | OUN | Baylor | 48 min |
| Aug 12, 6:41 PM CDT | Tornado Warning | OUN | Baylor | 34 min |
Nearby
Severe Thunderstorm Warnings in Oklahoma, 2017Severe Thunderstorm Warnings in Texas, 2017Every severe thunderstorm warning in 2017
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.