Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2020
Severe Thunderstorm Warning 585, NWS Norman, OK
NWS Norman, OK issued this severe thunderstorm warning at Jul 29, 2020, 10:23 PM CDT for Alfalfa County, Woods County, Oklahoma. It was in force for 36 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
- Jul 29, 2020, 10:23 PM CDT (03:23 UTC)
- Expired
- Jul 29, 2020, 10:59 PM CDT
- In force
- 36 min
- Issued by
- NWS Norman, OK
- Area
- Storm-based polygon
- Hail
- 0.75 in
- Wind
- 60.0 mph
Counties Alfalfa County, OK, Woods County, OK
The radar
The Vance AFB radar (KVNX), 42 km from the middle of the area, began a volume at 03:25 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
Dodge City, (KDDC), launched 00:00Z, 3.4 hours before the alert went out and 162 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
- 1771 J/kg
- Mixed-layer CIN
- -4 J/kg
- Mixed-layer LCL
- 1553 m above ground
- 0-6 km bulk shear
- 27 kt
- 0-1 km storm-relative helicity
- 55 m²/s²
- 0-3 km storm-relative helicity
- 95 m²/s²
- Significant tornado parameter
- 0.2
- Supercell composite
- 3.2
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 Jul 29, 7:32 PM CDT, 2 hours 51 minutes earlier.
Area forecast discussion, Jul 29, 7:32 PM CDT, 2 hours 51 minutes before
Area Forecast Discussion National Weather Service Norman OK 732 PM CDT Wed Jul 29 2020 ...New AVIATION... .SHORT TERM... (This evening through Thursday) Issued at 227 PM CDT Wed Jul 29 2020 The main concerns for the short term period are the Slight Risk for severe thunderstorms over NW Oklahoma (including portions of Harper, Woodward, Woods, and Alfalfa Counties) and the Slight Risk for excessive rainfall, especially over northern Oklahoma, in association with a midlevel trough tracking SE from the WY/SD/NE junction. Though previous guidance had shown a severe MCS descending from KS into northern Oklahoma late tonight/early tomorrow morning, the latest model runs have backed off on both the amount and severity of rain/storms that reach northern Oklahoma. Have cancelled the Flood Watch for now as QPF is not anticipated to be appreciable over areas with saturated soils. Chances for precipitation expand southward across the FA throughout the day tomorrow as another shortwave descends from the high plains. There is a Marginal Risk that storms on Thursday could be severe and produce large hail and damaging winds. Thompson && .LONG TERM... (Thursday night through next Tuesday) Issued at 213 PM CDT Wed Jul 29 2020 Showers and thunderstorms will continue overnight Thursday night, ending west to east on Friday as a upper level trough and associated front make their way southeast across the central and southern plains. Cooler, drier air will lag behind Thursday's front keeping temperatures below normal well into next week and limiting rain chances over the weekend. Both deterministic and ensemble models suggest the possibility of an MCS Sunday night into Monday morning. Raised PoPs well above initialized guidance (which tends to under perform with MCS's) through this period. Ensemble cluster analysis continues to show midweek as the most likely time for a pattern change with the upper high building back, though there is still a significant amount of variance among ensemble members. Day && .AVIATION... (00Z TAFS) Issued at 709 PM CDT Wed Jul 29 2020 Generally, VFR weather is expected. Thunderstorms may move into northern Oklahoma late this evening and early Thursday. Otherwise, a front from the north on Thursday afternoon will bring scattered showers and thunderstorms to the northern half of Oklahoma. && .PRELIMINARY POINT TEMPS/POPS... Oklahoma City OK 72 91 70 82 / 10 30 60 50 Hobart OK 73 96 69 85 / 10 30 50 30 Wichita Falls TX 76 98 70 88 / 10 20 50 30 Gage OK 68 90 65 84 / 20 40 40 20 Ponca City OK 70 88 68 80 / 50 50 60 50 Durant OK 76 97 72 88 / 10 20 60 50 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...None. TX...None. && SHORT TERM...01 LONG TERM....14 AVIATION...09
Hazardous weather outlook, Jul 29, 9:42 PM CDT, 41 minutes before
Hazardous Weather Outlook...UPDATED National Weather Service Norman OK 942 PM CDT Wed Jul 29 2020 OKZ004>048-050>052-TXZ083>090-301130- 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- 942 PM CDT Wed Jul 29 2020 This hazardous weather outlook is for portions of northern... western...central...and southern Oklahoma...and western north Texas. .DAY ONE...Through tonight... .Thunderstorms... There is a risk of strong to severe thunderstorms across the northern third of Oklahoma. The stronger storms will produce wind gusts near 60 mph and locally heavy rainfall. Some hail is also possible. The most likely time for severe storms will be from the mid evening through about 2 am. .DAYS TWO THROUGH SEVEN...Thursday through Tuesday... .Thunderstorms... Thunderstorm chances will continue through late Friday with the highest chances Thursday night into Friday morning. Strong to severe storms will be possible Thursday afternoon into the overnight hours Thursday night, with damaging winds, large hail and locally heavy rain the main concerns. Most of Saturday and Sunday will be dry, but thunderstorm chances will increase Sunday night through Monday morning. 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, Jul 29, 5:01 PM CDT, 5 hours 22 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE Norman OK 501 PM CDT Wed Jul 29 2020 OKZ023-027-292230- Grady OK-Caddo OK- 501 PM CDT Wed Jul 29 2020 ...SIGNIFICANT WEATHER ADVISORY FOR west central Grady and southeastern Caddo Counties Until 530 PM CDT... AT 458 PM CDT, a strong thunderstorm was located near Verden, moving east at 20 MPH. HAZARDS INCLUDE... Minor flooding in areas of poor drainage... Locations impacted include... Chickasha and Verden. This includes Interstate 44 between mile markers 79 and 85. LAT...LON 3501 9816 3510 9814 3510 9788 3501 9785 TIME...MOT...LOC 2158Z 269DEG 18KT 3506 9805 WR
Special weather statement, Jul 29, 5:30 PM CDT, 4 hours 53 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE Norman OK 530 PM CDT Wed Jul 29 2020 OKZ023-027-292300- Grady OK-Caddo OK- 530 PM CDT Wed Jul 29 2020 ...SIGNIFICANT WEATHER ADVISORY FOR west central Grady and east central Caddo Counties Until 600 PM CDT... AT 529 PM CDT, a strong thunderstorm was located over Lake Chickasha, moving east at 25 MPH. HAZARDS INCLUDE... Hail up to the size of nickels... Wind gusts to 40 MPH... Minor flooding in areas of poor drainage... Heavy rain can lead to reduced visibility... Locations impacted include... Lake Chickasha. LAT...LON 3509 9820 3517 9823 3522 9801 3512 9790 TIME...MOT...LOC 2229Z 258DEG 20KT 3514 9813 WR
Special weather statement, Jul 29, 6:01 PM CDT, 4 hours 22 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE Norman OK 601 PM CDT Wed Jul 29 2020 OKZ023-027-292330- Grady OK-Caddo OK- 601 PM CDT Wed Jul 29 2020 ...SIGNIFICANT WEATHER ADVISORY FOR west central Grady and southeastern Caddo Counties Until 630 PM CDT... AT 558 PM CDT, a strong thunderstorm was located near Lake Chickasha, moving east at 15 MPH. HAZARDS INCLUDE... Hail up to one-half inch diameter... Wind gusts to 50 MPH... Minor flooding in areas of poor drainage... Heavy rain can lead to reduced visibility... Locations impacted include... Verden, Amber, Pocasset and Lake Chickasha. LAT...LON 3508 9810 3516 9816 3521 9791 3511 9786 TIME...MOT...LOC 2258Z 250DEG 11KT 3514 9808 WR
Special weather statement, Jul 29, 8:49 PM CDT, 1 hour 34 minutes before
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</head>
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<div class="status" id="status">Temporary Notice</div>
<h1 id="headline">This service is currently unavailable.</h1>
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The site you requested is temporarily down for maintenance or an unexpected outage.
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<p id="message2">
Please try again in a few minutes.
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</html>The office that day
Everything else NWS Norman, OK issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 29, 8:49 PM CDT | Special Weather Statement | OUN | Harper | 26 min |
| Jul 29, 9:15 PM CDT | Special Weather Statement | OUN | Harper | 30 min |
| Jul 29, 9:45 PM CDT | Severe Thunderstorm Warning | OUN | Alfalfa, Woods, Woodward | 45 min |
| Jul 29, 10:36 PM CDT | Special Weather Statement | OUN | Alfalfa | 24 min |
| Jul 29, 11:51 PM CDT | Special Weather Statement | OUN | Grant, Kay, Noble | 24 min |
| Jul 30, 12:15 AM CDT | Special Weather Statement | OUN | Kay, Noble | 30 min |
| Jul 30, 1:53 AM CDT | Special Weather Statement | OUN | Payne | 37 min |
| Jul 30, 2:37 AM CDT | Special Weather Statement | OUN | Harper | 38 min |
| Jul 30, 3:18 AM CDT | Special Weather Statement | OUN | Harper | 27 min |
| Jul 30, 3:57 AM CDT | Special Weather Statement | OUN | Alfalfa, Grant, Woods | 33 min |
| Jul 30, 4:14 AM CDT | Severe Thunderstorm Warning | OUN | Alfalfa, Garfield, Grant | 46 min |
| Jul 30, 4:38 AM CDT | Severe Thunderstorm Warning | OUN | Alfalfa, Blaine, Garfield, Kingfisher, Major | 37 min |
| Jul 30, 4:56 AM CDT | Severe Thunderstorm Warning | OUN | Garfield, Grant, Kay, Kingfisher, Logan, Noble and 1 more | 49 min |
| Jul 30, 5:46 AM CDT | Special Weather Statement | OUN | Lincoln, Logan, Oklahoma, Payne | 29 min |
| Jul 30, 6:15 AM CDT | Special Weather Statement | OUN | Lincoln, Oklahoma | 30 min |
| Jul 30, 6:48 AM CDT | Areal Flood Advisory | OUN | Kay | 3 hr |
| Jul 30, 3:23 PM CDT | Special Weather Statement | OUN | Washita | 22 min |
| Jul 30, 4:18 PM CDT | Special Weather Statement | OUN | Kiowa | 27 min |
| Jul 30, 4:22 PM CDT | Severe Thunderstorm Warning | OUN | Greer, Jackson, Kiowa | 23 min |
| Jul 30, 4:28 PM CDT | Severe Thunderstorm Warning | OUN | Kiowa | 17 min |
| Jul 30, 4:43 PM CDT | Special Weather Statement | OUN | Hughes | 17 min |
| Jul 30, 4:48 PM CDT | Severe Thunderstorm Warning | OUN | Comanche, Greer, Jackson, Kiowa, Tillman | 42 min |
| Jul 30, 4:51 PM CDT | Special Weather Statement | OUN | Grady | 24 min |
| Jul 30, 5:00 PM CDT | Special Weather Statement | OUN | Tillman | 15 min |
| Jul 30, 5:03 PM CDT | Special Weather Statement | OUN | Coal | 27 min |
| Jul 30, 5:07 PM CDT | Severe Thunderstorm Warning | OUN | Comanche, Grady, Stephens | 38 min |
| Jul 30, 5:28 PM CDT | Severe Thunderstorm Warning | OUN | Coal, Hughes | 32 min |
| Jul 30, 5:29 PM CDT | Severe Thunderstorm Warning | OUN | Comanche, Cotton, Tillman | 46 min |
| Jul 30, 5:35 PM CDT | Severe Thunderstorm Warning | OUN | Garvin, McClain | 40 min |
| Jul 30, 5:40 PM CDT | Severe Thunderstorm Warning | OUN | Comanche, Cotton, Stephens | 50 min |
| Jul 30, 5:43 PM CDT | Special Weather Statement | OUN | McClain | 17 min |
| Jul 30, 6:07 PM CDT | Severe Thunderstorm Warning | OUN | Carter, Garvin, Grady, McClain, Stephens | 23 min |
| Jul 30, 6:14 PM CDT | Severe Thunderstorm Warning | OUN | Comanche, Cotton, Jefferson, Stephens, Tillman | 16 min |
| Jul 30, 6:19 PM CDT | Severe Thunderstorm Warning | OUN | Atoka, Coal, Pontotoc | 26 min |
| Jul 30, 6:27 PM CDT | Severe Thunderstorm Warning | OUN | Carter, Cotton, Garvin, Jefferson, Johnston, Love and 4 more | 48 min |
| Jul 30, 6:30 PM CDT | Areal Flood Advisory | OUN | Coal, Hughes | 3 hr |
| Jul 30, 6:31 PM CDT | Severe Thunderstorm Warning | OUN | Comanche, Cotton, Tillman | 44 min |
| Jul 30, 6:36 PM CDT | Special Weather Statement | OUN | Pontotoc | 24 min |
| Jul 30, 6:52 PM CDT | Special Weather Statement | OUN | Ellis | 23 min |
| Jul 30, 6:56 PM CDT | Severe Thunderstorm Warning | OUN | Atoka, Coal, Hughes, Johnston, Pontotoc | 19 min |
| Jul 30, 4:06 PM CDT | Special Weather Statement | OUN | Wilbarger | 24 min |
| Jul 30, 4:14 PM CDT | Severe Thunderstorm Warning | OUN | Wilbarger | 31 min |
| Jul 30, 4:25 PM CDT | Severe Thunderstorm Warning | OUN | Foard | 20 min |
| Jul 30, 4:39 PM CDT | Severe Thunderstorm Warning | OUN | Wilbarger | 51 min |
| Jul 30, 4:41 PM CDT | Severe Thunderstorm Warning | OUN | Foard, Knox | 49 min |
| Jul 30, 5:26 PM CDT | Severe Thunderstorm Warning | OUN | Archer, Baylor, Wichita, Wilbarger | 49 min |
| Jul 30, 5:33 PM CDT | Severe Thunderstorm Warning | OUN | Baylor, Foard, Hardeman, Wilbarger | 27 min |
| Jul 30, 5:45 PM CDT | Severe Thunderstorm Warning | OUN | Foard, Wilbarger | 30 min |
| Jul 30, 5:54 PM CDT | Special Weather Statement | OUN | Knox | 36 min |
| Jul 30, 6:10 PM CDT | Severe Thunderstorm Warning | OUN | Foard, Hardeman, Wilbarger | 39 min |
| Jul 30, 6:41 PM CDT | Special Weather Statement | OUN | Wichita | 34 min |
| Jul 30, 6:55 PM CDT | Special Weather Statement | OUN | Baylor | 35 min |
Nearby
Severe Thunderstorm Warnings in Oklahoma, 2020Every severe thunderstorm warning in 2020
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.