Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2008

Severe Thunderstorm Warning 293, NWS Norman, OK

April 21, 2008Garvin County, McClain County, Pottawatomie County, Oklahoma

NWS Norman, OK issued this severe thunderstorm warning at Apr 21, 2008, 9:37 PM CDT for Garvin County, McClain County, Pottawatomie County, Oklahoma. It was in force for 20 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: Apr 21, 2008, 9:37 PM CDT (02:37 UTC)
Expired: Apr 21, 2008, 9:57 PM CDT
In force: 20 min
Issued by: NWS Norman, OK
Area: Storm-based polygon

Counties Garvin County, OK, McClain County, OK, Pottawatomie County, OK

The radar

The Norman radar (KTLX), 40 km from the middle of the area, began a volume at 02:38 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 21, 8:56 PM CDT	Tornado Watch	SPC	5 hr

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.

Hazardous weather outlook, Apr 21, 7:50 PM CDT, 1 hour 47 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NORMAN OK
750 PM CDT MON APR 21 2008

OKZ004>048-050>052-TXZ083>090-221200-
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-
1200 PM CDT MON APR 21 2008

THIS HAZARDOUS WEATHER OUTLOOK COVERS NORTHERN...WESTERN...
CENTRAL...AND SOUTHERN OKLAHOMA...AND WESTERN NORTH TEXAS.

.DAY ONE...TONIGHT...

THUNDERSTORM OUTLOOK...
THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF
CENTRAL OKLAHOMA.

LOCATION...
THE SLIGHT RISK AREA IS EAST AND NORTH OF A LINE FROM ALFALFA...TO
MARLOW...TO PAULS VALLEY...TO HOLDENVILLE.

TIMING...
THE MOST LIKELY TIME FOR SEVERE THUNDERSTORMS WILL BE BETWEEN 8 PM
AND 12 AM.

RECOMMENDED ACTIONS...
STORM SPOTTER GROUPS AND EMERGENCY MANAGEMENT PERSONNEL ACROSS THE
RISK AREA SHOULD PLAN FOR SEVERE WEATHER THIS EVENING.

DISCUSSION...
THE COLD FRONT WHICH MOVED INTO NORTHERN AND WESTERN OKLAHOMA
EARLIER TODAY HAS BECOME NEARLY STATIONARY FROM NORTH CENTRAL INTO
WEST CENTRAL OKLAHOMA. A DRY LINE EXTENDED FROM THE FRONT IN WEST
CENTRAL OKLAHOMA SOUTHWARD INTO WESTERN NORTH TEXAS. A STRONG CAP
SUPPRESSED THUNDERSTORM DEVELOPMENT THROUGH MUCH OF THE DAY. HOWEVER
EVENING UPPER AIR SOUNDINGS SHOW THAT THE CAP HAD SIGNIFICANTLY
WEAKENED. AS A RESULT THUNDERSTORM DEVELOPMENT WILL BE POSSIBLE THIS
EVENING IN THE VICINITY OF THE FRONT AND DRYLINE...MAINLY ACROSS
PARTS OF CENTRAL OKLAHOMA. MODERATE INSTABILITY AND FAVORABLE DEEP
LAYER SHEAR WILL FAVOR SEVERE STORM DEVELOPMENT. LARGE HAIL AND
DAMAGING WINDS WILL BE THE MAIN THREAT. ISOLATED TORNADOES CAN NOT
BE RULED OUT.

PROBABILITY TABLE...
VALID THROUGH 700 AM CDT TUESDAY APR 22.
PROBABILITY OF THUNDERSTORMS OCCURRING IN THE
              NWS NORMAN COUNTY WARNING AREA...60 PERCENT.
PROBABILITY OF SEVERE STORMS IF STORMS OCCUR...80 PERCENT.

OTHER HAZARDOUS WEATHER...
NONE.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY...

THUNDERSTORM OUTLOOK...
THUNDERSTORM CHANCES WILL RETURN LATE TUESDAY... AND CONTINUE
THROUGH THE REST OF THE WORK WEEK. SEVERE THUNDERSTORMS WILL BE
POSSIBLE... WITH THE BEST CHANCE OF SEVERE WEATHER OVER WESTERN
OKLAHOMA AND WESTERN NORTH TEXAS ON WEDNESDAY.

OTHER HAZARDOUS WEATHER...
NONE.

THE NEXT SCHEDULED HAZARDOUS WEATHER OUTLOOK WILL BE ISSUED AT 7 AM
TUESDAY.

24

In the hours before

Local storm report, Apr 21, 8:31 PM CDT, 1 hour 6 minutes before

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Local storm report, Apr 21, 8:38 PM CDT, 59 minutes before

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Local storm report, Apr 21, 9:16 PM CDT, 21 minutes before

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<head>
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  <meta name="viewport" content="width=device-width, initial-scale=1">
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</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <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.
      </p>
      <p id="message2">
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Local storm report, Apr 21, 9:35 PM CDT, 2 minutes before

<!doctype html>
<html lang="en">
<head>
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  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
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  <script src="index.js"></script>
</body>
</html>

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 21, 8:12 PM CDT	Severe Thunderstorm Warning	OUN	Garvin, McClain	48 min
Apr 21, 8:37 PM CDT	Severe Thunderstorm Warning	OUN	Cleveland, McClain, Pottawatomie	38 min
Apr 21, 8:55 PM CDT	Severe Thunderstorm Warning	OUN	Garvin, McClain, Pottawatomie	50 min
Apr 21, 9:11 PM CDT	Severe Thunderstorm Warning	OUN	Cleveland, Lincoln, Pottawatomie, Seminole	34 min
Apr 21, 9:19 PM CDT	Severe Thunderstorm Warning	OUN	Kay	26 min

Nearby

Severe Thunderstorm Warnings in Oklahoma, 2008 Every severe thunderstorm warning in 2008

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; radar from the NEXRAD Level II archive.