Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2009
Severe Thunderstorm Warning 340, NWS Norman, OK
NWS Norman, OK issued this severe thunderstorm warning at May 12, 2009, 9:49 AM CDT for Lincoln County, Logan County, Payne County, Oklahoma. It was in force for 41 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
- May 12, 2009, 9:49 AM CDT (14:49 UTC)
- Expired
- May 12, 2009, 10:30 AM CDT
- In force
- 41 min
- Issued by
- NWS Norman, OK
- Area
- Storm-based polygon
Counties Lincoln County, OK, Logan County, OK, Payne County, OK
The radar
The Norman radar (KTLX), 65 km from the middle of the area, began a volume at 14:49 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
Norman, OK (KOUN), launched 12:00Z, 2.8 hours before the alert went out and 80 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 439 m above ground
- 0-6 km bulk shear
- 31 kt
- 0-1 km storm-relative helicity
- 177 m²/s²
- 0-3 km storm-relative helicity
- 304 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 6.4
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 May 12, 6:16 AM CDT, 3 hours 33 minutes earlier.
Area forecast discussion, May 12, 6:16 AM CDT, 3 hours 33 minutes before
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORMAN OK 616 AM CDT TUE MAY 12 2009 .AVIATION... WIDESPREAD IFR AND LIFR CEILINGS AND VISIBILITIES ARE EXPECTED TO IMPROVE SLOWLY THIS MORNING. GENERALLY VFR CONDITIONS ARE EXPECTED BY LATE AFTERNOON OR EARLY EVENING... BUT MVFR CEILINGS WILL BE LIKELY AGAIN AFTER DARK AT KPNC... KOKC... AND KOUN. A FEW THUNDERSTORMS WILL BE POSSIBLE AT MOST SITES... BUT THE HIGHEST CHANCE THIS MORNING WILL BE KOKC AND KOUN... WHILE BETWEEN 13/00Z AND 13/06Z THE GREATEST CHANCES WILL BE KCSM... KHBR... KLAW... AND KSPS... BUT ONLY KHBR IS 30 PERCENT OR MORE. && .PREV DISCUSSION... /ISSUED 407 AM CDT TUE MAY 12 2009/ DISCUSSION... THE COMPLICATED WEATHER PATTERN CONTINUES... AS A SERIES OF WAVES MOVE THROUGH THE WESTERLY FLOW ALOFT. WE START OUT THIS MORNING WITH JUST A FEW SMALL ECHOES ON RADAR... AND WIDESPREAD LOW CLOUDS WITH SOME AREAS OF FOG. AS A WEAK IMPULSE MOVES THROUGH THE UPPER- LEVEL FLOW TODAY... AND AS ISENTROPIC LIFT OVER THE COOL AIR AT THE SURFACE CONTINUES... RAIN CHANCES WILL BE ON THE INCREASE THIS MORNING. BY AFTERNOON... SOME BREAKS IN THE CLOUD COVER SHOULD ALLOW MOST OF OUR AREA TO BE WARMER THAN THE PAST SEVERAL DAYS. MOST OF THE AREA SHOULD REMAIN DRY... MEANING RAIN-FREE... TONIGHT. HOWEVER... THERE ARE INDICATIONS THAT SOME SEVERE STORMS MAY BREAK OUT OVER WEST TEXAS... AND SOME OF THESE STORMS MAY SURVIVE LONG ENOUGH TO ENTER OUR SOUTHWESTERN COUNTIES THIS EVENING. FOR WEDNESDAY... A COLD FRONT WILL MOVE INTO OKLAHOMA... AND WILL GREATLY INCREASE THE CHANCES FOR WIDESPREAD STORMS ONCE AGAIN. THE STORMS ARE LIKELY TO FORM LATE IN THE DAY... AND LAST WELL INTO THE NIGHT. REMAINING BOUNDARIES... MOISTURE... ETC... WILL ALLOW CONTINUING CHANCES OF SHOWERS AND STORMS INTO THURSDAY. AFTER A BRIEF BREAK IN THE ACTION ON FRIDAY... ANOTHER COLD FRONT ENTERS THE SCENE FRIDAY EVENING AND SATURDAY... ONCE AGAIN BRINGING A HIGHER CHANCE OF WIDESPREAD RAIN AND THUNDERSTORMS. FOR SUNDAY INTO EARLY NEXT WEEK... COOL HIGH PRESSURE BUILDS INTO THE SOUTHERN PLAINS... AND SHOULD PROVIDE A FEW QUIET DAYS WITH MILD TEMPERATURES AND RELATIVELY DRY AIR. WITH A FEW MAJOR EXCEPTIONS... THE GFS MOS WAS ADEQUATE FOR THIS FORECAST PACKAGE. HOWEVER... MANUAL INTERVENTION WAS REQUIRED FOR TEMPERATURES AND POPS IN MOST PERIODS THROUGH SATURDAY. A FEW MISCELLANEOUS ADJUSTMENTS WERE ALSO NEEDED TO FIX UNREALISTIC GRADIENTS. && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 77 68 83 58 / 50 10 20 60 HOBART OK 82 67 87 58 / 30 20 10 30 WICHITA FALLS TX 84 69 90 62 / 30 10 10 20 GAGE OK 79 68 78 50 / 40 10 10 20 PONCA CITY OK 73 69 81 55 / 60 10 30 50 DURANT OK 79 68 87 66 / 40 10 10 30 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...NONE. TX...NONE. && 24/23/23
Hazardous weather outlook, May 12, 8:55 AM CDT, 54 minutes before
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<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>
</main>
<script src="index.js"></script>
</body>
</html>In the hours before
Local storm report, May 12, 9:14 AM CDT, 35 minutes before
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<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>
</main>
<script src="index.js"></script>
</body>
</html>Local storm report, May 12, 9:23 AM CDT, 26 minutes before
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<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>
</main>
<script src="index.js"></script>
</body>
</html>Special weather statement, May 12, 9:26 AM CDT, 23 minutes before
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<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>
</main>
<script src="index.js"></script>
</body>
</html>Special weather statement, May 12, 9:27 AM CDT, 22 minutes before
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<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>
</main>
<script src="index.js"></script>
</body>
</html>Special weather statement, May 12, 9:34 AM CDT, 15 minutes before
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<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>
</main>
<script src="index.js"></script>
</body>
</html>Local storm report, May 12, 9:43 AM CDT, 6 minutes before
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<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>
</main>
<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 |
|---|---|---|---|---|
| May 12, 7:22 AM CDT | Severe Thunderstorm Warning | OUN | Grady, McClain | 23 min |
| May 12, 7:43 AM CDT | Severe Thunderstorm Warning | OUN | Cleveland | 47 min |
| May 12, 8:07 AM CDT | Severe Thunderstorm Warning | OUN | Hughes, Pontotoc, Seminole | 53 min |
| May 12, 8:14 AM CDT | Severe Thunderstorm Warning | OUN | Cleveland, Lincoln, Pottawatomie, Seminole | 46 min |
| May 12, 8:20 AM CDT | Severe Thunderstorm Warning | OUN | Cleveland, Grady, McClain, Oklahoma | 40 min |
| May 12, 8:36 AM CDT | Severe Thunderstorm Warning | OUN | Alfalfa, Grant, Kay | 54 min |
| May 12, 8:51 AM CDT | Severe Thunderstorm Warning | OUN | Hughes, Pontotoc, Seminole | 39 min |
| May 12, 8:57 AM CDT | Severe Thunderstorm Warning | OUN | Cleveland, McClain, Oklahoma | 48 min |
| May 12, 9:33 AM CDT | Severe Thunderstorm Warning | OUN | Hughes, Pontotoc, Seminole | 42 min |
| May 12, 9:45 AM CDT | Severe Thunderstorm Warning | OUN | Lincoln, Oklahoma, Pottawatomie | 47 min |
| May 12, 10:08 AM CDT | Severe Thunderstorm Warning | OUN | Hughes, Seminole | 52 min |
| May 12, 11:39 AM CDT | Areal Flood Advisory | OUN | Atoka, Coal | 3 hr |
Nearby
Severe Thunderstorm Warnings in Oklahoma, 2009Every severe thunderstorm warning in 2009
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.