Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2015

Severe Thunderstorm Warning 217, NWS Norman, OK

May 6, 2015Caddo County, Canadian County, Grady County, Oklahoma

NWS Norman, OK issued this severe thunderstorm warning at May 6, 2015, 6:12 PM CDT for Caddo County, Canadian County, Grady County, Oklahoma. It was in force for 48 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 6, 2015, 6:12 PM CDT (23:12 UTC)
Expired: May 6, 2015, 7:00 PM CDT
In force: 48 min
Issued by: NWS Norman, OK
Area: Storm-based polygon
Tornado: Possible
Hail: 1.75 in
Wind: 70.0 mph

Counties Caddo County, OK, Canadian County, OK, Grady County, OK

The radar

The Norman radar (KTLX), 74 km from the middle of the area, began a volume at 23:16 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
May 6, 1:23 PM CDT	Tornado Watch	SPC	8 hr

The nearest sounding before it

Norman, OK (KOUN), launched 12:00Z, 11.2 hours before the alert went out and 62 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1226 J/kg
Mixed-layer CIN: -16 J/kg
Mixed-layer LCL: 562 m above ground
0-6 km bulk shear: 27 kt
0-1 km storm-relative helicity: 219 m²/s²
0-3 km storm-relative helicity: 308 m²/s²
Significant tornado parameter: 1.2
Supercell composite: 9.1

Open this sounding in Storm Lab

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 6, 3:27 PM CDT, 2 hours 45 minutes earlier.

Area forecast discussion, May 6, 3:27 PM CDT, 2 hours 45 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORMAN OK
327 PM CDT WED MAY 6 2015

.DISCUSSION...
A FEW SEVERE STORMS HAVE ALREADY DEVELOPED IN THE MINIMALLY-CAPPED
UNSTABLE/HIGH-SHEAR ATMOSPHERE THAT IS OVER MUCH OF OUR FORECAST
AREA. WE EXPECT A FEW SEVERE STORMS TO CONTINUE THROUGH THE
EVENING....MAINLY IN THE FORM OF ISOLATED SUPERCELLS. UNLIKE LAST
NIGHT...NO ORGANIZED REGION OF HEAVY RAIN IS EXPECTED TONIGHT.
SOME STORMS MAY PERSIST PAST MIDNIGHT...BUT THEY WILL LIKELY
REMAIN SCATTERED...AND NOT AN ORGANIZED COMPLEX.

THE CHANCE FOR RAIN...INCLUDING STRONG/SEVERE STORMS...WILL
PERSIST THROUGH THE REMAINDER OF THE WEEK AND WEEKEND. THERE IS
VERY LITTLE CHANGE TO PREVIOUS THINKING ABOUT EACH DAY...WITH A
LOWER RISK OF SEVERE WEATHER ON THURSDAY...SOMEWHAT HIGHER ON
FRIDAY...MUCH HIGHER ON SATURDAY...AND DIMINISHING FROM WEST TO
EAST ON SUNDAY.

EARLY NEXT WEEK SHOULD BE A COOL AND QUIET PERIOD...FOR A COUPLE
OF DAYS...AT LEAST. MOISTURE AND RAIN CHANCES RISE AGAIN MIDWEEK.

&&

.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK  64  77  64  79 /  50  50  60  50
HOBART OK         62  77  64  79 /  50  50  60  50
WICHITA FALLS TX  64  79  66  79 /  60  50  50  50
GAGE OK           62  80  59  80 /  20  40  60  50
PONCA CITY OK     66  79  63  80 /  40  40  70  50
DURANT OK         65  79  67  80 /  40  40  40  40

&&

.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&

25/23

Hazardous weather outlook, May 6, 3:28 PM CDT, 2 hours 44 minutes before

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE NORMAN OK
328 PM CDT WED MAY 6 2015

OKZ004>048-050>052-TXZ083>090-072030-
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-
328 PM CDT WED MAY 6 2015

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHERN...
WESTERN...CENTRAL...AND SOUTHERN OKLAHOMA...AND WESTERN NORTH
TEXAS.

.DAY ONE...REST OF THIS AFTERNOON AND TONIGHT...

.THUNDERSTORMS...
THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
WESTERN AND CENTRAL OKLAHOMA AND WESTERN NORTH TEXAS.

LOCATION...
THE ENHANCED RISK AREA IS GENERALLY ALONG AND EAST OF A LINE FROM
FREEDOM AND CLINTON... TO ALTUS OKLAHOMA AND BENJAMIN TEXAS... AND
THEN WEST OF A LINE FROM PONCA CITY AND STILLWATER... TO SHAWNEE
AND SULPHUR... TO ARDMORE OKLAHOMA. THIS INCLUDES PLACES SUCH AS
ENID... THE OKLAHOMA CITY METRO... LAWTON... AND WICHITA FALLS.

TIMING...
THROUGH MIDNIGHT

IMPACTS...
HAIL UP TO THE SIZE OF BASEBALLS...
WIND GUSTS OF 60 TO 70 MPH...
A FEW TORNADOES...
LOCALLY HEAVY RAINFALL WHICH COULD CAUSE SOME FLOODING...

.SPOTTER AND EMERGENCY MANAGEMENT STATEMENT...

STORM SPOTTER GROUPS AND EMERGENCY MANAGEMENT PERSONNEL IN THE
RISK AREAS SHOULD BE READY FOR SEVERE WEATHER OPERATIONS.

DISCUSSION...
A FEW THUNDERSTORMS WILL DEVELOP AND MOVE ACROSS PARTS OF OKLAHOMA
AND WESTERN NORTH TEXAS. EVEN THOUGH THERE MAY ONLY BE A FEW
STORMS... ANY STORM THAT DEVELOPS WILL BE SEVERE DUE TO HIGH
INSTABILITY AND STRONG WIND SHEAR. VERY LARGE HAIL... DAMAGING
WIND GUSTS... AND TORNADOES WILL BE POSSIBLE. THUNDERSTORM
INTENSITY IS EXPECTED TO GRADUALLY WEAKEN DURING THE OVERNIGHT
HOURS...BUT STORMS MAY STILL PRODUCE LOCALLY HEAVY RAINFALL AND
SOME HAIL.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY...

.THUNDERSTORMS...
A VERY ACTIVE WEATHER PATTERN WILL REMAIN IN PLACE THROUGH AT
LEAST SUNDAY. SEVERE STORMS WILL BE POSSIBLE EACH DAY...ESPECIALLY
DURING THE MID AFTERNOON INTO THE LATE EVENING. AT THIS
TIME...SATURDAY MAY HAVE THE GREATEST POTENTIAL FOR SEVERE WEATHER
AS A STRONG STORM SYSTEM APPROACHES THE SOUTHERN PLAINS.

GET GRAPHICS AND MORE DETAILS AT WEATHER.GOV/NORMAN...AND FOLLOW
OUR WEATHER FORECAST OFFICE ON TWITTER AND FACEBOOK.

In the hours before

Local storm report, May 6, 5:24 PM CDT, 48 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
524 PM CDT WED MAY 06 2015

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0510 PM     HAIL             3 W TRUSCOTT            33.75N 99.86W
05/06/2015  M1.50 INCH       KNOX               TX   CO-OP OBSERVER

&&

FM

Local storm report, May 6, 5:33 PM CDT, 39 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
533 PM CDT WED MAY 06 2015

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0530 PM     HAIL             4 SE CROWELL            33.94N 99.67W
05/06/2015  E1.75 INCH       FOARD              TX   TRAINED SPOTTER

&&

FM

Local storm report, May 6, 5:47 PM CDT, 25 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
547 PM CDT WED MAY 06 2015

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0546 PM     HAIL             HILLSDALE               36.56N 97.99W
05/06/2015  E1.75 INCH       GARFIELD           OK   EMERGENCY MNGR

&&

FM

Local storm report, May 6, 5:49 PM CDT, 23 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
549 PM CDT WED MAY 06 2015

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0546 PM     TORNADO          4 WNW NORMAN            35.24N 97.51W
05/06/2015                   CLEVELAND          OK   STORM CHASER

            BRIEF TOUCHDOWN AT THE INTERSECTION OF 48TH AND ROBINSON.

&&

FM

Local storm report, May 6, 5:55 PM CDT, 17 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
555 PM CDT WED MAY 06 2015

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0551 PM     TSTM WND GST     5 WNW NORMAN            35.25N 97.52W
05/06/2015  E70.00 MPH       CLEVELAND          OK   TRAINED SPOTTER

            ROTATING WALL CLOUD REPORTED AS WELL.

&&

FM

Local storm report, May 6, 6:12 PM CDT, 0 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
612 PM CDT WED MAY 06 2015

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0604 PM     HAIL             7 W ANADARKO            35.08N 98.37W
05/06/2015  E1.00 INCH       CADDO              OK   AMATEUR RADIO

&&

FM

The office that day

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

Issued	Product	Office	Counties	Lasted
May 5, 9:12 PM CDT	Special Weather Statement	OUN	Harmon	33 min
May 5, 10:20 PM CDT	Special Weather Statement	OUN	Grady	25 min
May 5, 10:44 PM CDT	Special Weather Statement	OUN	Grady	31 min
May 5, 10:47 PM CDT	Severe Thunderstorm Warning	OUN	Kiowa	28 min
May 5, 11:41 PM CDT	Flash Flood Warning	OUN	Caddo, Canadian, Comanche, Grady, Kiowa	3 hr
May 5, 11:47 PM CDT	Special Weather Statement	OUN	Logan, Oklahoma	28 min
May 5, 11:56 PM CDT	Special Weather Statement	OUN	Grady	34 min
May 6, 12:00 AM CDT	Severe Thunderstorm Warning	OUN	Garfield, Noble	30 min
May 6, 12:21 AM CDT	Areal Flood Advisory	OUN	Cleveland, Oklahoma	114 min
May 6, 12:27 AM CDT	Severe Thunderstorm Warning	OUN	Canadian, Cleveland, Grady, Kingfisher, Logan, McClain and 2 more	48 min
May 6, 1:02 AM CDT	Severe Thunderstorm Warning	OUN	Carter, Garvin, Murray	28 min
May 6, 1:40 AM CDT	Flash Flood Warning	OUN	Cleveland, McClain	3 hr
May 6, 2:11 AM CDT	Areal Flood Advisory	OUN	Grady, Stephens	3 hr
May 6, 2:42 AM CDT	Severe Thunderstorm Warning	OUN	Pottawatomie, Seminole	33 min
May 6, 3:11 AM CDT	Special Weather Statement	OUN	McClain, Pottawatomie	34 min
May 6, 3:36 AM CDT	Areal Flood Advisory	OUN	Hughes, Pottawatomie, Seminole	3 hr
May 6, 3:41 AM CDT	Severe Thunderstorm Warning	OUN	Hughes, Seminole	34 min
May 6, 6:10 AM CDT	River Flood Warning	OUN	Pottawatomie, Seminole	5 days
May 6, 6:46 AM CDT	Special Weather Statement	OUN	Lincoln	29 min
May 6, 12:46 PM CDT	Severe Thunderstorm Warning	OUN	Caddo	26 min
May 6, 2:11 PM CDT	Severe Thunderstorm Warning	OUN	Caddo, Comanche	49 min
May 6, 2:45 PM CDT	Tornado Warning	OUN	Caddo	30 min
May 6, 3:03 PM CDT	Severe Thunderstorm Warning	OUN	Blaine, Major	42 min
May 6, 3:10 PM CDT	Tornado Warning	OUN	Caddo, Grady	35 min
May 6, 3:35 PM CDT	Special Weather Statement	OUN	Cleveland, Oklahoma	25 min
May 6, 3:43 PM CDT	Tornado Warning	OUN	Grady	32 min
May 6, 3:45 PM CDT	Severe Thunderstorm Warning	OUN	Alfalfa, Blaine, Garfield, Grant, Major	45 min
May 6, 4:03 PM CDT	Tornado Warning	OUN	Alfalfa, Garfield, Grant, Major	27 min
May 6, 4:12 PM CDT	Tornado Warning	OUN	Grady	33 min
May 6, 4:27 PM CDT	Tornado Warning	OUN	Major	33 min
May 6, 4:43 PM CDT	Tornado Warning Emergency	OUN	Grady, McClain	47 min
May 6, 4:48 PM CDT	Severe Thunderstorm Warning	OUN	Custer, Dewey	42 min
May 6, 4:52 PM CDT	Tornado Warning	OUN	Alfalfa, Garfield, Major	23 min
May 6, 5:15 PM CDT	Tornado Warning	OUN	Alfalfa, Garfield, Grant, Major	30 min
May 6, 5:21 PM CDT	Severe Thunderstorm Warning	OUN	Caddo, Grady	39 min
May 6, 5:24 PM CDT	Severe Thunderstorm Warning	OUN	Blaine, Dewey	51 min
May 6, 5:25 PM CDT	Tornado Warning EmergencyTornado observedCatastrophic damage threat	OUN	Cleveland, Grady, McClain	9 min
May 6, 5:29 PM CDT	Tornado Warning	OUN	Cleveland, McClain	31 min
May 6, 5:44 PM CDT	Tornado Warning	OUN	Garfield, Grant	31 min
May 6, 5:55 PM CDT	Severe Thunderstorm Warning	OUN	Jackson, Tillman	50 min
May 6, 5:56 PM CDT	Tornado Warning	OUN	Cleveland	34 min
May 6, 6:04 PM CDT	Severe Thunderstorm Warning	OUN	Alfalfa, Grant	41 min
May 6, 6:04 PM CDT	Severe Thunderstorm Warning	OUN	Cotton, Tillman	16 min
May 6, 6:06 PM CDT	Flash Flood Warning Emergency	OUN	Caddo, Canadian, Cleveland, Grady, McClain, Oklahoma	15 hr
May 6, 6:09 PM CDT	Severe Thunderstorm Warning	OUN	Cleveland, Oklahoma	51 min
May 6, 6:13 PM CDT	Severe Thunderstorm Warning	OUN	Grant	32 min
May 6, 6:17 PM CDT	Tornado Warning	OUN	Cleveland, Oklahoma	28 min
May 6, 6:18 PM CDT	Severe Thunderstorm Warning	OUN	Blaine, Dewey, Major	42 min
May 6, 6:21 PM CDT	Severe Thunderstorm Warning	OUN	Alfalfa	24 min
May 6, 6:31 PM CDT	Tornado Warning	OUN	Caddo, Canadian, Grady	29 min
May 6, 6:36 PM CDT	Tornado Warning Tornado observed	OUN	Blaine, Dewey, Major	24 min
May 6, 6:39 PM CDT	Tornado Warning	OUN	Cleveland, Lincoln, Oklahoma, Pottawatomie	20 min
May 6, 6:43 PM CDT	Severe Thunderstorm Warning	OUN	Alfalfa, Grant	32 min
May 6, 6:48 PM CDT	Severe Thunderstorm Warning	OUN	Jackson, Kiowa, Tillman	29 min
May 6, 6:57 PM CDT	Tornado Warning	OUN	Grant	33 min
May 6, 6:57 PM CDT	Tornado Warning Tornado observed	OUN	Grady	33 min
May 5, 10:56 PM CDT	Special Weather Statement	OUN	Foard	34 min
May 5, 11:05 PM CDT	Severe Thunderstorm Warning	OUN	Foard, Hardeman	40 min
May 6, 4:15 PM CDT	Special Weather Statement	OUN	Knox	30 min
May 6, 4:35 PM CDT	Severe Thunderstorm Warning	OUN	Knox	40 min
May 6, 4:54 PM CDT	Severe Thunderstorm Warning	OUN	Baylor, Knox	21 min
May 6, 5:02 PM CDT	Severe Thunderstorm Warning	OUN	Foard, Knox	13 min
May 6, 5:12 PM CDT	Severe Thunderstorm Warning	OUN	Baylor, Foard, Hardeman, Knox, Wilbarger	63 min
May 6, 5:15 PM CDT	Severe Thunderstorm Warning	OUN	Baylor, Knox, Wilbarger	45 min
May 6, 5:48 PM CDT	Severe Thunderstorm Warning	OUN	Baylor	42 min
May 6, 6:24 PM CDT	Severe Thunderstorm Warning	OUN	Archer, Baylor, Wichita, Wilbarger	51 min

Nearby

Severe Thunderstorm Warnings in Oklahoma, 2015 Every severe thunderstorm warning in 2015

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.