Alert archive / Oklahoma / Severe Thunderstorm Warnings in 1999

Severe Thunderstorm Warning 178, NWS Norman, OK

April 26, 1999Alfalfa County, Grant County, Oklahoma

NWS Norman, OK issued this severe thunderstorm warning at Apr 26, 1999, 9:40 PM CDT for Alfalfa County, Grant County, Oklahoma. It was in force for 65 min. 2 reports came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued: Apr 26, 1999, 9:40 PM CDT (02:40 UTC)
Expired: Apr 26, 1999, 10:45 PM CDT
In force: 65 min
Issued by: NWS Norman, OK
Area: Whole counties

Counties Alfalfa County, OK, Grant County, OK

What was reported inside it

Time	Report	Where	Remark
Apr 26, 9:47 PM CDT	Hail 0.75	Byron, OK
Apr 26, 10:10 PM CDT	Hail 0.75	Medford, OK

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

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 26, 3:30 PM CDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Norman, OK (KOUN), launched 00:00Z, 2.7 hours before the alert went out and 181 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: 978 J/kg
Mixed-layer CIN: -22 J/kg
Mixed-layer LCL: 1097 m above ground
0-6 km bulk shear: 41 kt
0-1 km storm-relative helicity: 11 m²/s²
0-3 km storm-relative helicity: 70 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 1.1

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

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 Apr 26, 3:30 PM CDT, 6 hours 10 minutes earlier.

Area forecast discussion, Apr 26, 3:30 PM CDT, 6 hours 10 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORMAN OK
330 PM CDT MON APR 26 1999

MESONET INDICATES NUMEROUS BOUNDARIES OVER THE STATE WHICH WILL ACT
AS TRIGGERS FOR CONVECTIVE DEVELOPMENT THIS AFTERNOON INTO EARLY
EVENING. MAIN OUTFLOW BOUNDARY RUNS FROM FREEDOM TO TALOGA TO BINGER
THEN EAST TO NORMAN TO SEMINOLE. AIR TO THE NORTH AND EAST OF
BOUNDARY APPEARS TO HAVE RECOVERED LESS DURING THE DAY SINCE RAIN
OCCURRED INTO EARLY AFTERNOON OVER NORTH CENTRAL ZONES. A SECOND
BOUNDARY RUNS FROM CHICASHA TO DUNCAN TO WAURIKA WHICH HAS A WEAK
DRYLINE TYPE APPEARANCE. BEST CELLS APPEAR TO BE FIRING NEAR TRIPLE
POINT OF DRYLINE AND OUTFLOW BOUNDARY. FEEL ANY CONVECTION WILL
BRING MAINLY A HAIL THREAT WITH GUSTY WINDS A SECONDARY THREAT.
CELLS WILL DIMINISH AT SUNSET.

OTHERWISE...MODELS ARE FAIRLY SIMILAR IN SHORT TERM WITH MOVING
SURFACE LOW FROM OKLAHOMA SLOWLY INTO MISSOURI AND STALLING THERE.
SHORT WAVE RIDGE ALOFT BUILDS IN BEHIND CURRENT SHORTWAVE RESULTING
IN WEAK SURFACE RIDGING OVER THE STATE...MAKING FOR A SETTLED TWO
DAY PERIOD.

IN EXTENDED...MRF/CANADIAN/ECMWF KEEP NEXT CUTOFF JUST WEST WITH
HINT OF UPPER DIFLUENT/POSSIBLY DIVERGENT FLOW OVER OR JUST TO THE
WEST OF CWA. UNCERTAIN ABOUT HOW MUCH MOISTURE WILL BE AVAILABLE FOR
PRECIP IN THE EXTENDED SINCE MODELS INDICATE LARGE SURFACE HIGH WILL
TEND TO KEEP EAST TO SOUTHEAST RECYCLED FLOW IN LOWER LAYERS.  KEPT
A CHANCE OF PRECIP IN THE EXTENDED EACH DAY. WITH LITTLE TEMPERATURE
CHANGE.

33 / D FLOYD

.OUN...
OK...NONE
TX...NONE.

In the hours before

Local storm report, Apr 26, 7:46 PM CDT, 1 hour 54 minutes before

LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
746 PM CDT MON APR 26 1999

TIME (CDT) .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0741 PM    4 S WATONGA               OK   .88 INCH HAIL
04/26/99   BLAINE

0740 PM    GEARY                     OK   .75 INCH HAIL
04/26/99   BLAINE

0750 PM    4 NE GEARY                OK   .88 INCH HAIL
04/26/99   BLAINE

J

Local storm report, Apr 26, 7:46 PM CDT, 1 hour 54 minutes before

LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
746 PM CDT MON APR 26 1999

TIME (CDT) .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0741 PM    4 S WATONGA               OK   .88 INCH HAIL
04/26/99   BLAINE

0740 PM    GEARY                     OK   .75 INCH HAIL
04/26/99   BLAINE

0750 PM    4 NE GEARY                OK   .88 INCH HAIL
04/26/99   BLAINE

J

Local storm report, Apr 26, 8:17 PM CDT, 1 hour 23 minutes before

LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
817 PM CDT MON APR 26 1999

TIME (CDT) .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0755 PM    4 NE GEARY                OK   1.00 INCH HAIL
04/26/99   BLAINE

J

Local storm report, Apr 26, 8:17 PM CDT, 1 hour 23 minutes before

LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
817 PM CDT MON APR 26 1999

TIME (CDT) .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0755 PM    4 NE GEARY                OK   1.00 INCH HAIL
04/26/99   BLAINE

J

Local storm report, Apr 26, 8:25 PM CDT, 1 hour 15 minutes before

LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
825 PM CDT MON APR 26 1999

TIME (CDT) .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0802 PM    4 N HINTON                OK   1.75 INCH HAIL
04/26/99   CADDO

0827 PM    6 E NILES                 OK   1.00 INCH HAIL
04/26/99   CANADIAN

J

Local storm report, Apr 26, 8:25 PM CDT, 1 hour 15 minutes before

LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
825 PM CDT MON APR 26 1999

TIME (CDT) .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0802 PM    4 N HINTON                OK   1.75 INCH HAIL
04/26/99   CADDO

0827 PM    6 E NILES                 OK   1.00 INCH HAIL
04/26/99   CANADIAN

J

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 26, 7:04 PM CDT	Severe Thunderstorm Warning	OUN	Blaine	46 min
Apr 26, 7:30 PM CDT	Severe Thunderstorm Warning	OUN	Canadian, Kingfisher	45 min
Apr 26, 7:53 PM CDT	Severe Thunderstorm Warning	OUN	Blaine	37 min
Apr 26, 8:03 PM CDT	Tornado Warning	OUN	Caddo, Canadian	32 min
Apr 26, 8:31 PM CDT	Tornado Warning	OUN	Caddo, Canadian	29 min
Apr 26, 8:44 PM CDT	Severe Thunderstorm Warning	OUN	Grady	46 min
Apr 26, 8:51 PM CDT	Severe Thunderstorm Warning	OUN	Alfalfa	39 min
Apr 26, 8:58 PM CDT	Tornado Warning	OUN	Caddo	32 min
Apr 26, 9:22 PM CDT	Severe Thunderstorm Warning	OUN	Grady	33 min
Apr 26, 9:53 PM CDT	Severe Thunderstorm Warning	OUN	Grady, Stephens	57 min

Nearby

Severe Thunderstorm Warnings in Oklahoma, 1999 Every severe thunderstorm warning in 1999

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.