Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2000

Severe Thunderstorm Warning 329, NWS Norman, OK

June 21, 2000Major County, Woods County, Oklahoma

NWS Norman, OK issued this severe thunderstorm warning at Jun 21, 2000, 4:27 AM CDT for Major County, Woods 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: Jun 21, 2000, 4:27 AM CDT (09:27 UTC)
Expired: Jun 21, 2000, 5:15 AM CDT
In force: 48 min
Issued by: NWS Norman, OK
Area: Whole counties; the outline is the Mesonet’s reconstruction

Counties Major County, OK, Woods County, OK

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Jun 20, 11:00 PM CDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Dodge City, (KDDC), launched 00:00Z, 9.5 hours before the alert went out and 173 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: 101 J/kg
Mixed-layer CIN: -59 J/kg
Mixed-layer LCL: 2648 m above ground
0-6 km bulk shear: 31 kt
0-1 km storm-relative helicity: -10 m²/s²
0-3 km storm-relative helicity: 153 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.0

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 Jun 21, 4:25 AM CDT, 2 minutes earlier.

Area forecast discussion, Jun 21, 4:25 AM CDT, 2 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORMAN OK
425 AM CDT WED JUN 21 2000

MODEL GUIDANCE HAS NOT HANDLED FRONTAL MOVEMENT OR QPF OVER THE
FORECAST AREA VERY WELL THE LAST 2 DAYS...THUS WILL RELY HEAVILY ON
DIAGNOSTICS FOR THE NEXT 24 HOURS...THEN RELUCTANTLY ON MODELS
THEREAFTER.

MAIN FOCUS THIS MORNING IS EVENTUAL EFFECTS OF ONGOING CONVECTION
ACROSS NORTHWEST OKLAHOMA. WEAKER CAP...DEEPER MOISTURE...1000-500
MB DIFLUENCE AND AN OUTFLOW BOUNDARY TO ITS EAST ALL SUPPORT
CONTINUED DEVELOPMENT IN AN EAST-SOUTHEAST DIRECTION. HOWEVER EXCEPT
FOR ONE LARGE HP CELL OVER WOODWARD COUNTY...RADAR SHOWS
UNIMPRESSIVE AREAL COVERAGE OF HIGH RAINFALL RATES. FLASH FLOOD
GUIDANCE HAS ACTUALLY RISEN SINCE YESTERDAY...INDICATING IT WILL
TAKE 2 TO 4 INCHES OF RAIN IN 3 TO 6 HOURS TO CAUSE FLASH FLOODING.
EXCEPT FOR WHAT ACCOMPANIES THE CELL MENTIONED ABOVE...BELIEVE THE
PROBABILITY OF THIS OCCURRING IS TOO LOW TO WARRANT A WATCH AT THIS
TIME. IF TSRA EXPANDS MORE THAN EXPECTED OVER THE NEXT 1 TO 4
HOURS...WILL LIKELY ISSUE ANOTHER WATCH. IN THE MEANTIME WILL ISSUE
A FLASH FLOOD STATEMENT ADDRESSING CONCERNS.

TONIGHT'S FORECAST PARTIALLY HINGES UPON WHAT HAPPENS WITH THIS
OUTFLOW BOUNDARY LATE TODAY...AND WILL NEED TO KEEP SMALL POPS MOST
PLACES FOR THIS REASON ALONE. HOWEVER 00Z UPPER AIR ANALYSES SHOW
SMALL RIPPLES IN THE WESTERLY FLOW BETWEEN 700-500 MB ACROSS ARIZONA
AND NEW MEXICO...ANY OF WHICH MAY ACT AS A DESTABILIZER LATE TODAY
OR TONIGHT ACROSS THE FORECAST AREA. THE MOST NOTICEABLE ONE SHOWS
UP WELL ON WATER VAPOR IMAGERY NEAR THE ARIZONA/NEW MEXICO/AND
MEXICO BORDER. ANOTHER FACTOR MAY BE MOIST UPSLOPE FLOW INTO THE
HIGHER TERRAIN OF THE HIGH PLAINS OF COLORADO...AND THE
OKLAHOMA/TEXAS PANHANDLES WHICH MAY ACT AS A LIFTING MECHANISM. PLAN
TO KEEP POPS AROUND 40 PERCENT TONIGHT ACROSS WESTERN OKLAHOMA AND
WESTERN NORTH TEXAS...AND WILL JUST NEED TO MONITOR THROUGH THE DAY
FOR POTENTIAL ADJUSTMENTS.

CONVECTION MAY LINGER INTO PARTS OF THURSDAY...HOWEVER MODEL TRENDS
DO INDICATE A NORTHWARD RETREAT OF THE UPPER LEVEL TROUGH CURRENTLY
OVER THE CENTRAL UNITED STATES. IF THIS VERIFIES...GRADUAL
SUPPRESSION OF CONVECTIVE ACTIVITY SHOULD BE REALIZED TOWARD THE
WEEKEND AS SUBSIDENCE OCCURS MORE OFTEN AND CAP STRENGTHENS.
PREVIOUS FORECAST PACKAGE HANDLES THIS TREND WELL...AND WILL KEEP IT
ABOUT THE SAME...THAT IS KEEPING 20 POPS FOR THE THURSDAY ALL AREAS
AND THEN DRY FOR THURSDAY NIGHT THROUGH SATURDAY. SMALL POPS STILL
APPEAR TO BE JUSTIFIED FOR SUNDAY AS ANOTHER WEAK COLD FRONT TRIES
TO MOVE INTO THE FORECAST AREA FROM THE NORTH.

OKC   86  70  89  70 /  60  30  20   0
HBR   89  70  90  70 /  30  30  20   0
SPS   89  70  90  70 /  30  30  20   0
GAG   82  65  89  68 /  80  40  20   0
PNC   82  67  88  70 /  60  20  20   0
DUA   89  70  89  70 /  40  20  20   0

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

In the hours before

Local storm report, Jun 21, 3:47 AM CDT, 40 minutes before

LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
347 AM CDT WED JUN 21 2000

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

0342 AM    10 N WOODWARD             OK   60 MPH WIND GUST
06/21/00   WOODWARD                       REPORTED BY WOODWARD CO
                                          S.O. ON WOODWARD/HARPER CO
                                          LINE

0342 AM    21 SE BUFFALO             OK   60 MPH WIND GUST
06/21/00   HARPER                         PREVIOUS REPORT ON
                                          WOODWARD/HARPER CO LINE

TL     /

Local storm report, Jun 21, 3:54 AM CDT, 33 minutes before

LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
354 AM CDT WED JUN 21 2000

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

0345 AM    WOODWARD                  OK   WIND DAMAGE
06/21/00   WOODWARD                       LARGE TREE LIMBS BLOWN
                                          DOWN. REPORTED BY WOODWARD
                                          CO S.O.  

TL

Local storm report, Jun 21, 4:10 AM CDT, 17 minutes before

LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NORMAN OK
410 AM CDT WED JUN 21 2000

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

0350 AM    2 WSW WOODWARD            OK   63 MPH WIND GUST
06/21/00   WOODWARD                       MEASURED BY OKLAHOMA
                                          MESONET

TL

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 21, 1:57 AM CDT	Severe Thunderstorm Warning	OUN	Harper	48 min
Jun 21, 2:44 AM CDT	Severe Thunderstorm Warning	OUN	Ellis, Harper	46 min
Jun 21, 3:26 AM CDT	Severe Thunderstorm Warning	OUN	Harper, Woods, Woodward	64 min
Jun 21, 6:39 AM CDT	Severe Thunderstorm Warning	OUN	Beckham, Roger Mills	51 min

Nearby

Severe Thunderstorm Warnings in Oklahoma, 2000 Every severe thunderstorm warning in 2000

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.