Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 313, NWS Tulsa, OK

August 9, 2001LeFlore County, Oklahoma

NWS Tulsa, OK issued this severe thunderstorm warning at Aug 9, 2001, 6:20 PM CDT for LeFlore County, Oklahoma. It was in force for 25 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties.

The facts

Issued: Aug 9, 2001, 6:20 PM CDT (23:20 UTC)
Expired: Aug 9, 2001, 6:45 PM CDT
In force: 25 min
Issued by: NWS Tulsa, OK
Area: Whole counties; the outline is the Mesonet’s reconstruction

County LeFlore County, OK

The radar

The Western Arkansas radar (KSRX), 76 km from the middle of the area, began a volume at 23:20 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, 11.3 hours before the alert went out and 234 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: 238 J/kg
Mixed-layer CIN: -222 J/kg
Mixed-layer LCL: 1901 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: 173 m²/s²
0-3 km storm-relative helicity: 48 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

433 
WUUS54 KTSA 092321
SVRTUL
OKC079-092345-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TULSA OK
620 PM CDT THU AUG 9 2001

THE NATIONAL WEATHER SERVICE IN TULSA HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN LE FLORE COUNTY IN SOUTHEAST OKLAHOMA

* UNTIL 645 PM CDT

* AT 620 PM CDT...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM 9   
  MILES NORTHWEST OF WHITESBORO OR 4 MILES NORTHEAST OF 
  TALIHINA...MOVING SOUTHEAST AT 10 MPH.

* SOME LOCATIONS NEAR THE PATH OF THIS STORM INCLUDE...WHITESBORO AND
  MUSE.

HAIL TO THE SIZE OF DIMES AND WIND GUSTS TO 70 MPH CAN BE EXPECTED 
IN THE WARNED AREA.

LAT...LON 3485 9498 3474 9504 3460 9477 3478 9468

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 Tulsa, OK wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 9, 3:20 PM CDT, 3 hours earlier.

Area forecast discussion, Aug 9, 3:20 PM CDT, 3 hours before

EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TULSA OK
320 PM CDT THU AUG 9 2001

AREA 88D RADARS SHOWING ISOLATED CONVECTION AGAIN TODAY.  WILL NEED
TO CONTINUE THIS INTO THE EVENING IN SOME AREAS.  TEMPERATURES HAVE
WARMED NICELY AGAIN TODAY AS CU FIELD HAS REMAINED SMALLER THAN
YESTERDAY.  OVERNIGHT LOWS TONIGHT WILL BE SOMEWHAT OF A CHALLENGE
GIVEN POSITION OF FRONT TO OUR NORTH.  IF IT MAKES IT DOWN HERE LATE
TONIGHT...WE COULD SEE A LATE RALLY ON TEMPS DROPPING OFF ACROSS THE
NORTH.  IF THE FRONT HANGS UP NORTH A LITTLE LONGER...LOWS COULD BE
FAIRLY WARM AGAIN TONIGHT.

LOW CLOUDS SHOULD ACCOMPANY THE FRONT WHEN IT MAKES ITS APPEARANCE
IN OKLAHOMA ON FRIDAY.  AREAL EXTENT OF PRECIPITATION STILL REMAINS
IN QUESTION AS SURFACE FRONT MOVES INTO RIDGE.  WILL CONTINUE WITH
AT LEAST CURRENT POP FORECAST ACROSS THE AREA BUT MAY ADJUST WITHIN
THE CHANCE CATEGORY SOME.

EXTENDED STILL ON TRACK WITH PRECIP CHANCES INTO SUNDAY AS HIGH
BUILDS BACK OVER THE AREA.  MRF SHOWING RIDGE SHIFTING BACK TO THE
WEST DURING THE WEEK WHICH MAY EVENTUALLY PUT THE CWA IN NORTHWEST
FLOW.  WILL NEED TO MONITOR THIS PATTERN FOR POSSIBLE INCLUSION OF
PRECIPITATION ON THURSDAY.  OTHERWISE...NO BIG CHANGES PLANNED FOR
EXTENDED AT THIS TIME.

HOWIESON
FCSTID = 44

...PRELIMINARY NUMBERS...
TUL   77  92  68  90 /  20  30  30  20
FSM   77  93  68  91 /  20  30  30  20
MLC   78  96  70  92 /  20  30  30  30
BVO   74  88  66  89 /  30  30  30  20
FYV   73  88  66  87 /  20  40  30  20
BYV   73  88  66  87 /  20  40  30  20
MIO   74  87  66  88 /  30  40  30  20
MKO   77  92  68  90 /  20  30  30  20
F10   77  92  68  90 /  20  30  30  20
HHW   77  97  71  93 /  10  20  30  30

.TSA...
AR...NONE.
OK...NONE.

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 9, 6:45 PM CDT	Severe Thunderstorm Warning	TSA	LeFlore	45 min

Nearby

Severe Thunderstorm Warnings in Oklahoma, 2001 Every severe thunderstorm warning in 2001

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.