Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 73, NWS Tulsa, OK

April 15, 2001Osage County, Pawnee County, Tulsa County, Oklahoma

NWS Tulsa, OK issued this severe thunderstorm warning at Apr 15, 2001, 12:58 AM CDT for Osage County, Pawnee County, Tulsa County, Oklahoma. It was in force for 47 min. 5 reports came from 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, with what was reported inside it.

The facts

Issued: Apr 15, 2001, 12:58 AM CDT (05:58 UTC)
Expired: Apr 15, 2001, 1:45 AM CDT
In force: 47 min
Issued by: NWS Tulsa, OK
Area: Whole counties; the outline is the Mesonet’s reconstruction

Counties Osage County, OK, Pawnee County, OK, Tulsa County, OK

The radar

The Tulsa radar (KINX), 70 km from the middle of the area, began a volume at 06:01 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.

What was reported inside it

Time	Report	Where
Apr 15, 1:00 AM CDT	Hail 0.75	Barnsdall, OK
Apr 15, 1:20 AM CDT	Hail 0.75	Hallett, OK
Apr 15, 1:22 AM CDT	Hail 0.75	Collinsville, OK
Apr 15, 1:33 AM CDT	Hail 0.75	Owasso, OK
Apr 15, 1:43 AM CDT	Hail 0.75	Mannford, 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 14, 10:00 PM CDT	Tornado Watch	SPC	5 hr

The nearest sounding before it

Lamont, OK (KLMN), launched 00:00Z, 6.0 hours before the alert went out and 110 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: 1143 J/kg
Mixed-layer CIN: -134 J/kg
Mixed-layer LCL: 636 m above ground
0-6 km bulk shear: 74 kt
0-1 km storm-relative helicity: 247 m²/s²
0-3 km storm-relative helicity: 327 m²/s²
Significant tornado parameter: 0.9
Supercell composite: 10.5

Open this sounding in Storm Lab

The text

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

000 
WUUS54 KTSA 150559
SVRTUL
OKC113-117-143-150645-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TULSA OK
1258 AM CDT SUN APR 15 2001

THE NATIONAL WEATHER SERVICE IN TULSA HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN OSAGE COUNTY IN NORTHEAST OKLAHOMA
  PAWNEE COUNTY IN NORTHEAST OKLAHOMA
  NORTHERN TULSA COUNTY IN NORTHEAST OKLAHOMA

* UNTIL 145 AM CDT

* AT 1258 AM CDT...DOPPLER RADAR INDICATED SEVERE THUNDERSTORMS ALONG
  A LINE EXTENDING FROM 4 MILES EAST OF BARNSDALL TO 4 MILES SOUTH OF
  RALSTON...MOVING SOUTHEAST AT 30 MPH.

* SOME LOCATIONS NEAR THE PATH OF THESE STORMS INCLUDE...WESTPORT...
  RALSTON...CLEVELAND...SKEDEE...BLACKBURN...MARAMEC...HALLETT...
  TERLTON...JENNINGS...SKIATOOK...SPERRY...OWASSO...BARNSDALL...
  WYNONA...AVANT...HOMINY AND OSAGE.

HAIL TO THE SIZE OF NICKELS AND WIND GUSTS TO 60 MPH CAN BE
EXPECTED IN THE WARNED AREA.

A TORNADO WATCH IS ALSO IN EFFECT. TORNADOES CAN DEVELOP SUDDENLY
FROM SEVERE THUNDERSTORMS. BE ALERT FOR RAPIDLY CHANGING WEATHER
CONDITIONS.

LAT...LON 3668 9603 3650 9689 3612 9664 3618 9578

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 Apr 14, 9:50 PM CDT, 3 hours 8 minutes earlier.

Area forecast discussion, Apr 14, 9:50 PM CDT, 3 hours 8 minutes before

EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TULSA OK
950 PM CDT SAT APR 14 2001

THE QUESTION STILL REMAINS HOW FAR SOUTH WILL THE STORM COMPLEX GO?
ONE ISOLATED SUPERCELL HAS BEEN MOVING SLIGHTLY SOUTH OF EAST ACROSS
SOUTHERN KANSAS ALL EVENING...WHILE A CLUSTER OF STORMS HAS RECENTLY
DEVELOPED TO THE WEST OF THIS STORM.  IT STILL APPEARS THAT MOST OF
NORTHEAST OKLAHOMA MAY BE SPARED...BUT AREAS NEAR THE KANSAS BORDER
WILL PROBABLY FEEL THE HEAT IN THE NEXT FEW HOURS.  THE 00Z MESOETA
KEEPS MOST OF THE PRECIPITATION ALONG AND NORTH OF THE KANSAS BORDER
THROUGH 6Z AND THEN BACK BUILDS IT INTO A MORE WESTERLY LOW-LEVEL
JET ACROSS FAR NORTHEAST OKLAHOMA AND EVENTUALLY NORTHWEST
ARKANSAS.  THIS SCENARIO IS IN LINE WITH 18Z RUN AND IN GENERAL
MAKES SENSE.  WILL THEREFORE INCREASE POPS TO CATEGORICAL IN THE
NORTHEAST ZONES AND TAPER THEM TO CHANCE NEAR THE RED RIVER. A FEW
SHOWERS REMAIN NEAR THE RED RIVER AT THIS TIME...BUT MOST OF
ACTIVITY HAS MOVED EAST OF THAT AREA.

UPDATED ZONES WILL BE SENT AROUND 10 PM SO THAT WATCH HEADLINES CAN
BE CHANGED APPROPRIATELY.  THE WATCH IN SOUTHEAST OKLAHOMA WILL
EXPIRE ANDl A NEW WATCH FOR NORTHEAST OKLAHOMA AND NORTHWEST ARKANSAS
WILL BEGIN AT THAT TIME.

FCSTID = 19

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

In the hours before

Local storm report, Apr 14, 10:35 PM CDT, 2 hours 23 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
1035 PM CDT SAT APR 14 2001

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

0748 PM    2 W ANTLERS               OK    .75 INCH HAIL
04/14/01   PUSHMATAHA                      [ANTLERS PD]

0800 PM    HUGO                      OK    .75 INCH HAIL
04/14/01   CHOCTA8W                         [HUGO PD]

Local storm report, Apr 15, 12:44 AM CDT, 14 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
1245AM CDT SUN APR 15 2001

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

123w9 AM    1 N FAIRFAX               OK    .88 INCH HAIL
04/15/01   OSAGE                           SPOTTER REPORT

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 14, 7:20 PM CDT	Severe Thunderstorm Warning	TSA	Choctaw, Pushmataha	70 min
Apr 14, 11:37 PM CDT	Severe Thunderstorm Warning	TSA	Osage	38 min
Apr 15, 12:11 AM CDT	Severe Thunderstorm Warning	TSA	Nowata, Washington	49 min
Apr 15, 12:11 AM CDT	Severe Thunderstorm Warning	TSA	Osage, Pawnee	49 min
Apr 15, 1:27 AM CDT	Severe Thunderstorm Warning	TSA	Delaware, Mayes, Rogers	48 min
Apr 15, 1:27 AM CDT	Severe Thunderstorm Warning	TSA	Tulsa	48 min
Apr 15, 1:40 AM CDT	Severe Thunderstorm Warning	TSA	Creek	50 min
Apr 15, 2:05 AM CDT	Severe Thunderstorm Warning	TSA	Adair, Cherokee	40 min
Apr 15, 2:05 AM CDT	Severe Thunderstorm Warning	TSA	Wagoner	40 min
Apr 15, 2:28 AM CDT	Severe Thunderstorm Warning	TSA	Muskogee	47 min
Apr 15, 3:03 AM CDT	Severe Thunderstorm Warning	TSA	Sequoyah	57 min
Apr 15, 3:54 AM CDT	Severe Thunderstorm Warning	TSA	LeFlore	66 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.