Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 240, NWS Tulsa, OK

July 28, 2002Nowata County, Washington County, Oklahoma

NWS Tulsa, OK issued this severe thunderstorm warning at Jul 28, 2002, 11:42 PM CDT for Nowata County, Washington County, Oklahoma. It was in force for 63 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jul 28, 2002, 11:42 PM CDT (04:42 UTC)
Expired
Jul 29, 2002, 12:45 AM CDT
In force
63 min
Issued by
NWS Tulsa, OK
Area
Counties, with a storm outline in the text

Counties Nowata County, OK, Washington County, OK

The radar

The Tulsa radar (KINX), 79 km from the middle of the area, began a volume at 04:42 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.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Lamont, OK (KLMN), launched 00:00Z, 4.7 hours before the alert went out and 155 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-pSkew-T log-p diagram, Lamont, OK at 00:00Z on 2002-07-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2257 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lamont, OK at 00:00Z on 2002-07-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 60 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
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
2257 J/kg
Mixed-layer CIN
-74 J/kg
Mixed-layer LCL
1318 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
60 m²/s²
0-3 km storm-relative helicity
153 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.3

Open this sounding in Storm Lab

The text

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

991 
WUUS54 KTSA 290442
SVRTUL
OKC105-147-290545-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TULSA OK
1141 PM CDT SUN JUL 28 2002

THE NATIONAL WEATHER SERVICE IN TULSA HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NOWATA COUNTY IN NORTHEAST OKLAHOMA
  WASHINGTON COUNTY IN NORTHEAST OKLAHOMA

* UNTIL 1245 AM CDT

* AT 1141 PM CDT...DOPPLER RADAR INDICATED SEVERE THUNDERSTORMS ALONG
  A LINE EXTENDING FROM 5 MILES NORTH OF COPAN TO 10 MILES WEST OF
  OCHELATA...MOVING EAST AT 50 MPH.

* SOME LOCATIONS NEAR THE PATH OF THESE STORMS INCLUDE...OCHELATA...
  DEWEY...COPAN...NOWATA...DELAWARE...LENAPAH...WANN...WATOVA...NEW
  ALLUWE AND BARTLESVILLE.

WIND GUSTS TO 60 MPH CAN BE EXPECTED IN THE WARNED AREA. STAY 
INDOORS AND AWAY FROM WINDOWS UNTIL THE STORM HAS PASSED.

LAT...LON 3707 9598 3659 9601 3660 9543 3700 9544

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 Jul 28, 9:30 PM CDT, 2 hours 12 minutes earlier.

Area forecast discussion, Jul 28, 9:30 PM CDT, 2 hours 12 minutes before
EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TULSA OKLAHOMA
930 PM CDT SUN JUL 28 2002

LINE OF STORMS THAT DEVELOPED ALONG COLD FRONT ARE SLOWLY PUSHING
EAST ACROSS KS AND NRN OK. ALTHOUGH SVR POTENTIAL MAY LESSEN ACROSS
ERN OK...A 20-30 KT LOW LEVEL JET IN PLACE ACROSS THE REGION WILL
HELP MAINTAIN STORM IDENTITY AS THEY PROGRESS TOWARDS NERN OK LATE
TONIGHT.  CURRENT POPS FORECAST LOOKS GOOD WITH HIGHEST POPS ACROSS
NERN OK.  WILL NOT ISSUE UPDATED ZFP...THOUGH THICK MID LEVEL/HIGH
CLOUDS HAVE KEPT TEMPS UP THIS EVENING...SO WILL GO AHEAD AND UPDATE
RDF TEMP TRENDS.

FORECAST ID = 23

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

In the hours before

Special weather statement, Jul 28, 10:34 PM CDT, 1 hour 8 minutes before
ARZ001-002-010-011-019-020-029-OKZ049-053>076-291200-

EASTERN OKLAHOMA/NORTHWEST ARKANSAS HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TULSA OK
1034 PM CDT SUN JUL 28 2002

...UPDATED FOR EVENING TRENDS...

A LINE OF THUNDERSTORMS HAS DEVELOPED THIS EVENING FROM KANSAS DOWN
INTO NORTH CENTRAL AND NORTHWEST OKLAHOMA.  THESE STORMS ARE MOVING
TO THE SOUTH AND SOUTHEAST AT 40 TO 50 MILES AN HOUR AND WILL BE
CAPABLE OF PRODUCING HEAVY RAIN AND STRONG GUSTY WINDS INTO THE
EARLY MORNING HOURS AS THEY MOVE INTO NORTHEAST OKLAHOMA.

WINDS OF 50 TO 60 MILES AN HOUR OR GREATER WILL BE POSSIBLE ALONG
THE LEADING EDGE OF THE STORMS.  THE STORMS ARE EXPECTED TO WEAKEN
WITH TIME AFTER MIDNIGHT.

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 28, 10:36 PM CDTSevere Thunderstorm WarningTSAOsage, Pawnee54 min
Jul 28, 11:26 PM CDTSevere Thunderstorm WarningTSAOsage49 min

Nearby

Severe Thunderstorm Warnings in Oklahoma, 2002Every severe thunderstorm warning in 2002

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.