Alert archive / Oklahoma / Severe Thunderstorm Warnings in 1999

Severe Thunderstorm Warning 413, NWS Tulsa, OK

July 7, 1999Cherokee County, Oklahoma

NWS Tulsa, OK issued this severe thunderstorm warning at Jul 7, 1999, 1:53 PM CDT for Cherokee County, Oklahoma. It was in force for 52 min. 1 report 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
Jul 7, 1999, 1:53 PM CDT (18:53 UTC)
Expired
Jul 7, 1999, 2:45 PM CDT
In force
52 min
Issued by
NWS Tulsa, OK
Area
Whole counties; the outline is the Mesonet’s reconstruction

County Cherokee County, OK

The radar

The Tulsa radar (KINX), 52 km from the middle of the area, began a volume at 18:56 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

TimeReportWhereRemark
Jul 7, 2:15 PM CDTThunderstorm WindPeggs, OKA power line was blown down near Peggs.

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 nearest sounding before it

Springfield, MO (KSGF), launched 12:00Z, 6.9 hours before the alert went out and 151 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, Springfield, MO at 12:00Z on 1999-07-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1053 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, Springfield, MO at 12:00Z on 1999-07-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 20 square meters per square second.1939Sfc1 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
1053 J/kg
Mixed-layer CIN
-76 J/kg
Mixed-layer LCL
748 m above ground
0-6 km bulk shear
6 kt
0-1 km storm-relative helicity
20 m²/s²
0-3 km storm-relative helicity
35 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.

000 
TTAA00 KTUL 071855 RRA
SVRTUL
OKC021-071945-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TULSA OK
153 PM CDT WED JUL 7 1999

THE NATIONAL WEATHER SERVICE IN TULSA HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CHEROKEE COUNTY IN EAST CENTRAL OKLAHOMA

* UNTIL 245 PM CDT

* AT 153 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED  
A SEVERE THUNDERSTORM NEAR TAHLEQUAH...MOVING NORTH AT 10   MPH.

* SOME LOCATIONS NEAR THE PATH OF THIS STORM 
INCLUDE...MOODYS...PEGGS AND   TAHLEQUAH

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

LAT...LON 3585 9508 3590 9487 3621 9497 3609 9520

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 7, 11:02 AM CDT, 2 hours 51 minutes earlier.

Area forecast discussion, Jul 7, 11:02 AM CDT, 2 hours 51 minutes before
EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TULSA OK
1102 AM CDT WED JUL 7 1999

WEAK COLD FRONT TO THE NORTH HAS STALLED FROM WESTERN KENTUCKY...ACROSS
EXTREME SOUTHERN MISSOURI AND INTO SOUTHEAST KANSAS.  THE FRONT
SHOULD MOVE LITTLE THE REST OF TODAY.

MORNING SOUNDINGS AROUND THE AREA SHOW THAT THE CONVECTIVE
TEMPERATURE WILL BE REACHED AGAIN THIS AFTERNOON...SO THAT ISOLATED
SHOWERS AND THUNDERSTORMS WILL OCCUR AGAIN TODAY...WITH THE MOST
NUMEROUS CELLS IN THE HIGHER TERRAIN IN SOUTHEAST OKLAHOMA AND
WESTERN ARKANSAS.  IN ADDITION...MOISTURE CONVERGENCE WAS OCCURRING
ALONG THE STALLED FRONT AT MID MORNING NEAR THE MISSOURI AND
ARKANSAS BORDERS AND THIS FRONT WILL LIKELY ALSO BE THE FOCUS FOR
ISOLATED DEVELOPMENT.  IT WAS NOTED TODAY THAT LOW-LEVEL MOISTURE
WAS A LITTLE DEEPER THAN 24 HOURS AGO...RESULTING IN FORECAST CAPES
AROUND 2000 J/KG LATER TODAY.  WITH A SLIGHTLY LOWER WET-BULB ZERO
TODAY A STORM OR TWO COULD BRIEFLY PULSE TO NEAR SEVERE LEVELS.

TEMPERATURES TODAY ARE AVERAGING OUT ABOUT AS YESTERDAY...EXCEPT IN
FAR NORTHEAST SECTIONS OF THE FORECAST AREA...HARRISON AR IS RUNNING
5 DEGREES OFF YESTERDAYS PACE.

ALL OF THIS COVERED IN THE GOING FORECAST AND WILL NOT MAKE ANY
CHANGES TO THE ZONES AT THIS TIME.

FCSTID = 8

.TUL...
AR...NONE.
OK...NONE.

In the hours before

Special weather statement, Jul 7, 12:50 PM CDT, 1 hour 3 minutes before
ARZ001-002-010-011-019-020-029-OKZ049-053>076-081100-

EASTERN OKLAHOMA/NORTHWEST ARKANSAS HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TULSA OK
1250 PM CDT WED JUL 7 1999

ISOLATED SEVERE THUNDERSTORMS ARE EXPECTED THIS AFTERNOON AND EARLY THIS
EVENING.

.SYNOPSIS...
HIGH PRESSURE ALOFT WILL REMAIN ANCHORED OVER THE CENTRAL PART OF THE
NATION THROUGH TONIGHT.

.DISCUSSION...
STRONG SURFACE HEATING HAS RESULTED IN A MODERATELY UNSTABLE AIR MASS
ACROSS EASTERN OKLAHOMA AND NORTHWEST ARKANSAS.  THIS COMBINED WITH A
WEAK CAP WILL ALLOW WIDELY SCATTERED SHOWERS AND THUNDERSTORMS TO OCCUR
ACROSS THE AREA THIS AFTERNOON AND EVENING.  GIVEN THE AMOUNT OF
INSTABILITY AND WEAK WINDS ALOFT A STORM OR TWO MAY BRIEFLY BECOME
SEVERE WITH LARGE HAIL AND STRONG GUSTY WINDS.  LOCALLY HEAVY RAINS WILL
ALSO BE POSSIBLE.

.EMERGENCY MANAGEMENT AGENCY AND SPOTTER ACTIVATION...
STORM SPOTTER ACTIVATION IS NOT ANTICIPATED DUE TO THE BRIEF NATURE THE
SEVERE WEATHER EXPECTED THIS AFTERNOON AND EVENING.
Special weather statement, Jul 7, 12:50 PM CDT, 1 hour 3 minutes before
ARZ001-002-010-011-019-020-029-OKZ049-053>076-081100-

EASTERN OKLAHOMA/NORTHWEST ARKANSAS HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TULSA OK
1250 PM CDT WED JUL 7 1999

ISOLATED SEVERE THUNDERSTORMS ARE EXPECTED THIS AFTERNOON AND EARLY THIS
EVENING.

.SYNOPSIS...
HIGH PRESSURE ALOFT WILL REMAIN ANCHORED OVER THE CENTRAL PART OF THE
NATION THROUGH TONIGHT.

.DISCUSSION...
STRONG SURFACE HEATING HAS RESULTED IN A MODERATELY UNSTABLE AIR MASS
ACROSS EASTERN OKLAHOMA AND NORTHWEST ARKANSAS.  THIS COMBINED WITH A
WEAK CAP WILL ALLOW WIDELY SCATTERED SHOWERS AND THUNDERSTORMS TO OCCUR
ACROSS THE AREA THIS AFTERNOON AND EVENING.  GIVEN THE AMOUNT OF
INSTABILITY AND WEAK WINDS ALOFT A STORM OR TWO MAY BRIEFLY BECOME
SEVERE WITH LARGE HAIL AND STRONG GUSTY WINDS.  LOCALLY HEAVY RAINS WILL
ALSO BE POSSIBLE.

.EMERGENCY MANAGEMENT AGENCY AND SPOTTER ACTIVATION...
STORM SPOTTER ACTIVATION IS NOT ANTICIPATED DUE TO THE BRIEF NATURE THE
SEVERE WEATHER EXPECTED THIS AFTERNOON AND EVENING.

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 7, 12:32 PM CDTSevere Thunderstorm WarningTSASequoyah43 min
Jul 7, 2:48 PM CDTSevere Thunderstorm WarningTSAMayes, Rogers42 min
Jul 7, 3:08 PM CDTFlash Flood WarningTSAMayes, Rogers2 hr

Nearby

Severe Thunderstorm Warnings in Oklahoma, 1999Every 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; radar from the NEXRAD Level II archive.