Alert archive / Oklahoma / Severe Thunderstorm Warnings in 1999

Severe Thunderstorm Warning 95, NWS Tulsa, OK

April 5, 1999Adair County, Sequoyah County, Oklahoma

NWS Tulsa, OK issued this severe thunderstorm warning at Apr 5, 1999, 10:51 AM CDT for Adair County, Sequoyah County, Oklahoma. It was in force for 39 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
Apr 5, 1999, 10:51 AM CDT (15:51 UTC)
Expired
Apr 5, 1999, 11:30 AM CDT
In force
39 min
Issued by
NWS Tulsa, OK
Area
Whole counties; the outline is the Mesonet’s reconstruction

Counties Adair County, OK, Sequoyah County, OK

The radar

The Western Arkansas radar (KSRX), 51 km from the middle of the area, began a volume at 15:53 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

Springfield, MO (KSGF), launched 12:00Z, 3.9 hours before the alert went out and 160 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 1999-04-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1 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 1999-04-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 455 square meters per square second.19395878Sfc1 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
1 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
780 m above ground
0-6 km bulk shear
55 kt
0-1 km storm-relative helicity
455 m²/s²
0-3 km storm-relative helicity
592 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.

999 
WUUS54 KTSA 051559
SVRTUL
OKC001-135-051630-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TULSA OK
1051 AM CDT MON APR 5 1999

THE NATIONAL WEATHER SERVICE IN TULSA HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  ADAIR COUNTY IN EAST CENTRAL OKLAHOMA
  SEQUOYAH COUNTY IN EAST CENTRAL OKLAHOMA

* UNTIL 1130 AM CDT

* AT 1051 AM CDT A SEVERE THUNDERSTORM WAS LOCATED 4 MILES SOUTHWEST
  OF BRUSHY...MOVING NORTHEAST AT 50 MPH.

* SOME LOCATIONS NEAR THE PATH OF THIS STORM INCLUDE...  MARBLE
  CITY...BRUSHY...BUNCH AND STILWELL

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

LAT...LON 3557 9486 3547 9474 3565 9447 3602 9454

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 5, 7:50 AM CDT, 3 hours 1 minute earlier.

Area forecast discussion, Apr 5, 7:50 AM CDT, 3 hours 1 minute before
EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TULSA OK
750 AM CDT MON APR 5 1999

WILL ISSUE UPDATE SHORTLY TO ACCOUNT FOR NEW WATCH BOX
CONFIGURATION. SPC SAYS THEY WILL MONITOR ACTIVITY FURTHER SOUTH AND
ISSUE WATCH LATER IF IT PERSISTS. ODDLY...INSTABILITY ANALYSIS SHOWS
A MINIMUM IN THE INSTABILITY AXIS WHERE THE CURRENT CONVECTION IS
THAT WE ARE WARNING ON. HOWEVER...SURFACE WINDS HAVE BACKED SLIGHTLY
IN ADVANCE OF THIS ACTIVITY IN THE PAST TWO HOURS...SO SURFACE
MOISTURE CONVERGENCE HAS INCREASED SOME. WITH DAYTIME HEATING...SOME
INTENSIFICATION IS POSSIBLE LATER THIS MORNING. HOWEVER WITH BEST
DYNAMIC LIFT IN KS/MO...BELIEVE ACTIVITY SOUTH OF NEW WATCH BOX WILL
SIMPLY MAINTAIN ITSELF FOR A COUPLE MORE HOURS.

FCSTID = 22

.TUL...
OK...TORNADO WATCH UNTIL 200 PM CDT FOR ZONES OKZ054>058.

AR...NONE.

In the hours before

Special weather statement, Apr 5, 6:05 AM CDT, 4 hours 46 minutes before
ARZ001-002-010-011-019-020-029-OKZ049-053>076-061200-

EASTERN OKLAHOMA/NORTHWEST ARKANSAS HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TULSA OK
605 AM CDT MON APR 5 1999

...A FEW SEVERE THUNDERSTORMS ARE POSSIBLE ACROSS EASTERN OKLAHOMA AND
NORTHWEST ARKANSAS THIS MORNING AND AFTERNOON...

.SYNOPSIS...
A STRONG UPPER LEVEL LOW PRESSURE SYSTEM OVER NORTHERN NEW MEXICO EARLY
THIS MORNING WILL LIFT INTO WESTERN KANSAS BY THIS AFTERNOON.
MEANWHILE...SURFACE LOW PRESSURE ACROSS NORTHWEST OKLAHOMA WILL MOVE
INTO NORTHEASTERN KANSAS...WITH A DRYLINE PUSHING INTO FAR EASTERN
OKLAHOMA THIS AFTERNOON.

.DISCUSSION...
THE AIRMASS ACROSS EASTERN OKLAHOMA REMAINS VERY MOIST AND UNSTABLE THIS
MORNING...WITH SURFACE DEWPOINTS IN THE LOWER TO MID 60S.  STRONG
SOUTHERLY TO SOUTHEASTERLY LOW-LEVEL WINDS WILL RESULT IN CONTINUED
STRONG LIFT ACROSS THE REGION.  AN INITIAL BAND OF SHOWERS AND A FEW
THUNDERSTORMS WILL MOVE ACROSS EASTERN OKLAHOMA EARLY THIS MORNING
BETWEEN 6 AM AND 9 AM....BUT THIS ACTIVITY SHOULD REMAIN BELOW SEVERE
LIMITS.

MEANWHILE...A SECONDARY LINE OF THUNDERSTORMS OVER SOUTH CENTRAL
OKLAHOMA EARLY THIS MORNING WILL CONTINUE TO MOVE QUICKLY NORTHEAST.
THESE THUNDERSTORMS SHOULD REMAIN STRONG TO SEVERE AS THE DRYLINE
PUNCHES INTO CENTRAL OKLAHOMA AND COOLER TEMPERATURES ALOFT SPREAD EAST.
THIS ACTIVITY SHOULD EVENTUALLY FORM INTO A BROKEN SQUALL LINE...AND
MOVE THROUGH EASTERN OKLAHOMA AFTER 9 AM AND EVENTUALLY REACH NORTHWEST
ARKANSAS AROUND 11 AM.  STRONG STRAIGHT-LINE WINDS WILL BE THE PRIMARY
SEVERE WEATHER THREAT.

THE SEVERE WEATHER THREAT SHOULD DIMINISH AFTER 2 TO 3 PM AS THE LINE OF
THUNDERSTORMS MOVES FARTHER EAST INTO ARKANSAS.

.EMERGENCY AGENCY AND SPOTTER ACTIVATION...
STORM SPOTTER ACTIVATION MAY BE NEEDED THIS MORNING ACROSS EASTERN
OKLAHOMA AND NORTHWEST ARKANSAS.

AN UPDATED HAZARDOUS WEATHER OUTLOOK WILL BE ISSUED AROUND 1 PM.
Special weather statement, Apr 5, 6:05 AM CDT, 4 hours 46 minutes before
ARZ001-002-010-011-019-020-029-OKZ049-053>076-061200-

EASTERN OKLAHOMA/NORTHWEST ARKANSAS HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TULSA OK
605 AM CDT MON APR 5 1999

...A FEW SEVERE THUNDERSTORMS ARE POSSIBLE ACROSS EASTERN OKLAHOMA AND
NORTHWEST ARKANSAS THIS MORNING AND AFTERNOON...

.SYNOPSIS...
A STRONG UPPER LEVEL LOW PRESSURE SYSTEM OVER NORTHERN NEW MEXICO EARLY
THIS MORNING WILL LIFT INTO WESTERN KANSAS BY THIS AFTERNOON.
MEANWHILE...SURFACE LOW PRESSURE ACROSS NORTHWEST OKLAHOMA WILL MOVE
INTO NORTHEASTERN KANSAS...WITH A DRYLINE PUSHING INTO FAR EASTERN
OKLAHOMA THIS AFTERNOON.

.DISCUSSION...
THE AIRMASS ACROSS EASTERN OKLAHOMA REMAINS VERY MOIST AND UNSTABLE THIS
MORNING...WITH SURFACE DEWPOINTS IN THE LOWER TO MID 60S.  STRONG
SOUTHERLY TO SOUTHEASTERLY LOW-LEVEL WINDS WILL RESULT IN CONTINUED
STRONG LIFT ACROSS THE REGION.  AN INITIAL BAND OF SHOWERS AND A FEW
THUNDERSTORMS WILL MOVE ACROSS EASTERN OKLAHOMA EARLY THIS MORNING
BETWEEN 6 AM AND 9 AM....BUT THIS ACTIVITY SHOULD REMAIN BELOW SEVERE
LIMITS.

MEANWHILE...A SECONDARY LINE OF THUNDERSTORMS OVER SOUTH CENTRAL
OKLAHOMA EARLY THIS MORNING WILL CONTINUE TO MOVE QUICKLY NORTHEAST.
THESE THUNDERSTORMS SHOULD REMAIN STRONG TO SEVERE AS THE DRYLINE
PUNCHES INTO CENTRAL OKLAHOMA AND COOLER TEMPERATURES ALOFT SPREAD EAST.
THIS ACTIVITY SHOULD EVENTUALLY FORM INTO A BROKEN SQUALL LINE...AND
MOVE THROUGH EASTERN OKLAHOMA AFTER 9 AM AND EVENTUALLY REACH NORTHWEST
ARKANSAS AROUND 11 AM.  STRONG STRAIGHT-LINE WINDS WILL BE THE PRIMARY
SEVERE WEATHER THREAT.

THE SEVERE WEATHER THREAT SHOULD DIMINISH AFTER 2 TO 3 PM AS THE LINE OF
THUNDERSTORMS MOVES FARTHER EAST INTO ARKANSAS.

.EMERGENCY AGENCY AND SPOTTER ACTIVATION...
STORM SPOTTER ACTIVATION MAY BE NEEDED THIS MORNING ACROSS EASTERN
OKLAHOMA AND NORTHWEST ARKANSAS.

AN UPDATED HAZARDOUS WEATHER OUTLOOK WILL BE ISSUED AROUND 1 PM.
Local storm report, Apr 5, 8:30 AM CDT, 2 hours 21 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
830 AM CDT MON APR 05 1999

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

0810 AM    WELEETKA                  OK   65 MPH TSTM GUST
04/05/99   OKFUSKEE                       REPORTED BY PUBLIC
                                          AT CITY POST OFFICE.
Local storm report, Apr 5, 8:45 AM CDT, 2 hours 6 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
845 AM CDT MON APR 05 1999

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

0825 AM    HENRYETTA                 OK   60 MPH TSTM GUST
04/05/99   OKMULGEE                       ESTIMATED BY HENRYETTA
                                          AIRPORT EMPLOYEES.
Special weather statement, Apr 5, 10:49 AM CDT, 2 minutes before
OKZ054>058-051649-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TULSA OK
1049 AM CDT MON APR 5 1999

THE TORNADO WATCH HAS BEEN CANCELLED FOR THE FOLLOWING COUNTIES IN

EASTERN OKLAHOMA.
         CRAIG               NOWATA              OSAGE
         OTTAWA              WASHINGTON

THE THREAT OF SEVERE WEATHER HAS MOVED TO THE EAST OF THE AREA.
Special weather statement, Apr 5, 10:49 AM CDT, 2 minutes before
OKZ054>058-051649-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TULSA OK
1049 AM CDT MON APR 5 1999

THE TORNADO WATCH HAS BEEN CANCELLED FOR THE FOLLOWING COUNTIES IN

EASTERN OKLAHOMA.
         CRAIG               NOWATA              OSAGE
         OTTAWA              WASHINGTON

THE THREAT OF SEVERE WEATHER HAS MOVED TO THE EAST OF THE AREA.

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 4, 7:10 PM CDTSevere Thunderstorm WarningTSAAdair, Sequoyah35 min
Apr 4, 7:42 PM CDTSevere Thunderstorm WarningTSAAdair33 min
Apr 5, 7:30 AM CDTSevere Thunderstorm WarningTSAOkfuskee45 min
Apr 5, 8:01 AM CDTSevere Thunderstorm WarningTSAMcIntosh, Okmulgee44 min

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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.