Alert archive / Oklahoma / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 221, NWS Tulsa, OK

May 15, 1998Osage County, Washington County, Oklahoma

NWS Tulsa, OK issued this severe thunderstorm warning at May 15, 1998, 7:38 AM CDT for Osage County, Washington County, Oklahoma. It was in force for 37 min. 2 reports came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
May 15, 1998, 7:38 AM CDT (12:38 UTC)
Expired
May 15, 1998, 8:15 AM CDT
In force
37 min
Issued by
NWS Tulsa, OK
Area
Whole counties

Counties Osage County, OK, Washington County, OK

The radar

The Tulsa radar (KINX), 76 km from the middle of the area, began a volume at 12:41 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
May 15, 7:45 AM CDTHail 0.75Bowring, OK
May 15, 7:55 AM CDTHail 0.75Copan, 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.

IssuedProductOfficeLasted
May 15, 5:50 AM CDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Norman, OK (KOUN), launched 12:00Z, 0.6 hours before the alert went out and 197 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, Norman, OK at 12:00Z on 1998-05-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Norman, OK at 12:00Z on 1998-05-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -142 square meters per square second.1939587897117Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1890 m above ground
0-6 km bulk shear
64 kt
0-1 km storm-relative helicity
-142 m²/s²
0-3 km storm-relative helicity
43 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.3

Open this sounding in Storm Lab

The text

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

788 
WUUS54 KTSA 151239 RRA
SVRTUL
OKC113-147-151315-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TULSA OK
738 AM CDT FRI MAY 15 1998

THE NATIONAL WEATHER SERVICE IN TULSA HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...

  NORTHEASTERN OSAGE COUNTY IN NORTHEASTERN OKLAHOMA
  NORTHERN WASHINGTON COUNTY IN NORTHEASTERN OKLAHOMA

* UNTIL 815 AM CDT

* AT 732 AM...NATIONAL WEATHER SERVICE DOPPLER RADAR DETECTED A
  SEVERE THUNDERSTORM 10 MILES SOUTHWEST OF COPAN...MOVING NORTHEAST
  AT 55 MPH.

* SOME LOCATIONS AFFECTED INCLUDE...
  COPAN
  HULAH

  HAIL TO THE SIZE OF NICKELS AND WIND GUSTS TO 65 MPH CAN BE
  EXPECTED IN THE WARNED AREA.



BE ALERT TO RAPIDLY CHANGING WEATHER CONDITIONS AS STORMS APPROACH.

WHEN THUNDERSTORMS APPROACH...TAKE COVER INSIDE A STURDY BUILDING.
STAY AWAY FROM WINDOWS. TO PROTECT YOURSELF FROM LIGHTNING STAY OFF
THE PHONE AND DONT USE HAND HELD ELECTRICAL APPLIANCES. MOTORISTS
SHOULD NEVER DRIVE INTO AREAS WHERE WATER COVERS THE ROAD.

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 May 15, 3:50 AM CDT, 3 hours 48 minutes earlier.

Area forecast discussion, May 15, 3:50 AM CDT, 3 hours 48 minutes before
FPUS3 KTUL 150851
AFDTUL

EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TULSA OK
350 AM CDT FRI MAY 15 1998

VIGOROUS SHORWAVE TO MOVE TO OUR WEST AND NORTH TODAY.  SHORTWAVE HAS
HELPED TO TRIGGER A LINE OF THUNDERSTORMS ALONG DRY LINE/PACIFIC COLD
FRONT IN THE TEXAS PANHANDLE AND WESTERN OKLAHOMA THIS MORNING.
EXPECT STORMS TO CONTINUE TO MOVE EAST NORTHEAST AND EVENTUALLY
EFFECT THE FORECAST AREA.  HAVE GONE LIKELY POPS NORHEAST OKLAHOMA
AND NORTHWEST ARKANSAS AND GOOD CHANCE POPS FOR AREAS TO THE SOUTH.
MAIN CHANCE FOR RAIN TO BE THIS MORNING...BUT WILL NOT GET CUTE WITH
WORDING AS DRY LINE/PACIFIC COLD FRONT TO MAKE ITS WAY ACROSS THE
AREA LATER TODAY AND COULD TRIGGER ADDITIONAL SHOWERS AND
THUNDERSTORMS.  HAVE KEPT SLIGHT CHANCE POPS IN FOR THE EASTERN ZONES
THIS EVENING FOR THIS REASON AS WELL.

TEMPERATURE WISE HAVE BASICALLY FOLLOWED THE FWC NUMBERS WITH ONLY A
FEW SLIGHT VARIATIONS.  TONIGHT TO BE COOLER THAN THIS MORNING DUE TO
LOWER DEW POINTS AND LESS WIND...BUT HIGHS SHOULD STAY IN THE 80S AS
COOLING BEHIND FRONT IS NOT SIGNIFICANT.

LOOKING AHEAD IT APPEARS THE REMAINDER OF THE FORECAST PERIOD WILL BE
QUIET AND WARM AS AN UPPER RIDGE BUILDS OVER THE AREA AND REMAINS IN
PLACE.

FCSTID = 17
TUL   87  60  88  65 /  60  10   0   0
FSM   87  60  88  59 /  50  20   0   0
MLC   87  62  89  63 /  50  10   0   0
BVO   86  58  87  63 /  60  10   0   0
FYV   85  57  85  56 /  60  20   0   0
IDB   87  61  89  62 /  40  20   0   0
BYV   84  56  84  55 /  60  20   0   0
MIO   86  58  86  60 /  60  10   0   0
MKO   87  60  88  65 /  60  10   0   0
F10   87  61  88  64 /  60  10   0   0
HHW   87  62  89  63 /  40  20   0   0

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

ABBAS

In the hours before

Special weather statement, May 15, 6:00 AM CDT, 1 hour 38 minutes before
ARZ001-002-010-011-019-020-029-OKZ049-053>076-161200-

EASTERN OKLAHOMA/NORTHWEST ARKANSAS HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TULSA OK
600 AM CDT FRI MAY 15 1998

STRONG TO SEVERE THUNDERSTORMS WILL MOVE ACROSS NORTHEAST OKLAHOMA THIS
MORNING...MAINLY TO THE NORTH AND WEST OF I-44.  ISOLATED SEVERE
THUNDERSTORMS ARE ALSO POSSIBLE OVER THE REMAINDER OF EASTERN OKLAHOMA
AND NORTHWEST ARKANSAS THIS MORNING.

A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR OSAGE AND PAWNEE COUNTIES
UNTIL 8 AM.

A LINE OF STRONG TO SEVERE THUNDERSTORMS THAT DEVELOPED OVER THE TEXAS
PANHANDLE AROUND MIDNIGHT HAS BEEN RACING EASTWARD ACROSS OKLAHOMA
DURING THE NIGHT.  THE STORMS WILL MOVE RAPIDLY ACROSS EASTERN OKLAHOMA
AND NORTHWEST ARKANSAS THIS MORNING...BEFORE MOVING OFF TO THE EAST BY
LATE THIS MORNING OR EARLY THIS AFTERNOON.

THE STORMS ARE THE RESULT OF A STRONG UPPER LEVEL SYSTEM MOVING
NORTHEASTWARD FROM NEW MEXICO TOWARD THE CENTRAL PLAINS INTERACTING WITH
A DRYLINE AND PACIFIC COLD FRONT AT THE SURFACE OFF TO THE WEST.  WITH
A VERY UNSTABLE ATMOSPHERE AHEAD OF THESE SYSTEMS THE STORMS ARE
EXPECTED TO REMAIN STRONG TO SEVERE AS THEY MOVE ACROSS THE AREA.  THE
GREATEST THREAT WILL BE ACROSS NORTHEAST OKLAHOMA...CLOSER TO THE UPPER
SYSTEM...BUT AN ISOLATED SEVERE THUNDERSTORM OR TWO WITHIN THE LINE MAY
ALSO OCCUR ACROSS SOUTHEAST OKLAHOMA AND NORTHWEST ARKANSAS.  STRONG
DAMAGING WINDS ARE EXPECTED TO BE THE PRIMARY THREAT...BUT LARGE HAIL
MAY ALSO ACCOMPANY A FEW OF THE STORMS.

WITH THE UPPER SYSTEM PULLING AWAY...AND THE RAPID MOVEMENT OF THE
LINE...THE THREAT OF SEVERE WEATHER IS EXPECTED TO END BY AROUND MIDDAY
AS THE STORMS RACE OFF TO THE EAST ACROSS ARKANSAS AND MISSOURI AND
WEAKEN.

CIVIL DEFENSE ORGANIZATIONS AND SPOTTER GROUPS SHOULD EXPECT TO BE
ACTIVATED THIS MORNING IF NOT ALREADY ACTIVATED...ESPECIALLY OVER
NORTHEAST OKLAHOMA.
Special weather statement, May 15, 6:00 AM CDT, 1 hour 38 minutes before
ARZ001-002-010-011-019-020-029-OKZ049-053>076-161200-

EASTERN OKLAHOMA/NORTHWEST ARKANSAS HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TULSA OK
600 AM CDT FRI MAY 15 1998

STRONG TO SEVERE THUNDERSTORMS WILL MOVE ACROSS NORTHEAST OKLAHOMA THIS
MORNING...MAINLY TO THE NORTH AND WEST OF I-44.  ISOLATED SEVERE
THUNDERSTORMS ARE ALSO POSSIBLE OVER THE REMAINDER OF EASTERN OKLAHOMA
AND NORTHWEST ARKANSAS THIS MORNING.

A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR OSAGE AND PAWNEE COUNTIES
UNTIL 8 AM.

A LINE OF STRONG TO SEVERE THUNDERSTORMS THAT DEVELOPED OVER THE TEXAS
PANHANDLE AROUND MIDNIGHT HAS BEEN RACING EASTWARD ACROSS OKLAHOMA
DURING THE NIGHT.  THE STORMS WILL MOVE RAPIDLY ACROSS EASTERN OKLAHOMA
AND NORTHWEST ARKANSAS THIS MORNING...BEFORE MOVING OFF TO THE EAST BY
LATE THIS MORNING OR EARLY THIS AFTERNOON.

THE STORMS ARE THE RESULT OF A STRONG UPPER LEVEL SYSTEM MOVING
NORTHEASTWARD FROM NEW MEXICO TOWARD THE CENTRAL PLAINS INTERACTING WITH
A DRYLINE AND PACIFIC COLD FRONT AT THE SURFACE OFF TO THE WEST.  WITH
A VERY UNSTABLE ATMOSPHERE AHEAD OF THESE SYSTEMS THE STORMS ARE
EXPECTED TO REMAIN STRONG TO SEVERE AS THEY MOVE ACROSS THE AREA.  THE
GREATEST THREAT WILL BE ACROSS NORTHEAST OKLAHOMA...CLOSER TO THE UPPER
SYSTEM...BUT AN ISOLATED SEVERE THUNDERSTORM OR TWO WITHIN THE LINE MAY
ALSO OCCUR ACROSS SOUTHEAST OKLAHOMA AND NORTHWEST ARKANSAS.  STRONG
DAMAGING WINDS ARE EXPECTED TO BE THE PRIMARY THREAT...BUT LARGE HAIL
MAY ALSO ACCOMPANY A FEW OF THE STORMS.

WITH THE UPPER SYSTEM PULLING AWAY...AND THE RAPID MOVEMENT OF THE
LINE...THE THREAT OF SEVERE WEATHER IS EXPECTED TO END BY AROUND MIDDAY
AS THE STORMS RACE OFF TO THE EAST ACROSS ARKANSAS AND MISSOURI AND
WEAKEN.

CIVIL DEFENSE ORGANIZATIONS AND SPOTTER GROUPS SHOULD EXPECT TO BE
ACTIVATED THIS MORNING IF NOT ALREADY ACTIVATED...ESPECIALLY OVER
NORTHEAST OKLAHOMA.

The office that day

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

IssuedProductOfficeCountiesLasted
May 15, 5:31 AM CDTSevere Thunderstorm WarningTSAOsage59 min
May 15, 5:50 AM CDTSevere Thunderstorm WarningTSAPawnee55 min
May 15, 6:23 AM CDTSevere Thunderstorm WarningTSAOsage52 min
May 15, 6:23 AM CDTSevere Thunderstorm WarningTSAOsage67 min

Nearby

Severe Thunderstorm Warnings in Oklahoma, 1998Every severe thunderstorm warning in 1998

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.