Alert archive / Oklahoma / Severe Thunderstorm Warnings in 1998
Severe Thunderstorm Warning 317, NWS Tulsa, OK
NWS Tulsa, OK issued this severe thunderstorm warning at Jun 18, 1998, 10:33 AM CDT for Sequoyah County, Oklahoma. It was in force for 42 min. 1 report 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
- Jun 18, 1998, 10:33 AM CDT (15:33 UTC)
- Expired
- Jun 18, 1998, 11:15 AM CDT
- In force
- 42 min
- Issued by
- NWS Tulsa, OK
- Area
- Whole counties
County Sequoyah County, OK
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Jun 18, 10:37 AM CDT | Hail 0.75 | Marble City, OK | Summary: an elevated thunderstorm rooted above a cap of warm air in the mid-levels of the atmosphere, briefly strengthened to severe levels while moving across Sequoyah County on the morning of June 18, producing dime-sized hail. |
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, 3.6 hours before the alert went out and 178 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.
- Mixed-layer CAPE
- 1617 J/kg
- Mixed-layer CIN
- -157 J/kg
- Mixed-layer LCL
- 1094 m above ground
- 0-6 km bulk shear
- 30 kt
- 0-1 km storm-relative helicity
- 247 m²/s²
- 0-3 km storm-relative helicity
- 264 m²/s²
- Significant tornado parameter
- 0.4
- Supercell composite
- 3.5
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KTUL 181527 RRA SVRTUL OKC135-181615- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE TULSA OK 1033 AM CDT THU JUN 18 1998 THE NATIONAL WEATHER SERVICE IN TULSA HAS ISSUED A * SEVERE THUNDERSTORM WARNING FOR... SEQUOYAH COUNTY IN EAST CENTRAL OKLAHOMA * UNTIL 1115 AM CDT * AT 1025 AM...NATIONAL WEATHER SERVICE RADAR DETECTED A SEVERE THUNDERSTORM NEAR VIAN...MOVING NORTHEAST AT 30 MPH. * SOME LOCATIONS AFFECTED INCLUDE... VIAN BRUSHY MARBLE CITY SALLISAW HAIL TO THE SIZE OF NICKLES AND WIND GUSTS TO 60 MPH CAN BE EXPECTED IN THE WARNED AREA. BE ALERT TO RAPIDLY CHANGING WEATHER CONDITIONS AS STORMS APPROACH.
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 Jun 18, 10:30 AM CDT, 3 minutes earlier.
Area forecast discussion, Jun 18, 10:30 AM CDT, 3 minutes before
EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION NATIONAL WEATHER SERVICE TULSA OK 1030 AM CDT THU JUN 18 1998 ELEVATED CONVECTION CONTINUING OVER FAR E OK AND NW AR IN RESPONSE TO LLJ. WAS A LITTLE UNSURE ON HOW TO HANDLE POPS..BUT WITH ADDITIONAL DEVELOPMENT NOTED OVER FAR E OK...WILL LEAVE POPS ALONE. WILL HAVE TO KEEP AN EYE ON TEMPS AS LONGEVITY OF CONVECTION/CLOUDS OVER ERN ZONES MAY HAMPER FCSTD HIGHS. OTHERWISE REST OF ZNS LOOK GOOD WITH NO CHANGES TO LATER PDS. ETA NOT IN YET...AVAILABLE NEW GUIDANCE SUGGESTS FRONT TO APPROACH WRN ZNS AROUND 0Z. FCSTID = 23 .TUL... OK...NONE. AR...NONE. -
In the hours before
Special weather statement, Jun 18, 6:00 AM CDT, 4 hours 33 minutes before
ARZ001-002-010-011-019-020-029-OKZ049-053>076-191200- EASTERN OKLAHOMA/NORTHWEST ARKANSAS HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE TULSA OK 600 AM CDT THU JUN 18 1998 A FEW SEVERE THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON AND EVENING ACROSS PORTIONS OF EASTERN OKLAHOMA AND NORTHWEST ARKANSAS. SCATTERED HIGH BASED SHOWERS AND ISOLATED THUNDERSTORMS WILL CONTINUE TO MOVE NORTHEAST ACROSS EASTERN OKLAHOMA AND NORTHWEST ARKANSAS THIS MORNING. A CAPPING LAYER OF WARM AIR IN THE UPPER LEVELS WILL TEND TO SUPPRESS ANY STRONG THUNDERSTORM DEVELOPMENT WITH THIS ACTIVITY THROUGH MIDDAY. MEANWHILE...A VIGOROUS UPPER LEVEL LOW PRESSURE SYSTEM WILL CONTINUE TO MOVE ACROSS NORTHERN NEBRASKA. AS THIS SYSTEM PASSES TO THE NORTH...A SURFACE COLD FRONT WILL MOVE INTO NORTHEAST OKLAHOMA DURING THE AFTERNOON. LOW LEVEL CONVERGENCE NEAR THIS FRONTAL BOUNDARY ALONG WITH COOLER TEMPERATURES ALOFT WILL HELP TO FURTHER DESTABILIZE THE ATMOSPHERE...SETTING THE STAGE FOR THE DEVELOPMENT OF A FEW SEVERE THUNDERSTORMS ROUGHLY ALONG INTERSTATE 44 BY 3 PM. AS THE AFTERNOON PROGRESSES...THE BEST CHANCES FOR SEVERE THUNDERSTORMS ARE EXPECTED TO BE FOR AREAS SOUTH AND EAST OF TULSA...INCLUDING THE MIAMI...MUSKOGEE...MCALESTER...FAYETTEVILLE...AND THE FORT SMITH AREAS WHERE COLDER UPPER LEVEL TEMPERATURES SHOULD WEAKEN THE CAP JUST AS AFTERNOON HEATING MAKES THE ATMOSPHERE THE MOST UNSTABLE. BY MID AFTERNOON...THE SURFACE FRONT SHOULD BE JUST NORTH OF INTERSTATE 44 ACTING AS A FOCUS FOR THUNDERSTORM DEVELOPMENT. THE STORMS THAT DEVELOP ALONG THE FRONT WILL MOVE EASTWARD INTO AN INCREASINGLY UNSTABLE AIRMASS WELL INTO THE EVENING HOURS. THE MAIN THREAT WITH ANY SEVERE STORMS THIS AFTERNOON AND EVENING WILL BE LARGE HAIL AND DAMAGING WINDS. HOWEVER...A FEW ISOLATED TORNADOES WILL BE POSSIBLE IN THE AFTERNOON AND EARLY EVENING HOURS WHEN THE ATMOSPHERE WILL BE THE MOST UNSTABLE. STORM SPOTTERS AND EMERGENCY MANAGEMENT GROUPS ACROSS EASTERN OKLAHOMA AND NORTHWEST ARKANSAS SHOULD CONTINUE TO MONITOR THIS SITUATION AND BE READY FOR POSSIBLE SEVERE WEATHER ACTIVATION LATER THIS AFTERNOON. AN UPDATED HAZARDOUS WEATHER OUTLOOK WILL BE ISSUED BY THE NATIONAL WEATHER SERVICE IN TULSA AROUND 1 PM TODAY.
Special weather statement, Jun 18, 6:00 AM CDT, 4 hours 33 minutes before
ARZ001-002-010-011-019-020-029-OKZ049-053>076-191200- EASTERN OKLAHOMA/NORTHWEST ARKANSAS HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE TULSA OK 600 AM CDT THU JUN 18 1998 A FEW SEVERE THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON AND EVENING ACROSS PORTIONS OF EASTERN OKLAHOMA AND NORTHWEST ARKANSAS. SCATTERED HIGH BASED SHOWERS AND ISOLATED THUNDERSTORMS WILL CONTINUE TO MOVE NORTHEAST ACROSS EASTERN OKLAHOMA AND NORTHWEST ARKANSAS THIS MORNING. A CAPPING LAYER OF WARM AIR IN THE UPPER LEVELS WILL TEND TO SUPPRESS ANY STRONG THUNDERSTORM DEVELOPMENT WITH THIS ACTIVITY THROUGH MIDDAY. MEANWHILE...A VIGOROUS UPPER LEVEL LOW PRESSURE SYSTEM WILL CONTINUE TO MOVE ACROSS NORTHERN NEBRASKA. AS THIS SYSTEM PASSES TO THE NORTH...A SURFACE COLD FRONT WILL MOVE INTO NORTHEAST OKLAHOMA DURING THE AFTERNOON. LOW LEVEL CONVERGENCE NEAR THIS FRONTAL BOUNDARY ALONG WITH COOLER TEMPERATURES ALOFT WILL HELP TO FURTHER DESTABILIZE THE ATMOSPHERE...SETTING THE STAGE FOR THE DEVELOPMENT OF A FEW SEVERE THUNDERSTORMS ROUGHLY ALONG INTERSTATE 44 BY 3 PM. AS THE AFTERNOON PROGRESSES...THE BEST CHANCES FOR SEVERE THUNDERSTORMS ARE EXPECTED TO BE FOR AREAS SOUTH AND EAST OF TULSA...INCLUDING THE MIAMI...MUSKOGEE...MCALESTER...FAYETTEVILLE...AND THE FORT SMITH AREAS WHERE COLDER UPPER LEVEL TEMPERATURES SHOULD WEAKEN THE CAP JUST AS AFTERNOON HEATING MAKES THE ATMOSPHERE THE MOST UNSTABLE. BY MID AFTERNOON...THE SURFACE FRONT SHOULD BE JUST NORTH OF INTERSTATE 44 ACTING AS A FOCUS FOR THUNDERSTORM DEVELOPMENT. THE STORMS THAT DEVELOP ALONG THE FRONT WILL MOVE EASTWARD INTO AN INCREASINGLY UNSTABLE AIRMASS WELL INTO THE EVENING HOURS. THE MAIN THREAT WITH ANY SEVERE STORMS THIS AFTERNOON AND EVENING WILL BE LARGE HAIL AND DAMAGING WINDS. HOWEVER...A FEW ISOLATED TORNADOES WILL BE POSSIBLE IN THE AFTERNOON AND EARLY EVENING HOURS WHEN THE ATMOSPHERE WILL BE THE MOST UNSTABLE. STORM SPOTTERS AND EMERGENCY MANAGEMENT GROUPS ACROSS EASTERN OKLAHOMA AND NORTHWEST ARKANSAS SHOULD CONTINUE TO MONITOR THIS SITUATION AND BE READY FOR POSSIBLE SEVERE WEATHER ACTIVATION LATER THIS AFTERNOON. AN UPDATED HAZARDOUS WEATHER OUTLOOK WILL BE ISSUED BY THE NATIONAL WEATHER SERVICE IN TULSA AROUND 1 PM TODAY.
The office that day
Everything else NWS Tulsa, OK issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 18, 4:36 PM CDT | Severe Thunderstorm Warning | TSA | Creek | 54 min |
| Jun 18, 4:46 PM CDT | Severe Thunderstorm Warning | TSA | Nowata, Washington | 44 min |
| Jun 18, 5:05 PM CDT | Severe Thunderstorm Warning | TSA | Tulsa | 55 min |
| Jun 18, 5:27 PM CDT | Tornado Warning | TSA | Creek, Tulsa | 48 min |
| Jun 18, 5:30 PM CDT | Severe Thunderstorm Warning | TSA | Craig, Nowata | 45 min |
| Jun 18, 5:47 PM CDT | Flash Flood Warning | TSA | Creek, Tulsa | 103 min |
| Jun 18, 5:57 PM CDT | Severe Thunderstorm Warning | TSA | Okfuskee | 63 min |
| Jun 18, 6:09 PM CDT | Severe Thunderstorm Warning | TSA | Wagoner | 36 min |
| Jun 18, 6:15 PM CDT | Severe Thunderstorm Warning | TSA | Tulsa | 45 min |
| Jun 18, 6:22 PM CDT | Severe Thunderstorm Warning | TSA | Muskogee, Okmulgee | 53 min |
| Jun 18, 6:38 PM CDT | Tornado Warning | TSA | Muskogee, Wagoner | 37 min |
| Jun 18, 6:50 PM CDT | Severe Thunderstorm Warning | TSA | Okfuskee, Okmulgee | 55 min |
| Jun 18, 6:53 PM CDT | Flash Flood Warning | TSA | Okfuskee | 2 hr |
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.