Alert archive / Oklahoma / Tornado Warnings in 1999
Tornado Warning 60, NWS Tulsa, OK
NWS Tulsa, OK issued this tornado warning at May 11, 1999, 6:27 PM CDT for Mayes County, Rogers County, Oklahoma. It was in force for 33 min. 2 reports 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
- May 11, 1999, 6:27 PM CDT (23:27 UTC)
- Expired
- May 11, 1999, 7:00 PM CDT
- In force
- 33 min
- Issued by
- NWS Tulsa, OK
- Area
- Whole counties; the outline is the Mesonet’s reconstruction
Counties Mayes County, OK, Rogers County, OK
The radar
The Tulsa radar (KINX), 18 km from the middle of the area, began a volume at 23:29 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
| Time | Report | Where | Remark |
|---|---|---|---|
| May 11, 6:48 PM CDT | Hail 1 | Pryor, OK | There were several reports of dime and quarter-sized hail southwest of Pryor. |
| May 11, 7:07 PM CDT | Hail 0.88 | Pryor, OK | There was a report of dime-sized hail 3 miles south of Pryor at 707 PM CDT, while there was a report of nickel-sized hail in Pryor at 713 PM CDT. |
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.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| May 11, 6:15 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
The nearest sounding before it
Springfield, MO (KSGF), launched 12:00Z, 11.5 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.
- Mixed-layer CAPE
- 60 J/kg
- Mixed-layer CIN
- -204 J/kg
- Mixed-layer LCL
- 878 m above ground
- 0-6 km bulk shear
- 17 kt
- 0-1 km storm-relative helicity
- 90 m²/s²
- 0-3 km storm-relative helicity
- 94 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
999 WFUS54 KTSA 112328 RRA TORTUL OKC097-131-120000- BULLETIN - EAS ACTIVATION REQUESTED TORNADO WARNING NATIONAL WEATHER SERVICE TULSA OK 627 PM CDT TUE MAY 11 1999 THE NATIONAL WEATHER SERVICE IN TULSA HAS ISSUED A * TORNADO WARNING FOR MAYES COUNTY IN NORTHEAST OKLAHOMA EXTREME EASTERN ROGERS COUNTY IN NORTHEAST OKLAHOMA * UNTIL 700 PM CDT * AT 627 PM CDT...RADAR INDICATED A SEVERE THUNDERSTORM WITH STRONG ROTATION 8 MILES SOUTHWEST OF PRYOR NEAR THE ROGERS COUNTY LINE. THIS STORM IS MOVING NORTHEAST AT 10 MPH...THIS DANGEROUS STORM COULD PRODUCE A TORNADO AT ANY TIME. * SOME LOCATIONS NEAR THE PATH OF THIS STORM INCLUDE... PRYOR AND ADAIR IF YOU ARE IN OR NEAR THE PATH OF THIS STORM...TAKE COVER NOW IF NO UNDERGROUND SHELTER IS AVAILABLE MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR. MOBILE HOMES AND VEHICLES SHOULD BE ABANDONED FOR MORE SUBSTANTIAL SHELTER. AVOID WINDOWS IN ADDITION TO THE THREAT OF A TORNADO...LARGE HAIL AND DAMAGING STRAIGHT LINE WINDS CAN BE EXPECTED WITH THIS STORM. GO TO A SAFE PLACE NOW LAT...LON 3629 9560 3614 9548 3628 9515 3647 9530
What forecasters said that day
The local office's own words before this tornado 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 tornado warning went out at May 11, 3:45 PM CDT, 2 hours 42 minutes earlier.
Area forecast discussion, May 11, 3:45 PM CDT, 2 hours 42 minutes before
EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION NATIONAL WEATHER SERVICE TULSA OK 345 PM CDT TUE MAY 11 1999 PROBLEM(S) OF THE DAY: WILL THERE BE SEVERE CONVECTION? WILL THERE BE HEAVY RAINFALL? POPS CLOUDS HANGING TOUGH THIS AFTERNOON OVER MUCH OF THE FA...BUT ABUNDANT SUNSHINE PREVAILED OVER FAR ERN OK AND PORTIONS OF NW ARKANSAS. SURFACE FRONT HAS PORGRESSED AT A SNAILS PACE...WITH MID AFTERNOON POSTIONING JUST EAST OF A KANSAS CITY TO OKLAHOMA CITY TO WICHITA FALLS LINE. LOTS OF CLOUDS AND WARM AIR ALOFT HAS KEPT CONVECTION IN CHECK THUS FAR. COULD STILL SEE SOME ACTIVITY FIRE ALONG THE FRONT LATE THIS AFTERNOON...PARTICULARY IN AREAS NORTH AND OF TUL. UPPER TROUGH STILL EXPECTED TO LIFT OUT TONIGHT BRINGING ASSOCIATED S/W ENERGY ACROSS THE AREA. SURFACE FRONT SHOULD PROGRESS EASTWARD IN RESPONSE TO UPPER SYSTEM LIFTING OUT. EXPECT SHOWERS AND STORMS TO FIRE IN VICINITY OF FRONT AS THE COLDER AIR ALOFT WEAKENS THE CAP. ACTIVITY MAY FORM INTO A COMPLEX OF STORMS AS ACTIVITY MOVES ACROSS THE FA TONIGHT AND EARLY TOMORROW MORNING. ETA CONSISTENT WITH PLACING ERN OK IN RIGHT ENTRANCE REGION OF H3 80 KT JET MAX. LOOKS LIKE BEST LIFT WILL BE OVER NE OK AND NW ARKANSAS. THERE COULD ALSO BE SOME HEAVY RAINS WITH SLOW MOVING FRONT. WILL NOT ISSUE FFA AT THIS TIME AS MOST PRECIP IS EXPECTED OVER AREAS WHERE FFG VALUES ARE THE HIGHEST. FRONT EXPECTED TO BE THROUGH NW AR AND SE OK BY 12Z TOMORROW. WILL LEAVE LOW POPS IN FOR MORNING TO COVER LINGERING ACTIVITY. DRIER AIR ADVECTING IN BEHIND THE FRONT SHOULD RESULT IN A PARTLY CLOUDY SKY OVER THE FA TOMORROW AFTERNOON AND NIGHT. STUCK PRETTY CLOSE TO GUIDANCE(NGM MOS AVAILABLE) BUT OPTED FOR COOLER FAN NUMBERS IN LATER PERIODS. IN THE EXTENDED...WILL KEEP DRY AS MOST EXTENDED MODELS ARE CONSISTENT WITH WEAK H5 RIDGING SETTING UP FRI AND SAT. LEE TROUGHING WILL RESULT IN RETURN FLOW AT THE SURFACE BY FRIDAY. UPPER RIDGE SHIFTS OFF TO THE EAST WITH SW FLOW SETTING UP AGAIN SUNDAY. THIS AND A SURFACE DRYLINE/PACIFIC FRONT TO THE WEST OF FA WARRANTS CHANCE POPS FOR SUNDAY. FCSTID = 23 TUL 57 75 56 79 / 60 20 0 0 FSM 59 77 55 80 / 50 30 0 0 MLC 60 78 56 80 / 50 20 0 0 BVO 58 74 53 79 / 60 20 0 0 FYV 57 73 52 78 / 60 30 0 0 IDB 60 80 58 82 / 40 20 0 0 BYV 56 72 51 77 / 60 30 0 0 MIO 58 80 52 77 / 60 30 0 0 MKO 58 76 55 80 / 60 20 0 0 F10 57 75 56 79 / 60 20 0 0 HHW 60 80 58 82 / 40 20 0 0 .TUL... AR...NONE. OK...NONE. -------------------- EXPERIMENTAL OUTPUT: HAZARDOUS WEATHER EXPECTED NEXT 24 HOURS: CHANCE SEVERE THUNDERSTORMS NGM CONFIDENCE: MODEL OUTPUT NOT AVAILABLE ETA CONFIDENCE: 7 ON A SCALE OF 0 TO 10 AVN CONFIDENCE: 7 ON A SCALE OF 0 TO 10 FCST CONFIDENCE: 8 ON A SCALE OF 0 TO 10
In the hours before
Special weather statement, May 11, 1:00 PM CDT, 5 hours 27 minutes before
ARZ001-002-010-011-019-020-029-OKZ049-053>076-121100- EASTERN OKLAHOMA/NORTHWEST ARKANSAS HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE TULSA OK 100 PM CDT TUE MAY 11 1999 ...A FEW SEVERE THUNDERSTORMS ARE EXPECTED ACROSS EASTERN OKLAHOMA AND NORTHWEST ARKANSAS TONIGHT... .SYNOPSIS... A COLD FRONT WAS LOCATED FROM NORTHWEST OF BARTLESVILLE TO WEST OF ARDMORE EARLY THIS AFTERNOON. THE FRONT WILL MOVE SLOWLY EAST THROUGH TONIGHT AND WILL EXTEND FROM NORTHWEST ARKANSAS INTO SOUTHEAST OKLAHOMA BY SUNRISE WEDNESDAY. AN UPPER LEVEL TROUGH OF LOW PRESSURE WAS LOCATED ACROSS EASTERN NEW MEXICO AND WILL MOVE EAST INTO OKLAHOMA TONIGHT. THE COLD FRONT WILL BE A FOCUS FOR THUNDERSTORM DEVELOPMENT LATE THIS AFTERNOON OR THIS EVENING AS THE UPPER LEVEL TROUGH APPROACHES. A FEW SEVERE THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG OR AHEAD OF THE COLD FRONT THROUGH TONIGHT. .DISCUSSION... A CAP OF WARM AIR ALOFT WILL INHIBIT THUNDERSTORM DEVELOPMENT FOR MOST OF THE AFTERNOON HOURS. AS COLDER AIR ALOFT MOVES INTO THE AREA THIS EVENING AND OVERNIGHT...THUNDERSTORMS WILL GRADUALLY BECOME MORE NUMEROUS NEAR THE FRONT. A MODERATELY UNSTABLE AIRMASS WILL LEAD TO A FEW SEVERE THUNDERSTORMS THIS EVENING AND OVERNIGHT AS STRENGTHENING WINDS ALOFT ACT TO ORGANIZE DEVELOPMENT. ALTHOUGH WIND FIELDS ARE NOT EXPECTED TO BE IDEAL FOR SUPERCELLS...A FEW ROTATING THUNDERSTORMS WILL BE POSSIBLE ACROSS EASTERN OKLAHOMA THIS EVENING. THE PRIMARY MODE OF SEVERE CONVECTION OVERNIGHT IS EXPECTED TO BE BOW ECHO LINE SEGMENTS. LARGE HAIL AND DAMAGING STRAIGHT LINE WINDS WILL BE POSSIBLE WITH SEVERE THUNDERSTORMS TONIGHT. CONVECTION WILL LIKELY ORGANIZE INTO A COMPLEX OF MULTICELL THUNDERSTORMS BY MIDNIGHT AND MOVE EAST ACROSS THE AREA OVERNIGHT. LOCALLY HEAVY RAINS CAN BE EXPECTED AS THUNDERSTORMS CONTINUE TO DEVELOP AND MOVE NORTHEAST ALONG THE SLOW MOVING FRONT. .EMERGENCY MANAGEMENT AGENCY AND SPOTTER ACTIVATION... EMERGENCY MANAGEMENT AGENCIES AND STORM SPOTTER GROUPS IN EASTERN OKLAHOMA SHOULD BE PREPARED FOR ACTIVATION BY 7 PM. STORM SPOTTER ACTIVATION MAY BE NEEDED IN NORTHWEST ARKANSAS AFTER 10 PM.
Special weather statement, May 11, 1:00 PM CDT, 5 hours 27 minutes before
ARZ001-002-010-011-019-020-029-OKZ049-053>076-121100- EASTERN OKLAHOMA/NORTHWEST ARKANSAS HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE TULSA OK 100 PM CDT TUE MAY 11 1999 ...A FEW SEVERE THUNDERSTORMS ARE EXPECTED ACROSS EASTERN OKLAHOMA AND NORTHWEST ARKANSAS TONIGHT... .SYNOPSIS... A COLD FRONT WAS LOCATED FROM NORTHWEST OF BARTLESVILLE TO WEST OF ARDMORE EARLY THIS AFTERNOON. THE FRONT WILL MOVE SLOWLY EAST THROUGH TONIGHT AND WILL EXTEND FROM NORTHWEST ARKANSAS INTO SOUTHEAST OKLAHOMA BY SUNRISE WEDNESDAY. AN UPPER LEVEL TROUGH OF LOW PRESSURE WAS LOCATED ACROSS EASTERN NEW MEXICO AND WILL MOVE EAST INTO OKLAHOMA TONIGHT. THE COLD FRONT WILL BE A FOCUS FOR THUNDERSTORM DEVELOPMENT LATE THIS AFTERNOON OR THIS EVENING AS THE UPPER LEVEL TROUGH APPROACHES. A FEW SEVERE THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG OR AHEAD OF THE COLD FRONT THROUGH TONIGHT. .DISCUSSION... A CAP OF WARM AIR ALOFT WILL INHIBIT THUNDERSTORM DEVELOPMENT FOR MOST OF THE AFTERNOON HOURS. AS COLDER AIR ALOFT MOVES INTO THE AREA THIS EVENING AND OVERNIGHT...THUNDERSTORMS WILL GRADUALLY BECOME MORE NUMEROUS NEAR THE FRONT. A MODERATELY UNSTABLE AIRMASS WILL LEAD TO A FEW SEVERE THUNDERSTORMS THIS EVENING AND OVERNIGHT AS STRENGTHENING WINDS ALOFT ACT TO ORGANIZE DEVELOPMENT. ALTHOUGH WIND FIELDS ARE NOT EXPECTED TO BE IDEAL FOR SUPERCELLS...A FEW ROTATING THUNDERSTORMS WILL BE POSSIBLE ACROSS EASTERN OKLAHOMA THIS EVENING. THE PRIMARY MODE OF SEVERE CONVECTION OVERNIGHT IS EXPECTED TO BE BOW ECHO LINE SEGMENTS. LARGE HAIL AND DAMAGING STRAIGHT LINE WINDS WILL BE POSSIBLE WITH SEVERE THUNDERSTORMS TONIGHT. CONVECTION WILL LIKELY ORGANIZE INTO A COMPLEX OF MULTICELL THUNDERSTORMS BY MIDNIGHT AND MOVE EAST ACROSS THE AREA OVERNIGHT. LOCALLY HEAVY RAINS CAN BE EXPECTED AS THUNDERSTORMS CONTINUE TO DEVELOP AND MOVE NORTHEAST ALONG THE SLOW MOVING FRONT. .EMERGENCY MANAGEMENT AGENCY AND SPOTTER ACTIVATION... EMERGENCY MANAGEMENT AGENCIES AND STORM SPOTTER GROUPS IN EASTERN OKLAHOMA SHOULD BE PREPARED FOR ACTIVATION BY 7 PM. STORM SPOTTER ACTIVATION MAY BE NEEDED IN NORTHWEST ARKANSAS AFTER 10 PM.
Local storm report, May 11, 6:04 PM CDT, 23 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
604 PM CDT TUE MAY 11 1999
TIME(CDT) .....CITY LOCATION..... STATE ...EVENT/REMARKS...
....COUNTY LOCATION....
0601 PM 8 NW PRYOR OK .75 INCH HAIL
05/11/99 MAYES FIRE DEPT REPT OF DIME
HAIL ON TURNPIKE AT
MAYES/ROGERS CO. LINELocal storm report, May 11, 6:04 PM CDT, 23 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
604 PM CDT TUE MAY 11 1999
TIME(CDT) .....CITY LOCATION..... STATE ...EVENT/REMARKS...
....COUNTY LOCATION....
0601 PM 8 NW PRYOR OK .75 INCH HAIL
05/11/99 MAYES FIRE DEPT REPT OF DIME
HAIL ON TURNPIKE AT
MAYES/ROGERS CO. LINELocal storm report, May 11, 6:12 PM CDT, 15 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
612 PM CDT TUE MAY 11 1999
TIME(CDT) .....CITY LOCATION..... STATE ...EVENT/REMARKS...
....COUNTY LOCATION....
0440 PM 2 W PRYOR OK 2.75 INCH HAIL
05/11/99 MAYESLocal storm report, May 11, 6:13 PM CDT, 14 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
613 PM CDT TUE MAY 11 1999
TIME(CDT) .....CITY LOCATION..... STATE ...EVENT/REMARKS...
....COUNTY LOCATION....
0610 PM 8 E CLAREMORE OK .75 INCH HAIL
05/11/99 ROGERS ON HWY 20...SPOTTER
REPORTThe office that day
Everything else NWS Tulsa, OK issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 11, 5:40 PM CDT | Severe Thunderstorm Warning | TSA | Mayes, Rogers | 35 min |
| May 11, 6:12 PM CDT | Severe Thunderstorm Warning | TSA | Mayes, Rogers | 48 min |
| May 11, 6:53 PM CDT | Tornado Warning | TSA | Mayes | 37 min |
Nearby
Tornado Warnings in Oklahoma, 1999Every tornado warning in 1999Tornadoes 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.