Alert archive / Oklahoma / Tornado Warnings in 1999
Tornado Warning 71, NWS Tulsa, OK
NWS Tulsa, OK issued this tornado warning at May 11, 1999, 10:09 PM CDT for Sequoyah County, Oklahoma. It was in force for 51 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
- May 11, 1999, 10:09 PM CDT (03:09 UTC)
- Expired
- May 11, 1999, 11:00 PM CDT
- In force
- 51 min
- Issued by
- NWS Tulsa, OK
- Area
- Whole counties; the outline is the Mesonet’s reconstruction
County Sequoyah County, OK
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| May 11, 10:37 PM CDT | Tornado F0 | Blackgum, OK | There was a brief tornado touchdown near Aqua Park, causing mainly tree damage. |
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 00:00Z, 3.2 hours before the alert went out and 180 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
- 1007 J/kg
- Mixed-layer CIN
- -54 J/kg
- Mixed-layer LCL
- 1168 m above ground
- 0-6 km bulk shear
- 19 kt
- 0-1 km storm-relative helicity
- 33 m²/s²
- 0-3 km storm-relative helicity
- 83 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 120310 RRA TORTUL OKC135-120400- BULLETIN - EAS ACTIVATION REQUESTED TORNADO WARNING NATIONAL WEATHER SERVICE TULSA OK 1009 PM CDT TUE MAY 11 1999 THE NATIONAL WEATHER SERVICE IN TULSA HAS ISSUED A * TORNADO WARNING FOR SEQUOYAH COUNTY IN EAST CENTRAL OKLAHOMA * UNTIL 1100 PM CDT * AT 1009 PM CDT...RADAR INDICATED A DEVELOPING TORNADO 4 MILES NORTHEAST OF GORE. THIS DANGEROUS STORM IS MOVING EAST AT 15 MPH. * SOME LOCATIONS NEAR THE PATH OF THIS STORM INCLUDE... MARBLE CITY...BRUSHY...GORE...VIAN...GANS AND SALLISAW THIS IS A VERY DANGEROUS STORM. IF YOU ARE NEAR ITS PATH YOU SHOULD PREPARE FOR LARGE DAMAGING HAIL...VIOLENT STRAIGHT LINE WINDS AND POSSIBLY A TORNADO. IF NO UNDERGROUND SHELTER IS AVAILABLE TAKE COVER ON THE LOWEST FLOOR IN AN INTERIOR ROOM AWAY FROM WINDOWS. NIGHTTIME TORNADOES ARE ESPECIALLY DANGEROUS - TAKE COVER NOW IF YOU WAIT UNTIL YOU SEE OR HEAR IT COMING...IT MAY BE TOO LATE TO GET TO A SAFE PLACE LAT...LON 3569 9509 3552 9517 3533 9466 3556 9456
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, 9:54 PM CDT, 15 minutes earlier.
Area forecast discussion, May 11, 9:54 PM CDT, 15 minutes before
EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TULSA OK
954 PM CDT TUE MAY 11 1999
WILL UPDATE SHORTLY TO ACCOUNT FOR MINOR CHANGES BASED ON LATEST
SURFACE ANALYSIS. WILL LOWER TEMPS AND INCREASE WINDS NW OF TUL.
WILL INCREASE POPS ALONG AND EAST OF FRONT WHICH CURRENTLY STRETCHES
FROM JLN-DFW. FRONT HAS BEEN A SLOW MOVER EVER SINCE LAST NIGHT...SO
LOCALLY HEAVY RAINFALL CONTINUES TO BE A THREAT...ESPECIALLY GIVEN
THREE-HOUR FLASH FLOOD GUIDANCE VALUES RANGING FROM 1.5-2.2 INCHES.
GIVEN THE NEAR CERTAINTY OF MORE FLASH FLOOD WARNINGS BEING
ISSUED...WILL ISSUE FLASH FLOOD WATCH FROM WESTERN EDGE OF CURRENT
ACTIVITY TO INLUDE THE WESTERNMOST ARKANSAS COUNTIES IN THE FCST
AREA.
CURRENT STORM IN MUSKOGEE/CHEROKEE/SEQUOYAH COUNTY REGION HAS
HAD ITS ROTATION ENHANCED BY EASTERLY SURFACE WINDS COMING OUT OF
THE ARKANSAS RIVER VALLEY OF WESTERN ARKANSAS...SO ANY STORMS IN
THIS REGION WILL CONTINUE TO HAVE THE HIGHEST POTENTIAL FOR
ROTATION.
FCSTID = 22
.TUL...
AR...FLAHS FLOOD WATCH ZNS 1...10...19...29.
OK...FLASH FLOOD WATCH ALONG AND EAST OF BVO-TUL-MLC-HHW.
SEVERE THUNDERSTORM WATCH UNTIL MIDNIGHT.In the hours before
Local storm report, May 11, 7:15 PM CDT, 2 hours 54 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
715 PM CDT TUE MAY 11 1999
TIME(CDT) .....CITY LOCATION..... STATE ...EVENT/REMARKS...
....COUNTY LOCATION....
0712 PM PRYOR OK .88 INCH HAIL
05/11/99 MAYES
0714 PM CHOUTEAU OK 1.75 INCH HAIL
05/11/99 MAYESLocal storm report, May 11, 7:44 PM CDT, 2 hours 25 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
744 PM CDT TUE MAY 11 1999
TIME(CDT) .....CITY LOCATION..... STATE ...EVENT/REMARKS...
....COUNTY LOCATION....
0729 PM TULLAHASSEE OK .88 INCH HAIL
05/11/99 WAGONERLocal storm report, May 11, 7:44 PM CDT, 2 hours 25 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
744 PM CDT TUE MAY 11 1999
TIME(CDT) .....CITY LOCATION..... STATE ...EVENT/REMARKS...
....COUNTY LOCATION....
0729 PM TULLAHASSEE OK .88 INCH HAIL
05/11/99 WAGONERLocal storm report, May 11, 8:29 PM CDT, 1 hour 40 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
829 PM CDT TUE MAY 11 1999
TIME(CDT) .....CITY LOCATION..... STATE ...EVENT/REMARKS...
....COUNTY LOCATION....
0810 PM BLUFF OK .75 INCH HAIL
05/11/99 CHOCTAW
0823 PM KIOWA OK 1.75 INCH HAIL
05/11/99 PITTSBURGLocal storm report, May 11, 9:25 PM CDT, 44 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
925 PM CDT TUE MAY 11 1999
TIME(CDT) .....CITY LOCATION..... STATE ...EVENT/REMARKS...
....COUNTY LOCATION....
0835 PM 1 E MUSKOGEE OK 1 INCH HAIL
05/11/99 MUSKOGEE
0916 PM 4 S BRAGGS OK TORNADO
05/11/99 MUSKOGEE
0918 PM TAHLEQUAH OK .88 INCH HAIL
05/11/99 CHEROKEE
0920 PM SOPER OK 2 INCH HAIL
05/11/99 CHOCTAWLocal storm report, May 11, 9:59 PM CDT, 10 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
959 PM CDT TUE MAY 11 1999
TIME(CDT) .....CITY LOCATION..... STATE ...EVENT/REMARKS...
....COUNTY LOCATION....
0945 PM BRAGGS OK 1.75 INCH HAIL
05/11/99 MUSKOGEEThe office that day
Everything else NWS Tulsa, OK issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 11, 7:23 PM CDT | Flash Flood Warning | TSA | Mayes | 2 hr |
| May 11, 7:27 PM CDT | Severe Thunderstorm Warning | TSA | Wagoner | 48 min |
| May 11, 7:28 PM CDT | Tornado Warning | TSA | Mayes | 32 min |
| May 11, 7:37 PM CDT | Severe Thunderstorm Warning | TSA | Choctaw | 38 min |
| May 11, 7:40 PM CDT | Severe Thunderstorm Warning | TSA | McIntosh | 35 min |
| May 11, 7:46 PM CDT | Severe Thunderstorm Warning | TSA | Pittsburg | 59 min |
| May 11, 7:53 PM CDT | Tornado Warning | TSA | Cherokee, Mayes | 52 min |
| May 11, 7:57 PM CDT | Severe Thunderstorm Warning | TSA | Cherokee, Muskogee | 48 min |
| May 11, 8:15 PM CDT | Severe Thunderstorm Warning | TSA | Choctaw | 30 min |
| May 11, 8:19 PM CDT | Tornado Warning | TSA | Muskogee | 41 min |
| May 11, 8:28 PM CDT | Severe Thunderstorm Warning | TSA | Pittsburg | 47 min |
| May 11, 8:38 PM CDT | Severe Thunderstorm Warning | TSA | Choctaw | 52 min |
| May 11, 8:44 PM CDT | Severe Thunderstorm Warning | TSA | Pushmataha | 46 min |
| May 11, 8:45 PM CDT | Tornado Warning | TSA | Cherokee, Muskogee | 45 min |
| May 11, 8:46 PM CDT | Tornado Warning | TSA | Choctaw | 29 min |
| May 11, 9:06 PM CDT | Flash Flood Warning | TSA | Muskogee | 3 hr |
| May 11, 9:07 PM CDT | Flash Flood Warning | TSA | Pittsburg, Pushmataha | 2 hr |
| May 11, 9:07 PM CDT | Flash Flood Warning | TSA | Choctaw | 2 hr |
| May 11, 9:11 PM CDT | Tornado Warning | TSA | Choctaw | 34 min |
| May 11, 9:15 PM CDT | Severe Thunderstorm Warning | TSA | Pittsburg | 45 min |
| May 11, 9:25 PM CDT | Tornado Warning | TSA | Muskogee, Sequoyah | 50 min |
| May 11, 9:26 PM CDT | Severe Thunderstorm Warning | TSA | Pushmataha | 49 min |
| May 11, 9:29 PM CDT | Tornado Warning | TSA | Cherokee | 46 min |
| May 11, 9:42 PM CDT | Tornado Warning | TSA | Choctaw | 48 min |
| May 11, 9:54 PM CDT | Severe Thunderstorm Warning | TSA | Rogers, Tulsa | 51 min |
| May 11, 10:16 PM CDT | Severe Thunderstorm Warning | TSA | Pushmataha | 44 min |
| May 11, 10:29 PM CDT | Severe Thunderstorm Warning | TSA | Muskogee, Okmulgee, Wagoner | 46 min |
| May 11, 10:29 PM CDT | Severe Thunderstorm Warning | TSA | Choctaw | 46 min |
| May 11, 10:39 PM CDT | Severe Thunderstorm Warning | TSA | Adair, Cherokee | 51 min |
| May 11, 10:46 PM CDT | Severe Thunderstorm Warning | TSA | LeFlore | 29 min |
| May 11, 10:54 PM CDT | Severe Thunderstorm Warning | TSA | Sequoyah | 51 min |
| May 11, 11:10 PM CDT | Flash Flood Warning | TSA | Choctaw, Pushmataha | 110 min |
| May 11, 11:10 PM CDT | Flash Flood Warning | TSA | Pittsburg | 110 min |
| May 12, 12:40 AM CDT | Flash Flood Warning | TSA | Choctaw, Pushmataha | 3 hr |
| May 12, 3:00 AM CDT | Flash Flood Warning | TSA | Cherokee, Muskogee, Wagoner | 3 hr |
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.