Alert archive / Oklahoma / Severe Thunderstorm Warnings in 1999
Severe Thunderstorm Warning 408, NWS Tulsa, OK
NWS Tulsa, OK issued this severe thunderstorm warning at Jul 1, 1999, 10:56 AM CDT for Osage County, Oklahoma. It was in force for 34 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
- Jul 1, 1999, 10:56 AM CDT (15:56 UTC)
- Expired
- Jul 1, 1999, 11:30 AM CDT
- In force
- 34 min
- Issued by
- NWS Tulsa, OK
- Area
- Whole counties
County Osage County, OK
The radar
The Tulsa radar (KINX), 90 km from the middle of the area, began a volume at 15:57 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 |
|---|---|---|---|
| Jul 1, 11:12 AM CDT | Hail 1 | Osage, 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.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| Jul 1, 8:15 AM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
The nearest sounding before it
Norman, OK (KOUN), launched 12:00Z, 3.9 hours before the alert went out and 181 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
- 914 J/kg
- Mixed-layer CIN
- -447 J/kg
- Mixed-layer LCL
- 769 m above ground
- 0-6 km bulk shear
- 28 kt
- 0-1 km storm-relative helicity
- 277 m²/s²
- 0-3 km storm-relative helicity
- 241 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.1
The text
The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.
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 Jul 1, 10:40 AM CDT, 16 minutes earlier.
Area forecast discussion, Jul 1, 10:40 AM CDT, 16 minutes before
EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION NATIONAL WEATHER SERVICE TULSA OK 1040 AM CDT THU JUL 1 1999 JUST UPDATED THE ZONES AGAIN TO REMOVE 10AM EXPIRATION WATCH. TWO STORMS OVER WESTERN OSAGE COUNTY HAVE NOW BECOME ONE AND MAY STILL PRODUCE SOME PROBLEMS BUT WIDESPREAD ACTIVITY NOT LIKELY SO LET THAT WATCH GO. 200PM WATCH STILL IN EFFECT AND WILL REQUIRE ANOTHER UPDATE LATER. OTHERWISE NO MAJOR CHANGES MADE AT THIS TIME. LEFT THE FLASH FLOOD WATCH ALONE FOR NOW. HOWIESON FCSTID = 44 .TUL... AR...FLASH FLOOD WATCH FOR THIS MORNING FOR ZONES ARZ001>002... ARZ010>011...ARZ019>020...ARZ029. OK...FLASH FLOOD WATCH FOR THIS MORNING FOR ZONES OKZ054>076.
In the hours before
Special weather statement, Jul 1, 6:10 AM CDT, 4 hours 46 minutes before
ARZ001-002-010-011-019-020-029-OKZ049-053>076-021100- EASTERN OKLAHOMA/NORTHWEST ARKANSAS HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE TULSA OK 610 AM CDT THU JUL 1 1999 ...A SEVERE THUNDERSTORM WATCH IS IN EFFECT UNTIL 10 AM FOR OSAGE... PAWNEE AND CREEK COUNTIES IN NORTHEAST OKLAHOMA... ...A FLASH FLOOD WATCH IS IN EFFECT FOR THIS MORNING FOR MUCH OF EASTERN OKLAHOMA AND NORTHWEST ARKANSAS... ...A FEW SEVERE THUNDERSTORMS ARE EXPECTED OVER NORTHEAST OKLAHOMA THIS MORNING... .SYNOPSIS... EARLY THIS MORNING LOW PRESSURE WAS LOCATED OVER THE TEXAS AND OKLAHOMA PANHANDLES. A STRONG LOW LEVEL JET HAS DEVELOPED OVERNIGHT OVER THE SOUTHERN PLAINS AHEAD OF THIS FEATURE. THIS JET COMBINED WITH APPROACHING RELATIVELY STRONG WINDS IN THE MID LEVELS OF THE ATMOSPHERE WILL PROVIDE AN ENVIRONMENT FAVORABLE FOR SEVERE THUNDERSTORMS OVER NORTHEAST OKLAHOMA THIS MORNING. WIND FIELDS WILL WEAKEN SOMEWHAT THIS AFTERNOON AND TONIGHT AND WARMING MID LEVELS OF THE ATMOSPHERE WILL ACT TO SUPPRESS THE REDEVELOPMENT OF THUNDERSTORMS LATER IN THE DAY AND OVERNIGHT TONIGHT. .DISCUSSION... A COMPLEX OF STRONG TO SEVERE THUNDERSTORMS FORMED OVER SOUTHWEST KANSAS OVERNIGHT. THE LEADING EDGE OF THIS COMPLEX OF STORMS IS EXPECTED TO DEVELOP INTO A SQUALL LINE AND MOVE SOUTHEAST ACROSS EASTERN OKLAHOMA AND NORTHWEST ARKANSAS THIS MORNING. THE THUNDERSTORMS WILL LIKELY WEAKEN AS THEY CROSS THE AREA. HOWEVER...THEY WILL LIKELY REMAIN STRONG ENOUGH TO PRODUCE SOME DAMAGING WINDS AND MARGINALLY SEVERE HAIL ACROSS NORTHEAST OKLAHOMA . THE STORMS WILL ALSO BRING A PERIOD OF VERY HEAVY RAINFALL WHICH COMBINED WITH SOILS THAT ARE SATURATED FROM LAST MORNINGS RAIN COULD RESULT IN FLASH FLOODING. .EMERGENCY MANAGEMENT AGENCY AND SPOTTER ACTIVATION... CIVIL DEFENSE AGENCIES AND SPOTTER GROUPS OVER NORTHEAST OKLAHOMA SHOULD BE PREPARED FOR POSSIBLE ACTIVATION THIS MORNING. INFORMATION CONCERNING THE DEVELOPMENT OF FLASH FLOODING MAY BE NEEDED OVER THE WHOLE AREA.
Special weather statement, Jul 1, 6:10 AM CDT, 4 hours 46 minutes before
ARZ001-002-010-011-019-020-029-OKZ049-053>076-021100- EASTERN OKLAHOMA/NORTHWEST ARKANSAS HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE TULSA OK 610 AM CDT THU JUL 1 1999 ...A SEVERE THUNDERSTORM WATCH IS IN EFFECT UNTIL 10 AM FOR OSAGE... PAWNEE AND CREEK COUNTIES IN NORTHEAST OKLAHOMA... ...A FLASH FLOOD WATCH IS IN EFFECT FOR THIS MORNING FOR MUCH OF EASTERN OKLAHOMA AND NORTHWEST ARKANSAS... ...A FEW SEVERE THUNDERSTORMS ARE EXPECTED OVER NORTHEAST OKLAHOMA THIS MORNING... .SYNOPSIS... EARLY THIS MORNING LOW PRESSURE WAS LOCATED OVER THE TEXAS AND OKLAHOMA PANHANDLES. A STRONG LOW LEVEL JET HAS DEVELOPED OVERNIGHT OVER THE SOUTHERN PLAINS AHEAD OF THIS FEATURE. THIS JET COMBINED WITH APPROACHING RELATIVELY STRONG WINDS IN THE MID LEVELS OF THE ATMOSPHERE WILL PROVIDE AN ENVIRONMENT FAVORABLE FOR SEVERE THUNDERSTORMS OVER NORTHEAST OKLAHOMA THIS MORNING. WIND FIELDS WILL WEAKEN SOMEWHAT THIS AFTERNOON AND TONIGHT AND WARMING MID LEVELS OF THE ATMOSPHERE WILL ACT TO SUPPRESS THE REDEVELOPMENT OF THUNDERSTORMS LATER IN THE DAY AND OVERNIGHT TONIGHT. .DISCUSSION... A COMPLEX OF STRONG TO SEVERE THUNDERSTORMS FORMED OVER SOUTHWEST KANSAS OVERNIGHT. THE LEADING EDGE OF THIS COMPLEX OF STORMS IS EXPECTED TO DEVELOP INTO A SQUALL LINE AND MOVE SOUTHEAST ACROSS EASTERN OKLAHOMA AND NORTHWEST ARKANSAS THIS MORNING. THE THUNDERSTORMS WILL LIKELY WEAKEN AS THEY CROSS THE AREA. HOWEVER...THEY WILL LIKELY REMAIN STRONG ENOUGH TO PRODUCE SOME DAMAGING WINDS AND MARGINALLY SEVERE HAIL ACROSS NORTHEAST OKLAHOMA . THE STORMS WILL ALSO BRING A PERIOD OF VERY HEAVY RAINFALL WHICH COMBINED WITH SOILS THAT ARE SATURATED FROM LAST MORNINGS RAIN COULD RESULT IN FLASH FLOODING. .EMERGENCY MANAGEMENT AGENCY AND SPOTTER ACTIVATION... CIVIL DEFENSE AGENCIES AND SPOTTER GROUPS OVER NORTHEAST OKLAHOMA SHOULD BE PREPARED FOR POSSIBLE ACTIVATION THIS MORNING. INFORMATION CONCERNING THE DEVELOPMENT OF FLASH FLOODING MAY BE NEEDED OVER THE WHOLE AREA.
The office that day
Everything else NWS Tulsa, OK issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 1, 7:42 AM CDT | Severe Thunderstorm Warning | TSA | Osage, Pawnee | 48 min |
| Jul 1, 8:13 AM CDT | Severe Thunderstorm Warning | TSA | Creek | 62 min |
| Jul 1, 8:24 AM CDT | Severe Thunderstorm Warning | TSA | Osage, Pawnee | 36 min |
| Jul 1, 8:32 AM CDT | Severe Thunderstorm Warning | TSA | Tulsa, Washington | 58 min |
| Jul 1, 8:53 AM CDT | Severe Thunderstorm Warning | TSA | Nowata, Rogers | 52 min |
| Jul 1, 9:18 AM CDT | Severe Thunderstorm Warning | TSA | Delaware, Ottawa | 42 min |
| Jul 1, 9:48 AM CDT | Severe Thunderstorm Warning | TSA | Delaware, Ottawa | 42 min |
| Jul 1, 10:02 AM CDT | Severe Thunderstorm Warning | TSA | Cherokee | 43 min |
| Jul 1, 10:17 AM CDT | Severe Thunderstorm Warning | TSA | Adair | 43 min |
| Jul 1, 10:19 AM CDT | Severe Thunderstorm Warning | TSA | Osage | 41 min |
| Jul 1, 10:44 AM CDT | Severe Thunderstorm Warning | TSA | Pawnee | 46 min |
| Jul 1, 11:25 AM CDT | Severe Thunderstorm Warning | TSA | Tulsa | 50 min |
| Jul 1, 11:29 AM CDT | Severe Thunderstorm Warning | TSA | Osage | 16 min |
| Jul 1, 11:54 AM CDT | Severe Thunderstorm Warning | TSA | Rogers, Wagoner | 51 min |
| Jul 1, 10:05 AM CDT | Severe Thunderstorm Warning | TSA | Benton | 55 min |
| Jul 1, 10:34 AM CDT | Flash Flood Warning | TSA | Benton | 116 min |
| Jul 1, 11:15 AM CDT | Flash Flood Warning | TSA | Carroll | 2 hr |
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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.