Alert archive / Oklahoma / Severe Thunderstorm Warnings in 1999
Severe Thunderstorm Warning 94, NWS Tulsa, OK
NWS Tulsa, OK issued this severe thunderstorm warning at Apr 5, 1999, 8:01 AM CDT for McIntosh County, Okmulgee County, Oklahoma. It was in force for 44 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
- Apr 5, 1999, 8:01 AM CDT (13:01 UTC)
- Expired
- Apr 5, 1999, 8:45 AM CDT
- In force
- 44 min
- Issued by
- NWS Tulsa, OK
- Area
- Whole counties; the outline is the Mesonet’s reconstruction
Counties McIntosh County, OK, Okmulgee County, OK
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Apr 5, 8:17 AM CDT | Hail 0.75 | Eufaula, OK | Location: on the Indian Nations Turnpike |
| Apr 5, 8:25 AM CDT | Thunderstorm Wind 52 | Henryetta Arpt, 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 nearest sounding before it
Lamont, OK (KLMN), launched 12:00Z, 1.0 hours before the alert went out and 194 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
- 1211 J/kg
- Mixed-layer CIN
- -3 J/kg
- Mixed-layer LCL
- 593 m above ground
- 0-6 km bulk shear
- 139 kt
- 0-1 km storm-relative helicity
- 1513 m²/s²
- 0-3 km storm-relative helicity
- 1962 m²/s²
- Significant tornado parameter
- 14.2
- Supercell composite
- 52.4
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 Apr 5, 7:50 AM CDT, 11 minutes earlier.
Area forecast discussion, Apr 5, 7:50 AM CDT, 11 minutes before
EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION NATIONAL WEATHER SERVICE TULSA OK 750 AM CDT MON APR 5 1999 WILL ISSUE UPDATE SHORTLY TO ACCOUNT FOR NEW WATCH BOX CONFIGURATION. SPC SAYS THEY WILL MONITOR ACTIVITY FURTHER SOUTH AND ISSUE WATCH LATER IF IT PERSISTS. ODDLY...INSTABILITY ANALYSIS SHOWS A MINIMUM IN THE INSTABILITY AXIS WHERE THE CURRENT CONVECTION IS THAT WE ARE WARNING ON. HOWEVER...SURFACE WINDS HAVE BACKED SLIGHTLY IN ADVANCE OF THIS ACTIVITY IN THE PAST TWO HOURS...SO SURFACE MOISTURE CONVERGENCE HAS INCREASED SOME. WITH DAYTIME HEATING...SOME INTENSIFICATION IS POSSIBLE LATER THIS MORNING. HOWEVER WITH BEST DYNAMIC LIFT IN KS/MO...BELIEVE ACTIVITY SOUTH OF NEW WATCH BOX WILL SIMPLY MAINTAIN ITSELF FOR A COUPLE MORE HOURS. FCSTID = 22 .TUL... OK...TORNADO WATCH UNTIL 200 PM CDT FOR ZONES OKZ054>058. AR...NONE.
In the hours before
Special weather statement, Apr 5, 6:05 AM CDT, 1 hour 56 minutes before
ARZ001-002-010-011-019-020-029-OKZ049-053>076-061200- EASTERN OKLAHOMA/NORTHWEST ARKANSAS HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE TULSA OK 605 AM CDT MON APR 5 1999 ...A FEW SEVERE THUNDERSTORMS ARE POSSIBLE ACROSS EASTERN OKLAHOMA AND NORTHWEST ARKANSAS THIS MORNING AND AFTERNOON... .SYNOPSIS... A STRONG UPPER LEVEL LOW PRESSURE SYSTEM OVER NORTHERN NEW MEXICO EARLY THIS MORNING WILL LIFT INTO WESTERN KANSAS BY THIS AFTERNOON. MEANWHILE...SURFACE LOW PRESSURE ACROSS NORTHWEST OKLAHOMA WILL MOVE INTO NORTHEASTERN KANSAS...WITH A DRYLINE PUSHING INTO FAR EASTERN OKLAHOMA THIS AFTERNOON. .DISCUSSION... THE AIRMASS ACROSS EASTERN OKLAHOMA REMAINS VERY MOIST AND UNSTABLE THIS MORNING...WITH SURFACE DEWPOINTS IN THE LOWER TO MID 60S. STRONG SOUTHERLY TO SOUTHEASTERLY LOW-LEVEL WINDS WILL RESULT IN CONTINUED STRONG LIFT ACROSS THE REGION. AN INITIAL BAND OF SHOWERS AND A FEW THUNDERSTORMS WILL MOVE ACROSS EASTERN OKLAHOMA EARLY THIS MORNING BETWEEN 6 AM AND 9 AM....BUT THIS ACTIVITY SHOULD REMAIN BELOW SEVERE LIMITS. MEANWHILE...A SECONDARY LINE OF THUNDERSTORMS OVER SOUTH CENTRAL OKLAHOMA EARLY THIS MORNING WILL CONTINUE TO MOVE QUICKLY NORTHEAST. THESE THUNDERSTORMS SHOULD REMAIN STRONG TO SEVERE AS THE DRYLINE PUNCHES INTO CENTRAL OKLAHOMA AND COOLER TEMPERATURES ALOFT SPREAD EAST. THIS ACTIVITY SHOULD EVENTUALLY FORM INTO A BROKEN SQUALL LINE...AND MOVE THROUGH EASTERN OKLAHOMA AFTER 9 AM AND EVENTUALLY REACH NORTHWEST ARKANSAS AROUND 11 AM. STRONG STRAIGHT-LINE WINDS WILL BE THE PRIMARY SEVERE WEATHER THREAT. THE SEVERE WEATHER THREAT SHOULD DIMINISH AFTER 2 TO 3 PM AS THE LINE OF THUNDERSTORMS MOVES FARTHER EAST INTO ARKANSAS. .EMERGENCY AGENCY AND SPOTTER ACTIVATION... STORM SPOTTER ACTIVATION MAY BE NEEDED THIS MORNING ACROSS EASTERN OKLAHOMA AND NORTHWEST ARKANSAS. AN UPDATED HAZARDOUS WEATHER OUTLOOK WILL BE ISSUED AROUND 1 PM.
Special weather statement, Apr 5, 6:05 AM CDT, 1 hour 56 minutes before
ARZ001-002-010-011-019-020-029-OKZ049-053>076-061200- EASTERN OKLAHOMA/NORTHWEST ARKANSAS HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE TULSA OK 605 AM CDT MON APR 5 1999 ...A FEW SEVERE THUNDERSTORMS ARE POSSIBLE ACROSS EASTERN OKLAHOMA AND NORTHWEST ARKANSAS THIS MORNING AND AFTERNOON... .SYNOPSIS... A STRONG UPPER LEVEL LOW PRESSURE SYSTEM OVER NORTHERN NEW MEXICO EARLY THIS MORNING WILL LIFT INTO WESTERN KANSAS BY THIS AFTERNOON. MEANWHILE...SURFACE LOW PRESSURE ACROSS NORTHWEST OKLAHOMA WILL MOVE INTO NORTHEASTERN KANSAS...WITH A DRYLINE PUSHING INTO FAR EASTERN OKLAHOMA THIS AFTERNOON. .DISCUSSION... THE AIRMASS ACROSS EASTERN OKLAHOMA REMAINS VERY MOIST AND UNSTABLE THIS MORNING...WITH SURFACE DEWPOINTS IN THE LOWER TO MID 60S. STRONG SOUTHERLY TO SOUTHEASTERLY LOW-LEVEL WINDS WILL RESULT IN CONTINUED STRONG LIFT ACROSS THE REGION. AN INITIAL BAND OF SHOWERS AND A FEW THUNDERSTORMS WILL MOVE ACROSS EASTERN OKLAHOMA EARLY THIS MORNING BETWEEN 6 AM AND 9 AM....BUT THIS ACTIVITY SHOULD REMAIN BELOW SEVERE LIMITS. MEANWHILE...A SECONDARY LINE OF THUNDERSTORMS OVER SOUTH CENTRAL OKLAHOMA EARLY THIS MORNING WILL CONTINUE TO MOVE QUICKLY NORTHEAST. THESE THUNDERSTORMS SHOULD REMAIN STRONG TO SEVERE AS THE DRYLINE PUNCHES INTO CENTRAL OKLAHOMA AND COOLER TEMPERATURES ALOFT SPREAD EAST. THIS ACTIVITY SHOULD EVENTUALLY FORM INTO A BROKEN SQUALL LINE...AND MOVE THROUGH EASTERN OKLAHOMA AFTER 9 AM AND EVENTUALLY REACH NORTHWEST ARKANSAS AROUND 11 AM. STRONG STRAIGHT-LINE WINDS WILL BE THE PRIMARY SEVERE WEATHER THREAT. THE SEVERE WEATHER THREAT SHOULD DIMINISH AFTER 2 TO 3 PM AS THE LINE OF THUNDERSTORMS MOVES FARTHER EAST INTO ARKANSAS. .EMERGENCY AGENCY AND SPOTTER ACTIVATION... STORM SPOTTER ACTIVATION MAY BE NEEDED THIS MORNING ACROSS EASTERN OKLAHOMA AND NORTHWEST ARKANSAS. AN UPDATED HAZARDOUS WEATHER OUTLOOK WILL BE ISSUED AROUND 1 PM.
The office that day
Everything else NWS Tulsa, OK issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 4, 7:10 PM CDT | Severe Thunderstorm Warning | TSA | Adair, Sequoyah | 35 min |
| Apr 4, 7:42 PM CDT | Severe Thunderstorm Warning | TSA | Adair | 33 min |
| Apr 5, 7:30 AM CDT | Severe Thunderstorm Warning | TSA | Okfuskee | 45 min |
| Apr 5, 10:51 AM CDT | Severe Thunderstorm Warning | TSA | Adair, Sequoyah | 39 min |
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.