Alert archive / Oklahoma / Tornado Warnings in 1999

Tornado Warning 21, NWS Norman, OK

April 5, 1999Alfalfa County, Major County, Oklahoma

NWS Norman, OK issued this tornado warning at Apr 5, 1999, 5:11 AM CDT for Alfalfa County, Major County, Oklahoma. It was in force for 34 min. No storm report in the archive falls 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.

The facts

Issued
Apr 5, 1999, 5:11 AM CDT (10:11 UTC)
Expired
Apr 5, 1999, 5:45 AM CDT
In force
34 min
Issued by
NWS Norman, OK
Area
Whole counties; the outline is the Mesonet’s reconstruction

Counties Alfalfa County, OK, Major County, OK

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Apr 5, 3:45 AM CDTTornado WatchSPC5 hr
Apr 5, 3:45 AM CDTTornado WatchSPC5 hr

The nearest sounding before it

Norman, OK (KOUN), launched 00:00Z, 10.2 hours before the alert went out and 153 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.

Skew-T log-pSkew-T log-p diagram, Norman, OK at 00:00Z on 1999-04-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Norman, OK at 00:00Z on 1999-04-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 132 square meters per square second.1939587897Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2677 m above ground
0-6 km bulk shear
57 kt
0-1 km storm-relative helicity
132 m²/s²
0-3 km storm-relative helicity
346 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.3

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

999 
WFUS1 KOKC 051014 RRA
TOROKC
OKC003-093-051045-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE NORMAN OK
511 AM CDT MON APR 5 1999

THE NATIONAL WEATHER SERVICE IN NORMAN HAS ISSUED A

* TORNADO WARNING FOR...
  SOUTHERN ALFALFA COUNTY IN NORTHWEST OKLAHOMA
  EASTERN MAJOR COUNTY IN NORTHWEST OKLAHOMA

* UNTIL 545 AM CDT

* AT 511 AM CDT...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM
  CAPABLE OF PRODUCING A TORNADO. THE MOST DANGEROUS PORTION OF THE
  STORM WAS LOCATED 2 MILES WEST OF AMES...MOVING NORTH AT 50 MPH.
 
  A FUNNEL CLOUD WAS REPORTED WITH THIS STORM BY SPOTTERS AT 507 AM
  CDT NEAR AMES.

* LOCATIONS IN THE WARNING INCLUDE AMES...GOLTRY...HELENA...MENO AND
  RINGWOOD

TAKE COVER NOW ABANDON MOBILE HOMES AND VEHICLES. MOVE TO AN 
INTERIOR ROOM OR HALLWAY ON THE LOWEST FLOOR. STAY AWAY FROM WINDOWS.

TORNADOES ARE ESPECIALLY DANGEROUS AT NIGHT BECAUSE THEY ARE HARD TO
SEE. TAKE COVER NOW. IF A BASEMENT IS NOT AVAILABLE...MOVE TO AN
INTERIOR ROOM OR HALLWAY ON THE LOWEST FLOOR. LEAVE MOBILE HOMES AND
VEHICLES FOR REINFORCED SHELTER. STAY AWAY FROM WINDOWS.

LAT...LON 3624 9841 3622 9817 3662 9809 3665 9834

 MILLER

The office that day

Everything else NWS Norman, OK issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 5, 12:32 AM CDTSevere Thunderstorm WarningOUNEllis, Harper43 min
Apr 5, 1:27 AM CDTSevere Thunderstorm WarningOUNHarper48 min
Apr 5, 1:55 AM CDTSevere Thunderstorm WarningOUNWoods35 min
Apr 5, 2:24 AM CDTTornado WarningOUNGreer36 min
Apr 5, 2:39 AM CDTSevere Thunderstorm WarningOUNWoodward36 min
Apr 5, 2:48 AM CDTSevere Thunderstorm WarningOUNTillman42 min
Apr 5, 2:54 AM CDTTornado WarningOUNBeckham, Custer, Roger Mills36 min
Apr 5, 3:00 AM CDTSevere Thunderstorm WarningOUNWoods, Woodward45 min
Apr 5, 3:08 AM CDTTornado WarningOUNDewey, Woodward37 min
Apr 5, 3:13 AM CDTTornado WarningOUNWoods32 min
Apr 5, 3:19 AM CDTSevere Thunderstorm WarningOUNKiowa, Washita41 min
Apr 5, 3:19 AM CDTSevere Thunderstorm WarningOUNCuster41 min
Apr 5, 3:29 AM CDTTornado WarningOUNMajor, Woods, Woodward31 min
Apr 5, 3:49 AM CDTSevere Thunderstorm WarningOUNDewey, Major41 min
Apr 5, 3:51 AM CDTSevere Thunderstorm WarningOUNAlfalfa, Woods29 min
Apr 5, 4:00 AM CDTTornado WarningOUNBlaine, Dewey, Major30 min
Apr 5, 4:02 AM CDTTornado WarningOUNAlfalfa, Woods28 min
Apr 5, 4:24 AM CDTTornado WarningOUNAlfalfa, Major36 min
Apr 5, 4:56 AM CDTTornado WarningOUNAlfalfa19 min
Apr 5, 5:03 AM CDTSevere Thunderstorm WarningOUNAlfalfa, Major27 min
Apr 5, 5:25 AM CDTTornado WarningOUNGrant20 min
Apr 5, 5:31 AM CDTTornado WarningOUNAlfalfa, Garfield, Grant29 min
Apr 5, 5:42 AM CDTSevere Thunderstorm WarningOUNGarvin, Grady, McClain, Stephens48 min
Apr 5, 5:42 AM CDTSevere Thunderstorm WarningOUNJefferson48 min
Apr 5, 5:53 AM CDTTornado WarningOUNGrant32 min
Apr 5, 6:17 AM CDTSevere Thunderstorm WarningOUNCleveland28 min
Apr 5, 6:28 AM CDTSevere Thunderstorm WarningOUNGarvin, McClain32 min
Apr 5, 6:42 AM CDTSevere Thunderstorm WarningOUNPottawatomie48 min
Apr 5, 7:03 AM CDTSevere Thunderstorm WarningOUNPontotoc, Seminole42 min
Apr 5, 7:32 AM CDTSevere Thunderstorm WarningOUNHughes43 min
Apr 5, 7:57 AM CDTTornado WarningOUNHughes23 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; the sounding from the Mesonet's radiosonde archive.