Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 46, NWS Tulsa, OK

April 11, 2001Okfuskee County, Okmulgee County, Oklahoma

NWS Tulsa, OK issued this severe thunderstorm warning at Apr 11, 2001, 5:22 AM CDT for Okfuskee County, Okmulgee County, Oklahoma. It was in force for 53 min. 3 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
Apr 11, 2001, 5:22 AM CDT (10:22 UTC)
Expired
Apr 11, 2001, 6:15 AM CDT
In force
53 min
Issued by
NWS Tulsa, OK
Area
Whole counties; the outline is the Mesonet’s reconstruction

Counties Okfuskee County, OK, Okmulgee County, OK

The radar

The Norman radar (KTLX), 124 km from the middle of the area, began a volume at 10:23 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

TimeReportWhereRemark
Apr 11, 5:25 AM CDTTornado F2Coalgate, OKThis tornado formed 4 miles southeast of Coalgate and tracked northeastward for 8 miles before crossing into northwest Atoka County at 0434 CST (See following entry for information about the Atoka County segment). The tornado then continued for another 5 miles
Apr 11, 5:34 AM CDTTornado F0Wardville, OKThis is the 2nd and final county segment to the tornado which formed 4 miles southeast of Coalgate in Coal County at 0425 CST, then moved into Atoka County at 0434 CST. In Atoka County, minor roof damage was sustained to a mobile home, and numerous trees were
Apr 11, 5:40 AM CDTThunderstorm WindHenryetta, OKThunderstorm wind blew down large tree limbs.

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.

IssuedProductOfficeLasted
Apr 11, 3:15 AM CDTTornado WatchSPC5 hr

The nearest sounding before it

Norman, OK (KOUN), launched 00:00Z, 10.4 hours before the alert went out and 129 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 2001-04-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1767 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Norman, OK at 00:00Z on 2001-04-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 114 square meters per square second.1939587897117136Sfc1 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
1767 J/kg
Mixed-layer CIN
-45 J/kg
Mixed-layer LCL
678 m above ground
0-6 km bulk shear
63 kt
0-1 km storm-relative helicity
114 m²/s²
0-3 km storm-relative helicity
192 m²/s²
Significant tornado parameter
1.0
Supercell composite
3.8

Open this sounding in Storm Lab

The text

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

000 
WUUS54 KTSA 111024
SVRTUL
OKC091-107-111-121-111115-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TULSA OK
522 AM CDT WED APR 11 2001

THE NATIONAL WEATHER SERVICE IN TULSA HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR
  SOUTHEASTERN OKFUSKEE COUNTY IN EAST CENTRAL OKLAHOMA
  SOUTHERN OKMULGEE COUNTY IN NORTHEAST OKLAHOMA
  MCINTOSH COUNTY IN SOUTHEAST OKLAHOMA
  PITTSBURG COUNTY IN SOUTHEAST OKLAHOMA

* UNTIL 615 AM CDT

* AT 522 AM CDT SEVERE THUNDERSTORMS CAPABLE OF PRODUCING WINDS UP TO
  70 MPH WERE LOCATED ALONG A LINE EXTENDING FROM 5 MILES NORTH
  OF LAMAR TO 6 MILES WEST OF WARDVILLE TO 2 MILES NORTHEAST OF
  ROBERTA...MOVING NORTHEAST AT 35 MPH.

* SOME LOCATIONS AFFECTED INCLUDE... CANADIAN...INDIANOLA...
  CROWDER...SCIPIO...KREBS...ALDERSON...HAYWOOD...SAVANNA...
  ASHLAND...BLANCO...KIOWA...MCALESTER...STIDHAM...VIVIAN...
  RAIFORD...HANNA...SCHULTER...GRAYSON...HOFFMAN...DEWAR...
  HENRYETTA...PHAROAH...CLEARVIEW AND WELEETKA.

DAMAGING WINDS ARE LIKELY WITH THESE STORMS...MOVE TO A SAFE PLACE
NOW.

A TORNADO WATCH IS ALSO IN EFFECT. TORNADOES CAN DEVELOP SUDDENLY
FROM SEVERE THUNDERSTORMS. BE ALERT F OR RAPIDLY CHANGING WEATHER
CONDITIONS.

LAT...LON 3534 9632 3457 9623 3380 9638 3419 9583
          3495 9560 3568 9574

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 11, 3:55 AM CDT, 1 hour 27 minutes earlier.

Area forecast discussion, Apr 11, 3:55 AM CDT, 1 hour 27 minutes before
EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TULSA OK
355 AM CDT WED APR 11 2001

RUNNING A BIT BEHIND THIS MORNING...

LARGE RAIN SHIELD WITH EMBEDDED SEVERE THUNDERSTORMS IS CURRENTLY
MOVING THROUGH ERN OK...WITH ADDITIONAL ACTIVITY FARTHER W ALONG
DRYLINE.  VAD WIND PROFILES SHOWING MARGINAL DIRECTION SHEAR...ALTHO
SPEED SHEAR IS IMPRESSIVE.  CHANCE OF SEVERE STORMS WILL CONTINUE
INTO THE MORNING...WITH ACTIVITY EXITING ERN EXTENT OF FORECAST AREA
14-16Z.  WILL USE RADAR FOR FINAL 1ST PERIOD POPS.

INTENSE 982MB SFC CYCLONE WILL LIFT INTO NE TODAY...WITH PRESSURE
GRADIENT TIGHTENING ACROSS THE AREA.  DEEP LAYERED MIXING WILL HELP
BRING DOWN GUSTY SWLY WINDS TO THE SFC...AND WILL GO WITH A WIND
ADVISORY FOR ALL ZONES TODAY.

MUCH DRIER LOW-LEVEL AIR WILL FILTER EWD LATER TODAY AND TONIGHT.
WINDS WILL SLACK OFF TONIGHT...SO THE STRING OF 5 RECORD HIGH LOWS
WILL END AT TULSA WITH MORE SEASONABLE TEMPS ON TAP.

REMAINDER OF WEEK LOOKS SEASONABLE AND DRY.

ZONAL FLOW WILL PERSIST THROUGH THE WEEKEND...WITH SEVERAL
FAST-MOVING/IMPOSSIBLE-TO-TIME WAVES PASSING ACROSS THE FORECAST
AREA.  AVN WANTS TO BRING LOW-LEVEL MOISTURE BACK ON SAT AHEAD OF
STRENGTHENING SFC LOW OVER WRN TX.  WILL KEEP LOW CHANCE POPS IN FOR
SAT AND SUN.

FCSTID = 18

PRELIM NUMBERS...
TUL   74  49  77  53 /  50   0   0  10
FSM   78  50  82  55 /  70   0   0  10
MLC   76  49  81  57 /  50   0   0  10
BVO   74  48  77  52 /  50   0   0  10
FYV   74  47  76  52 /  70   0   0  10
BYV   74  47  76  52 /  70   0   0  10
MIO   74  47  76  52 /  70   0   0  10
MKO   74  49  77  53 /  50   0   0  10
F10   74  49  77  53 /  50   0   0  10
HHW   76  51  81  58 /  60   0   0  10

.TSA...
AR...WIND ADVISORY FOR WEDNESDAY FOR ZONES ARZ001>002...ARZ010>011...
ARZ019>020...ARZ029.

OK...TORNADO WATCH UNTIL 800 AM CDT FOR ZONES
OKZ054>057...OKZ059>062...OKZ064>067...OKZ070>071...OKZ073.

WIND ADVISORY FOR WEDNESDAY FOR ZONES OKZ049...OKZ053>076.

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 11, 5:22 AM CDTSevere Thunderstorm WarningTSAMcIntosh, Pittsburg53 min
Apr 11, 5:55 AM CDTSevere Thunderstorm WarningTSAChoctaw, Pushmataha50 min
Apr 11, 6:14 AM CDTSevere Thunderstorm WarningTSAHaskell, Latimer, Pittsburg46 min
Apr 11, 6:14 AM CDTSevere Thunderstorm WarningTSAMcIntosh46 min
Apr 11, 6:40 AM CDTSevere Thunderstorm WarningTSAChoctaw, Pushmataha65 min
Apr 11, 6:53 AM CDTSevere Thunderstorm WarningTSAHaskell, Muskogee, Sequoyah52 min
Apr 11, 6:53 AM CDTSevere Thunderstorm WarningTSAMcIntosh52 min
Apr 11, 6:53 AM CDTSevere Thunderstorm WarningTSALatimer52 min
Apr 11, 7:20 AM CDTSevere Thunderstorm WarningTSAMayes, Wagoner40 min
Apr 11, 7:26 AM CDTSevere Thunderstorm WarningTSALeFlore64 min
Apr 11, 7:28 AM CDTTornado WarningTSAHaskell, Sequoyah47 min
Apr 11, 7:33 AM CDTSevere Thunderstorm WarningTSACherokee27 min
Apr 11, 7:44 AM CDTSevere Thunderstorm WarningTSASequoyah46 min
Apr 11, 7:53 AM CDTSevere Thunderstorm WarningTSAAdair, Cherokee, Delaware52 min
Apr 11, 7:53 AM CDTSevere Thunderstorm WarningTSACraig, Mayes, Ottawa52 min
Apr 11, 8:27 AM CDTSevere Thunderstorm WarningTSALeFlore63 min

Nearby

Severe Thunderstorm Warnings in Oklahoma, 2001Every severe thunderstorm warning in 2001

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.