Alert archive / Texas / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 36, NWS Amarillo, TX

April 21, 2001Donley County, Texas

NWS Amarillo, TX issued this severe thunderstorm warning at Apr 21, 2001, 5:39 PM CDT for Donley County, Texas. It was in force for 66 min. 2 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 21, 2001, 5:39 PM CDT (22:39 UTC)
Expired
Apr 21, 2001, 6:45 PM CDT
In force
66 min
Issued by
NWS Amarillo, TX
Area
Whole counties; the outline is the Mesonet’s reconstruction

County Donley County, TX

The radar

The Amarillo radar (KAMA), 82 km from the middle of the area, began a volume at 22:42 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 21, 5:55 PM CDTHail 1Clarendon, TX
Apr 21, 5:59 PM CDTHail 0.75Howardwick, TX

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 21, 5:30 PM CDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Amarillo Airport, TX (KAMA), launched 12:00Z, 10.7 hours before the alert went out and 81 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, Amarillo Airport, TX at 12:00Z on 2001-04-21Temperature 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, Amarillo Airport, TX at 12:00Z on 2001-04-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 0 square meters per square second.1939Sfc1 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
4057 m above ground
0-6 km bulk shear
0 kt
0-1 km storm-relative helicity
0 m²/s²
0-3 km storm-relative helicity
0 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

385 
WUUS54 KAMA 212240
SVRAMA
TXC129-212345-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE AMARILLO TX
539 PM CDT SAT APR 21 2001

THE NATIONAL WEATHER SERVICE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  DONLEY COUNTY IN THE TEXAS PANHANDLE

* UNTIL 645 PM CDT

* AT 539 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 10 MILES SOUTHWEST OF CLARENDON...MOVING
  NORTHEAST AT 45 MPH.

* SOME LOCATIONS AFFECTED BY THE STORM INCLUDE...
  CLARENDON...GREENBELT LAKE...HEDLEY...HOWARDWICK AND LELIA LAKE

LARGE HAIL...DAMAGING WINDS...AND TORRENTIAL RAINS ARE EXPECTED WITH
THIS STORM. TAKE COVER IN A SUBSTANTIAL SHELTER.

LAT...LON 3477 10109 3478 10062 3515 10060 3517 10105

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 Amarillo, TX wrote its last area forecast discussion before this severe thunderstorm warning went out at Apr 21, 2:44 PM CDT, 2 hours 55 minutes earlier.

Area forecast discussion, Apr 21, 2:44 PM CDT, 2 hours 55 minutes before
TEXAS/OKLAHOMA PANHANDLES FORECAST DISCUSSION
NATIONAL WEATHER SERVICE AMARILLO TX
244 PM CDT SAT APR 21 2001

ATMOSPHERE IS GETTING QUITE UNSTABLE EAST OF THE DRYLINE IN
WESTERN OKLAHOMA AND THE EASTERN TEXAS AND OKLAHOMA PANHANDLES.
SURFACE COLD FRONT STILL LIES ACROSS THE NORTHERN TEXAS PANHANDLE.
THIS BOUNDARY IS SHOWING SOME SIGNS OF MOVING NORTHWARD AS BGD HAS
NOW SWITCHED AROUND TO THE SOUTHWEST. WOULD NOT BE SURPRISED TO SEE
THE DRYLINE AND THE INTERSECTION BETWEEN THE COLD FRONT AND DRYLINE
SET OFF A FEW STORMS THIS AFTERNOON. STORMS COULD QUICKLY BECOME
SEVERE AS STRONG INSTABILITY BREAKS THROUGH WHAT CAP THERE IS.

STRONG TO SEVERE STORMS ARE EXPECTED ACROSS MUCH OF THE PANHANDLES
OVERNIGHT AS LOW LEVEL JET COMBINES WITH UPPER LOW PUSHING EAST
ACROSS NEW MEXICO. PLENTY OF MOISTURE WILL BE BROUGHT BACK TO THE
WESTERN ZONES TO MEET UP WITH THE DYNAMICS COMING OUT OF THE
ROCKIES. WILL GO WITH HIGHEST POPS TONIGHT AHEAD OF DYNAMICS.
DRYLINE TEAMS UP WITH PACIFIC COLD FRONT LATE TONIGHT AND DRIVES
EAST...SO WILL TAPER OFF POPS TO THE WEST ON SUNDAY AS THE SYSTEM
MOVES INTO THE CENTRAL HIGH PLAINS.  STORMS SHOULD MOVE EAST AND
NORTHEAST QUICKLY AS WINDS ALOFT INCREASE WITH JET STREAK AROUND
THE EASTERN SIDE OF THE UPPER LOW.

MODELS MAY BE CATCHING ON TO THE COLD AIR BEHIND THE FRONT WHICH
MOVES THROUGH SUNDAY NIGHT. WE WILL LOWER SOME TEMPERATURES FOR
MONDAY WITH THIS IN MIND.

UPPER LEVEL RIDGE STARTS TO BUILD BACK ACROSS THE ROCKIES THROUGH
MID WEEK...SO WARMER TEMPERATURES LOOK TO BE ON TRACK. WE WILL
INSERT SOME SLIGHT CHANCE POPS FOR THE WEST AND CENTRAL ON THURSDAY
AND FRIDAY. SEVERAL RIPPLES (SHORT WAVES) MOVE THROUGH THE MEAN
RIDGE OVER THE ROCKIES/HIGH PLAINS IN THE SOUTHERN STREAM. SOME
CONVECTION MAY FORM ALONG THE ROCKIES AND MOVE INTO THE AREA.  WILL
LEAVE SATURDAY DRY FOR NOW AS RIDGE AXIS MOVES ACROSS THE
PANHANDLES AHEAD OF NEXT STRONG UPPER LOW ALONG THE WEST COAST.

WE USED A BLEND OF THE MODELS FOR THIS FORECAST. THE ETA HAD A
BETTER HANDLE ON THE SURFACE...WHILE THE AVN HAD A BETTER HANDLE ON
THE UPPER AIR FEATURES.

A FEW NUMBERS TO PONDER:

DHT 51/71 38/64 36 730
AMA 57/74 40/66 39 750
BVR 60/79 45/65 39 660

.AMA...
TX...NONE.
OK...NONE.

GOEHRING

In the hours before

Special weather statement, Apr 21, 1:09 PM CDT, 4 hours 30 minutes before
OKZ001>003-TXZ001>020-220500-

TEXAS/OKLAHOMA PANHANDLES THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE AMARILLO TX
109 PM CDT SAT APR 21 2001

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS LATE THIS AFTERNOON
AND ESPECIALLY TONIGHT ACROSS ALL OF THE OKLAHOMA AND TEXAS
PANHANDLES.

A COLD FRONT WAS LOCATED OVER SOUTHEAST COLORADO AND SOUTHERN KANSAS
EARLY THIS AFTERNOON. AT THIS TIME...THE COLD FRONT IS EXPECTED TO
REMAIN JUST TO THE NORTH OF THE OKLAHOMA PANHANDLE THROUGH TONIGHT.
MEANWHILE...THE DRYLINE WAS LOCATED OVER EASTERN SECTIONS OF THE
OKLAHOMA AND TEXAS PANHANDLES. THIS FEATURE IS EXPECTED TO MOVE BACK
TO THE WESTERN SECTIONS OF THE PANHANDLES BEGINNING LATE THIS
AFTERNOON THROUGH THE EVENING HOURS.

A VIGOROUS UPPER LEVEL LOW PRESSURE SYSTEM CURRENTLY MOVING THROUGH
SOUTHERN CALIFORNIA AND NEVADA IS FORECAST TO TRACK EASTWARD INTO
NORTHERN NEW MEXICO BY EARLY SUNDAY MORNING. MOISTURE WILL CONTINUE
TO INCREASE AHEAD OF THIS DISTURBANCE THROUGH TONIGHT. ALL THIS WILL
SET THE STAGE FOR THE DEVELOPMENT OF THUNDERSTORMS.

ISOLATED THUNDERSTORMS MAY FORM ALONG AND AHEAD OF THE DRYLINE OVER
THE EASTERN OKLAHOMA AND EASTERN TEXAS PANHANDLES LATE THIS
AFTERNOON INTO THE EARLY EVENING. HOWEVER...THE GREATEST THREAT FOR
MORE WIDESPREAD THUNDERSTORMS IS EXPECTED TO OCCUR LATER TONIGHT
INTO EARLY SUNDAY MORNING. ANY THUNDERSTORMS WHICH DEVELOP WILL HAVE
THE POTENTIAL TO BECOME SEVERE AS THEY MOVE RAPIDLY TO THE NORTHEAST.
THE MAIN SEVERE WEATHER THREATS WILL BE DAMAGING WINDS AND LARGE
HAIL. ATMOSPHERIC WIND PROFILES ARE FORECAST TO BECOME MORE FAVORABLE
LATER TODAY AND TONIGHT TO SUPPORT THE DEVELOPMENT OF ISOLATED
TORNADOES...ESPECIALLY ALONG AND EAST OF A LINE EXTENDING FROM
GUYMON OKLAHOMA TO AMARILLO TEXAS.

SPOTTER GROUPS AND EMERGENCY MANAGEMENT OFFICIALS ACROSS ALL OF THE
OKLAHOMA AND TEXAS PANHANDLES SHOULD REMAIN ALERT FOR LIKELY
ACTIVATION LATER THIS AFTER,NOON OR TONIGHT.

ANDRADE

The office that day

Everything else NWS Amarillo, TX issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 21, 6:49 PM CDTSevere Thunderstorm WarningAMADonley41 min

Nearby

Severe Thunderstorm Warnings in Texas, 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.