Alert archive / Texas / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 177, NWS Amarillo, TX

September 17, 2001Dallam County, Texas

NWS Amarillo, TX issued this severe thunderstorm warning at Sep 17, 2001, 5:43 PM CDT for Dallam County, Texas. It was in force for 62 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
Sep 17, 2001, 5:43 PM CDT (22:43 UTC)
Expired
Sep 17, 2001, 6:45 PM CDT
In force
62 min
Issued by
NWS Amarillo, TX
Area
Whole counties; the outline is the Mesonet’s reconstruction

County Dallam County, TX

The radar

The Amarillo radar (KAMA), 137 km from the middle of the area, began a volume at 22:53 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.

The nearest sounding before it

Amarillo Airport, TX (KAMA), launched 12:00Z, 10.7 hours before the alert went out and 138 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 2001-09-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 8 joules per kilogram.LCLLFCEL10008507005003002001001 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 2001-09-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 40 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
8 J/kg
Mixed-layer CIN
-243 J/kg
Mixed-layer LCL
1781 m above ground
0-6 km bulk shear
11 kt
0-1 km storm-relative helicity
40 m²/s²
0-3 km storm-relative helicity
-4 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.

752 
WUUS54 KAMA 172243
SVRAMA
TXC111-172345-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE AMARILLO TX
543 PM CDT MON SEP 17 2001

THE NATIONAL WEATHER SERVICE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EASTERN DALLAM COUNTY IN TEXAS

* UNTIL 645 PM CDT

* AT 543 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 18 MILES NORTHWEST OF CONLEN...OR ABOUT 20
  MILES NORTH OF DALHART...MOVING SOUTHEAST AT 20 MPH.

* SOME LOCATIONS AFFECTED BY THE STORM INCLUDE...
  CONLEN...KERRICK AND CHAMBERLIN

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

LAT...LON 3648 10260 3608 10261 3607 10219 3648 10218

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 Sep 17, 4:45 PM CDT, 58 minutes earlier.

Area forecast discussion, Sep 17, 4:45 PM CDT, 58 minutes before
TEXAS/OKLAHOMA PANHANDLES FORECAST DISCUSSION
NATIONAL WEATHER SERVICE AMARILLO TX
445 PM CDT MON SEP 17 2001

MODERATELY STRONG SHORTWAVE BEGINNING TO MOVE ACROSS THE CENTRAL
ROCKIES THIS AFTERNOON PER LATEST WV/IR IMAGERY. AT THE SURFACE...
STATIONARY FRONT WAS STRETCHED FROM NORTHERN KANSAS WESTWARD INTO
EAST CENTRAL COLORADO...WITH MESO-LOW LOCATED IN SOUTHWESTERN
KANSAS.

CONVECTION INCREASING ALONG AND TO THE NORTH OF STATIONARY FRONT AS
WELL AS THE HIGHER TERRAIN ALONG THE EASTERN SLOPES OF COLORADO AND
NORTHEASTERN NEW MEXICO. EXPECT STATIONARY FRONT TO BEGIN MOVING
SOUTH...PARTIALLY MASKED BY CONVECTIVE OUTFLOW...LATE THIS
AFTERNOON...ENTERING THE OKLAHOMA PANHANDLE DURING THE EARLY
EVENING. SHORT RANGE MODELS...AVN AND MORE SO NGM...APPEAR TOO SLOW
AND TOO FAR NORTH WITH THE FRONT. ETA SEEMS A BIT MORE REALISTIC...
HOWEVER...THIS IS BECAUSE IT MAY BE TOO FAST WITH THE SHORTWAVE.
THEREFORE...MUCH OF PACKAGE IS BASED UPON A MESHING OF THE AVN/S
MID AND UPPER LEVEL FEATURES...AND THE ETA/S LOW-LEVEL FEATURES.
STEEP LAPSE RATES...STRONG DAYTIME INSOLATION...AND INCREASING
SPEED/DIRECTIONAL SHEAR HAS CREATED VERY FAVORABLE CONDITIONS FOR
SEVERE TSRA...WITH MAIN THREAT BEING LARGE HAIL AND DAMAGING
DOWNBURST WINDS. EARLY ISOLATED CELLS MIGHT PRODUCE A TORNADO...BUT
AS THE EVENING PROGRESSES...CONVECTION LIKELY TO MERGE INTO LARGE
CLUSTERS...EVENTUALLY EVOLVING INTO MCS. THIS WILL CREATE
CONDITIONS FAVORABLE FOR LOCALLY HEAVY RAINFALL AND WILL BE
MENTIONED IN A UPCOMING UPDATE TO FORECAST. SFC FRONT WILL SHIFT
EAST TONIGHT AND ALLOW COLD FRONT TO PUSH SOUTH ACROSS THE REMAINDER
OF THE CWFA. COOLER TEMPS FOR TUESDAY AND TUESDAY NIGHT DUE TO
/SLIGHTLY/ DRIER AIRMASS AND WEAK UPSLOPE LOW-LEVEL FLOW. DESPITE
DIMINISHING SYNOPTIC SCALE LIFT FROM EXITING SHORTWAVE...WILL RETAIN
CHANCE POPS FOR TUESDAY AND TUESDAY NIGHT AS AFTERNOON CONVECTIVE
SNACKS SEEM TO SOMEHOW EMERGE ACROSS THE HIGHER TERRAIN UNDER WEST
TO NORTHWEST FLOW ALOFT AND UPSLOPE FLOW NEAR THE SURFACE.

PRECIPITATION CHANCES LOOK TO WANE THROUGH THURSDAY WITH NORTHWEST
FLOW ALOFT WEAKENING AND LOW LEVEL FOCUSING MECHANISMS APPARENTLY
ABSENT. WEAK SHORTWAVE MAY PASS TO THE NORTH OF THE AREA FRIDAY AND
FRIDAY NIGHT...PULLING ANOTHER FRONT SOUTH ACROSS THE AREA...SO
DECIDED TO RETAIN LOW POPS THEN. LOW CONFIDENCE FOR PRECIPITATION
POTENTIAL SUNDAY AND MONDAY AS MEDIUM RANGE MODELS ARE TRENDING
TOWARD UPPER LEVEL RIDGING. THEREFORE...WILL KEEP DRY AND WARM FOR
NOW.

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

JH

In the hours before

Special weather statement, Sep 17, 12:55 PM CDT, 4 hours 48 minutes before
OKZ001>003-TXZ001>020-172100-

TEXAS/OKLAHOMA PANHANDLES THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE AMARILLO TX
1255 PM CDT MON SEP 17 2001

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE ENTIRE
TEXAS AND OKLAHOMA PANHANDLES THROUGH TONIGHT.

WARM...MOIST...UNSTABLE AIR WILL BE FOUND ACROSS THE PANHANDLES THIS
AFTERNOON. A SURFACE TROUGH ACROSS EASTERN NEW MEXICO WILL MOVE EAST
INTO THE WESTERN PANHANDLES BY MID AFTERNOON.  A COLD FRONT WILL MOVE
ACROSS THE PANHANDLES TONIGHT. THE WARM...MOIST AND UNSTABLE AIRMASS
WILL BE LIFTED BY THESE SURFACE BOUNDARIES AND AN UPPER LEVEL
DISTURBANCE WILL MOVE FROM THE ROCKIES INTO THE PANHANDLES TO PROVIDE
A TRIGGER FOR THUNDERSTORM DEVELOPMENT.

THUNDERSTORMS ARE EXPECTED TO DEVELOP IN SOUTHEAST COLORADO OR
NORTHEAST NEW MEXICO BY MID AFTERNOON. THESE STORMS ARE THEN EXPECTED
TO MOVE EAST INTO PANHANDLES.  THE UNSTABLE AIR ALONG WITH THE UPPER
LEVEL ENERGY WILL PROVIDE THE STAGE FOR STRONG TO SEVERE THUNDERSTORM
DEVELOPMENT THROUGH TONIGHT. THE MAIN THREATS FROM THE STORMS WILL BE
LARGE HAIL AND VERY HEAVY RAIN. HEAVY RAIN HAS ALREADY FALLEN ACROSS
PARTS OF THE WESTERN AND CENTRAL TEXAS PANHANDLE AND THE CENTRAL
OKLAHOMA PANHANDLE OVER THE LAST COUPLE OF DAYS. MORE HEAVY RAIN WILL
ONLY AGGRAVATE THE FLASH FLOOD POTENTIAL.

ISOLATED SUPERCELLS WITH TORNADOES WILL ALSO NOT BE OUT OF THE
QUESTION AS THE WIND PROFILE ALOFT BECOMES MORE FAVORABLE THIS
AFTERNOON.

SPOTTERS AND EMERGENCY MANAGEMENT OFFICIALS SHOULD REMAIN ALERT FOR
POSSIBLE ACTIVATION THIS AFTERNOON OR EVENING.

GOEHRING

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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.