Alert archive / Texas / Severe Thunderstorm Warnings in 2002
Severe Thunderstorm Warning 18, NWS Amarillo, TX
NWS Amarillo, TX issued this severe thunderstorm warning at Apr 17, 2002, 7:20 PM CDT for Collingsworth County, Wheeler County, Texas. It was in force for 25 min. 2 reports came from inside the area while it was in force.
The area
The outline as issued, with what was reported inside it.
The facts
- Issued
- Apr 17, 2002, 7:20 PM CDT (00:20 UTC)
- Expired
- Apr 17, 2002, 7:45 PM CDT
- In force
- 25 min
- Issued by
- NWS Amarillo, TX
- Area
- Counties, with a storm outline in the text
Counties Collingsworth County, TX, Wheeler County, TX
The radar
The Amarillo radar (KAMA), 142 km from the middle of the area, began a volume at 00:23 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
| Time | Report | Where | Remark |
|---|---|---|---|
| Apr 17, 7:35 PM CDT | Hail 0.88 | Samnorwood, TX | |
| Apr 17, 7:40 PM CDT | Hail 0.75 | Shamrock, 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.
Did it verify
Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.
Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.
The watch it was issued in
The SPC watch in force over the same counties when this warning went out.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| Apr 17, 6:00 PM CDT | Tornado Watch | SPC | 5 hr |
The nearest sounding before it
Amarillo Airport, TX (KAMA), launched 00:00Z, 0.3 hours before the alert went out and 141 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
- 53 J/kg
- Mixed-layer CIN
- -53 J/kg
- Mixed-layer LCL
- 3565 m above ground
- 0-6 km bulk shear
- 50 kt
- 0-1 km storm-relative helicity
- 33 m²/s²
- 0-3 km storm-relative helicity
- 63 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.1
The text
As transmitted, in the capitals the NWS used until 2016.
000 WUUS54 KAMA 180020 SVRAMA TXC087-483-180045- BULLETIN - EAS ACTIVATION REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE AMARILLO TX 720 PM CDT WED APR 17 2002 THE NATIONAL WEATHER SERVICE IN AMARILLO HAS ISSUED A * SEVERE THUNDERSTORM WARNING FOR... SOUTHEASTERN WHEELER COUNTY IN THE TEXAS PANHANDLE NORTHEASTERN COLLINGSWORTH COUNTY IN THE TEXAS PANHANDLE * UNTIL 745 PM CDT * AT 720 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM 12 MILES SOUTHEAST OF SHAMROCK...MOVING NORTH AT 30 MPH. * SOME LOCATIONS AFFECTED BY THE STORM INCLUDE... SHAMROCK LARGE HAIL...DAMAGING WINDS...AND TORRENTIAL RAINS ARE EXPECTED WITH THIS STORM. TAKE COVER IN A SUBSTANTIAL SHELTER. LAT...LON 3515 10031 3495 10002 3547 10001 3548 10007
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 17, 4:45 PM CDT, 2 hours 35 minutes earlier.
Area forecast discussion, Apr 17, 4:45 PM CDT, 2 hours 35 minutes before
TEXAS/OKLAHOMA PANHANDLES FORECAST DISCUSSION NATIONAL WEATHER SERVICE AMARILLO TX 445 PM CDT WED APR 17 2002 BAND OF MID/UPPER LEVEL SUB-TROPICAL MOISTURE WAS STREAMING NORTHEAST OVER SOUTHERN PLAINS THIS AFTERNOON AS VARIOUS VORTICITY LOBES ROTATED AROUND WESTERN U.S. TROUGH. ONE LOBE WAS MOVING OVER SOUTHERN NV AND SOUTHERN UT AS OF MID-AFTERNOON AND IS LIKELY AIDING THE SURFACE CYCLOGENESIS IN WY. MEANWHILE...SLOWLY RETREATING DRYLINE WAS SHARPENING UP FROM NEAR KGAG SOUTHWEST TO NEAR TULIA. ISOLD CONVECTION HAD INITIATED IN ZONE OF STRONGEST CONVERGENCE FROM WESTERN OK INTO THE SOUTHEASTERN TX PNHDL. HOWEVER...STORMS ARE STILL STRUGGLING TO MAINTAIN ORGANIZATION DUE TO STRONG MID/UPPER LEVEL SHEAR AND STRENGTHENING CAP. THEREFORE...DECIDED TO MENTION TSRA FOR EAST CENTRAL AND SOUTHEASTERN TX PNHDL...BUT NEXT SHIFT MAY NEED TO INCLUDE NORTHEAST TX PNHDL AND EASTERN OK PNHDL IF DRYLINE CONTINUES TO RETREAT. SHORT RANGE MODELS ARE IN MODERATE AGREEMENT THROUGH NEXT 48 TO 60 HRS...MORE SO ALOFT AND LESS SO NEAR THE SURFACE. ETA IS MORE AGGRESSIVE THAN AVN IN NEXT FRONT PUSHING SOUTH INTO THE PNHDLS BY FRIDAY MORNING. QUESTION STILL REMAINS ABOUT HOW FAR IT WILL GO. AS TIME MOVES FURTHER INTO SPRING...COLD FRONTS HAVE A HARD TIME BARRELING THROUGH THE AREA UNLESS THEY ARE AIDED BY A VERY COLD AIRMASS AND/OR HAVE A MODERATE AMOUNT OF CONVECTION ASSOCIATED WITH IT. SHORT RANGE AND MEDIUM RANGE MODELS INDICATING THAT UPPER LEVEL TROUGH SHOULD STAY OUT WEST AND BECOME POSITIVELY TILTED BY THE END OF THE WEEK THEN BEGIN TO SHEAR OUT DURING THE WEEKEND. THEREFORE... DECIDED TO EXPAND TSRA POPS TEMPORALLY ACROSS THE AREA BACK INTO FRIDAY AFTN AND INTO SUNDAY. LOWERING HEIGHTS AND NEAR ZONAL FLOW ALOFT WILL RETURN EARLY NEXT WEEK ALONG WITH DEVELOPING TROUGH. POSSIBLE DRYLINE REDEVELOPMENT BY THE MIDDLE OF NEXT WEEK. FOR NOW WILL CONTINUE WITH SLIGHTLY COOLER TEMPERATURES AND PARTLY CLOUDY SKIES. FINAL NUMBERS... AMA UE 054/084 048/074 045 00022 DHT UE 052/083 046/070 041 00022 .AMA... TX...NONE. OK...NONE. JH
The office that day
Everything else NWS Amarillo, TX issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 17, 7:45 PM CDT | Severe Thunderstorm Warning | AMA | Donley | 60 min |
| Apr 17, 8:41 PM CDT | Severe Thunderstorm Warning | AMA | Donley | 64 min |
| Apr 17, 9:05 PM CDT | Severe Thunderstorm Warning | AMA | Collingsworth | 55 min |
Nearby
Severe Thunderstorm Warnings in Texas, 2002Every severe thunderstorm warning in 2002
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.