Alert archive / Nebraska / Severe Thunderstorm Warnings in 2002
Severe Thunderstorm Warning 67, NWS Cheyenne, WY
NWS Cheyenne, WY issued this severe thunderstorm warning at Sep 7, 2002, 7:02 PM MDT for Box Butte County, Dawes County, Nebraska. It was in force for 43 min. No storm report in the archive falls inside the area while it was in force.
The area
The counties it named.
The facts
- Issued
- Sep 7, 2002, 7:02 PM MDT (01:02 UTC)
- Expired
- Sep 7, 2002, 7:45 PM MDT
- In force
- 43 min
- Issued by
- NWS Cheyenne, WY
- Area
- Counties, with a storm outline in the text
Counties Box Butte County, NE, Dawes County, NE
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 nearest sounding before it
Rapid City, SD (KUNR), launched 00:00Z, 1.0 hours before the alert went out and 179 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
- 42 J/kg
- Mixed-layer CIN
- -6 J/kg
- Mixed-layer LCL
- 3276 m above ground
- 0-6 km bulk shear
- 39 kt
- 0-1 km storm-relative helicity
- -23 m²/s²
- 0-3 km storm-relative helicity
- 18 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.0
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 Cheyenne, WY wrote its last area forecast discussion before this severe thunderstorm warning went out at Sep 7, 1:50 PM MDT, 5 hours 12 minutes earlier.
Area forecast discussion, Sep 7, 1:50 PM MDT, 5 hours 12 minutes before
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CHEYENNE WY 150 PM MDT SAT SEP 7 2002 UPR TROF OVR THE PAC NW GRDLLY LIFTING OFF TO THE NORTHEAST AND SHEARING OUT OVR THE NEXT 36-48HRS. WV IMAGERY SHOWING SUBTROPICAL MSTR PLUME CONTG ACRS THE INTERMOUNTAIN WEST. APPEARS TO BE SVRL EMBEDDED S/WV TROFS IN BROAD SW FLOW...W/ ONE EVIDENT OVR CENTRAL WY AND ANOTHER OVR UT. MODELS FAIRLY SIMILAR THRU MON...W/ SIGNIFICANT DIVERGENCE IN QPF MON NITE-TUE BETWEEN ETA AND AVN. MODEL TRENDS HAVE BEEN SLOWER W/ MSTR AXIS SHIFTING EAST THE LAST SVRL RUNS...AND THIS IS EXACTLY WHAT HAS HAPPENED. PAC FRNT MVS ACRS THE AREA SUN MORN...WITH H3 JET ENERGY SLOWLY WORKING ITS WAY INTO WY. THERE SHOULD BE INCREASING COVERAGE OF SHWRS/TSTMS ACRS THE FA SUN AFTN/EVENING GIVEN DVLPG UPSLOPE FLOW AFT FROPA...STRONGER S/WV ENERGY MVG OUT OF CO AND H3 DIVERGENCE FIELDS INCR IN ASSOC W/ H3 JET. I WL GO WITH 30-50% POPS SUN AFTN...INCRG TO 40-60% POPS SUN NIGHT. LOW LVL UPSLOPE FLOW CONTS TO BE OVERRUN BY S/WV ENERGY EMBEDDED IN SW FLOW ALF ON MONDAY. H3 JET DYNAMICS ALSO FOCUSED OVR THE FA...W/ FA IN THE RRQ OF 80KT JET. THIS WL RESULT IN HIGH SCT OR LIKELY POPS OVR MANY PARTS OF THE AREA. I WL LEAVE TSTM MENTION OUT OF THE FCST FOR MONDAY...AS SFC LI/S ARE +2 TO +4 AND MID LVL LAPSE RATES DECR TO 5-6 DEGC/KM. AVN IS SLOWER TO PUSH THE SFC FRONT SOUTH/EAST OF THE FA MON NITE-TUE...AND THEREFORE HOLDS ON TO MUCH MORE PCPN THAN THE 84HR ETAX. BELIEVE THE AVN IS SUFFERING FROM SOME FEEDBACK OR GRID SCALE PROBLEMS /PMDHMD/...AND WL LEAN TOWARD THE SOMEWHAT DRIER AND MORE REASONABLE ETAX SOLUTION. THIS PUSHES MOST OF THE PCPN INTO CO-KS...W/ BEST CHANCES OF PCPN ACRS THE FA CENTERED ACRS THE SRN 1/3 OF THE AREA. .EXTENDED... A WEAK SHORTWAVE WILL BRING A CHANCE OF AFTERNOON/EVENING THUNDERSTORMS TO THE FORECAST AREA WED. THE ASSOCIATED SURFACE COLD FRONT WILL BRING COOLER TEMPERATURES THU WITH DRYING DOWNSLOPE WINDS. A SHORTWAVE RIDGE WILL KEEP THE REGION DRY FRI AS TEMPERATURES BEGIN TO REBOUND SLOWLY. A WEAK SHORTWAVE DISTURBANCE WILL BRUSH EASTERN PORTIONS OF THE REGION SAT AND BRING A SMALL CHANCE OF SHOWERS TO PORTIONS OF THE NEB PANHANDLE. .CYS... WY...NONE. NE...NONE. JK/JMR
Nearby
Severe Thunderstorm Warnings in Nebraska, 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; the sounding from the Mesonet's radiosonde archive.