Alert archive / Wyoming / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 89, NWS Billings, MT

July 18, 2002Sheridan County, Wyoming

NWS Billings, MT issued this severe thunderstorm warning at Jul 18, 2002, 12:23 AM MDT for Sheridan County, Wyoming. It was in force for 57 min. 1 report came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued: Jul 18, 2002, 12:23 AM MDT (06:23 UTC)
Expired: Jul 18, 2002, 1:20 AM MDT
In force: 57 min
Issued by: NWS Billings, MT
Area: Whole counties

County Sheridan County, WY

The radar

The Billings radar (KBLX), 180 km from the middle of the area, began a volume at 06:22 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
Jul 18, 12:45 AM MDT	Thunderstorm Wind 60 E	Leiter, WY

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 nearest sounding before it

Riverton, WY (KRIW), launched 00:00Z, 6.4 hours before the alert went out and 227 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 799 J/kg
Mixed-layer CIN: -5 J/kg
Mixed-layer LCL: 3088 m above ground
0-6 km bulk shear: 27 kt
0-1 km storm-relative helicity: -2 m²/s²
0-3 km storm-relative helicity: 79 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.1

Open this sounding in Storm Lab

The text

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

000 
WUUS55 KBYZ 180623
SVRBYZ
WYC033-180720-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE BILLINGS MT
1221 AM MDT THU JUL 18 2002

THE NATIONAL WEATHER SERVICE IN BILLINGS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SHERIDAN COUNTY IN NORTH CENTRAL WYOMING
  THIS INCLUDES THE CITY OF SHERIDAN

* UNTIL 120 AM MDT

* AT 1221 AM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 25 MILES SOUTH OF SHERIDAN...OR ABOUT 5        
  MILES NORTH OF BUFFALO...MOVING NORTH AT 30 MPH. THIS STORM HAS A
  HISTORY OF PRODUCING 60 MPH WINDS.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
   CLEARMONT BY 1230 AM MDT.
   SHERIDAN BY 1245 AM MDT.

$$

LAT...LON 4456 10603 4456 10711 4499 10713 4500 10602

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 Billings, MT wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 17, 8:57 PM MDT, 3 hours 26 minutes earlier.

Area forecast discussion, Jul 17, 8:57 PM MDT, 3 hours 26 minutes before

SOUTH CENTRAL AND SOUTHEAST MONTANA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BILLINGS MT
857 PM MDT WED JUL 17 2002

.SHORT TERM...VALID FOR THU...FRI...SAT...

UPDATE TO ZFP ONLY...MOIST MONSOONAL FLOW CONTINUING TO BRING
MOISTURE INTO MONTANA FROM MEXICO. SMALL DISTURBANCES IN THIS FLOW
RESPONSIBLE FOR THIS EVENINGS CONVECTION. HAVE HAD REPORTS OF SEVERE
WIND GUSTS OVER BIG HORN COUNTY...BUT MAIN FEATURE WITH THESE STORMS HAS
BEEN HEAVY RAINFALL DUE TO HIGH AVAILABLE MOISTURE AND SLOW MOVEMENT.
TEMP FORECAST LOOKS GOOD WITH LOWS VERY CLOSE TO LAST NIGHTS VALUES...
HAVE UPDATED POPS FOR CURRENT CONVECTION AND TO LEAVE SLIGHT CHANCE POPS
INTO THE SOUTHWEST ZONES WHERE META SHOWING SOME LINGERING VORTICITY.
OTHERWISE SHOULD SEE MAJORITY OF THE CONVECTION COME TO AN END BY 3 AM.
CHAMBERS

.LONG TERM...VALID FOR SUN...MON...TUE...WED...
FRIDAY NIGHT AND SATURDAY...SHORTWAVE TROUGH PUSHES THROUGH MONTANA
FRIDAY NIGHT WITH ASSOCIATED COOL FRONT AT SURFACE. WITH TRAJECTORY OF
ENERGY BEST SHOT FOR THUNDER APPEARS TO BE IN THE WEST. SATURDAY COOL
FRONT PUSHES INTO DAKOTAS BUT AVN DEVELOPING DECENT INSTABILITY OUT EAST
IN THE AFTERNOON AND EVENING. WILL TWEAK POPS FOR BOTH PERIODS
ACCORDINGLY.
WEST TO NORTHWEST UPPER FLOW DEVELOPS THROUGH THE
EXTENDED PERIOD. SOME DIFFERENCES ON AMPLITUDE AND POSITION OF UPPER
RIDGE OVER THE WEST. MRF MORE AMPLIFIED WITH RIDGE THUS PUTS MONTANA IN
MORE NORTHWEST UPPER FLOW...WHILE UKMET AND ECMWF KEEPING FLOW MORE
ZONAL. IN EITHER CASE TEMPS SHOULD BE NEAR SEASONAL AVERAGES AS HOT
DESERT AIRMASS IS CONFINED TO THE SOUTHWEST UNITED STATES. SHORTWAVE
ENERGY LOOKS TO STAY MAINLY TO THE NORTH OF THE AREA. AVN RUN SHOWING
COOL FRONT PASSAGE BOTH LATE SUNDAY AND TUESDAY...BUT FOR NOW WILL
CONTINUE WITH DRY FORECAST AS LITTLE UPPER LEVEL SUPPORT EVIDENT. JZ

    THU     FRI     SAT     SUN     MON     TUE     WED
-----------------------------------------------------------
BIL 065/092 068/096 064/087 063/088 062/087 060/087 061/085
    33/T    34/T    43/T    30/B    00/B    00/B    00/B
LVM 057/094 057/091 056/085 056/085 054/086 053/085 054/085
    33/T    34/T    42/T    20/B    00/B    00/B    00/B
HDN 061/094 064/098 065/087 064/089 061/089 059/088 062/086
    63/T    33/T    33/T    30/B    00/B    00/B    00/B
MLS 068/096 071/099 066/088 066/088 065/088 062/087 064/085
    42/T    23/T    33/T    30/B    00/B    00/B    00/B
4BQ 066/096 069/098 065/088 065/089 063/089 061/087 062/086
    43/T    33/T    33/T    30/B    00/B    00/B    00/B
BHK 064/092 067/097 064/085 065/086 063/087 059/085 060/083
    22/T    23/T    33/T    30/B    00/B    00/B    00/B
SHR 064/093 067/096 059/087 060/088 058/088 059/087 059/087
    33/T    33/T    33/T    30/B    00/B    00/B    00/B

.BYZ...
MT...NONE.
WY...NONE.

In the hours before

Local storm report, Jul 17, 10:42 PM MDT, 1 hour 41 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BILLINGS, MT
1042 PM MDT WED JUL 17 2002

TIME(MDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0810 PM    ST. XAVIER                MT   60-70 MPH MPH WIND GUST
07/17/02   BIG HORN

0830 PM    CROW AGENCY               MT   65 MPH WIND GUST
07/17/02   BIG HORN

0842 PM    2 SW HARDIN               MT   FUNNEL CLOUD
07/17/02   BIG HORN                       PUBLIC REPORTED POSSIBLE
                                          FUNNEL CLOUD

TC

Local storm report, Jul 17, 10:43 PM MDT, 1 hour 40 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BILLINGS, MT
1043 PM MDT WED JUL 17 2002

TIME(MDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0810 PM    ST. XAVIER                MT   60-70 MPH MPH WIND GUST
07/17/02   BIG HORN

0830 PM    CROW AGENCY               MT   65 MPH WIND GUST
07/17/02   BIG HORN

0842 PM    2 SW HARDIN               MT   FUNNEL CLOUD
07/17/02   BIG HORN                       PUBLIC REPORTED POSSIBLE
                                          FUNNEL CLOUD

TC

The office that day

Everything else NWS Billings, MT issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 18, 12:27 AM MDT	Severe Thunderstorm Warning	BYZ	Sheridan	53 min

Nearby

Severe Thunderstorm Warnings in Wyoming, 2002 Every 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.