Alert archive / Montana / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 2, NWS Billings, MT

April 30, 2001Big Horn County, Montana

NWS Billings, MT issued this severe thunderstorm warning at Apr 30, 2001, 11:42 PM MDT for Big Horn County, Montana. It was in force for 48 min. 2 reports 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: Apr 30, 2001, 11:42 PM MDT (05:42 UTC)
Expired: May 1, 2001, 12:30 AM MDT
In force: 48 min
Issued by: NWS Billings, MT
Area: Whole counties

County Big Horn County, MT

What was reported inside it

Time	Report	Where	Remark
May 1, 12:05 AM MDT	Thunderstorm Wind 65 E	Crow Agency, MT	65 mph thunderstorm wind gust
May 1, 12:36 AM MDT	Thunderstorm Wind 61 M	Hardin, MT	61 mph thunderstorm wind gust at the Pryor Mountain RAWS site.

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, 5.7 hours before the alert went out and 272 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 2788 m above ground
0-6 km bulk shear: 46 kt
0-1 km storm-relative helicity: 79 m²/s²
0-3 km storm-relative helicity: 274 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.

000 
WUUS55 KBYZ 010545
SVRBIL

MTC003-010630-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE BILLINGS MT
1142 PM MDT MON APR 30 2001

THE NATIONAL WEATHER SERVICE IN BILLINGS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  BIG HORN COUNTY IN SOUTH CENTRAL MONTANA
  THIS INCLUDES THE CITY OF HARDIN

* UNTIL 1230 AM MDT

* AT 1142 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM WITH DAMAGING WINDS 8 MILES WEST OF            
  HARDIN...MOVING EAST AT 65 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
   CROW AGENCY BY 1150 PM MDT.
   LODGE GRASS BY 1155 PM MDT.
   BUSBY BY 1210 AM MDT.

* THIS STORM HAS HISTORY OF 70 MPH WINDS IN BILLINGS.

* THIS IS AN EXTENSION OF THE EARLIER WARNING FOR BIG HORN COUNTY.

$$

LAT...LON 4588 10787 4586 10802 4557 10803 4502 10807
          4503 10681 4563 10682 4567 10692 4585 10699
          4595 1074-3 4596 10770

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 Apr 30, 9:10 PM MDT, 2 hours 32 minutes earlier.

Area forecast discussion, Apr 30, 9:10 PM MDT, 2 hours 32 minutes before

SOUTH CENTRAL AND SOUTHEAST MONTANA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BILLINGS MT
910 PM MDT MON APR 30 2001

.TUE AND WED...

SHORTWAVE SEEN ON WATER VAPOR IMAGERY OVER NORTHERN IDAHO EARLY TONIGHT.
MOISTURE PROGRESSING EASTWARD AHEAD OF THE WAVE AND SURFACE COLD FRONT
HAS JUST GONE THROUGH BUTTE. AS THE FRONT WORKS ITS WAY TO OUR AREA
TONIGHT...SCATTERED SHOWERS WILL SPREAD EASTWARD. THE BIGGEST ISSUE
THROUGH TUESDAY WILL BE THE STRENGTH OF THE WINDS. GUSTY WINDS WILL
LIKELY ACCOMPANY FRONTAL PASSAGE...BUT A TEMPORARY LIMITING FACTOR ON
GUST POTENTIAL WILL BE DEVELOPING NIGHT-TIME LOW LEVEL INVERSIONS. AS
THE SHORTWAVE MOVES OVER NORTH DAKOTA TUESDAY...PARTS OF SOUTH-CENTRAL
AND SOUTHEASTERN MONTANA WILL BE UNDER WAVE SUBSIDENCE...COLD AIR
ADVECTION AND LINKAGE WITH STRONG WINDS ALOFT. EXPECTING STRONGEST WINDS
OVER THE SOUTHEAST TUESDAY AS CURRENT FORECAST INDICATES...BUT BELOW
HIGH WIND WARNING CRITERIA. AS LOW LEVEL INVERSIONS MIX OUT TUESDAY
MORNING...SFC WINDS WILL BEGIN TO LINK WITH STRONGER WINDS ALOFT. 00Z
ETA CONSISTENT WITH FORECASTING 35 KT WINDS AT 850MB...AND 40-50 KT
WINDS AT 700MB TUESDAY.

SO...THE GOING FORECAST IS O.K. BUT WINDS HAVE DIED OFF FROM BILLINGS
EASTWARD. FOR THIS...WILL UPDATE TO FRESHEN UP WORDING A BIT. POPS AND
MIN TEMPS LOOK GOOD TO GO. CANEPA

.THU...FRI...SAT...SUN...MON...
CUTOFF LOW ACROSS THE DESERT SOUTHWEST THURSDAY MODELS DEPICT TO SLOWLY
MEANDER AROUND THEN LIFT NORTHEAST INTO THE GREAT PLAINS SATURDAY AND
SUNDAY. POSITIVELY TILTED RIDGE THEN MOVES INTO THE NORTHERN ROCKIES BY
MONDAY. WILL SLOWLY WARM TEMPS THROUGH THE PERIOD WITH GENERALLY DRY
CONDITIONS EXCEPT DURING THE TIME THE UPPER LOW FILLS AND MOVES OUT OF
THE AREA. THORICHT

    TUE     WED     THU     FRI     SAT     SUN     MON
-----------------------------------------------------------
BIL 042/053 036/053 034/057 040/062 043/065 045/068 044/070
    42/W    03/W    32/B    22/B    33/W    32/B    22/B
LVM 042/053 034/053 032/056 038/062 041/065 044/068 042/068
    43/W    23/W    32/B    22/B    33/W    32/B    22/B
HDN 040/054 034/054 032/058 038/063 041/066 043/069 042/069
    42/W    03/W    32/B    22/B    33/W    32/B    22/B
MLS 045/056 038/056 035/058 040/065 043/067 045/071 044/072
    43/W    03/W    32/B    22/B    33/W    32/B    22/B
4BQ 044/056 038/056 034/057 038/064 041/065 044/069 042/070
    43/W    03/W    32/B    22/B    33/W    32/B    22/B
BHK 043/055 037/055 033/056 037/062 040/064 042/068 041/069
    43/W    03/W    32/B    22/B    33/W    32/B    22/B
SHR 038/053 030/053 032/055 036/059 038/065 040/067 039/068
    42/W    03/W    32/B    22/B    33/W    32/B    22/B

In the hours before

Local storm report, Apr 30, 9:56 PM MDT, 1 hour 46 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BILLINGS, MT
956 PM MDT MON APR 30 2001

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

1100 PM    BILLINGS AIRPORT          MT   69 MPH TSTM WIND GUST
04/30/01   YELLOWSTONE

1235 AM    COLSTRIP                  MT   70 MPH TSTM WIND GUST
05/01/01   ROSEBUD

1250 AM    BROADUS                   MT   60 MPH TSTM WIND GUST
05/01/01   POWDER RIVER

1158 PM    CROW AGENCY               MT   65 MPH TSTM WIND GUST
04/30/01   BIG HORN

0100 AM    SHERIDAN                  WY   76 MPH TSTM WIND GUST
05/01/01   SHERIDAN

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 30, 10:48 PM MDT	Severe Thunderstorm Warning	BYZ	Big Horn, Yellowstone	57 min
May 1, 12:18 AM MDT	Severe Thunderstorm Warning	BYZ	Powder River, Rosebud	42 min

Nearby

Severe Thunderstorm Warnings in Montana, 2001 Every 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.