Alert archive / Montana / Tornado Warnings in 1999

Tornado Warning 7, NWS Great Falls, MT

August 14, 1999Fergus County, Montana

NWS Great Falls, MT issued this tornado warning at Aug 14, 1999, 7:54 PM MDT for Fergus County, Montana. It was in force for 66 min. 1 report came from 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, with what was reported inside it.

The facts

Issued
Aug 14, 1999, 7:54 PM MDT (01:54 UTC)
Expired
Aug 14, 1999, 9:00 PM MDT
In force
66 min
Issued by
NWS Great Falls, MT
Area
Whole counties; the outline is the Mesonet’s reconstruction

County Fergus County, MT

The radar

The Billings radar (KBLX), 148 km from the middle of the area, began a volume at 01:54 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

TimeReportWhereRemark
Aug 14, 8:15 PM MDTTornado F0Lewistown, MT

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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Aug 14, 4:15 PM MDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Great_falls, MT (KTFX), launched 00:00Z, 1.9 hours before the alert went out and 116 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, Great_falls, MT at 00:00Z on 1999-08-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 13 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, Great_falls, MT at 00:00Z on 1999-08-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 60 square meters per square second.19395878Sfc1 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
13 J/kg
Mixed-layer CIN
-177 J/kg
Mixed-layer LCL
1802 m above ground
0-6 km bulk shear
61 kt
0-1 km storm-relative helicity
60 m²/s²
0-3 km storm-relative helicity
225 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 
TTAA00 KTFX 150158 RRA
TORGTF
MTC027-150300-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE GREAT FALLS MT
754 PM MDT SAT AUG 14 1999

THE NATIONAL WEATHER SERVICE IN GREAT FALLS IS CONTINUING THE.

* TORNADO WARNING FOR...
  CENTRAL FERGUS COUNTY IN MONTANA.
  THIS INCLUDES THE CITY OF LEWISTOWN.

* UNTIL 900 PM MDT.

* AT 748 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  THUNDERSTORM WITH A POSSIBLE TORNADO 2 MILES NORTHWEST OF
  LEWISTOWN...MOVING EAST AT 30 MPH.

THIS STORM HAS HAD A LONG HISTORY OF PRODUCING A TORNDAO AND VERY 
LARGE HAIL.

IF YOU ARE CAUGHT OUTSIDE...SEEK SHELTER IN A NEARBY REINFORCED
BUILDING. AS A LAST RESORT...SEEK SHELTER IN A CULVERT...DITCH OR LOW
SPOT AND COVER YOUR HEAD WITH YOUR HANDS.

THE SAFEST PLACE TO BE DURING A TORNADO IS IN A BASEMENT. GET UNDER A
WORKBENCH OR OTHER PIECE OF STURDY FURNITURE. IF NO BASEMENT IS
AVAILABLE...SEEK SHELTER ON THE LOWEST FLOOR OF THE BUILDING IN AN
INTERIOR HALLWAY OR ROOM SUCH AS A CLOSET. USE BLANKETS OR PILLOWS TO
COVER YOUR BODY AND ALWAYS STAY AWAY FROM WINDOWS.

IF IN MOBILE HOMES OR VEHICLES...EVACUATE THEM AND GET INSIDE A
SUBSTANTIAL SHELTER. IF NO SHELTER IS AVAILABLE...LIE FLAT IN THE
NEAREST DITCH OR OTHER LOW SPOT AND COVER YOUR HEAD WITH YOUR HANDS.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 1000 PM MDT
SATURDAY EVENING FOR MONTANA.

LAT...LON 4718 10948 4700 10946 4704 10862 4726 10865

$$

BRUSDA

What forecasters said that day

The local office's own words before this tornado warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Great Falls, MT wrote its last area forecast discussion before this tornado warning went out at Aug 14, 2:45 PM MDT, 5 hours 9 minutes earlier.

Area forecast discussion, Aug 14, 2:45 PM MDT, 5 hours 9 minutes before
SOUTHWEST AND NORTH CENTRAL MONTANA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
245 PM MDT SAT AUG 14 1999

12Z MDL DATA SLOW TO ARRIVE. NGM AND AVN FAIRLY SIMILAR WITH MOST
DETAILS OF UPR TROF MOVG E. SAT IMAGERY INDICATES UPR LOW OVR XTRM ERN
WA ATTM WITH A FAIRLY WELL DEFINED MSTR PLUME THRU N-CNTRL ID AND WRN
MT. SOME CNVTV ACTVTY ALRDY KICKING OFF OVR SW MT BUT TSTMS HAVE BEEN
WEAK. WL LEAVE HIGHEST POPS TGNT FOR SW AND NW PORTION OF CWA AND THEN
GO WITH HIGH POPS ACRS N-CNTRL MT SUN. AVN HAS WLY FLOW OVR CWA BY SUN
NGT WITH ANOTHER S/WV DROPPING INTO NW MT MON. COOLER AIR FOR SUN WITH A
SLGT WRMG MON. EMANUEL
GTF 5512 HLN 6423 HVR 5632

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 14, 6:17 PM MDTSevere Thunderstorm WarningTFXFergus43 min
Aug 14, 6:22 PM MDTSevere Thunderstorm WarningTFXFergus53 min
Aug 14, 6:37 PM MDTTornado WarningTFXFergus33 min
Aug 14, 6:55 PM MDTSevere Thunderstorm WarningTFXJudith Basin50 min
Aug 14, 7:12 PM MDTTornado WarningTFXJudith Basin33 min
Aug 14, 7:17 PM MDTSevere Thunderstorm WarningTFXFergus28 min
Aug 14, 7:35 PM MDTTornado WarningTFXFergus, Judith Basin25 min
Aug 14, 10:22 PM MDTSevere Thunderstorm WarningTFXFergus38 min

Nearby

Tornado Warnings in Montana, 1999Every tornado warning in 1999Tornadoes in 1999

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.