Alert archive / Montana / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 49, NWS Great Falls, MT

July 16, 2001Cascade County, Meagher County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at Jul 16, 2001, 3:55 PM MDT for Cascade County, Meagher County, Montana. It was in force for 35 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
Jul 16, 2001, 3:55 PM MDT (21:55 UTC)
Expired
Jul 16, 2001, 4:30 PM MDT
In force
35 min
Issued by
NWS Great Falls, MT
Area
Whole counties

Counties Cascade County, MT, Meagher County, MT

The watch it was issued in

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

IssuedProductOfficeLasted
Jul 16, 1:45 PM MDTSevere Thunderstorm WatchSPC5 hr

The nearest sounding before it

Great_falls, MT (KTFX), launched 12:00Z, 9.9 hours before the alert went out and 69 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 12:00Z on 2001-07-16Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 12:00Z on 2001-07-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 15 square meters per square second.1939Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1797 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
15 m²/s²
0-3 km storm-relative helicity
56 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

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 Great Falls, MT wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 16, 3:00 PM MDT, 55 minutes earlier.

Area forecast discussion, Jul 16, 3:00 PM MDT, 55 minutes before
SOUTHWEST AND NORTH CENTRAL MONTANA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
300 PM MDT MON JUL 16 2001

THE PATTERN IS QUITE SIMILAR TO THE PAST FEW DAYS. LOW PRESSURE
CENTERED OVER WA AND BRITISH COLUMBIA...AND A TROF EXTENDING DOWN
ACROSS THE PAC NW.  MOST OF THE INDICES LOOK A LITTLE MORE
THREATENING THAN YESTERDAY...AND CERTAINLY THE WIND SHEAR PATTERN IS
QUITE A BIT BETTER FOR SEVERE WEATHER THAN YESTERDAY. MOST
IMPORTANTLY...A SHORT WAVE PUSHES THRU LATER THIS AFTERNOON AND
EVENING...WITH AN ASSOCIATED SURFACE FRONT. WATCH BOX 559 HAS ALREADY
BEEN ISSUED FOR THE ERN CWA OF MSO AND MOST OF OUR CWA. TUESDAY
ONWARD NOT TOO MUCH CHANGE GOING ON.  SURFACE TEMPS SHOULD TREND A
LITTLE COOLER AS CAA CONTINUES...BUT AT THE SAME TIME THE HEIGHTS
ALOFT WILL BE DROPPING.  THUS AIRMASS REMAINS RELATIVELY UNSETTLED.
ZELZER

EXTENDED...SOME DIFFERENCE AMONG THE MODELS...BUT DO KEEP
UPPER TROUGH OVER PACIFIC NORTHWEST FOR CONTINUED MOIST AND
UNSTABLE SOUTHWEST FLOW FOR DAYS 3 AND 4. UPPER TROUGH THEN
SLITS BY DAY 5 WITH THE NORTHERN BRANCH MOVING THROUGH AREA.
WEAK UPPER RIDGE BUILDS BY DAY 6 AND 7 FOR DRY AND WARMER
WEATHER. TEMPERATURES WILL BE A LITTLE BELOW NORMAL WITH AT
OR A LITTLE ABOVE NORMAL PRECIPITATION.

CCF NUMBERS
GTF EE 050 078 048 074 048 135122
CTB EE 048 072 046 070 045 135122
HLN EE 050 075 048 075 048 135222
BZN EE 047 075 047 073 045 136323
WEY PEE 052 074 040 072 038 136322
DLN EE 046 072 045 072 045 135223
HVR EE 057 080 054 080 052 136122
LWT EE 050 072 050 070 048 136222

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 16, 2:53 PM MDTSevere Thunderstorm WarningTFXJefferson, Lewis and Clark37 min
Jul 16, 2:58 PM MDTSevere Thunderstorm WarningTFXLewis and Clark32 min
Jul 16, 3:53 PM MDTSevere Thunderstorm WarningTFXCascade37 min
Jul 16, 4:28 PM MDTSevere Thunderstorm WarningTFXCascade, Judith Basin, Meagher47 min
Jul 16, 4:34 PM MDTSevere Thunderstorm WarningTFXGlacier, Pondera, Toole41 min
Jul 16, 5:18 PM MDTSevere Thunderstorm WarningTFXToole42 min

Nearby

Severe Thunderstorm Warnings in Montana, 2001Every 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; the sounding from the Mesonet's radiosonde archive.