Alert archive / Montana / Severe Thunderstorm Warnings in 2013

Severe Thunderstorm Warning 64, NWS Great Falls, MT

July 17, 2013Gallatin County, Madison County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at Jul 17, 2013, 5:00 PM MDT for Gallatin County, Madison County, Montana. It was in force for 45 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 17, 2013, 5:00 PM MDT (23:00 UTC)
Expired
Jul 17, 2013, 5:45 PM MDT
In force
45 min
Issued by
NWS Great Falls, MT
Area
Storm-based polygon

Counties Gallatin County, MT, Madison County, MT

The radar

The Great Falls radar (KTFX), 227 km from the middle of the area, began a volume at 23:03 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.

The watch it was issued in

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

IssuedProductOfficeLasted
Jul 17, 2:48 PM MDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Great_falls, MT (KTFX), launched 12:00Z, 11.0 hours before the alert went out and 238 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 2013-07-17Temperature 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 2013-07-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -6 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1289 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
-6 m²/s²
0-3 km storm-relative helicity
-14 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

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 17, 3:01 PM MDT, 1 hour 59 minutes earlier.

Area forecast discussion, Jul 17, 3:01 PM MDT, 1 hour 59 minutes before
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Hazardous weather outlook, Jul 17, 4:16 AM MDT, 12 hours 44 minutes before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREAT FALLS MT
416 AM MDT WED JUL 17 2013

MTZ008>015-044>055-181030-
BEAVERHEAD-NORTHERN ROCKY MOUNTAIN FRONT-EASTERN GLACIER-HILL-
CASCADE-CHOUTEAU-CENTRAL AND SOUTHERN LEWIS AND CLARK-MADISON-
TOOLE-LIBERTY-EASTERN PONDERA-BLAINE-
SOUTHERN ROCKY MOUNTAIN FRONT-EASTERN TETON-JUDITH BASIN-FERGUS-
JEFFERSON-BROADWATER-MEAGHER-GALLATIN-
416 AM MDT WED JUL 17 2013

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL
MONTANA...NORTH CENTRAL MONTANA AND SOUTHWEST MONTANA.

.DAY ONE...TODAY AND TONIGHT

STRONG TO SEVERE THUNDERSTORMS WITH STRONG TO DAMAGING WINDS...HAIL
AND LOCALLY HEAVY RAIN ARE EXPECTED THIS AFTERNOON AND EVENING.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

THE PROBABILITY IS LOW FOR WIDESPREAD HAZARDOUS WEATHER.

.SPOTTER INFORMATION STATEMENT...

ANY REPORTS OF STRONG WINDS...HAIL AND/OR STORM DAMAGE WOULD BE
GREATLY APPRECIATED AND CAN BE RELAYED TO THE NWS GREAT FALLS OR
LOCAL LAW ENFORCEMENT.

In the hours before

Local storm report, Jul 17, 4:45 PM MDT, 15 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
445 PM MDT WED JUL 17 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0444 PM     HAIL             2 N HELENA              46.63N 112.02W
07/17/2013  E0.50 INCH       LEWIS AND CLARK    MT   TRAINED SPOTTER

            HALF INCH HAIL ON THE NORTH SIDE OF HELENA.

&&

BRUSDA
Special weather statement, Jul 17, 4:45 PM MDT, 15 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREAT FALLS MT
445 PM MDT WED JUL 17 2013

MTZ008-172330-
BEAVERHEAD MT-
445 PM MDT WED JUL 17 2013

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN BEAVERHEAD COUNTY
UNTIL 530 PM MDT...

AT 442 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A
STRONG THUNDERSTORM 5 MILES SOUTH OF LIMA...OR 35 MILES WEST OF
IDMON...MOVING EAST AT 30 MPH.

HAIL UP TO ONE-HALF INCH IN DIAMETER AND WIND GUSTS UP TO 50 MPH ARE
EXPECTED WITH THIS STORM...ALONG WITH HEAVY RAIN AND FREQUENT
DANGEROUS LIGHTNING.

* LOCATIONS IMPACTED INCLUDE...
   MONIDA...

THIS STORM MAY INTENSIFY...SO BE CERTAIN TO MONITOR LOCAL RADIO AND
TV STATIONS...AS WELL AS LOCAL CABLE TV OUTLETS...FOR ADDITIONAL
INFORMATION AND POSSIBLE WARNINGS FROM THE NATIONAL WEATHER SERVICE.

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

LAT...LON 4447 11246 4446 11250 4448 11260 4448 11268
      4449 11270 4479 11261 4474 11184 4455 11187
      4452 11212 4456 11229 4453 11234 4446 11236
      4444 11243
TIME...MOT...LOC 2245Z 279DEG 28KT 4456 11253

NL
Local storm report, Jul 17, 4:46 PM MDT, 14 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
446 PM MDT WED JUL 17 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0438 PM     HAIL             3 W HELENA              46.60N 112.08W
07/17/2013  E0.75 INCH       LEWIS AND CLARK    MT   TRAINED SPOTTER

            PENNY SIZE HAIL ON THE WEST SIDE OF HELENA.

&&

BRUSDA
Local storm report, Jul 17, 4:48 PM MDT, 12 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
448 PM MDT WED JUL 17 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0446 PM     HAIL             ENNIS                   45.35N 111.73W
07/17/2013  E0.25 INCH       MADISON            MT   TRAINED SPOTTER

            PEA SIZE HAIL

&&

BRUSDA
Special weather statement, Jul 17, 4:51 PM MDT, 9 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREAT FALLS MT
451 PM MDT WED JUL 17 2013

MTZ015-172330-
MADISON MT-
451 PM MDT WED JUL 17 2013

...SIGNIFICANT WEATHER ADVISORY FOR CENTRAL MADISON COUNTY UNTIL 530
PM MDT...

AT 448 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A
STRONG THUNDERSTORM 8 MILES SOUTHWEST OF SHERIDAN...MOVING NORTHEAST
AT 25 MPH.

HAIL UP TO ONE-HALF INCH IN DIAMETER AND WIND GUSTS UP TO 50 MPH ARE
EXPECTED WITH THIS STORM...ALONG WITH HEAVY RAIN AND FREQUENT
DANGEROUS LIGHTNING.

* LOCATIONS IMPACTED INCLUDE...
   LAURIN AND  ALDER...
   SHERIDAN AND  LAURIN...

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

LAT...LON 4573 11192 4541 11170 4526 11231 4541 11245
TIME...MOT...LOC 2251Z 239DEG 23KT 4538 11227

NL
Special weather statement, Jul 17, 4:52 PM MDT, 8 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREAT FALLS MT
452 PM MDT WED JUL 17 2013

MTZ008-015-172330-
BEAVERHEAD MT-MADISON MT-
452 PM MDT WED JUL 17 2013

...SIGNIFICANT WEATHER ADVISORY FOR NORTHWESTERN MADISON AND NORTHERN
BEAVERHEAD COUNTIES UNTIL 530 PM MDT...

AT 454 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A
STRONG THUNDERSTORM 13 MILES WEST OF TWIN BRIDGES...OR 21 MILES
NORTHWEST OF SHERIDAN...MOVING NORTHEAST AT 20 MPH.

HAIL UP TO ONE-HALF INCH IN DIAMETER AND WIND GUSTS UP TO 50 MPH ARE
EXPECTED WITH THIS STORM...ALONG WITH HEAVY RAIN AND FREQUENT
DANGEROUS LIGHTNING.

* LOCATIONS IMPACTED INCLUDE...
  RURAL NORTHWESTERN MADISON COUNTY...
  RURAL NORTHERN BEAVERHEAD COUNTY...

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

LAT...LON 4566 11270 4564 11269 4569 11257 4577 11250
      4575 11247 4575 11217 4569 11207 4547 11255
      4556 11277
TIME...MOT...LOC 2252Z 211DEG 18KT 4559 11259

NL

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 17, 2:53 PM MDTSpecial Weather StatementTFXMadison52 min
Jul 17, 3:19 PM MDTSpecial Weather StatementTFX41 min
Jul 17, 3:59 PM MDTSpecial Weather StatementTFXBeaverhead46 min
Jul 17, 4:02 PM MDTSpecial Weather StatementTFXBeaverhead43 min
Jul 17, 4:07 PM MDTSpecial Weather StatementTFXMadison38 min
Jul 17, 4:23 PM MDTSevere Thunderstorm WarningTFXLewis and Clark37 min
Jul 17, 4:30 PM MDTSpecial Weather StatementTFXLewis and Clark45 min
Jul 17, 4:31 PM MDTSevere Thunderstorm WarningTFXBeaverhead, Madison44 min
Jul 17, 4:44 PM MDTSpecial Weather StatementTFXBroadwater46 min
Jul 17, 4:51 PM MDTSpecial Weather StatementTFXMadison39 min
Jul 17, 4:52 PM MDTSpecial Weather StatementTFXSilver Bow38 min
Jul 17, 5:20 PM MDTSpecial Weather StatementTFXLewis and Clark40 min
Jul 17, 5:43 PM MDTAreal Flood AdvisoryTFXJefferson, Lewis and Clark6 hr
Jul 17, 5:45 PM MDTSpecial Weather StatementTFXPondera45 min
Jul 17, 5:46 PM MDTSpecial Weather StatementTFXGallatin44 min

Nearby

Severe Thunderstorm Warnings in Montana, 2013Every severe thunderstorm warning in 2013

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; radar from the NEXRAD Level II archive.