Alert archive / Montana / Severe Thunderstorm Warnings in 2013

Severe Thunderstorm Warning 10, NWS Great Falls, MT

June 13, 2013Cascade County, Lewis and Clark County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at Jun 13, 2013, 1:12 AM MDT for Cascade County, Lewis and Clark County, Montana. It was in force for 48 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: Jun 13, 2013, 1:12 AM MDT (07:12 UTC)
Expired: Jun 13, 2013, 2:00 AM MDT
In force: 48 min
Issued by: NWS Great Falls, MT
Area: Storm-based polygon

Counties Cascade County, MT, Lewis and Clark County, MT

The radar

The Great Falls radar (KTFX), 45 km from the middle of the area, began a volume at 07:12 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 nearest sounding before it

Great_falls, MT (KTFX), launched 00:00Z, 7.2 hours before the alert went out and 99 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: 457 J/kg
Mixed-layer CIN: -83 J/kg
Mixed-layer LCL: 1292 m above ground
0-6 km bulk shear: 60 kt
0-1 km storm-relative helicity: 151 m²/s²
0-3 km storm-relative helicity: 262 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 2.4

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 Jun 12, 10:45 PM MDT, 2 hours 27 minutes earlier.

Area forecast discussion, Jun 12, 10:45 PM MDT, 2 hours 27 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
1045 PM MDT Wed Jun 12 2013

UPDATED AVIATION SECTION

...UPDATE TO HYDROLOGY SECTION...

.UPDATE...
Showers and a few thunderstorms will continue to move northeast
through central and north central Montana the rest of the evening.
The threat for severe weather appears to be over so the severe
thunderstorm watch has been cancelled. A weather disturbance aloft
will track north near the continental divide after midnight so
have increased the chances of precipitation over the far northwest
zones for that period. Otherwise latest guidance continues to
forecast scattered showers and possibly a few thunderstorms over
the rest of the forecast area after midnight so will continue with
the chance category chances of precipitation. Raised some forecast
lows a few degrees for tonight. Blank

&&

.DISCUSSION...
/ISSUED 600 PM MDT Wed Jun 12 2013/

Tonight through Friday...An unstable airmass with good rotational
shear will fuel strong to severe thunderstorms this afternoon and
evening. Locally heavy rainfall could cause flash flooding in some
locations as well. The risk of severe weather should decrease by
midnight with the main band of precipitation shifting from my
central zones to the northwest overnight. By Thursday morning a
surface cold front will push eastward through my CWA with the best
chance of precipitation shifting along with the frontal boundary.
While some thunderstorms remain possible during this time period
it is anticipated that the best chance of severe weather will
shift into eastern Montana so central and southwest portions of
the state should have a respite from the stronger storms. An upper
level trough associated with the surface cold front moves eastward
over the state Thursday night and Friday. Cool and unsettled
weather conditions will prevail through Friday with scattered
showers and some thunderstorms. With the cooler and less unstable
airmass over the area, once again, strong thunderstorms should not
be a concern. mpj

Friday night through Wednesday...High confidence in the long term
forecast continues. Models remain in excellent pattern agreement
throughout the long term forecast. A broad low pressure trough over
the Pacific Northwest will keep unstable southwest flow over the
region into Friday night. Periods of showers and scattered
thunderstorms look likely across Central Montana during this period.
Precipitation details vary but most of Central Montana looks to have
a fair shot at getting some rain by Friday. The main trough will
lift to the northeast into Southern Canada early Saturday leaving a
nice weekend in its wake. High pressure will build back in from the
southeast Saturday before breaking down ahead of a large low
pressure system approaching the Pacific coast Monday. Expect Monday
and Tuesday to return to somewhat unstable conditions with periods
of showers and thunderstorms possible. The trough looks to move over
the Rockies Wednesday bringing better chances for precipitation to
much of Central Montana. Temperatures warm back up Saturday through
Monday before falling Tuesday in response to the incoming system.
Winds look to remain mostly light with some afternoon breeziness.

&&

.AVIATION...
Updated 0445Z.
Showers and Thunderstorms will diminish over the next few hours from
KGTF to KHVR. Additional showers and possibly a thunderstorms will
redevelop towards morning around KCTB as a cold front and upper
level disturbance pass through the area. Low CIGS and light rain or
drizzle will accompany the front as it pushes through the area
during the morning. This will bring widespread MVFR conditions to
north central Montana. Lower CIGS will also push into the southwest
by late morning, models indicate KHLN and KBZN will remain VFR but
MVFR conditions can not be ruled out. CIGS will improve during the
afternoon with VFR conditions expected by Thursday evening. Langlieb
&&

.HYDROLOGY...
Point flood warnings remain in effect for the Big Sandy Creek near
Havre and Clear Creek near Chinook as water levels, though
generally decreasing, remain above flood stage. Thunderstorm
activity has been generally diminishing this evening. Have
cancelled all flash flood watches as the threat for heavy rain has
diminished. Blank

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  51  63  44  64 /  60  70  30  30
CTB  46  61  42  63 /  60  70  20  30
HLN  50  65  45  64 /  60  60  40  40
BZN  49  70  42  62 /  40  50  50  60
WEY  39  68  35  57 /  50  30  30  40
DLN  48  66  40  61 /  50  60  50  60
HVR  57  70  47  69 /  70  70  40  20
LWT  52  68  44  61 /  60  60  60  40

&&

.TFX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

SHORT TERM...BLANK
LONG TERM...LANGLIEB
AVIATION...LANGLIEB

weather.gov/greatfalls

Hazardous weather outlook, Jun 12, 9:48 PM MDT, 3 hours 24 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREAT FALLS MT
948 PM MDT WED JUN 12 2013

MTZ011-047-140400-
HILL-BLAINE-
948 PM MDT WED JUN 12 2013

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

.DAY ONE...TONIGHT

A FLASH FLOOD WATCH IS IN EFFECT UNTIL MIDNIGHT MDT.

FLOOD WARNINGS CONTINUE OUT FOR BIG SANDY CREEK AND CLEAR CREEK.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

FLOOD WARNINGS WILL CONTINUE FOR BIG SANDY CREEK AND CLEAR CREEK.

A SECOND ROUND OF THUNDERSTORMS IS EXPECTED ON THURSDAY. THE
THREAT OF SEVERE WEATHER IS LOW...BUT SOME STORMS MAY PRODUCE
SMALL HAIL AND MODERATE RAINFALL BRINGING FURTHER STREAM RISES
AND RURAL FLOODING.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

MTZ013-050-051-140400-
CHOUTEAU-JUDITH BASIN-FERGUS-
948 PM MDT WED JUN 12 2013

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

.DAY ONE...TONIGHT

A FLASH FLOOD WATCH CONTINUES UNTIL MIDNIGHT MDT.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

A SECOND ROUND OF THUNDERSTORMS IS EXPECTED ON THURSDAY. THE
THREAT OF SEVERE WEATHER IS LOW...BUT SOME STORMS MAY PRODUCE
SMALL HAIL AND MODERATE RAINFALL BRINGING FURTHER STREAM RISES
AND RURAL FLOODING.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

MTZ008>010-012-014-015-044>046-048-049-052>055-140400-
BEAVERHEAD-NORTHERN ROCKY MOUNTAIN FRONT-EASTERN GLACIER-CASCADE-
CENTRAL AND SOUTHERN LEWIS AND CLARK-MADISON-TOOLE-LIBERTY-
EASTERN PONDERA-SOUTHERN ROCKY MOUNTAIN FRONT-EASTERN TETON-
JEFFERSON-BROADWATER-MEAGHER-GALLATIN-
948 PM MDT WED JUN 12 2013

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

.DAY ONE...TONIGHT

THERE IS A LOW PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER THE
REST OF TONIGHT.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

A SECOND ROUND OF THUNDERSTORMS IS EXPECTED ON THURSDAY. THE THREAT
OF SEVERE WEATHER IS LOW BUT SOME STORMS MAY PRODUCE SMALL HAIL
AND MODERATE RAINFALL.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

In the hours before

Local storm report, Jun 12, 7:37 PM MDT, 5 hours 35 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
737 PM MDT WED JUN 12 2013

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

0545 PM     HAIL             8 NE AUGUSTA            47.57N 112.25W
06/12/2013  E0.70 INCH       TETON              MT   TRAINED SPOTTER

            DIME SIZED HAIL AND BRIEF HEAVY RAIN.

&&

NJL

Special weather statement, Jun 12, 8:04 PM MDT, 5 hours 8 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREAT FALLS MT
804 PM MDT WED JUN 12 2013

MTZ050-051-130245-
FERGUS MT-JUDITH BASIN MT-
804 PM MDT WED JUN 12 2013

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN JUDITH BASIN AND
SOUTHWESTERN FERGUS COUNTIES UNTIL 845 PM MDT...

AT 800 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A
STRONG THUNDERSTORM 13 MILES SOUTHWEST OF HOBSON...OR 24 MILES
SOUTHEAST OF STANFORD...MOVING NORTHEAST AT 25 MPH.

HAIL UP TO THE SIZE OF PENNIES AND WIND GUSTS UP TO 50 MPH ARE
EXPECTED WITH THIS STORM. VERY HEAVY RAIN WILL ALSO ACCOMPANY THIS
STORM AND MAY CAUSE SMALL STREAMS AND CREEKS TO RISE RAPIDLY. PLEASE
DO NOT ATTEMPT TO DRIVE ACROSS ROADWAYS COVERED BY WATER.

* LOCATIONS IMPACTED INCLUDE...
   BUFFALO AND GARNEILL...
   HOBSON...
   MOORE...

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 NORTH CENTRAL MONTANA.

LAT...LON 4678 10948 4672 10991 4674 10997 4674 11001
      4683 11018 4713 10976
TIME...MOT...LOC 0203Z 239DEG 22KT 4684 10998

NL

Special weather statement, Jun 12, 8:15 PM MDT, 4 hours 57 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREAT FALLS MT
815 PM MDT WED JUN 12 2013

MTZ044-045-130300-
LIBERTY MT-TOOLE MT-
815 PM MDT WED JUN 12 2013

...SIGNIFICANT WEATHER ADVISORY FOR EASTERN TOOLE AND CENTRAL LIBERTY
COUNTIES UNTIL 900 PM MDT...

AT 810 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A
STRONG THUNDERSTORM 6 MILES SOUTHWEST OF LOTHAIR...OR 19 MILES WEST
OF CHESTER...MOVING NORTHEAST AT 25 MPH.

HAIL UP TO ONE-HALF INCH IN DIAMETER AND WIND GUSTS UP TO 40 MPH ARE
EXPECTED WITH THIS STORM. VERY HEAVY RAIN WILL ALSO ACCOMPANY THIS
STORM AND MAY CAUSE SMALL STREAMS AND CREEKS TO RISE RAPIDLY. PLEASE
DO NOT ATTEMPT TO DRIVE ACROSS ROADWAYS COVERED BY WATER.

* LOCATIONS IMPACTED INCLUDE...
   GALATA...
   LOTHAIR...

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 NORTH CENTRAL MONTANA.

LAT...LON 4874 11138 4859 11090 4832 11128 4841 11151
TIME...MOT...LOC 0215Z 211DEG 21KT 4844 11132

NL

Local storm report, Jun 12, 8:23 PM MDT, 4 hours 49 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
823 PM MDT WED JUN 12 2013

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

0822 PM     HAIL             1 W HELENA              46.60N 112.04W
06/12/2013  M0.50 INCH       LEWIS AND CLARK    MT   TRAINED SPOTTER

            DIME-SIZED HAIL NEAR CARROL COLLEGE.

&&

MLV

Local storm report, Jun 12, 9:00 PM MDT, 4 hours 12 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
900 PM MDT WED JUN 12 2013

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

0858 PM     HEAVY RAIN       4 S BRADY               47.98N 111.84W
06/12/2013  M0.92 INCH       TETON              MT   TRAINED SPOTTER

            0.92 INCHES OF RAINFALL BETWEEN AROUND 5 AND 6 PM.

&&

NJL

Local storm report, Jun 12, 9:01 PM MDT, 4 hours 11 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
901 PM MDT WED JUN 12 2013

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

0600 PM     HEAVY RAIN       4 S BRADY               47.98N 111.84W
06/12/2013  M0.92 INCH       TETON              MT   TRAINED SPOTTER

            0.92 INCHES OF RAINFALL BETWEEN 5 AND 6 PM.

&&

NJL

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 12, 6:35 PM MDT	Special Weather Statement	TFX	Teton	40 min
Jun 12, 6:36 PM MDT	Special Weather Statement	TFX	Liberty	24 min
Jun 12, 6:41 PM MDT	Special Weather Statement	TFX	Judith Basin	49 min
Jun 12, 7:05 PM MDT	Special Weather Statement	TFX	Liberty	25 min
Jun 12, 7:26 PM MDT	Special Weather Statement	TFX	Wheatland	49 min
Jun 12, 7:34 PM MDT	Special Weather Statement	TFX	Liberty	41 min
Jun 12, 8:04 PM MDT	Special Weather Statement	TFX	Judith Basin	41 min
Jun 12, 8:15 PM MDT	Special Weather Statement	TFX	Liberty	45 min
Jun 13, 12:00 AM MDT	Severe Thunderstorm Warning	TFX	Lewis and Clark	45 min
Jun 13, 12:40 AM MDT	Severe Thunderstorm Warning	TFX	Cascade, Lewis and Clark	35 min
Jun 13, 1:55 AM MDT	Severe Thunderstorm Warning	TFX	Cascade	50 min
Jun 13, 5:30 PM MDT	Special Weather Statement	TFX	Wheatland	15 min

Nearby

Severe Thunderstorm Warnings in Montana, 2013 Every 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.