Severe Thunderstorm Warning 113, NWS Great Falls, MT

756 
WWUS55 KTFX 110038
SVSTFX

Severe Weather Statement
National Weather Service Great Falls MT
638 PM MDT Sat Aug 10 2019

MTC059-110045-
/O.CON.KTFX.SV.W.0113.000000T0000Z-190811T0045Z/
Meagher MT-
638 PM MDT Sat Aug 10 2019

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 645 PM MDT
FOR SOUTHEASTERN MEAGHER COUNTY...

At 638 PM MDT, a severe thunderstorm was located 13 miles southeast
of White Sulphur Springs, moving northeast at 20 mph.

HAZARD...Ping pong ball size hail and 60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...People and animals outdoors will be injured. Expect hail 
         damage to roofs, siding, windows, and vehicles. Expect wind 
         damage to roofs, siding, and trees.

Locations impacted include...
Checkerboard and Lennep. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Prepare immediately for large hail and deadly cloud to ground
lightning. Seek shelter inside a well-built structure. Stay away from
windows.

To report severe weather contact your nearest law enforcement agency.
They will send your report to the National Weather Service office in
Great Falls.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4630 11077 4643 11087 4661 11058 4638 11034
      4637 11037
TIME...MOT...LOC 0038Z 238DEG 19KT 4640 11072 

HAIL...1.50IN
WIND...60MPH
 
$$

Kredensor

Area Forecast Discussion
National Weather Service Great Falls MT
604 PM MDT Sat Aug 10 2019

...Aviation Section Update...

.SYNOPSIS...
An upper level trof will approaches and moves through the region
this weekend. As a result, expect showers and thunderstorms to
move through the area this afternoon and evening and again on
Sunday. Some storms could be severe, with gusty winds, hail.
Additionally, the rainfall could be heavy at times, causing
isolated areas of flash flooding. The work week will begin with
drier condtions and breezy westerly winds for most areas.

&&

.DISCUSSION...

Remainder of this afternoon through Sunday...Showers and
thunderstorms are just beginning to develop this afternoon over
the southwest. This activity is forecast to increase as
conditions are favorable for the potential for some severe
thunderstorms, especially over southwest and central Montana,
although the far southern areas of Beaverhead, Madison and
Gallatin Counties may be a bit drier than areas further north. MU
cape values are roughly falling in the 1000 to 2000 J/kg range,
while mid level lapse rates range from 7 to 8 degrees C. Moisture
remains plentiful as well, with .75 to 1 inch PWATS across much
of southwestern Montana and areas to the north (highest values
over the north-central). These factors along with good effective
shear has lead to the issue of a severe thunderstorm watch for
portions of the area through 9 pm tonight, some of the stronger
storms may produce wind gusts in excess of 60 mph, hail up to lime
size, along with heavy rains. One limiting factor is a stubborn
deck of low stratus over the central and north-central portions of
the region. This may lower the severe weather threat for portions
of the north but heavy rain will still be possible. A flash flood
watch remains in effect for areas along the Rocky Mountain Front
and then for Lewis and Clark and Cascade Counties, including
Helena and Great Falls (please see our hydrology section). Shower
and thunder storm activity should diminish by midnight but
showers and a few storms will be possible during the overnight
hours. Expect similar conditions on Sunday, as the main upper
level trof moves through the region. However, the focus of severe
weather is expected to shift a bit to the north and east.
Afternoon temperatures are likely to be a few degrees below normal
for most areas today and Sunday due to precipitation and cloud
cover.

Monday through Friday...With a light westerly flow over the
region, expect a slow warming trend, with only a very small chance
for a passing storm from Monday through Wednesday. On Thursday,
the next upper level trof approaches the region, allowing for the
potential for another round of severe storms to move through the
region. Showers then linger into Friday and Saturday, along with
below normal temperatures. Brusda

&&

.AVIATION...
Updated 604 PM MDT Sat Aug 10 2019 (11/00Z TAFs)

During this TAF period, expect MVFR conditions in association with
thunderstorm, rain and mist. Ceilings as low as OVC015 with
visibility to 4SM are forecast, along with all hazards assumed in
and near thunderstorm activity. Some storms in our CWA are producing
severe weather. Expect mountain and valley obscurations.
- Fogleman

&&

.FIRE WEATHER...
Periods of showers and thunderstorms will move through the region
from now through Sunday night. Most of the storms will be wet, but a
few storms could contain little rainfall or lightning could strike
away from the parent storm, resulting in new fire starts. Slightly
below normal temperatures are expected from today through early next
week, before a return to near normal temperatures is expected for
Tuesday and Wednesday.

Another round of storms is expected to move through the region
from late Thursday into Friday. Brusda/RCG

&&

.HYDROLOGY...
A flash flood watch remains in effect for areas along the Rocky
Mountain Front and portions of North Central MT from this
afternoon through late this evening. Some forecast models
continue to suggest that some areas may receive nearly 1 inch of
rainfall in less than 2 hours with the stronger storms this
afternoon and evening. This amount of rainfall could lead to
flooding problems in urban areas that have poor drainage, as well
as steep terrain and burn scar areas from this year or previous
years in areas that regrowth has not occurred. Brusda/RCG

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  53  75  52  74 /  90  80  70  10
CTB  50  71  50  71 /  70  80  70  30
HLN  52  76  49  76 /  90  90  70   0
BZN  48  78  45  77 /  40  70  50   0
WEY  43  71  35  71 /  10  30  20   0
DLN  47  72  42  74 /  40  70  50   0
HVR  51  76  52  73 /  50  80  90  50
LWT  50  74  49  71 /  80  80  80  10

&&

.TFX WATCHES/WARNINGS/ADVISORIES...
Flash Flood Watch until midnight MDT tonight Cascade...Central
and Southern Lewis and Clark...Northern Rocky Mountain Front...
Southern Rocky Mountain Front.

Severe thunderstorm watch is in effect until 9 pm MDT for the
following counties in central Montana - Fergus, Judith Basin,
Meagher, and Lewis and Clark...In southwest Montana - Beaverhead,
Broadwater, Gallatin, Jefferson, and Madison

&&

http://www.weather.gov/greatfalls

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
543 PM MDT SAT AUG 10 2019

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

0535 PM     HAIL             5 W CLANCY              46.47N 112.09W
08/10/2019  E0.25 INCH       JEFFERSON          MT   TRAINED SPOTTER

            PEA SIZED HAIL AND HEAVY RAIN WITH NO WIND.

&&

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
549 PM MDT SAT AUG 10 2019

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

0530 PM     HAIL             14 SSW BASIN            46.10N 112.41W
08/10/2019  E1.00 INCH       JEFFERSON          MT   TRAINED SPOTTER

            QUARTER SIZED HAIL REPORTED FOR A SHORT
            PERIOD BUT MOSTLY DIME SIZED AFTERWARD.

&&

Special Weather Statement
National Weather Service Great Falls MT
555 PM MDT Sat Aug 10 2019

MTZ053-110045-
Broadwater MT-
555 PM MDT Sat Aug 10 2019

...SIGNIFICANT WEATHER ADVISORY FOR NORTHWESTERN BROADWATER COUNTY
UNTIL 645 PM MDT...

At 554 PM MDT, Doppler radar was tracking a strong thunderstorm 8
miles west of Townsend, moving northeast at 25 mph.

Nickel size hail and winds in excess of 40 mph will be possible with
this storm.

Locations impacted include...
Townsend, Canyon Ferry Lake, Silos, Winston and Goose Bay.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with this storm, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

If on or near Canyon Ferry Lake, get out of the water and move
indoors or inside a vehicle. Remember, lightning can strike out to
10 miles from the parent thunderstorm. If you can hear thunder, you
are close enough to be struck by lightning. Move to safe shelter
now! Do not be caught on the water in a thunderstorm.

&&

A Severe Thunderstorm Watch remains in effect until 900 PM MDT for
central and southwestern Montana.

LAT...LON 4665 11156 4649 11125 4648 11125 4619 11166
      4627 11179 4639 11179
TIME...MOT...LOC 2354Z 218DEG 21KT 4631 11170

Kredensor

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
556 PM MDT SAT AUG 10 2019

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

0550 PM     HAIL             3 NNE CLANCY            46.50N 111.96W
08/10/2019  E0.50 INCH       JEFFERSON          MT   TRAINED SPOTTER

            HALF INCH HAIL AND HEAVY RAIN.

&&

Special Weather Statement
National Weather Service Great Falls MT
608 PM MDT Sat Aug 10 2019

MTZ054-110045-
Meagher-
608 PM MDT Sat Aug 10 2019

...A STRONG THUNDERSTORM WILL AFFECT SOUTHERN MEAGHER COUNTY...

At 608 PM MDT, a strong thunderstorm was located 14 miles south of
White Sulphur Springs, moving northeast at 20 mph.

Winds in excess of 40 mph and penny size hail are possible with this
storm.

Locations impacted include...
White Sulphur Springs and Ringling.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

To report severe weather, contact your nearest law enforcement
agency. They can relay your report to the National Weather Service
office in Great Falls.

A Severe Thunderstorm Watch remains in effect until 900 PM MDT for
central Montana.

LAT...LON 4623 11084 4630 11109 4664 11093 4649 11054
TIME...MOT...LOC 0008Z 212DEG 19KT 4634 11093

Kredensor

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
610 PM MDT SAT AUG 10 2019

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

0540 PM     HAIL             1 SE MONTANA CITY       46.52N 111.91W
08/10/2019  E0.25 INCH       JEFFERSON          MT   TRAINED SPOTTER

            PEA SIZED HAIL AND HEAVY RAIN.

&&