High Wind in Montana, July 24, 2019

Name: High Wind in Montana, July 24, 2019
Start: 2019-07-24T12:08
End: 2019-07-24T12:08
Location: Montana

July 24, 2019 · NWS TFX · 1 event in 1 county or zone

The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 1

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS TFX wrote it up.

A ridge of high pressure was flattened by an approaching trough of low pressure situated over British Columbia and eastern Alberta. A strong westerly cross barrier flow then developed over the Rocky Mountain Front. Winds in the upper levels were unseasonably strong, with 300 mb wind speeds around 80 kts. This resulted in surface winds approaching and in some cases exceeding 60 mph over north-central Montana.

What forecasters said that day

The local office's own words before the first event, 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 the first event at Jul 24, 10:49 AM MST, 1 hour 19 minutes earlier.

Area forecast discussion, Jul 24, 10:49 AM MST, 1 hour 19 minutes before

Area Forecast Discussion
National Weather Service Great Falls MT
1149 AM MDT Wed Jul 24 2019

UPDATED AVIATION

.UPDATE...

Most of today's forecast, including the Red Flag Warning for much
of the CWA, remains valid. Freshened hourly temperatures and other
pertinent variables (e.g. dew points) through noontime to better
match observed trends. Also freshened POPs to better match our
neighboring offices' POPs. Cannot rule-out a few showers along the
Rocky Mountain Front through this early afternoon as a
northeastward-moving shortwave trough brushes that area.
Otherwise, a few showers and weak thunderstorms may develop via
daytime heating of higher terrain in central and southwest MT this
afternoon through early evening. The rest of our CWA will likely
remain dry courtesy of westerly and gusty downslope winds behind
a Pacific cool front. At time of writing, this front extended
south-southwestward from just east of Cut Bank to just west of
Great Falls and Dillon. This front will continue moving eastward
and should exit north-central MT by noontime and southwest MT by 3
PM this afternoon.
- Jaszka

&&

.SYNOPSIS...

Wednesday is forecast to be a bit cooler with strong gusty winds and
very low relative humidity. Warmer temperatures return for the
weekend along with a chance for thunderstorms Friday and Saturday in
southwest Montana. With hot, dry and windy conditions forecast,
please use caution as new fires igniting in low elevation grassy
areas will be difficult to contain.

&&

.AVIATION...
Updated 1149 AM MDT Wed Jul 24 2019 (24/18Z TAFs)

VFR expected next 24-hours as westerly flow aloft persists.
Simultaneously, a mid- to upper-level low centered over southeast BC
moves east-northeastward to central SK by 18Z/Thurs. At the surface,
a dry cool front extended south-southwestward from halfway between
KCTB and KHVR to just west of KGTF and KDLN. This front continues to
move eastward and should exit north-central MT by about 20Z/Wed and
southwest MT by about 00Z/Thurs. Primarily southwesterly and gusty
surface winds shift to westerly with the passage of this front. The
westerly winds should then ease between 00Z and 03Z/Thurs. Lastly, a
few showers and thunderstorms may occur over/near the higher terrain
of central and southwest Montana this afternoon and early evening.
- Jaszka

&&

.PREV DISCUSSION...
/ISSUED 402 AM MDT Wed Jul 24 2019/

Wednesday...A trough moves eastward across Montana's northern border
with Canada, removing mass from the ridge that has been dominating
the area. This sets up a westerly cross barrier flow. Expect strong
gusty winds, today. Although temperatures will be a bit cooler than
the past couple of days, conditions remain sufficiently warm and dry
to cause fire weather concerns; therefore, a Red Flag Warning has
been issued. Please, use caution as new fires igniting in low
elevation grassy areas will be difficult to contain.
- Fogleman

Thursday through Saturday...Temperatures warm again for the weekend
with afternoon and evening thunderstorms expected on Friday and
Saturday in southwest Montana compliments of a trough passing to our
south. Relative humidity remains low with little to no precipitation
forecast. Fire weather remains a concern.

Sunday through Wednesday...Sunday, the leading edge of a weak ridge
moves some cooler air into The Treasure State from western Canada
allowing for some relatively cooler temperatures for the day, but as
the ridge builds gradually into the area, a southwesterly flow sets
up, and temperatures warm, again. Hot, dry and windy weather
continues as my extended discussion comes to an end for now.
- Fogleman

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  85  50  85  52 /   0   0   0   0
CTB  77  49  81  49 /   0   0   0   0
HLN  85  49  87  52 /   0   0   0   0
BZN  88  47  86  49 /  10  10   0   0
WEY  83  41  81  42 /  30  10   0   0
DLN  83  46  83  49 /   0   0   0   0
HVR  90  53  87  53 /   0   0   0   0
LWT  88  48  83  50 /  10   0   0   0

&&

.TFX WATCHES/WARNINGS/ADVISORIES...

Red Flag Warning from noon today to 10 PM MDT this evening
Central and Eastern Lewis and Clark National Forest Areas...
Chouteau and Fergus Counties...Eastern
Glacier/Toole/Central/Eastern Pondera/Liberty...Helena and
Townsend Ranger Districts of the Helena National Forest...Hill
and Blaine Counties...Lewis and Clark National Forest Rocky
Mountain District-Rocky Mountain Front.

&&

http://www.weather.gov/greatfalls

In the hours before

Local storm report, Jul 24, 7:09 AM MST, 4 hours 59 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
809 AM MDT WED JUL 24 2019

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

0930 PM     TSTM WND GST     6 WSW HAVRE             48.50N 109.80W
07/23/2019  E54 MPH          HILL               MT   TRAINED SPOTTER

            54 MPH WIND GUST AT THE FORT ASSINNIBOINE
            AGRICULTURAL RESEARCH CENTER.

&&

BRUSDA

Local storm report, Jul 24, 7:19 AM MST, 4 hours 49 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
819 AM MDT WED JUL 24 2019

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

0950 PM     HAIL             HAVRE                   48.54N 109.68W
07/23/2019  NAN INCH         HILL               MT   TRAINED SPOTTER

            CORRECT TIME OF REPORT. ESTIMATED NICKEL
            SIZE HAIL AND ESTIMATED WIND GUSTS NEAR 55
            MPH. TORRENTIAL RAIN AND FREQUENT LIGHTNING.

&&

BRUSDA

Local storm report, Jul 24, 7:29 AM MST, 4 hours 39 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
829 AM MDT WED JUL 24 2019

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

0950 PM     HAIL             HAVRE                   48.54N 109.68W
07/23/2019   0.88 INCH       HILL               MT   TRAINED SPOTTER

            CORRECTS PREVIOUS HAIL REPORT FROM HAVRE.
            ESTIMATED NICKEL SIZE HAIL AND ESTIMATED
            WIND GUSTS NEAR 55 MPH. TORRENTIAL RAIN AND
            FREQUENT LIGHTNING.

&&

Local storm report, Jul 24, 7:30 AM MST, 4 hours 38 minutes before

PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE GREAT FALLS MT
830 AM MDT WED JUL 24 2019

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

0700 PM     HAIL             1 E GREAT FALLS         47.51N 111.27W
07/23/2019  M0.50 INCH       CASCADE            MT   NWS EMPLOYEE

            HALF INCH HAIL WITH ESTIMATED 40 MPH WIND
            GUST.

0750 PM     HEAVY RAIN       CARTER                  47.78N 110.96W
07/23/2019  E1.60 INCH       CHOUTEAU           MT   PUBLIC

            CORRECTS PREVIOUS HEAVY RAIN REPORT FROM
            CARTER. 1.6 INCHES OF RAIN IN LESS THAN 10
            MINUTES.

0831 PM     TSTM WND GST     1 E GREAT FALLS         47.51N 111.26W
07/23/2019  E40 MPH          CASCADE            MT   NWS EMPLOYEE

            HALF INCH HAIL WITH ESTIMATED 40 MPH WIND
            GUST.

0930 PM     TSTM WND GST     6 WSW HAVRE             48.50N 109.80W
07/23/2019  E54 MPH          HILL               MT   TRAINED SPOTTER

            54 MPH WIND GUST AT THE FORT ASSINNIBOINE
            AGRICULTURAL RESEARCH CENTER.

0938 PM     TSTM WND GST     4 W HAVRE               48.54N 109.76W
07/23/2019  M64 MPH          HILL               MT   ASOS

            64 MPH THUNDERSTORM WIND GUST AT THE HAVRE
            ASOS.

0950 PM     HAIL             HAVRE                   48.54N 109.68W
07/23/2019   0.88 INCH       HILL               MT   TRAINED SPOTTER

            CORRECTS PREVIOUS HAIL REPORT FROM HAVRE.
            ESTIMATED NICKEL SIZE HAIL AND ESTIMATED
            WIND GUSTS NEAR 55 MPH. TORRENTIAL RAIN AND
            FREQUENT LIGHTNING.

1015 PM     TSTM WND GST     18 NNW HAVRE            48.78N 109.83W
07/23/2019  M62 MPH          HILL               MT   MESONET

            62 MPH WIND GUST, NEAR HILL COLONY.

1130 PM     TSTM WND GST     18 NNE ROY              47.59N 108.87W
07/23/2019  M53 MPH          FERGUS             MT   MESONET

            MESONET STATION ARMM8 ARMELLS CREEK RAWS. 53
            MPH WIND GUST. TIME OF EVENT IS ESTIMATED.

&&

Local storm report, Jul 24, 11:23 AM MST, 45 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
1223 PM MDT WED JUL 24 2019

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

1100 AM     NON-TSTM WND GST 8 SE EAST GLACIER PARK  48.36N 113.11W
07/24/2019  M55 MPH          GLACIER            MT   MESONET

            WIND GUST OF 55 MPH AT THE DEEP CREEK RAWS
            LOCATION. TIME OF EVENT IS ESTIMATED.

&&

BRUSDA

Local storm report, Jul 24, 12:01 PM MST, 7 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
101 PM MDT WED JUL 24 2019

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

1215 PM     NON-TSTM WND GST 8 SE EAST GLACIER PARK  48.36N 113.11W
07/24/2019  M64 MPH          GLACIER            MT   MESONET

            64 MPH WIND GUST AT THE DEEP CREEK RAWS
            LOCATION. TIME OF EVENT IS ESTIMATED.

&&

BRUSDA

Event by event

1 high wind. Local standard time, as filed.

High Wind, Cascade

When: July 24, 12:08 PM MST
Where: Cascade forecast zone
Measured: 52 kt (60 mph) estimated gust
Reported by: Official NWS Observations

A non-thunderstorm wind gust of 60 mph was reported at the Great Falls WFO.

What these are

High Wind: Sustained non-thunderstorm winds of 40 mph or more for an hour, or gusts of 58 mph or more.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in Montana in 2019 Every state in 2019 This day in weather history Warnings in Montana, July 2019

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 842692.