Strong daytime heating ahead of an approaching cold front allowed strong to severe thunderstorms to develop. Thunderstorms near the Phillips/Valley County line produced a squall line which quickly moved east through most of Valley County.
Every event with a place to put it. Tap one for its entry below.
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.
The episode as NWS GGW wrote it up.
Strong daytime heating ahead of an approaching cold front allowed strong to severe thunderstorms to develop. Thunderstorms near the Phillips/Valley County line produced a squall line which quickly moved east through most of Valley County.
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 Glasgow, MT wrote its last area forecast discussion before the first event at Aug 24, 1:38 PM MST, 6 hours 46 minutes earlier.
Area Forecast Discussion National Weather Service Glasgow MT 238 PM MDT Thu Aug 24 2017 .SHORT TERM...for northeast Montana...tonight through Fri... Hot and dry weather conditions are continuing this afternoon across northeast Montana ahead of an approaching cold front. Highs are topping out into the low to middle 90s across the area with gusty south to southeast winds. As the front approaches tonight, expect scattered showers and isolated thunderstorms. Individual storms pay produce up to a tenth of an inch of QPF, though average rainfall will be less overall. Lingering showers will exit the area on Friday into the Dakotas. As this happens, temperatures will be lower in the wake of the frontal passage by about 10 to 15 degrees, with highs in the upper 70s to mid 80s. Maliawco .LONG TERM...Fri night through Thu... The forecast is picked up Friday night with an upper trough well to the north and upper high pressure well to the south. This leaves Northeast Montana under a zonal flow aloft. There is an embedded disturbance in the flow, associated with the Canadian trough, that will ride through just north of our area causing a weak boundary to fluctuate. The result could be a few showers and thunderstorms overnight and into the morning. The upper ridge, which had been over the ocean, shifts east Saturday to cause the upper flow to veer to the northwest. Expect near normal temperatures. The ridge axis slowly drifts east for Sunday, then remains in place through mid-week. Temperatures will ramp higher than normal. Tuesday will see a weak, dry front depress the boundary south near the international border to knock temperatures down closer to normal. Sometime Thursday night or Friday the models hint at another short-wave disturbance sneaking through the prairie provinces, which could generate a few showers with thunder, and maybe some wind, but that is not yet certain. Templer Previous discussion - Upper trof pushes into central Canada with the main low pressure lifting toward the Arctic Friday night. Enough instability in the northwest flow behind the trof for a few showers on Saturday. Ridge then begins rebounding across the Great Basin into early next week. Dry weather with warming temperatures expected for Sunday and Monday. A weak shortwave sliding through Canada will suppress the ridge slightly on Tuesday pushing a dry backdoor front into northern Montana. No precipitation is expected but temperatures should drop a few degree. Ebert && .AVIATION... VFR conditions will prevail tonight with south to southeast winds 10 to 20 kts in the evening, becoming northwest at around 10 kts after 06Z with a cold frontal passage. Scattered showers with isolated thunder will push across the region tonight before exiting into the Dakotas on Friday. Maliawco && .FIRE WEATHER... Hot and dry conditions will continue through early evening hours with highs in the 90s and minimum RH values below 20 percent. This will occur in the presence of gusty south to southeast winds, leading to elevated fire weather conditions. Scattered showers and isolated thunderstorms will occur tonight with a wind switch to the northwest as a cold front pushes across the area tonight. Any storms may elevate fire conditions due to lightning, though recovering relative humidity readings should reduce potential impacts. Additionally, at this time northwest winds behind the front are expected to be somewhat lighter than the south to southeast winds in advance of this system. Nevertheless, winds could still be a big gusty and erratic in and near any thunderstorms that occur. As a result, messaging will continue for elevated fire weather conditions this afternoon into tonight, but no headlines are expected due to the marginal nature of this setup. Drier weather conditions and warming temperatures are once again expected late in the weekend into next week with an upper level ridge building across the western U.S. and amplifying into eastern Montana. Maliawco && .GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE. && weather.gov/glasgow
Special Weather Statement National Weather Service Glasgow MT 746 PM MDT THU AUG 24 2017 MTZ016-017-059-061-250215- Central and Southeast Phillips MT-Northern Valley MT- Northern Phillips MT-Central and Southern Valley MT- 746 PM MDT THU AUG 24 2017 ...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN PHILLIPS AND NORTHWESTERN VALLEY COUNTIES UNTIL 815 PM MDT... At 746 PM MDT, Doppler radar was tracking a strong thunderstorm 7 miles southwest of Saco, or 18 miles east of Malta, moving northeast at 35 mph. Winds in excess of 40 mph will be possible with this storm. Locations impacted include... Saco, Frenchman Reservoir, Bowdoin and Sleeping Buffalo. LAT...LON 4875 10699 4829 10740 4836 10765 4886 10736 TIME...MOT...LOC 0146Z 205DEG 29KT 4840 10748 TFJ
Special Weather Statement National Weather Service Glasgow MT 748 PM MDT THU AUG 24 2017 MTZ022-250215- Garfield MT- 748 PM MDT THU AUG 24 2017 ...SIGNIFICANT WEATHER ADVISORY FOR CENTRAL GARFIELD COUNTY UNTIL 815 PM MDT... At 748 PM MDT, Doppler radar was tracking a strong thunderstorm 7 miles west of Jordan, moving north at 30 mph. Winds in excess of 40 mph will be possible with this storm. Locations impacted include... Jordan. PRECAUTIONARY/PREPAREDNESS ACTIONS... 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. && LAT...LON 4720 10697 4725 10722 4762 10712 4754 10674 TIME...MOT...LOC 0148Z 197DEG 24KT 4730 10707 TFJ
Special Weather Statement
National Weather Service Glasgow MT
753 PM MDT THU AUG 24 2017
MTZ022-026-250230-
Garfield MT-Prairie MT-
753 PM MDT THU AUG 24 2017
...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN GARFIELD AND
NORTHWESTERN PRAIRIE COUNTIES UNTIL 830 PM MDT...
At 752 PM MDT, Doppler radar was tracking a strong thunderstorm near
Hillside, or 34 miles southeast of Jordan, moving north at 30 mph.
Winds in excess of 40 mph will be possible with this storm.
Locations impacted include...
Cohagen and Hillside.
LAT...LON 4685 10664 4723 10661 4716 10606 4684 10627
4684 10656
TIME...MOT...LOC 0152Z 189DEG 26KT 4691 10649
TFJSpecial Weather Statement National Weather Service Glasgow MT 813 PM MDT THU AUG 24 2017 MTZ017-022-023-250300- Garfield MT-McCone MT-Central and Southern Valley MT- 813 PM MDT THU AUG 24 2017 ...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN GARFIELD... SOUTHWESTERN VALLEY AND NORTHWESTERN MCCONE COUNTIES UNTIL 900 PM MDT... At 813 PM MDT, Doppler radar was tracking strong thunderstorms along a line extending from 19 miles north of Brusett to near Hell Creek Rec Area. Movement was northeast at 40 mph. Winds in excess of 40 mph will be possible with these storms. Locations impacted include... Fort Peck, The Pines Rec Area, Fort Peck Marina, Hell Creek Rec Area, Duck Creek Rec Area, Haxby and Park Grove. LAT...LON 4824 10679 4793 10612 4749 10685 4772 10736 TIME...MOT...LOC 0213Z 222DEG 36KT 4770 10725 4755 10692 TFJ
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GLASGOW MT
819 PM MDT THU AUG 24 2017
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0755 PM TSTM WND GST 7 SE DEVILS CREEK REC A 47.55N 107.54W
08/24/2017 M56 MPH GARFIELD MT MESONET
SOUTH SAWMILL RAWS
&&
TEDJPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GLASGOW MT
838 PM MDT THU AUG 24 2017
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0640 PM NON-TSTM WND GST 17 N WINNETT 47.25N 108.35W
08/24/2017 M52 MPH PETROLEUM MT MESONET
DRY BLOOD CREEK RAWS
&&
TEDJThe Glasgow radar (KGGW), 1 km away, was scanning. The volume nearest the first event began at 03:24 UTC.
2 thunderstorm wind. Local standard time, as filed.
A 63 mph wind gust was measured as the Glasgow Airport ASOS.
The Saint Marie MARCO site measured a 67 mph thunderstorm wind gust. Time is estimated by radar.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Montana in 2017Every state in 2017This day in weather historyWarnings in Montana, August 2017
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: 716373, 716385.