A disturbance moving across the area produced a few showers and thunderstorms, one of which produced severe hail and a short-lived, weak tornado.
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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.
A disturbance moving across the area produced a few showers and thunderstorms, one of which produced severe hail and a short-lived, weak tornado.
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 Jul 29, 1:08 PM MST, 3 hours 47 minutes earlier.
Area Forecast Discussion National Weather Service Glasgow MT 208 PM MDT Sat Jul 29 2017 .SHORT TERM...for northeast Montana...tonight through Mon... Disturbance moving across the CWA this afternoon has flattened the upper ridge across the area and provided some relief from the searing heat. But the disturbance moves to the east tonight, allowing the sun to heat things back up for Sunday. Clouds were abundant across the CWA this afternoon with most of the showers from Garfield to Dawson/Richland counties. Instability axis was just east of the Montana/North Dakota border with a surface trough signaled by a broken line of strong/severe storms. Clouds will move out tonight to our east allowing for a mostly clear skies tonight. Sunday will be sunny with generally light winds under the ridge. A surface low will enter SW Sask and bring a dry-line or trough across north-central Montana. But it is not expected to reach the NW zones, so no worries in regards to Fire Weather here. See Fire Weather Discussion below for more details. TFJ .LONG TERM...Mon night through Sat... The inherited forecast for the extended period remains largely on track, though temperatures were trended lower for Tuesday into the second half of next week to come into better alignment with the 12z consensus model blend guidance. This should occur as the upper ridge across the western U.S., while remaining amplified into British Colombia and Alberta, becomes narrower. This will lead to lowering 500mb heights across eastern Montana with north to northwest upper flow for much of next week. Maliawco Previous Long Term Discussion... The general upper-level flow pattern in the extended forecast period continues to show a strong ridge of high pressure over the US Great Basin and a substantial trough of low pressure anchored over Hudson Bay. As these two features jockey for position, NE Montana finds itself mostly under the influence of the high pressure ridge, but occasionally, a few small scale disturbances riding around the far side of the ridge, or down the leading side of the trough, could bring a few periods of scattered rain showers and isolated thunderstorms to portions of our CWA. These chances for limited precipitation seem lined up the best on Monday evening over our southern and SE zones, and on Wednesday evening over our NE zones. Otherwise, model discrepancies are too great to allow for such confidence. Throughout the extended forecast period, winds look to be of no great consequence, all at or below 15 mph. A bit of a cool front seems evident in the model data leading into the middle part of the week. BMickelson && .AVIATION... VFR conditions will prevail through the night. Expect isolated to widely scattered thunderstorms near KOLF, KSDY, and KGDV at times through 04Z before ending as they shift east into North Dakota. Light south winds will develop after 06Z and persist through the remainder of the weekend. Maliawco && .FIRE WEATHER... Isolated showers and clouds will depart the area this evening with clear skies and light southeast winds tonight. An upper ridge will build back into the area Sunday, allowing for sunshine to heat the area well into the 90s tomorrow. South then southwest winds will increase over zone 134, but not expecting them to be of concern. Monday will see a wind shift to the west then north along with lowering temperatures. The cooler conditions will last through midweek. TFJ && .GLASGOW WATCHES/WARNINGS/ADVISORIES... && weather.gov/glasgow
The Glasgow radar (KGGW), 187 km away, was scanning. The volume nearest the first event began at 23:56 UTC.
1 tornado, 1 hail. Local standard time, as filed.
Initially reported by Sheridan County dispatch, a small short-lived rope tornado was observed. This was further verified by additional reports and photos.
Public reported, via social media, golf ball sized hail.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Montana in 2017Every state in 2017This day in weather historyThe tornado archive for Montana, 2017Warnings in Montana, July 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: 708589, 708588.