Severe Thunderstorms Bring 60 mph Winds to Montana as Flash Flooding Hits New York

Severe thunderstorms are producing damaging winds in Montana and triggering flash flooding in New York while prolonged flooding continues along the Illinois River.

Active Severe Thunderstorm Warning in Montana

A Severe Thunderstorm Warning is in effect for Fergus County, Montana [1]. At 822 PM MDT, severe thunderstorms were located along a line extending from 11 miles south of Roy to near Grass Range, moving east northeast at 30 mph [1]. The hazard includes 60 mph wind gusts [1]. The source for this information is radar indicated [1]. The impact includes expected damage to roofs, siding, and trees [1]. Locations impacted include Grass Range, Roy, Fergus, and Valentine [1]. The Severe Thunderstorm Warning covers these areas with storms producing 60 mph wind gusts capable of damaging roofs, siding and trees [1]. At 822 PM MDT the line of severe thunderstorms extended from 11 miles south of Roy to near Grass Range while moving east northeast at 30 mph [1]. Radar indicated the presence of these storms and their associated 60 mph wind gusts [1]. Damage to roofs, siding, and trees is expected in the warned area [1]. The communities of Grass Range, Roy, Fergus, and Valentine are among the locations impacted by the warning [1]. The Severe Thunderstorm Warning remains active as the line of storms continues its east northeast movement at 30 mph [1]. Hazards center on 60 mph wind gusts identified through radar [1]. Impacts focus on potential damage to roofs, siding, and trees across the affected zone [1].

Flash Flooding Underway in New York

A Flash Flood Warning has been issued for Orange County, New York [2]. At 1021 PM EDT, Doppler radar and automated rain gauges indicated thunderstorms producing heavy rain across the warned area [2]. Between 2 and 4 inches of rain have fallen [2]. The expected rainfall rate is 1.5 to 2.5 inches in 1 hour [2]. Additional rainfall amounts of 2 to 3 inches are possible in the warned area [2]. Flash flooding is ongoing or expected to begin shortly [2]. The hazard is flash flooding caused by thunderstorms [2]. The source is radar and automated gauges [2]. The impact is flash flooding of small creeks and streams [2]. Between 2 and 4 inches of rain have already fallen in the warned area according to Doppler radar and automated rain gauges [2]. Rainfall rates of 1.5 to 2.5 inches per hour are expected, with an additional 2 to 3 inches possible [2]. Flash flooding is ongoing or expected to begin shortly in the area [2]. The Flash Flood Warning addresses hazards from thunderstorms that have produced these rainfall totals [2]. Radar and automated gauges confirm the heavy rain and support the warning [2]. Impacts center on flash flooding of small creeks and streams [2]. The warning highlights that 2 to 4 inches have fallen with rates of 1.5 to 2.5 inches per hour and further amounts possible [2].

Ongoing Illinois River Flooding

Flood Warnings remain in effect for multiple segments of the Illinois River [3]. The Flood Warning is extended for the Illinois River at Peoria affecting Peoria, Tazewell and Woodford Counties [3]. The Flood Warning continues for the Illinois River at Beardstown affecting Morgan, Cass, Schuyler and Brown Counties [3]. The Flood Warning continues for the Illinois River near Havana affecting Fulton, Cass and Mason Counties [3]. The Flood Warning is extended for the Illinois River at Peoria affecting Peoria, Tazewell and Woodford Counties [4]. The Flood Warning continues for the Illinois River at Beardstown affecting Morgan, Cass, Schuyler and Brown Counties [4]. The Flood Warning continues for the Illinois River near Havana affecting Fulton, Cass and Mason Counties [4]. The Flood Warning is extended for the Illinois River at Peoria affecting Peoria, Tazewell and Woodford Counties [5]. The Flood Warning continues for the Illinois River at Beardstown affecting Morgan, Cass, Schuyler and Brown Counties [5]. The Flood Warning continues for the Illinois River near Havana affecting Fulton, Cass and Mason Counties [5]. Multiple segments of the Illinois River remain under Flood Warning across these counties [3]. The Illinois River at Peoria affects Peoria, Tazewell and Woodford Counties under an extended Flood Warning [3]. The Illinois River at Beardstown affects Morgan, Cass, Schuyler and Brown Counties under a continued Flood Warning [3]. The Illinois River near Havana affects Fulton, Cass and Mason Counties under a continued Flood Warning [3].

Current Storm Impacts and Hazards

Severe thunderstorms are producing damaging winds in Montana while flash flooding occurs in New York and prolonged flooding continues along the Illinois River [1]. The Severe Thunderstorm Warning in Fergus County brings 60 mph wind gusts that can damage roofs, siding and trees in Grass Range, Roy, Fergus and Valentine [1]. At the same time the Flash Flood Warning in Orange County addresses ongoing or imminent flash flooding of small creeks and streams after 2 to 4 inches of rain [2]. Flood Warnings stay active for the Illinois River at Peoria, Beardstown and near Havana, covering counties including Peoria, Tazewell, Woodford, Morgan, Cass, Schuyler, Brown, Fulton and Mason [3]. These simultaneous conditions create combined threats of high winds, flash flooding and river flooding across regions [1]. The 60 mph wind gusts in Montana add structural and tree damage risks while New York experiences flash flooding of small creeks and streams [2]. Extended and continued Flood Warnings along the Illinois River maintain elevated water levels in multiple counties [4]. The hazards occur together as severe thunderstorms move through Montana, heavy rain triggers flash flooding in New York, and river flooding persists in Illinois [5].

Forecast Basis for Warnings

The following forecasts are based on observed precipitation, soil moisture conditions, and forecast precipitation [3]. The Severe Thunderstorm Warning relies on radar indicated sources for the 60 mph wind gusts and storm movement [1]. The Flash Flood Warning draws from Doppler radar and automated rain gauges that showed 2 to 4 inches of rain fallen with rates of 1.5 to 2.5 inches per hour [2]. The Flood Warnings for the Illinois River segments incorporate observed precipitation, soil moisture conditions, and forecast precipitation [3]. These same factors support the extended and continued warnings for the Illinois River at Peoria, Beardstown and near Havana [4]. Observed precipitation, soil moisture conditions, and forecast precipitation form the basis for the river forecasts affecting the listed counties [5]. Radar indicated data underpins the Montana thunderstorm details while radar and automated gauges support the New York rainfall measurements [1].

What to watch next includes continued movement of the severe thunderstorms east northeast at 30 mph in Montana, additional rainfall of 2 to 3 inches possible in the New York warned area, and the ongoing Flood Warnings for the Illinois River segments based on observed precipitation, soil moisture conditions, and forecast precipitation.