A Pacific cold front crossed Central Montana, leading to widely scattered showers and isolated thunderstorms. Some of these showers and thunderstorms produced gusty winds in excess of 50 mph.
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 TFX wrote it up.
A Pacific cold front crossed Central Montana, leading to widely scattered showers and isolated thunderstorms. Some of these showers and thunderstorms produced gusty winds in excess of 50 mph.
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 Apr 28, 10:26 PM MST, 13 minutes earlier.
Area Forecast Discussion National Weather Service Great Falls MT 1126 PM MDT Sat Apr 28 2018 ...Updated Aviation Discussion... .UPDATE... Showers and thunderstorms continue to push northward this evening. Most of the storms will exit the region by Midnight, with a few scattered showers possible after Midnight, mainly along the divide and in the far eastern sections of the region. Overnight lows look on track, with just a few minor adjustments. Looking into Sunday, looks like the best area to see precipitation will be Southwest MT during the afternoon hours. A few lightning strikes are possible Sunday, but confidence is low at this time for any storm development. Brusda && .SYNOPSIS... A slow-moving disturbance will affect our region this weekend into early next week. Scattered showers and thunderstorms are possible tonight, and again on Sunday, especially south of Great Falls, as cooler air moves back into the region for a few days. Lower elevation rain and mountain snow showers will continue over the region into early next week, along with below- normal temperatures. Thereafter, an overall warming and drying trend takes hold next week Wednesday through the end of the work week. && .AVIATION... Updated 0526Z. Scattered showers with isolated thunderstorms can be expected to wane through the night. On Sunday, expect lower ceilings with showers and high mountain snow developing over much of Southwest MT, while northwesterly breezes will help limit precipitation chances over the north. Mountains/passes will be obscured at times. CC/Brusda && .HYDROLOGY... An areal flood advisory continues for Meagher County where impacts are currently found near the town of Ringling. A creek flood advisory continues for Tenmile Creek in the Helena valley. Some minor flooding also being reported near Elk Creek by Augusta. Snowmelt from warmer temperatures could cause additional impacts in other locations in Lewis and Clark County. An areal flood warning continues for Blaine County. Widespread impacts continue, with numerous roads affected by flowing water. Water is receding, and impacts should be decreasing by Monday. Brusda && .PREV DISCUSSION... /ISSUED 225 PM MDT Sat Apr 28 2018/ Rest of today through Monday...Main concern for the rest of today and tonight is the potential for scattered showers and isolated thunderstorms as a Pacific cold front sweeps eastward through the predawn hours of Sunday and a 700 mb shortwave trough overspreads the CWA from the west. Weak to moderate instability and primarily moderate vertical wind shear are projected to support organized thunderstorms capable of small to perhaps marginally-severe hail. In addition, any strong storm that develops this afternoon or early evening will likely produce gusty winds. North-Central MT remains the preferred area for stronger storms as greater instability is projected to reside over the region. The primary longwave upper- level trough then overspreads our area Sunday through Monday, resulting in temperatures cooling to near-normal on Sunday and below- normal by Monday. Periods of rain showers at lower elevations and mountain snow showers, particularly above 6000 feet MSL, are expected, especially over Central and Southwest Montana. Orographic effects look to focus the greatest precipitation amounts over these areas. Lastly another round of thunderstorms is possible over Southwest Montana Sunday afternoon and early evening. Modest instability and moderate to strong vertical shear may allow some of these storms to be strong. Jaszka For Sunday night through early next weekend, expect scattered showers to continue Sunday night through Tuesday. The latest models continue the downward trend with forecast precipitation amounts toward the Hi-Line, with perhaps a slight upward trend over the mountains of central and southwest Montana. Temperatures will cool to below normal for the first half of next week. For Wednesday through Saturday, weak upper level ridging will try to build over the region, resulting in a warming and drying trend for our region. CC/Brusda && .PRELIMINARY POINT TEMPS/POPS... GTF 42 62 36 52 / 10 20 50 40 CTB 41 56 34 52 / 30 30 60 40 HLN 42 61 38 53 / 10 40 60 60 BZN 41 60 37 50 / 10 50 80 60 WEY 30 48 28 43 / 20 30 40 50 DLN 36 55 33 48 / 20 70 80 60 HVR 45 67 40 52 / 20 20 30 40 LWT 42 64 36 48 / 20 20 60 40 && .TFX WATCHES/WARNINGS/ADVISORIES... Areal Flood Warning continues for Blaine County until further notice. Areal Flood Advisory continues for Meagher and Lewis and Clark counties until further notice. && http://www.weather.gov/greatfalls
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
1030 PM MDT SAT APR 28 2018
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0914 PM TSTM WND GST HAVRE AP ASOS 48.54N 109.76W
04/28/2018 M52 MPH HILL MT ASOS
&&
MARTINSpecial Weather Statement National Weather Service Great Falls MT 1105 PM MDT SAT APR 28 2018 MTZ051-290530- Fergus MT- 1105 PM MDT SAT APR 28 2018 ...SIGNIFICANT WEATHER ADVISORY FOR CENTRAL FERGUS COUNTY UNTIL 1130 PM MDT... At 1104 PM MDT, Doppler radar was tracking a strong thunderstorm 7 miles north of Lewistown, moving northeast at 15 mph. At 1051 PM, a 51 mph wind gust was measured at the Lewistown Airport. Wind gusts up to 50 mph will remain possible with this storm over the next 15 to 30 minutes. Locations impacted include... Lewistown, Giltedge and Hilger. LAT...LON 4702 10924 4712 10960 4729 10946 4719 10904 TIME...MOT...LOC 0504Z 225DEG 12KT 4717 10939 MARTIN
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
1106 PM MDT SAT APR 28 2018
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1051 PM TSTM WND GST LEWISTOWN ASOS 47.05N 109.47W
04/28/2018 M51 MPH FERGUS MT ASOS
PEAK WIND GUST MEASURED AT THE LEWISTOWN
AIRPORT.
&&
MARTINPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
1126 PM MDT SAT APR 28 2018
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1049 PM NON-TSTM WND GST HAVRE AP ASOS 48.54N 109.76W
04/28/2018 M53 MPH HILL MT ASOS
A CONVECTIVE SHOWER WITH NO LIGHTNING
PRODUCED A STRONG DOWNBURST WIND GUST. IN
ADDITION, THE TEMPERATURE QUICKLY ROSE 7
DEGREES IN 10 MINUTES IMMEDIATELY AFTER THE
WIND GUST.
&&
MARTINSpecial Weather Statement
National Weather Service Great Falls MT
1135 PM MDT SAT APR 28 2018
MTZ047-290630-
Blaine MT-
1135 PM MDT SAT APR 28 2018
...SIGNIFICANT WEATHER ADVISORY FOR CENTRAL AND SOUTHERN BLAINE
COUNTY UNTIL 1230 AM MDT...
At 1132 PM MDT, Doppler radar was tracking a cluster of showers and
isolated thunderstorms 22 miles east of Parker School, or 24 miles
south of Chinook, moving northeast at 30 mph.
Wind gusts of 50 to 55 mph will be possible with these showers and
storms. In addition, a quick rise in temperatures of 5 to 10 degrees
may accompany the strong wind gusts. Rainfall amounts will be very
light.
Locations impacted include...
Chinook, Harlem, Fort Belknap, Lohman, Lloyd, Cleveland and Zurich.
LAT...LON 4793 10928 4805 10954 4822 10953 4823 10955
4829 10955 4830 10952 4844 10950 4846 10946
4850 10947 4873 10931 4850 10853
TIME...MOT...LOC 0532Z 209DEG 25KT 4824 10925
MARTIN1 high wind. Local standard time, as filed.
A shower produced strong outflow winds across portions of Fergus County. The DOT sensor near Denton measured a 58 mph gust.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Montana in 2018Every state in 2018This day in weather historyWarnings in Montana, April 2018
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: 743141.