A cold front moved eastward into Southwest Montana This was a big change from the day before in which temperatures were in the 60s and low 70s. Most locations saw advisory level criteria, however Homestake Pass reported heavy snow rates and saw accidents due to quickly developing icy conditions.
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 cold front moved eastward into Southwest Montana This was a big change from the day before in which temperatures were in the 60s and low 70s. Most locations saw advisory level criteria, however Homestake Pass reported heavy snow rates and saw accidents due to quickly developing icy conditions.
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 14, 1:50 PM MST, 1 hour 10 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREAT FALLS MT 250 PM MDT TUE APR 14 2015 .DISCUSSION... TONIGHT THROUGH THURSDAY...DEEP UPPER LEVEL TROF CONTINUES TO MOVE ACROSS THE PACIFIC NORTHWEST AND TOWARD WESTERN MONTANA. MODELS CONTINUE TO SHOW THE TROF SPLITTING AS IT CROSSE4S THE CONTINENTAL DIVIDE WITH MOST OF THE ENERGY DIVING SOUTH. A COLD FRONT WILL ACCOMPANY THE TROF PASSAGE AND GUSTY WINDS WILL DEVELOP ALONG AND BEHIND THE FRONT. SOUTHWEST MONTANA REMAINS UNDER THE GREATEST THREAT FOR PRECIPITATION. SNOW AND BLOWING SNOW WILL BE THE GREATEST CONCERN FOR SOUTHWEST MONTANA. SNOW AMOUNTS WILL NOT BE TOO EXTREME, 2 TO 3 INCHES AT LOWER ELEVATIONS, BUT GUSTY WINDS WILL CREATE AREAS OF BLOWING SNOW. MOUNTAINS MAY SEE HIGHER SNOW AMOUNTS. WILL ISSUE A WINTER WEATHER ADVISORY FOR BEAVERHEAD, MADISON, AND GALLATIN COUNTIES FOR OVERNIGHT. AGAIN, BIGGEST IMPACT WILL COME FROM BLOWING SNOW. THE UPPER TROF MOVES QUICKLY TO THE EAST WITH PRECIPITATION ENDING FROM THE NORTH BY MIDDAY. HIGH PRESSURE REBUILDS OVER THE AREA THURSDAY FOR WARMER AND DRY CONDITIONS. TEMPERATURES WILL BE BELOW SEASONAL AVERAGES WEDNESDAY BUT WARM ABOVE SEASONAL AVERAGES THURSDAY. THURSDAY NIGHT THROUGH TUESDAY...DRY THURSDAY NIGHT THROUGH FRIDAY NIGHT UNDER A WESTERLY FLOW ALOFT AS AN UPPER LEVEL RIDGE OVER THE NORTHERN ROCKIES AND MT FLATTENS IN RESPONSE TO SHORTWAVE ENERGY DROPPING SOUTH THROUGH WESTERN CANADA. TEMPERATURES FRIDAY AFTERNOON WILL BE WELL ABOVE AVERAGE WITH WINDS INCREASING FRIDAY AFTERNOON/EVENING AS SURFACE LOW PRESSURE DEVELOPS TO THE LEE OF THE CANADIAN ROCKIES. SMALL WEATHER SYSTEM DROPS SE ACROSS MT SATURDAY AND SATURDAY NIGHT ALONG WITH A COLD FRONT AND COLDER AIRMASS. MEDIUM RANGE MODELS ARE GETTING INTO BETTER AGREEMENT...BUT WAFFLING STILL BEING SEEN ON AMOUNT OF PRECIPITATION WITH GFS NOW SHOWING MORE WIDESPREAD PRECIPITATION THAN THE ECMWF SAT/SAT NIGHT. WEATHER SYSTEM AND LARGER SCALE TROUGH AXIS SHIFTS EAST INTO THE NORTHERN PLAINS STATES SUNDAY THROUGH TUESDAY BUT THE UPPER LEVEL RIDGE AXIS ALONG THE WEST COAST MOVES LITTLE KEEPING THE REGION UNDER A NW FLOW ALOFT FOR DRIER CONDITIONS WITH TEMPERATURES GRADUALLY RETURNING TO SEASONAL AVERAGES EARLY NEXT WEEK.&& .AVIATION... UPDATED 1750Z. STRONG COLD FRONT PUSHING INTO AREAS EAST OF THE CONTINENTAL DIVIDE AND WILL CONTINUE TO MOVE QUICKLY EAST ACROSS CENTRAL AND SW MT BY LATE AFTERNOON. SURFACE WINDS WILL BECOME WESTERLY AS THE FRONT FRONT PASSES, THEN INCREASE SIGNIFICANTLY AND BECOME NORTHWESTERLY THIS AFTERNOON AND EVENING. CLOUDS INCREASE WITH BASES LOWERING AS THE FRONT PASSES FOLLOWED BY SHOWERS DEVELOPING AND SPREADING EAST...INITIALLY OVER THE WEST AND SOUTHWEST MONTANA MOUNTAINS THEN MAINLY ACROSS SW AND CENTRAL MT THIS EVENING AND OVERNIGHT. BY TONIGHT...SNOW LEVELS WILL FALL TO AROUND 4000 FEET WITH A PERIOD OF SNOW POSSIBLE AT CENTRAL AND SW MT TERMINALS. VFR CONDITIONS WILL PREVAIL THROUGH MID AFTERNOON WITH LOCAL MVFR POSSIBLE IN SHOWERS. MVFR CONDITIONS BECOME MORE WIDESPREAD THIS EVENING WITH MOUNTAINS OBSCURED AND LOCAL IFR POSSIBLE IN SNOW AT KLWT AND KBZN. && .PRELIMINARY POINT TEMPS/POPS... GTF 32 50 30 60 / 60 20 0 0 CTB 29 49 29 60 / 60 10 0 0 HLN 30 51 26 62 / 50 30 0 0 BZN 30 46 19 57 / 70 60 0 0 WEY 24 40 17 52 / 100 30 10 0 DLN 25 45 22 57 / 100 30 0 0 HVR 34 55 23 63 / 50 20 0 0 LWT 29 47 24 57 / 80 50 0 0 && .TFX WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY FROM 9 PM WEDNESDAY TO 9 AM MDT THURSDAY FOR BEAVERHEAD...MADISON...GALLATIN. && WEATHER.GOV/GREATFALLS
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
353 PM MDT TUE APR 14 2015
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0346 PM SNOW 12 W WHITEHALL 45.87N 112.35W
04/14/2015 E1.0 INCH JEFFERSON MT PUBLIC
SNOWFALL ACCUMULATION OVER THE LAST HOUR. VISIBILITY
REDUCED TO ZERO AT TIMES WITH BLOWING SNOW.
&&
MARTIN1 winter storm. Local standard time, as filed.
Weather sensors reported wind gusts to 38 mph while snow amounts up to 6 inches were estimated in the higher terrain including Homestake. Two jack-knifed vehicles caused Homestake Pass to be closed for a time around 415 pm MDT.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Montana in 2015Every state in 2015This day in weather historyWarnings in Montana, April 2015
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 2026-09-30. Each event’s entry at NCEI: 565642.