A low-pressure system and a stalled surface front amid a moderately-unstable atmosphere became the focus for perisistent thunderstorms during the late-night hours, some of which became severe over central portions of northeast Montana.
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.
A low-pressure system and a stalled surface front amid a moderately-unstable atmosphere became the focus for perisistent thunderstorms during the late-night hours, some of which became severe over central portions of northeast Montana.
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 7, 7:44 PM MST, 1 hour 16 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GLASGOW MT 844 PM MDT SUN JUL 7 2013 .SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH TUESDAY... 845PM UPDATE... RAISED POPS ACROSS THE NORTH GIVEN RADAR OBSERVATIONS SHOWING SHOWERS AND THUNDERSTORMS PUSHING INTO THE CWA. THESE STORMS MAY MAKE IT INTO CENTRAL PORTIONS OF THE CWA OVERNIGHT BUT SHOULD WEAKEN IN INTENSITY. SHOWERS AND THUNDERSTORMS ARE ALSO EXPECTED TO CONTINUE TO SLIDE ACROSS THE SOUTHERN ZONES THROUGH LATE THIS EVENING. INSERTED MENTION OF SMALL HAIL...GUSTY WINDS...AND HEAVY RAIN INTO THE GRIDS THROUGH THE EVENING. A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 11PM FOR PETROLEUM...GARFIELD...AND PRAIRIE COUNTIES WHERE A FEW STORMS MAY PRODUCE LARGE HAIL. A BETTER CHANCE FOR SEVERE WEATHER EXISTS FOR THE AFTERNOON AND EVENING ON MONDAY AND THAT WILL BE HANDLED WITH MORE DETAIL WITH THE MORNING PACKAGE. MALIAWCO 400PM UPDATE... SEVERE THUNDERSTORM WATCH ISSUED FOR PETROLEUM...GARFIELD...AND PRAIRIE COUNTIES. THUNDERSTORMS ARE DEVELOPING TO THE WEST AND TO THE SOUTH OF THE CWA AND WILL SLIDE ACROSS THE SOUTHERN ZONES THIS EVENING AND INTO TONIGHT. WILL CONTINUE TO MONITOR FOR STRONG WIND AND LARGE HAIL POTENTIAL IN THESE AREAS...ALONG WITH LOCALLY HEAVY RAINFALL. MALIAWCO ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS OVER THE CENTRAL PORTIONS OF THE CWA SHOULD CONTINUE TO PUSH EASTWARD THROUGH THE CWA FOR THE REST OF THIS AFTERNOON AND EVENING. ADDITIONAL DEVELOPMENT OF STORMS WILL SLIDE ALONG THE SOUTHERN ZONES OVERNIGHT. OTHERWISE EXPECTING TEMPERATURES TO GRADUALLY COOL THIS EVENING...WITH FAIRLY SEASONABLE OVERNIGHT LOWS. MONDAY INTO MONDAY NIGHT...MAIN CONCERN CONTINUES TO BE THE SEVERE WEATHER POTENTIAL SETTING UP ACROSS NORTHEAST MONTANA. VIGOROUS SHORTWAVE DEPICTED IN THE 07/12Z MODEL GUIDANCE TO CUT ACROSS THE PACIFIC NORTHWEST AND ENTER NORTHWESTERN MONTANA DURING THE AFTERNOON AND EVENING HOURS WITH AN ASSOCIATED COLD FRONT. EXPECT THAT THERE SHOULD BE MORE THAN ENOUGH FORCING FOR VERTICAL ASCENT OUT AHEAD OF THIS SYSTEM TO TRIGGER SHOWERS AND THUNDERSTORMS DEVELOPMENT. FORECAST SOUNDINGS INDICATE PRECIPITABLE WATER VALUES OF AROUND AN INCH FOR MOST OF THE AFTERNOON AND INTO THE OVERNIGHT. THEREFORE ANY THUNDERSTORMS COULD BE ACCOMPANIED BY VERY HEAVY RAIN. WITH VERTICAL PROFILES SHOWING NICE DIRECTIONAL WIND SHEAR AND MID LEVEL DRY AIR...WILL NEED TO MONITOR FOR STRONG WINDS AND LARGE HAIL POTENTIAL WITH SOME OF THESE STORMS. IN SHORT...CONVECTIVE PARAMETERS DO CONTINUE TO APPEAR SUPPORTIVE OF CONVECTION WITH SEVERE STORMS POSSIBLE AND SO WILL KEEP MENTION GOING IN THE GRIDS FOR MONDAY AFTERNOON INTO MONDAY NIGHT FOR ENTIRE CWA. ANY LEFTOVER SHOWERS AND THUNDERSTORMS ON TUESDAY WILL SLIDE FROM EAST TO WEST DURING THE DAY AND SO EXPECT CONDITIONS TO DRY. IN THE WAKE OF THE SYSTEM EXPECT SOMEWHAT COOLER TEMPERATURES AS WELL. THEREFORE...TRENDED HIGHS DOWN A FEW DEGREES FROM MONDAY/S EXPECTED READINGS. MALIAWCO .LONG TERM...TUESDAY NIGHT THROUGH SUNDAY... LITTLE CHANGE IN THE EXTENDED PATTERN WITH FAIRLY TYPICAL JULY WEATHER EXPECTED. SHORTWAVE RIDGING EARLY IN THE PERIOD WILL RESULT IN WARM AND GENERALLY DRY CONDITIONS. SHORTWAVE TROF SWINGS INTO CENTRAL CANADA FROM LATE THURSDAY INTO FRIDAY WITH INCREASING POTENTIAL FOR THUNDERSTORMS INTO THE STATE FROM THIS FEATURE ALTHOUGH THERE ARE SOME SIGNIFICANT MODEL DIFFERENCES. THESE MODEL UNCERTAINTIES CONTINUE THROUGH NEXT WEEKEND RESULTING IN A LOW CONFIDENCE...NEAR CLIMATOLOGY FORECAST. EBERT PREVIOUS LONG TERM DISCUSSION...SYNOPTIC SET UP... LONG TERM BEGINS WITH A LARGE HEAT DOME OVER THE DESERT SOUTHWEST AND INTERMOUNTAIN WEST. A RIDGE SPUR IS ANTICIPATED TO JUT OUT OF THE DOME OVER THE HIGH PLAINS OF MONTANA AND ALBERTA. A CLOSED LOW IS EXPECTED OVER THE COAST OF BRITISH COLUMBIA WITH A WEAK TROUGH RUNNING SOUTH JUST OFF THE COAST OF THE PACIFIC NORTHWEST. TUESDAY NIGHT INTO THURSDAY... DRY CONDITIONS ARE ANTICIPATED UNTIL THURSDAY AS NORTHEAST MONTANA REMAINS IN NORTHWEST FLOW WITH A RIDGE INCREASING IN INFLUENCE. THURSDAY... THE AXIS OF THE RIDGE WILL PASS THROUGH AND ALLOW FOR A ISOLATED THUNDERSTORMS TO DEVELOP ON THE AXIS. THURSDAY ALSO LOOKS TO BE VERY WARM AHEAD OF THE AXIS WITH UPPER 90S AND POSSIBLE AS 850 MB TEMPERATURES REACH INTO THE 30* CELSIUS RANGE. THURSDAY NIGHT INTO SATURDAY...CLOSED LOW OVER BRITISH COLUMBIA IS ANTICIPATED TO DROP SOUTH INTO THE PACIFIC NORTHWEST SENDING THE RIDGE OVER THE GREAT PLAINS. THIS WILL PLACE NORTHEAST MONTANA IN A SOUTHWEST FLOW WITH A WEAK TROUGHS AND SHORTWAVES MOVING THROUGH THE FLOW. A SHORTWAVE IS CURRENTLY TIMED ON THURSDAY NIGHT WITH THE BASE OF THE LARGE TROUGH MOVING THROUGH SATURDAY MORNING. HOWEVER... TIMING OF THESE WAVES COULD EASILY SHIFT AS THE LAST COUPLE RUNS HAVE ALREADY MOVED THEM AROUND. SATURDAY NIGHT ONWARD... THE TROUGH IS ANTICIPATED TO PASS OFF TO THE EAST AND REPRESS THE HEAT TO THE SOUTH. THIS WILL GENERATE ZONAL FLOW ACROSS THE NORTHERN TIER OF THE U.S. INCLUDING NORTHEAST MONTANA. CONDITIONS WILL BECOME VERY SIMILAR TO TODAY THROUGH MONDAY WHERE WEAK WAVES WILL PASS THROUGH THE AREA AND TEMPERATURES WILL MODERATE. GAH && .AVIATION... VFR. A FEW THUNDERSTORMS ARE POSSIBLE ACROSS THE REGION THROUGHOUT THE DAY AND OVERNIGHT...WHICH COULD PRODUCE TEMPORARY MVFR/IFR CONDITIONS. MORE WIDESPREAD THUNDERSTORMS ARE LIKELY MONDAY AFTERNOON AND EVENING...AND SOME OF THESE STORMS COULD CONTAIN HAIL OR STRONG WINDS. SCT && .GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE. && WEATHER.GOV/GLASGOW
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE GLASGOW MT 250 PM MDT SUN JUL 7 2013 MTZ016>027-059>062-081000- CENTRAL AND SOUTHEAST PHILLIPS-CENTRAL AND SOUTHERN VALLEY- DANIELS-SHERIDAN-WESTERN ROOSEVELT-PETROLEUM-GARFIELD-MCCONE- RICHLAND-DAWSON-PRAIRIE-WIBAUX-NORTHERN PHILLIPS- SOUTHWEST PHILLIPS-NORTHERN VALLEY-EASTERN ROOSEVELT- 250 PM MDT SUN JUL 7 2013 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHEAST MONTANA. .DAY ONE...THIS AFTERNOON AND TONIGHT THUNDERSTORMS ARE POSSIBLE AS A WEAK FRONT LIFTS NORTH ACROSS MONTANA. SOME OF THE STRONGER STORMS MAY PRODUCE HEAVY RAIN. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY CHANCES FOR SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE THROUGH TUESDAY AS LOW PRESSURE SYSTEM REMAINS IN THE AREA. THE POTENTIAL EXISTS FOR STRONG TO SEVERE THUNDERSTORMS ON MONDAY WITH STRONG WINDS AND HAIL. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GLASGOW MT
854 PM MDT SUN JUL 7 2013
MTZ059-061-080400-
PHILLIPS-VALLEY-
854 PM MDT SUN JUL 7 2013
THE NATIONAL WEATHER SERVICE IN GLASGOW HAS ISSUED A
SIGNIFICANT WEATHER ADVISORY FOR...
NORTHERN VALLEY COUNTY IN NORTHEAST MONTANA...
NORTHEASTERN PHILLIPS COUNTY IN NORTHEAST MONTANA...
UNTIL 1000 PM MDT.
AT 849 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 23 MILES NORTHEAST OF WHITEWATER...MOVING
SOUTHEAST AT 25 MPH.
HAIL UP TO THE SIZE OF PENNIES AND WIND GUSTS UP TO 50 MPH ARE
EXPECTED WITH THIS STORM...ALONG WITH HEAVY RAIN AND FREQUENT
DANGEROUS LIGHTNING.
LOCATIONS NEAR THE PATH OF THIS STORM INCLUDE...OPHEIM.
THIS STORM MAY INTENSIFY...SO BE CERTAIN TO MONITOR LOCAL RADIO AND
INTERNET...FOR ADDITIONAL INFORMATION AND POSSIBLE WARNINGS FROM THE
NATIONAL WEATHER SERVICE.
LAT...LON 4901 10669 4890 10635 4857 10670 4857 10672
4895 10741 4901 10733
TIME...MOT...LOC 0253Z 298DEG 21KT 4894 10718
GAH
WEATHER.GOV/GLASGOWThe Glasgow radar (KGGW), 76 km away, was scanning. The volume nearest the first event began at 04:01 UTC.
4 thunderstorm wind, 1 hail. Local standard time, as filed.
The Bluff Creek RAWS mesonet site recorded a 70 mph wind gust.
Public reported penny-sized hail and 60 mph winds among nearly 2 inches of rainfall in just 20 minutes.
Also had 3/4 hail.
Trained spotter reported significant crop damage from thunderstorm winds and debris near mile marker 34 on Montana Highway 24.
Trained spotter measured a 69 mph wind gust at their home weather station.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Montana in 2013Every state in 2013This day in weather historyWarnings in Montana, July 2013
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: 469316, 469314, 471768, 469315, 469317.