Hail in Montana, July 20, 2008

Name: Hail in Montana, July 20, 2008
Start: 2008-07-20T16:10
End: 2008-07-20T16:25
Location: Montana

July 20, 2008 · NWS GGW · 5 events in 1 county or zone

A compact impulse passed through an upper ridge and aided in the development of a few severe thunderstorms.

Where it happened

Every event with a place to put it. Tap one for its entry below.

Tornadoes
Tropical storms and surge
Floods
Wind
Hail
Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
Other

Open the live radar over this ground

The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 5

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.

What happened

The episode as NWS GGW wrote it up.

A compact impulse passed through an upper ridge and aided in the development of a few severe thunderstorms.

What forecasters said that day

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 20, 2:15 PM MST, 1 hour 55 minutes earlier.

Area forecast discussion, Jul 20, 2:15 PM MST, 1 hour 55 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GLASGOW MT
315 PM MDT SUN JUL 20 2008

.SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH TUESDAY...
UPPER RIDGING FROM THE S HAS BROUGHT WARMING...DRYING...AND
STABILIZING OF THE AIRMASS. AT THE SAME TIME THOUGH A WEAK
SHORTWAVE FROM THE WEST IS MOVING RATHER QUICKLY E ACROSS THE AREA
THIS AFTERNOON AND EARLY EVE. THIS HAS TAPPED INTO A PLUME OF
SUBTROPICAL MOISTURE/CLOUDS FROM THE SW STATES HAS WORKED ITS WAY
ALL THE WAY N INTO MT. THIS IS JUST HIGH LEVEL MOISTURE AND TAKING
THE FORM OF JUST CIRRUS. THIS WILL QUICKLY MOVE OUT OF THE AREA
THIS EVE AND SUBTROPICAL FLOW WILL BE CUT OFF.

FURTHER WARMING OF THE AIRMASS TO CONTINUE MON AS THE UPPER
RIDGING INCREASES THICKNESSES AND 850 MB TEMPS CLIMB TO 22-28C
ACROSS OUR AREA...WITH STRONG SURFACE THERMAL TROUGH OVER THE AREA
AND NEARLY CLEAR SKIES. THIS WILL BRING TEMPS INTO THE 90S MOST
LOCATIONS. THE WARMING OF THE AIRMASS CONTINUES TUE AS WELL WITH
THE STRONG SURFACE THERMAL TROUGH OVER THE AREA AND THICKNESSES
WELL INTO THE 580S DM...850 TEMPS FROM 27-30C AND 700 MB TEMPS
11-14C. SUBTROPICAL MOISTURE/ HIGH CLOUDS START TO FLOW INTO THE
AREA BY AFTERNOON THOUGH...SO WILL GO WITH HIGHS SIMILAR TO MON.
MODELS ARE ALL IN GOOD AGREEMENT WITH MOS TEMPS. AIRMASS BECOMES
QUITE A BIT MORE UNSTABLE...BUT CONVECTIVE TEMPS VERY HIGH. ONLY
MODELS THAT HAS QPF BEFORE 00Z WED IS THE NOGAPS. WILL GO WITH
POPS ONLY SW TUE AFTERNOON. SIMONSEN

.LONG TERM...TUESDAY NIGHT THROUGH SUNDAY...
VERY LITTLE CHANGE TO THE EXTENDED PERIOD. UPPER RIDGE WILL
DOMINATE WITH TWO SHORTWAVES OF INTEREST. FIRST ONE WILL BE EARLY
IN THE PERIOD AND MUCH STRONGER THAN THE SECOND...WHICH WILL SLIDE
THROUGH THE RIDGE AT THE END OF THE PERIOD. MONSOON ALSO STARTING
TO PUSH MOISTURE TOWARD MONTANA WHICH WILL AID IN THUNDERSTORM
DEVELOPMENT AHEAD OF THE SHORTWAVES. ADDED POPS TO NEXT SUNDAY ON
ACCOUNT OF THE SECOND SHORTWAVE. EBERT

PREVIOUS LONG TERM DISCUSSION...MODELS CONTINUE TO ADVERTISE A
SHORTWAVE THAT WILL MOVE ALONG THE CANADIAN BORDER AND AFFECT THE
FORECAST AREA TUESDAY NIGHT AND WEDNESDAY. THIS WILL BRING A COLD
FRONT SOUTH ON WEDNESDAY WITH A CHANCE OF THUNDERSTORMS. MODELS
ARE BECOMING MORE GENEROUS WITH THE MOISTURE WITH THIS SYSTEM.
WILL RAISE POPS FROM SLIGHT CHANCE TO CHANCE OF THUNDERSTORMS FOR
TUESDAY NIGHT AND WEDNESDAY. AIRMASS COULD BECOME UNSTABLE ENOUGH
TUESDAY EVENING AND WEDNESDAY AFTERNOON FOR SEVERE THUNDERSTORMS.

UPPER RIDGE BUILDS BACK INTO MONTANA LATE IN THE WEEK WITH WARM AND
MAINLY DRY WEATHER. MODELS HAVE GOOD AGREEMENT ON THE RIDGE BUT
CONTINUE TO DIFFER ON THE TIMING OF ANY SHORTWAVES THAT THEY BRING
ACROSS THE RIDGE. WILL MAINTAIN A DRY FORECAST AT THIS TIME.

&&

.AVIATION...
UPPER WAVE MOVING ACROSS THE STATE IS PUSHING MID LEVEL CLOUDS
ACROSS EASTERN MONTANA THIS AFTERNOON. SKIES WILL CLEAR TONIGHT
AND REMAIN CLEAR INTO MONDAY. WINDS WILL BE MOSTLY LIGHT. RAE

&&

.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

WEATHER.GOV/GLASGOW

In the hours before

Local storm report, Jul 20, 11:11 AM MST, 4 hours 59 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GLASGOW MT
1211 PM MDT SUN JUL 20 2008

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1245 PM     HAIL             9 NW CULBERTSON         48.24N 104.65W
07/19/2008  E0.75 INCH       ROOSEVELT          MT   PUBLIC

            PENNY TO NICKEL SIZE HAIL

&&

JIMB

The radar

The Glasgow radar (KGGW), 234 km away, was scanning. The volume nearest the first event began at 23:09 UTC.

Open the radar archive at this moment

Event by event

5 hail. Local standard time, as filed.

Hail, Wibaux

When: July 20, 4:10 PM MST
Where: Wibaux County, 6 mi S of Wibaux
Measured: 0.75 in hail
Reported by: Public
Coordinates: 46.893, -104.180

Wind gusts were estimated at 50 mph.

Hail, Wibaux

When: July 20, 4:12 PM MST
Where: Wibaux County, 5 mi S of Wibaux
Measured: 0.88 in hail
Reported by: Public
Coordinates: 46.908, -104.180

Hail, Wibaux

When: July 20, 4:14 PM MST
Where: Wibaux County, 7 mi WSW of St Phillip
Measured: 0.88 in hail
Reported by: Trained Spotter
Coordinates: 46.791, -104.217

A measured wind gust to 50 mph accompanied the hail.

Hail, Wibaux

When: July 20, 4:20 PM MST
Where: Wibaux County, 15 mi SSW of Wibaux
Measured: 1 in hail
Reported by: Public
Coordinates: 46.779, -104.302

Hail, Wibaux

When: July 20, 4:25 PM MST
Where: Wibaux County, 19 mi S of Wibaux
Measured: 0.75 in hail
Reported by: Public
Coordinates: 46.705, -104.180

Estimated winds of 45 mph accompanied the hail.

What these are

Hail: Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in Montana in 2008 Every state in 2008 This day in weather history Warnings in Montana, July 2008

Sources

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: 111715, 111716, 111717, 111718, 111719.