Montana, 2001

Flash Flooding and Hail in Montana, July 1, 2001

July 1, 2001 · NWS BYZ · 20 events in 4 counties and zones

18 hail, 2 flash flood, as filed by the National Weather Service.

Where it happened

Every event with a place to put it; 2 filed by county or forecast zone are drawn at its center, in a lighter ring. 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
20

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 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 Billings, MT wrote its last area forecast discussion before the first event at Jul 1, 1:13 AM MST, 3 hours 54 minutes earlier.

Area forecast discussion, Jul 1, 1:13 AM MST, 3 hours 54 minutes before
SOUTH CENTRAL AND SOUTHEAST MONTANA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BILLINGS MT
213 AM MDT SUN JUL 1 2001

.TDY AND MON...
WARM FRONT TRYING TO LIFT NORTH INTO SOUTHERN MONTANA...BUT LOW LEVEL
COOL STABLE LAYER HOLDING STRONG. WEAK SHORTWAVE TRACKING ACROSS FRONT
PRODUCING A FEW SHOWERS AND THUNDERSTORMS...BUT NOT NEAR AS STRONG AS
LAST FEW NIGHTS. AIRMASS UNSTABLE CLOSER TO BOUNDARY ACROSS NORTHERN
WYOMING...WHERE STRONGER WYOMING STORMS MAY MOVE INTO FAR SOUTHEAST
MONTANA BEFORE 12Z.

FOR TODAY SHORTWAVE RIDGE FOLLOWS WEAK WAVE EXPECTED TO EXIT ZONES THIS
MORNING. AIRMASS UNSTABLE BUT MOSTLY CAPPED ACROSS AREA. ANY CONVECTION
THIS MORNING WILL BE ELEVATED...TYPICAL OF WARM FRONTAL CONVECTION.
AIRMASS REMAINS CAPPED OUT MOST OF DAY AND EVENING. ETA BRINGS WEAK
SHORTWAVE INTO WESTERN ZONES AT 00Z TONIGHT...AND SLOWLY TRACKS IT
ACROSS ZONES OVERNIGHT. SFC TROUGH ALSO SHIFTS INTO CENTRAL MONTANA. ETA
BUFR SOUNDINGS SHOWING CAPE OF OVER 2500 J/KG AT BILLINGS TONIGHT...BUT
CAPPED. CAP EVEN STRONGER IN THE EAST. IF ANYTHING GETS GOING TONIGHT...
IT WILL PROBABLY BE SEVERE. WILL TAKE CONSERVATIVE APPROACH WITH LOW
SCATTERED POPS FOR NOW...SPLY WITH NO STRONG FORCING.

UPPER RIDGE CONTINUES TO BUILD INTO AREA MONDAY...AND AIRMASS BECOMES
MUCH MORE DRY AND STABLE AS WEAK FRONT PUSHES THROUGH MONDAY MORNING.
DEWPOINTS WILL BE MUCH LOWER MOST OF FORECAST AREA...WITH MOSTLY SUNNY
SKIES. WARMER TEMPS WILL BE REALIZED ALSO WITH DRY ADIABATIC LAPSE
RATES. SCARLETT

.TUE...WED...THU...FRI...SAT...
NO CHANGES TO GOING FORECAST. PATTERN BECOMING DRY AFTER THIS PAST
STORMY WEEK WITH A RIDGE OVER THE STATE. RIDGE BREAKS DOWN TOWARDS
THURSDAY AND ISOLATED POPS LOOK GOOD. BORSUM

    TDY MON     TUE     WED     THU     FRI     SAT
-------------------------------------------------------
BIL 083 061/089 056/089 057/087 057/087 054/087 059/087
    2/T 30/U    00/B    01/B    20/B    22/B    11/B
LVM 088 058/091 052/087 053/087 052/087 050/087 055/087
    2/T 30/U    00/B    01/B    20/B    22/B    11/B
HDN 083 059/091 054/091 055/089 053/088 051/088 063/090
    2/T 30/U    00/B    01/B    20/B    22/B    11/B
MLS 079 059/091 060/088 059/085 055/085 054/085 059/085
    2/T 30/B    00/B    01/B    00/B    22/B    11/B
4BQ 080 060/090 058/087 057/084 054/084 053/084 058/088
    2/T 30/B    00/B    01/B    00/B    22/B    11/B
BHK 075 058/088 055/086 055/0(83 053/083 052/083 054/083
    2/T 30/B    00/B    01/B    00/B    22/B    11/B
SHR 089 060/090 054/090 052/088 051/086 050/086 051/086
    2/T 20/B    00/B    01/B    00/B    22/B    11/B

The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

18 hail, 2 flash flood. Local standard time, as filed.

Hail, Custer

When
July 1, 5:07 AM MST
Where
Custer County, Miles City
Measured
1 in hail
Reported by
TRAINED SPOTTER
Coordinates
46.400, -105.833

Hail, Custer

When
July 1, 5:10 AM MST
Where
Custer County, 1 mi E of Miles City
Measured
1.25 in hail
Reported by
TRAINED SPOTTER
Coordinates
46.400, -105.817

Hail, Custer

When
July 1, 5:12 AM MST
Where
Custer County, 3 mi NE of Miles City
Measured
1.25 in hail
Reported by
TRAINED SPOTTER
Coordinates
46.433, -105.783

Hail, Custer

When
July 1, 5:25 AM MST
Where
Custer County, 10 mi E of Miles City
Measured
1.25 in hail
Reported by
TRAINED SPOTTER
Coordinates
46.400, -105.617

Hail, Custer

When
July 1, 6:05 AM MST
Where
Custer County, Mizpah
Measured
1 in hail
Reported by
TRAINED SPOTTER
Coordinates
46.250, -105.267

Hail, Custer

When
July 1, 6:10 AM MST
Where
Custer County, 15 mi S of Mizpah
Measured
2 in hail
Reported by
TRAINED SPOTTER
Coordinates
46.033, -105.267

Hail, Custer

When
July 1, 6:17 AM MST
Where
Custer County, 20 mi SW of Mizpah
Measured
1 in hail
Reported by
TRAINED SPOTTER
Coordinates
46.050, -105.567

Hail, Carter

When
July 1, 6:45 AM MST
Where
Carter County, 15 mi NW of Ekalaka
Measured
1 in hail
Reported by
TRAINED SPOTTER
Coordinates
46.033, -104.767

Hail, Carter

When
July 1, 7:01 AM MST
Where
Carter County, 15 mi E of Ekalaka
Measured
1 in hail
Reported by
TRAINED SPOTTER
Coordinates
45.883, -104.233

Hail, Carter

When
July 1, 7:10 AM MST
Where
Carter County, Ekalaka
Measured
0.75 in hail
Reported by
TRAINED SPOTTER
Coordinates
45.883, -104.550

Hail, Carter

When
July 1, 7:16 AM MST
Where
Carter County, 6 mi S of Ekalaka
Measured
1 in hail
Reported by
TRAINED SPOTTER
Coordinates
45.800, -104.550

Hail, Carter

When
July 1, 7:37 AM MST
Where
Carter County, Belltower
Measured
1 in hail
Reported by
TRAINED SPOTTER
Coordinates
45.633, -104.383

Hail, Stillwater

When
July 1, 8:00 PM MST
Where
Stillwater County, 4 mi SW of Nye
Measured
0.75 in hail
Reported by
TRAINED SPOTTER
Coordinates
45.417, -109.883

Hail, Musselshell

When
July 1, 9:00 PM MST
Where
Musselshell County, 20 mi N of Roundup
Measured
0.75 in hail
Reported by
TRAINED SPOTTER
Coordinates
46.733, -108.533

Hail, Musselshell

When
July 1, 9:25 PM MST
Where
Musselshell County, 12 mi N of Roundup
Measured
0.75 in hail
Reported by
LAW ENFORCEMENT
Coordinates
46.617, -108.533

Hail, Musselshell

When
July 1, 9:55 PM MST
Where
Musselshell County, 13 mi NE of Roundup
Measured
0.75 in hail
Reported by
TRAINED SPOTTER
Coordinates
46.583, -108.333

Flash Flood, Musselshell

When
July 1, 11:00 PM MST
Where
Musselshell County, 10 mi N of Roundup
Reported by
TRAINED SPOTTER
Coordinates
46.497, -108.398 (the zone’s center; the record gives no point)

Water covered the roadways

Hail, Musselshell

When
July 1, 11:00 PM MST
Where
Musselshell County, 10 mi N of Roundup
Measured
0.75 in hail
Reported by
TRAINED SPOTTER
Coordinates
46.600, -108.533

Hail, Musselshell

When
July 1, 11:05 PM MST
Where
Musselshell County, 9 mi NW of Roundup
Measured
0.75 in hail
Reported by
TRAINED SPOTTER
Coordinates
46.550, -108.667

Flash Flood, Musselshell

When
July 1, 11:55 PM MST
Where
Musselshell County, 10 mi N of Roundup
Reported by
TRAINED SPOTTER
Coordinates
46.497, -108.398 (the zone’s center; the record gives no point)

Water continued to cover the roadways and the reservoirs were overflowing.

What these are

Hail
Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.
Flash Flood
Flooding that begins within six hours of the rain that causes it, or of a dam or levee failure or ice jam release, often with deadly speed.

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

The same day elsewhere

More

Every storm in Montana in 2001Every state in 2001This day in weather historyWarnings in Montana, July 2001

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: 5258986, 5258987, 5258988, 5258989, 5258990, 5258991, 5258992, 5258993, 5258994, 5258995, 5258996, 5258997, 5258998, 5259090, 5258999, 5259000, 5259091, 5259092, 5259093, 5259094.