Alert archive / Montana / Flash Flood Warnings in 2021

Flash Flood Warning 1, NWS Billings, MT

June 5, 2021Musselshell County, Montana

NWS Billings, MT issued this flash flood warning at Jun 5, 2021, 4:03 PM MDT for Musselshell County, Montana. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jun 5, 2021, 4:03 PM MDT (22:03 UTC)
Expired
Jun 5, 2021, 7:00 PM MDT
In force
3 hr
Issued by
NWS Billings, MT
Area
Storm-based polygon
Flood severity
None

County Musselshell County, MT

The radar

The Billings radar (KBLX), 60 km from the middle of the area, began a volume at 22:04 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Great_falls, MT (KTFX), launched 12:00Z, 10.1 hours before the alert went out and 208 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Great_falls, MT at 12:00Z on 2021-06-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Great_falls, MT at 12:00Z on 2021-06-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 102 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
3187 m above ground
0-6 km bulk shear
41 kt
0-1 km storm-relative helicity
102 m²/s²
0-3 km storm-relative helicity
83 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

290 
WGUS55 KBYZ 052203
FFWBYZ
MTC065-060100-
/O.NEW.KBYZ.FF.W.0001.210605T2203Z-210606T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Billings MT
403 PM MDT Sat Jun 5 2021

The National Weather Service in Billings has issued a

* Flash Flood Warning for...
  The BobCat Burn Area in...
  Central Musselshell County in central Montana...

* Until 700 PM MDT.

* At 403 PM MDT, Doppler radar indicated thunderstorms producing 
  heavy rain approaching the BobCat Burn Area. The expected rainfall 
  rate is 0.5 to 1 inch in 1 hour. Flash flooding is possible 
  shortly.

Excessive rainfall over the burn scar may result in debris flow 
moving through the Halfbreed Creek, East Parrot Creek, Parrot Creek, 
West Parrot Creek, Musselshell River, Cow Gulch, Railroad Creek, 
Fattig Creek, and Rehder Coulee.

Roads that may be impacted include Highway 87, Beard Road, West 
Parrot Creek Road, East Parrot Creek Road, Fattig Creek Road, Rehder 
Road. The debris flow can consist of rock, mud, vegetation and other 
loose materials.

  HAZARD...Flash flooding caused by thunderstorms in and around
           the BobCat Burn Area.

  SOURCE...Radar.

  IMPACT...Flooding of areas in and downstream of the BobCat Burn
           Area.

* Some locations that will experience flash flooding include...
  Klein.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain alert for flooding of creeks, streams, and normally dry 
coulees even in areas not receiving rainfall downstream of the burn 
area.

Please report observed flooding to local emergency officials and 
request they pass the information to the National Weather Service in 
Billings.

&&

LAT...LON 4627 10839 4626 10844 4631 10849 4635 10850
      4638 10855 4643 10857 4643 10855 4644 10851
      4646 10846 4647 10835 4650 10828 4651 10824
      4649 10823 4641 10823 4635 10826 4631 10825
      4627 10829 4627 10831 4627 10833 4626 10833

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...0.5-1 INCH IN 1 HOUR

$$

Palmquist
2 follow-up statements
926 
WGUS75 KBYZ 052331
FFSBYZ

Flash Flood Statement
National Weather Service Billings MT
531 PM MDT Sat Jun 5 2021

MTC065-060100-
/O.CON.KBYZ.FF.W.0001.000000T0000Z-210606T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Musselshell MT-
531 PM MDT Sat Jun 5 2021

...FLASH FLOOD WARNING FOR THE BOBCAT BURN AREA REMAINS IN EFFECT 
UNTIL 7 PM MDT THIS EVENING FOR CENTRAL MUSSELSHELL COUNTY...

At 531 PM MDT, Thunderstorms have produced heavy rain over the 
BobCat Burn Area. Radar estimates of up to an inch of rain has 
fallen in a short amount of time. Flash flooding is possible.

Excessive rainfall over the burn scar may result in debris flow 
moving through the Halfbreed Creek, East Parrot Creek, Parrot Creek, 
West Parrot Creek, Musselshell River, Cow Gulch, Railroad Creek, 
Fattig Creek, and Rehder Coulee.

Roads that may be impacted include Highway 87, Beard Road, West 
Parrot Creek Road, East Parrot Creek Road, Fattig Creek Road, Rehder 
Road. The debris flow can consist of rock, mud, vegetation and other 
loose materials.

HAZARD...Flash flooding caused by thunderstorms in and around the
         BobCat Burn Area.

SOURCE...Radar.

IMPACT...Flooding of areas in and downstream of the BobCat Burn
         Area.

Some locations that may experience flash flooding include...
  Klein.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain alert for flooding of creeks, streams, and normally dry 
coulees even in areas not receiving rainfall downstream of the burn 
area.

Please report observed flooding to local emergency officials and 
request they pass the information to the National Weather Service in 
Billings.

&&

LAT...LON 4627 10839 4626 10844 4631 10849 4635 10850
      4638 10855 4643 10857 4643 10855 4644 10851
      4646 10846 4647 10835 4650 10828 4651 10824
      4649 10823 4641 10823 4635 10826 4631 10825
      4627 10829 4627 10831 4627 10833 4626 10833

FLASH FLOOD...RADAR INDICATED

$$

Palmquist
302 
WGUS75 KBYZ 060102
FFSBYZ

Flash Flood Statement
National Weather Service Billings MT
702 PM MDT Sat Jun 5 2021

MTC065-060112-
/O.EXP.KBYZ.FF.W.0001.000000T0000Z-210606T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Musselshell MT-
702 PM MDT Sat Jun 5 2021

...FLASH FLOOD WARNING FOR THE BOBCAT BURN AREA HAS EXPIRED FOR 
CENTRAL MUSSELSHELL COUNTY...

Flooding and debris flow is no longer expected to pose a threat. 
Please continue to use caution and remain alert, especially 
overnight, for debris and water on roadways.

LAT...LON 4627 10839 4626 10844 4631 10849 4635 10850
      4638 10855 4643 10857 4643 10855 4644 10851
      4646 10846 4647 10835 4650 10828 4651 10824
      4649 10823 4641 10823 4635 10826 4631 10825
      4627 10829 4627 10831 4627 10833 4626 10833

$$

Tesar

The office that day

Everything else NWS Billings, MT issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 4, 9:00 PM MDTSpecial Weather StatementBYZSweet Grass30 min
Jun 4, 9:19 PM MDTSpecial Weather StatementBYZWheatland26 min
Jun 4, 9:51 PM MDTSpecial Weather StatementBYZPark39 min
Jun 4, 10:28 PM MDTSpecial Weather StatementBYZSweet Grass32 min
Jun 4, 11:24 PM MDTSpecial Weather StatementBYZWheatland36 min
Jun 4, 11:41 PM MDTSevere Thunderstorm WarningBYZWheatland34 min
Jun 5, 2:26 PM MDTSpecial Weather StatementBYZSweet Grass34 min
Jun 5, 3:50 PM MDTSpecial Weather StatementBYZMusselshell40 min
Jun 5, 4:14 PM MDTSpecial Weather StatementBYZYellowstone31 min
Jun 5, 4:44 PM MDTSevere Thunderstorm WarningBYZYellowstone31 min

Nearby

Flash Flood Warnings in Montana, 2021Every flash flood warning in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.