Alert archive / Montana / Severe Thunderstorm Warnings in 2015

Severe Thunderstorm Warning 55, NWS Billings, MT

June 21, 2015Carter County, Custer County, Fallon County, Montana

NWS Billings, MT issued this severe thunderstorm warning at Jun 21, 2015, 8:22 PM MDT for Carter County, Custer County, Fallon County, Montana. It was in force for 53 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Jun 21, 2015, 8:22 PM MDT (02:22 UTC)
Expired
Jun 21, 2015, 9:15 PM MDT
In force
53 min
Issued by
NWS Billings, MT
Area
Storm-based polygon
Hail
1.75 in
Wind
70.0 mph

Counties Carter County, MT, Custer County, MT, Fallon County, MT

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Jun 21, 2:23 PM MDTTornado WatchSPC8 hr

The nearest sounding before it

Rapid City, SD (KRAP), launched 00:00Z, 2.4 hours before the alert went out and 267 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, Rapid City, SD at 00:00Z on 2015-06-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1709 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Rapid City, SD at 00:00Z on 2015-06-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 189 square meters per square second.1939587897Sfc1 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
1709 J/kg
Mixed-layer CIN
-112 J/kg
Mixed-layer LCL
1661 m above ground
0-6 km bulk shear
59 kt
0-1 km storm-relative helicity
189 m²/s²
0-3 km storm-relative helicity
236 m²/s²
Significant tornado parameter
0.5
Supercell composite
12.2

Open this sounding in Storm Lab

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 21, 7:15 PM MDTSpecial Weather StatementBYZRosebud60 min
Jun 21, 7:36 PM MDTSevere Thunderstorm WarningBYZCuster, Rosebud54 min
Jun 21, 7:37 PM MDTSpecial Weather StatementBYZYellowstone53 min
Jun 21, 7:51 PM MDTSpecial Weather StatementBYZTreasure24 min
Jun 21, 8:19 PM MDTSpecial Weather StatementBYZRosebud41 min
Jun 21, 8:21 PM MDTSpecial Weather StatementBYZTreasure39 min
Jun 21, 9:13 PM MDTSevere Thunderstorm WarningBYZCarter, Fallon62 min
Jun 21, 10:11 PM MDTSpecial Weather StatementBYZCarter64 min
Jun 21, 10:36 PM MDTSevere Thunderstorm WarningBYZCarter20 min
Jun 21, 8:57 PM MDTSpecial Weather StatementBYZSheridan63 min

Nearby

Severe Thunderstorm Warnings in Montana, 2015Every severe thunderstorm warning in 2015

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.