Alert archive / Montana / Mesoscale Discussions in 2016

Mesoscale Discussion 1616

September 1, 201621 counties in Montana; Campbell County, Crook County, Sheridan County, Wyoming

The Storm Prediction Center issued this mesoscale discussion at Sep 1, 2016, 6:33 PM MDT for 21 counties in Montana; Campbell County, Crook County, Sheridan County, Wyoming. It was in force for 117 min.

The area

The outline as issued.

The facts

Issued
Sep 1, 2016, 6:33 PM MDT (00:33 UTC)
Expired
Sep 1, 2016, 8:30 PM MDT
In force
117 min
Issued by
the Storm Prediction Center
Chance of a watch
5%
All 24 counties

Big Horn County, MT, Blaine County, MT, Carbon County, MT, Chouteau County, MT, Custer County, MT, Fergus County, MT, Garfield County, MT, Golden Valley County, MT, Hill County, MT, Judith Basin County, MT, Liberty County, MT, Musselshell County, MT, Petroleum County, MT, Phillips County, MT, Powder River County, MT, Rosebud County, MT, Stillwater County, MT, Sweet Grass County, MT, Treasure County, MT, Wheatland County, MT, Yellowstone County, MT, Campbell County, WY, Crook County, WY, Sheridan County, WY

The radar

The Billings radar (KBLX), 99 km from the middle of the area, began a volume at 00:36 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

Glasgow Intl Airport, MT (KGGW), launched 00:00Z, 0.6 hours before the alert went out and 205 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, Glasgow Intl Airport, MT at 00:00Z on 2016-09-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 860 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, Glasgow Intl Airport, MT at 00:00Z on 2016-09-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -21 square meters per square second.193958Sfc1 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
860 J/kg
Mixed-layer CIN
-139 J/kg
Mixed-layer LCL
2855 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
-21 m²/s²
0-3 km storm-relative helicity
27 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.2

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 2, 4:16 PM MDTMesoscale DiscussionSPCCarter, Fallon, Richland, Sheridan, Wibaux2 hr

Nearby

Mesoscale Discussions in Montana, 2016Mesoscale Discussions in Wyoming, 2016Every mesoscale discussion in 2016

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.