Alert archive / Montana / Mesoscale Discussions in 2011

Mesoscale Discussion 1526

July 6, 201115 counties in Montana; 5 counties in Wyoming

The Storm Prediction Center issued this mesoscale discussion at Jul 6, 2011, 2:19 PM MDT for 15 counties in Montana; 5 counties in Wyoming. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Jul 6, 2011, 2:19 PM MDT (20:19 UTC)
Expired
Jul 6, 2011, 4:45 PM MDT
In force
2 hr
Issued by
the Storm Prediction Center

Counties Big Horn County, MT, Broadwater County, MT, Carbon County, MT, Carter County, MT, Custer County, MT, Gallatin County, MT, Judith Basin County, MT, Meagher County, MT, Park County, MT, Powder River County, MT, Rosebud County, MT, Stillwater County, MT, Sweet Grass County, MT, Wheatland County, MT, Yellowstone County, MT, Big Horn County, WY, Campbell County, WY, Crook County, WY, Johnson County, WY, Sheridan County, WY

The nearest sounding before it

Great_falls, MT (KTFX), launched 12:00Z, 8.3 hours before the alert went out and 223 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 2011-07-06Temperature 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°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Great_falls, MT at 12:00Z on 2011-07-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -74 square meters per square second.1939Sfc1 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
2290 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
-74 m²/s²
0-3 km storm-relative helicity
85 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 6, 2:38 PM MDTMesoscale DiscussionSPCLaramie67 min

Nearby

Mesoscale Discussions in Montana, 2011Mesoscale Discussions in Wyoming, 2011Every mesoscale discussion in 2011

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.