Alert archive / Colorado / Mesoscale Discussions in 2017

Mesoscale Discussion 1368

July 20, 201714 counties in Colorado; Cheyenne County, Kimball County, Nebraska; Laramie County, Wyoming

The Storm Prediction Center issued this mesoscale discussion at Jul 20, 2017, 2:35 PM MDT for 14 counties in Colorado; Cheyenne County, Kimball County, Nebraska; Laramie County, Wyoming. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Jul 20, 2017, 2:35 PM MDT (20:35 UTC)
Expired
Jul 20, 2017, 5:00 PM MDT
In force
2 hr
Issued by
the Storm Prediction Center
Chance of a watch
20%

Counties Adams County, CO, Arapahoe County, CO, Broomfield County, CO, Denver County, CO, Elbert County, CO, Kit Carson County, CO, Lincoln County, CO, Logan County, CO, Morgan County, CO, Phillips County, CO, Sedgwick County, CO, Washington County, CO, Weld County, CO, Yuma County, CO, Cheyenne County, NE, Kimball County, NE, Laramie County, WY

The nearest sounding before it

Denver, CO (KDEN), launched 12:00Z, 8.6 hours before the alert went out and 58 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, Denver, CO at 12:00Z on 2017-07-20Temperature 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, Denver, CO at 12:00Z on 2017-07-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -44 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
1665 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
-44 m²/s²
0-3 km storm-relative helicity
2 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

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
Jul 19, 6:06 PM MDTMesoscale DiscussionSPCAntelope, Boyd, Brown, Cedar, Cherry, Dakota and 7 more84 min
Jul 20, 2:18 PM MDTMesoscale DiscussionSPCBig Horn, Fremont, Hot Springs, Park, Sublette, Teton and 1 more2 hr

Nearby

Mesoscale Discussions in Colorado, 2017Mesoscale Discussions in Nebraska, 2017Mesoscale Discussions in Wyoming, 2017Every mesoscale discussion in 2017

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.