Alert archive / Colorado / Mesoscale Discussions in 2007

Mesoscale Discussion 551

April 23, 200716 counties in Colorado

The Storm Prediction Center issued this mesoscale discussion at Apr 23, 2007, 6:52 PM MDT for 16 counties in Colorado. It was in force for 113 min.

The area

The outline as issued.

The facts

Issued: Apr 23, 2007, 6:52 PM MDT (00:52 UTC)
Expired: Apr 23, 2007, 8:45 PM MDT
In force: 113 min
Issued by: the Storm Prediction Center

Counties Adams County, CO, Arapahoe County, CO, Bent County, CO, Cheyenne County, CO, Crowley County, CO, El Paso County, CO, Elbert County, CO, Kiowa County, CO, Kit Carson County, CO, Lincoln County, CO, Logan County, CO, Morgan County, CO, Phillips County, CO, Prowers County, CO, Washington County, CO, Yuma County, CO

The radar

The Denver radar (KFTG), 100 km from the middle of the area, began a volume at 00:52 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

Tornado Watch 171Apr 23, 9:40 PM MDT

The nearest sounding before it

Denver, CO (KDNR), launched 00:00Z, 0.9 hours before the alert went out and 68 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 351 J/kg
Mixed-layer CIN: -75 J/kg
Mixed-layer LCL: 1440 m above ground
0-6 km bulk shear: 56 kt
0-1 km storm-relative helicity: 187 m²/s²
0-3 km storm-relative helicity: 380 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 4.5

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.

Issued	Product	Office	Counties	Lasted
Apr 23, 9:41 PM MDT	Tornado Watch	SPC	Kit Carson, Yuma	5 hr
Apr 24, 12:37 AM MDT	Mesoscale Discussion	SPC	Cheyenne, Kit Carson, Phillips, Yuma	83 min
Apr 24, 1:48 PM MDT	Mesoscale Discussion	SPC	Cheyenne, Kit Carson, Lincoln, Yuma	117 min

Nearby

Mesoscale Discussions in Colorado, 2007 Every mesoscale discussion in 2007

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.