Alert archive / Colorado / Mesoscale Discussions in 2004

Mesoscale Discussion 1961

August 11, 200420 counties in Colorado

The Storm Prediction Center issued this mesoscale discussion at Aug 11, 2004, 12:11 PM MDT for 20 counties in Colorado. It was in force for 94 min.

The area

The outline as issued.

The facts

Issued: Aug 11, 2004, 12:11 PM MDT (18:11 UTC)
Expired: Aug 11, 2004, 1:45 PM MDT
In force: 94 min
Issued by: the Storm Prediction Center

Counties Adams County, CO, Arapahoe County, CO, Boulder County, CO, Broomfield County, CO, Clear Creek County, CO, Crowley County, CO, Denver County, CO, Douglas County, CO, El Paso County, CO, Elbert County, CO, Gilpin County, CO, Jefferson County, CO, Larimer County, CO, Lincoln County, CO, Morgan County, CO, Park County, CO, Pueblo County, CO, Teller County, CO, Washington County, CO, Weld County, CO

The radar

The Denver radar (KFTG), 28 km from the middle of the area, began a volume at 18:09 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.

Severe Thunderstorm Watch 740Aug 11, 1:20 PM MDT

The nearest sounding before it

Grand Junction, CO (KGJT), launched 12:00Z, 6.2 hours before the alert went out and 357 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 3620 m above ground
0-6 km bulk shear: 36 kt
0-1 km storm-relative helicity: -4 m²/s²
0-3 km storm-relative helicity: 46 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

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
Aug 10, 6:46 PM MDT	Mesoscale Discussion	SPC	Adams, Arapahoe, Broomfield, Crowley, Denver, Douglas and 6 more	59 min
Aug 10, 8:35 PM MDT	Tornado Watch	SPC	Baca, Bent, Crowley, Huerfano, Kiowa, Las Animas and 3 more	4 hr
Aug 11, 1:20 PM MDT	Severe Thunderstorm Watch	SPC	Adams, Arapahoe, Boulder, Broomfield, Crowley, Denver and 13 more	7 hr
Aug 11, 5:27 PM MDT	Mesoscale Discussion	SPC	Crowley, Denver, Douglas, Elbert, El Paso, Huerfano and 6 more	2 hr

Nearby

Mesoscale Discussions in Colorado, 2004 Every mesoscale discussion in 2004

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.