Alert archive / Colorado / Severe Thunderstorm Watches in 2002

Severe Thunderstorm Watch 647

August 27, 200212 counties in Colorado; Albany County, Laramie County, Platte County, Wyoming

The Storm Prediction Center issued this severe thunderstorm watch at Aug 27, 2002, 2:40 PM MDT for 12 counties in Colorado; Albany County, Laramie County, Platte County, Wyoming. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Aug 27, 2002, 2:40 PM MDT (20:40 UTC)
Expired
Aug 27, 2002, 8:00 PM MDT
In force
5 hr
Issued by
the Storm Prediction Center

Counties Adams County, CO, Arapahoe County, CO, Boulder County, CO, Broomfield County, CO, Denver County, CO, Douglas County, CO, Elbert County, CO, Gilpin County, CO, Jefferson County, CO, Larimer County, CO, Morgan County, CO, Weld County, CO, Albany County, WY, Laramie County, WY, Platte County, WY

The radar

The Cheyenne radar (KCYS), 8 km from the middle of the area, began a volume at 20:44 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.

Warnings issued inside it

5 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Aug 27, 2:52 PM MDTTornado WarningBOUJefferson38 min
Aug 27, 3:18 PM MDTTornado WarningBOUArapahoe, Denver, Douglas, Jefferson42 min
Aug 27, 6:26 PM MDTSevere Thunderstorm WarningBOUDouglas, Jefferson49 min
Aug 27, 7:05 PM MDTSevere Thunderstorm WarningCYSAlbany40 min
Aug 27, 7:41 PM MDTTornado WarningCYSAlbany34 min

The nearest sounding before it

Riverton, WY (KRIW), launched 12:00Z, 8.7 hours before the alert went out and 367 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, Riverton, WY at 12:00Z on 2002-08-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 18 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Riverton, WY at 12:00Z on 2002-08-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 63 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
18 J/kg
Mixed-layer CIN
-182 J/kg
Mixed-layer LCL
1237 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
63 m²/s²
0-3 km storm-relative helicity
83 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

Nearby

Severe Thunderstorm Watches in Colorado, 2002Severe Thunderstorm Watches in Wyoming, 2002Every severe thunderstorm watch in 2002

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.