Alert archive / Colorado / Tornado Watches in 1999

Tornado Watch 666

September 3, 199911 counties in Colorado; 11 counties in Nebraska; Goshen County, Laramie County, Wyoming

The Storm Prediction Center issued this tornado watch at Sep 3, 1999, 4:15 PM MDT for 11 counties in Colorado; 11 counties in Nebraska; Goshen County, Laramie County, Wyoming. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Sep 3, 1999, 4:15 PM MDT (22:15 UTC)
Expired
Sep 3, 1999, 10:00 PM MDT
In force
6 hr
Issued by
the Storm Prediction Center
All 24 counties

Adams County, CO, Arapahoe County, CO, Elbert County, CO, Kit Carson County, CO, Logan County, CO, Morgan County, CO, Phillips County, CO, Sedgwick County, CO, Washington County, CO, Weld County, CO, Yuma County, CO, Banner County, NE, Box Butte County, NE, Cheyenne County, NE, Dawes County, NE, Deuel County, NE, Garden County, NE, Kimball County, NE, Morrill County, NE, Scotts Bluff County, NE, Sheridan County, NE, Sioux County, NE, Goshen County, WY, Laramie County, WY

The radar

The Cheyenne radar (KCYS), 142 km from the middle of the area, began a volume at 22:14 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

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

IssuedProductOfficeCountiesLasted
Sep 3, 4:29 PM MDTSevere Thunderstorm WarningBOUAdams, Denver, Weld41 min
Sep 3, 4:51 PM MDTSevere Thunderstorm WarningCYSLaramie34 min
Sep 3, 5:02 PM MDTSevere Thunderstorm WarningBOUAdams, Denver, Jefferson43 min
Sep 3, 5:13 PM MDTSevere Thunderstorm WarningBOUMorgan, Weld32 min
Sep 3, 5:25 PM MDTSevere Thunderstorm WarningBOUWeld35 min
Sep 3, 5:29 PM MDTSevere Thunderstorm WarningCYSGoshen, Laramie61 min
Sep 3, 5:45 PM MDTSevere Thunderstorm WarningBOUAdams, Denver45 min
Sep 3, 5:45 PM MDTSevere Thunderstorm WarningBOUWeld45 min
Sep 3, 5:51 PM MDTSevere Thunderstorm WarningBOUMorgan39 min
Sep 3, 6:14 PM MDTSevere Thunderstorm WarningCYSBanner, Scotts Bluff, Sioux61 min
Sep 3, 6:14 PM MDTSevere Thunderstorm WarningCYSKimball61 min
Sep 3, 6:28 PM MDTTornado WarningBOUMorgan32 min
Sep 3, 6:29 PM MDTSevere Thunderstorm WarningCYSLaramie31 min
Sep 3, 6:32 PM MDTSevere Thunderstorm WarningBOUAdams, Weld43 min
Sep 3, 6:35 PM MDTTornado WarningCYSScotts Bluff, Sioux35 min
Sep 3, 7:02 PM MDTTornado WarningBOULogan, Morgan, Washington28 min
Sep 3, 7:08 PM MDTSevere Thunderstorm WarningBOUMorgan, Weld52 min
Sep 3, 7:21 PM MDTSevere Thunderstorm WarningCYSBanner, Morrill34 min
Sep 3, 7:33 PM MDTTornado WarningBOULogan, Washington42 min
Sep 3, 8:00 PM MDTSevere Thunderstorm WarningBOUMorgan, Weld45 min
Sep 3, 8:15 PM MDTTornado WarningBOULogan, Phillips, Sedgwick30 min
Sep 3, 8:23 PM MDTSevere Thunderstorm WarningGLDYuma62 min
Sep 3, 8:48 PM MDTTornado WarningBOUPhillips, Sedgwick27 min
Sep 3, 9:15 PM MDTSevere Thunderstorm WarningBOUPhillips, Sedgwick45 min

The nearest sounding before it

Denver, CO (KDNR), launched 12:00Z, 10.3 hours before the alert went out and 169 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 1999-09-03Temperature 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 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 1999-09-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -18 square meters per square second.19395878Sfc1 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
1331 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
-18 m²/s²
0-3 km storm-relative helicity
36 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

Nearby

Tornado Watches in Colorado, 1999Tornado Watches in Nebraska, 1999Tornado Watches in Wyoming, 1999Every tornado watch in 1999

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.