Alert archive / Colorado / Severe Thunderstorm Watches in 2006
Severe Thunderstorm Watch 628
The Storm Prediction Center issued this severe thunderstorm watch at Jul 20, 2006, 3:47 PM MDT for 4 states. It was in force for 7 hr.
The area
The outline as issued.
The facts
- Issued
- Jul 20, 2006, 3:47 PM MDT (21:47 UTC)
- Expired
- Jul 20, 2006, 11:00 PM MDT
- In force
- 7 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 60 kt
All 33 counties
Cheyenne 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, KS, Greeley County, KS, Logan County, KS, Rawlins County, KS, Sherman County, KS, Thomas County, KS, Wallace County, KS, Wichita County, KS, Banner County, NE, Box Butte County, NE, Cheyenne County, NE, Dawes County, NE, Dundy County, NE, Hitchcock County, NE, Kimball County, NE, Morrill County, NE, Scotts Bluff County, NE, Sioux County, NE, Converse County, WY, Goshen County, WY, Laramie County, WY, Niobrara County, WY, Platte County, WY
The radar
The Cheyenne radar (KCYS), 61 km from the middle of the area, began a volume at 21:47 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.
What SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 20%
- One or more EF2 to EF5 tornadoes
- 10%
- Ten or more severe wind reports
- 60%
- One or more gusts of 65 knots or more
- 30%
- Ten or more severe hail reports
- 60%
- One or more hailstones of 2 inches or more
- 20%
- Six or more combined severe hail and wind reports
- 80%
Warnings issued inside it
13 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 20, 3:51 PM MDT | Severe Thunderstorm Warning | CYS | Platte | 54 min |
| Jul 20, 4:05 PM MDT | Severe Thunderstorm Warning | CYS | Goshen, Laramie | 55 min |
| Jul 20, 4:45 PM MDT | Severe Thunderstorm Warning | CYS | Laramie, Platte | 32 min |
| Jul 20, 5:01 PM MDT | Severe Thunderstorm Warning | CYS | Goshen | 44 min |
| Jul 20, 5:39 PM MDT | Severe Thunderstorm Warning | GLD | Kit Carson | 66 min |
| Jul 20, 6:11 PM MDT | Severe Thunderstorm Warning | BOU | Washington | 49 min |
| Jul 20, 6:16 PM MDT | Severe Thunderstorm Warning | BOU | Lincoln | 32 min |
| Jul 20, 6:22 PM MDT | Severe Thunderstorm Warning | CYS | Laramie | 53 min |
| Jul 20, 6:45 PM MDT | Severe Thunderstorm Warning | GLD | Kit Carson | 60 min |
| Jul 20, 6:55 PM MDT | Severe Thunderstorm Warning | BOU | Washington | 35 min |
| Jul 20, 6:55 PM MDT | Severe Thunderstorm Warning | CYS | Kimball | 27 min |
| Jul 20, 7:08 PM MDT | Flash Flood Warning | BOU | Washington | 3 hr |
| Jul 20, 7:28 PM MDT | Severe Thunderstorm Warning | BOU | Washington | 35 min |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Denver, CO (KDNR), launched 12:00Z, 9.8 hours before the alert went out and 179 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.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 2332 m above ground
- 0-6 km bulk shear
- 6 kt
- 0-1 km storm-relative helicity
- -5 m²/s²
- 0-3 km storm-relative helicity
- 9 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 20, 2:30 PM MDT | Mesoscale Discussion | SPC | Adams, Arapahoe, Broomfield, Denver, Douglas, Elbert and 5 more | 2 hr |
| Jul 19, 6:57 PM MDT | Mesoscale Discussion | SPC | Dakota, Dixon | 93 min |
| Jul 20, 4:32 PM MDT | Mesoscale Discussion | SPC | Crook, Weston | 118 min |
Nearby
Severe Thunderstorm Watches in Colorado, 2006Severe Thunderstorm Watches in Nebraska, 2006Severe Thunderstorm Watches in Kansas, 2006Every severe thunderstorm watch in 2006
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.