Alert archive / Colorado / Tornado Watches in 2018
Tornado Watch 315
The Storm Prediction Center issued this tornado watch at Jul 27, 2018, 1:04 PM MDT for 4 states. It was in force for 8 hr.
The area
The outline as issued.
The facts
- Issued
- Jul 27, 2018, 1:04 PM MDT (19:04 UTC)
- Expired
- Jul 27, 2018, 9:00 PM MDT
- In force
- 8 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2.5 in
- Strongest gust expected
- 70 kt
All 45 counties
Adams County, CO, Arapahoe County, CO, Cheyenne County, CO, Elbert County, CO, Kit Carson County, CO, Larimer 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, Decatur County, KS, Gove County, KS, Graham County, KS, Greeley County, KS, Logan County, KS, Norton County, KS, Rawlins County, KS, Sheridan County, KS, Sherman County, KS, Thomas County, KS, Wallace County, KS, Wichita County, KS, Banner County, NE, Chase County, NE, Cheyenne County, NE, Deuel County, NE, Dundy County, NE, Hayes County, NE, Hitchcock County, NE, Kimball County, NE, Morrill County, NE, Perkins County, NE, Red Willow County, NE, Scotts Bluff County, NE, Albany County, WY, Converse County, WY, Goshen County, WY, Laramie County, WY, Niobrara County, WY, Platte County, WY
The radar
The Cheyenne radar (KCYS), 118 km from the middle of the area, began a volume at 19:06 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
- 60%
- One or more EF2 to EF5 tornadoes
- 20%
- Ten or more severe wind reports
- 70%
- One or more gusts of 65 knots or more
- 70%
- Ten or more severe hail reports
- 70%
- One or more hailstones of 2 inches or more
- 70%
- Six or more combined severe hail and wind reports
- 95%
Warnings issued inside it
47 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 27, 1:08 PM MDT | Severe Thunderstorm Warning | CYS | Cheyenne | 25 min |
| Jul 27, 1:53 PM MDT | Severe Thunderstorm Warning | BOU | Phillips, Sedgwick | 52 min |
| Jul 27, 2:24 PM MDT | Severe Thunderstorm Warning | CYS | Albany, Laramie | 51 min |
| Jul 27, 2:33 PM MDT | Severe Thunderstorm Warning | GLD | Yuma | 42 min |
| Jul 27, 2:38 PM MDT | Severe Thunderstorm Warning | GLD | Dundy, Hitchcock | 21 min |
| Jul 27, 2:56 PM MDT | Severe Thunderstorm Warning | GLD | Graham | 30 min |
| Jul 27, 2:58 PM MDT | Severe Thunderstorm Warning | GLD | Yuma | 47 min |
| Jul 27, 2:58 PM MDT | Severe Thunderstorm Warning | CYS | Laramie | 24 min |
| Jul 27, 3:08 PM MDT | Severe Thunderstorm Warning | BOU | Elbert | 37 min |
| Jul 27, 3:23 PM MDT | Severe Thunderstorm Warning | GLD | Yuma | 52 min |
| Jul 27, 3:26 PM MDT | Tornado Warning | BOU | Morgan, Weld | 34 min |
| Jul 27, 3:43 PM MDT | Tornado Warning | BOU | Washington | 32 min |
| Jul 27, 3:45 PM MDT | Severe Thunderstorm Warning | BOU | Adams, Morgan, Weld | 25 min |
| Jul 27, 3:47 PM MDT | Severe Thunderstorm Warning | BOU | Arapahoe, Elbert | 43 min |
| Jul 27, 3:47 PM MDT | Severe Thunderstorm Warning | GLD | Yuma | 58 min |
| Jul 27, 3:50 PM MDT | Severe Thunderstorm Warning | GLD | Kit Carson | 40 min |
| Jul 27, 3:59 PM MDT | Tornado Warning | GLD | Kit Carson | 13 min |
| Jul 27, 4:08 PM MDT | Severe Thunderstorm Warning | BOU | Arapahoe, Elbert, Lincoln, Washington | 41 min |
| Jul 27, 4:10 PM MDT | Tornado Warning | BOU | Adams, Arapahoe | 35 min |
| Jul 27, 4:25 PM MDT | Severe Thunderstorm Warning | GLD | Cheyenne, Sherman | 65 min |
| Jul 27, 4:28 PM MDT | Tornado Warning | BOU | Arapahoe | 32 min |
| Jul 27, 4:28 PM MDT | Severe Thunderstorm Warning | GLD | Kit Carson | 62 min |
| Jul 27, 4:35 PM MDT | Tornado Warning | BOU | Washington | 25 min |
| Jul 27, 4:37 PM MDT | Tornado Warning | GLD | Kit Carson | 25 min |
| Jul 27, 4:57 PM MDT | Tornado Warning | BOU | Lincoln | 19 min |
| Jul 27, 4:57 PM MDT | Severe Thunderstorm Warning | CYS | Albany, Laramie | 33 min |
| Jul 27, 5:16 PM MDT | Severe Thunderstorm Warning | GLD | Logan, Sherman, Wallace | 44 min |
| Jul 27, 5:21 PM MDT | Severe Thunderstorm Warning | GLD | Cheyenne, Kit Carson, Yuma | 54 min |
| Jul 27, 5:21 PM MDT | Severe Thunderstorm Warning | CYS | Converse | 39 min |
| Jul 27, 5:29 PM MDT | Severe Thunderstorm Warning | CYS | Laramie | 46 min |
| Jul 27, 5:31 PM MDT | Severe Thunderstorm Warning | GLD | Sherman | 29 min |
| Jul 27, 5:34 PM MDT | Flash Flood Warning | GLD | Kit Carson, Yuma | 3 hr |
| Jul 27, 5:43 PM MDT | Severe Thunderstorm Warning | CYS | Converse | 32 min |
| Jul 27, 5:56 PM MDT | Severe Thunderstorm Warning | BOU | Larimer, Weld | 34 min |
| Jul 27, 5:58 PM MDT | Severe Thunderstorm Warning | GLD | Logan, Sherman, Wallace | 47 min |
| Jul 27, 6:03 PM MDT | Severe Thunderstorm Warning | GLD | Cheyenne, Kit Carson, Yuma | 57 min |
| Jul 27, 6:08 PM MDT | Severe Thunderstorm Warning | CYS | Albany, Converse, Platte | 52 min |
| Jul 27, 6:25 PM MDT | Severe Thunderstorm Warning | BOU | Lincoln | 50 min |
| Jul 27, 6:26 PM MDT | Severe Thunderstorm Warning | GLD | Logan, Wallace | 34 min |
| Jul 27, 6:57 PM MDT | Severe Thunderstorm Warning | GLD | Cheyenne | 10 min |
| Jul 27, 6:58 PM MDT | Severe Thunderstorm Warning | GLD | Greeley, Logan, Wallace, Wichita | 47 min |
| Jul 27, 7:09 PM MDT | Severe Thunderstorm Warning | CYS | Albany, Platte | 29 min |
| Jul 27, 7:34 PM MDT | Severe Thunderstorm Warning | GLD | Greeley, Wichita | 56 min |
| Jul 27, 7:54 PM MDT | Tornado Warning | GLD | Greeley, Wichita | 19 min |
| Jul 27, 7:56 PM MDT | Tornado Warning | GLD | Wichita | 23 min |
| Jul 27, 8:01 PM MDT | Severe Thunderstorm Warning | CYS | Converse | 29 min |
| Jul 27, 8:25 PM MDT | Severe Thunderstorm Warning | CYS | Converse | 50 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 (KDEN), launched 12:00Z, 7.1 hours before the alert went out and 113 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
- 735 J/kg
- Mixed-layer CIN
- -87 J/kg
- Mixed-layer LCL
- 574 m above ground
- 0-6 km bulk shear
- 27 kt
- 0-1 km storm-relative helicity
- 13 m²/s²
- 0-3 km storm-relative helicity
- 91 m²/s²
- Significant tornado parameter
- 0.1
- Supercell composite
- 1.1
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 26, 6:07 PM MDT | Mesoscale Discussion | SPC | Adams, Arapahoe, Boulder, Broomfield, Cheyenne, Crowley and 18 more | 113 min |
| Jul 26, 8:53 PM MDT | Mesoscale Discussion | SPC | Prowers | 2 hr |
| Jul 27, 12:35 PM MDT | Mesoscale Discussion | SPC | Adams, Kit Carson, Logan, Morgan, Phillips, Sedgwick and 3 more | 85 min |
| Jul 27, 2:52 PM MDT | Mesoscale Discussion | SPC | Bent, Cheyenne, Crowley, Elbert, El Paso, Huerfano and 8 more | 83 min |
| Jul 27, 3:43 PM MDT | Severe Thunderstorm Watch | SPC | Baca, Bent, Crowley, El Paso, Huerfano, Kiowa and 4 more | 5 hr |
| Jul 27, 5:23 PM MDT | Mesoscale Discussion | SPC | Cheyenne | 97 min |
| Jul 27, 4:05 PM MDT | Severe Thunderstorm Watch | SPC | Barber, Barton, Clark, Comanche, Edwards, Ellis and 25 more | 9 hr |
| Jul 27, 4:55 PM MDT | Mesoscale Discussion | SPC | Blaine, Brown, Cherry, Custer, Dawes, Dawson and 11 more | 2 hr |
Nearby
Tornado Watches in Colorado, 2018Tornado Watches in Kansas, 2018Tornado Watches in Nebraska, 2018Every tornado watch in 2018
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.