Alert archive / Colorado / Tornado Watches in 2014
Tornado Watch 165
The Storm Prediction Center issued this tornado watch at May 21, 2014, 12:34 PM MDT for 11 counties in Colorado; Goshen County, Laramie County, Platte County, Wyoming. It was in force for 8 hr.
The area
The outline as issued.
The facts
- Issued
- May 21, 2014, 12:34 PM MDT (18:34 UTC)
- Expired
- May 21, 2014, 8:25 PM MDT
- In force
- 8 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 3 in
- Strongest gust expected
- 60 kt
Counties Adams County, CO, Arapahoe County, CO, Boulder County, CO, Broomfield County, CO, Denver County, CO, Douglas County, CO, Elbert County, CO, Jefferson County, CO, Larimer County, CO, Morgan County, CO, Weld County, CO, Goshen County, WY, Laramie County, WY, Platte County, WY
The radar
The Cheyenne radar (KCYS), 6 km from the middle of the area, began a volume at 18:37 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
- 30%
- Ten or more severe wind reports
- 40%
- One or more gusts of 65 knots or more
- 10%
- Ten or more severe hail reports
- 80%
- One or more hailstones of 2 inches or more
- 50%
- Six or more combined severe hail and wind reports
- 90%
Warnings issued inside it
16 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 21, 1:00 PM MDT | Severe Thunderstorm Warning | BOU | Jefferson | 45 min |
| May 21, 1:36 PM MDT | Severe Thunderstorm Warning | BOU | Adams, Arapahoe, Denver | 39 min |
| May 21, 1:56 PM MDT | Tornado Warning | BOU | Adams, Arapahoe, Denver | 34 min |
| May 21, 2:21 PM MDT | Severe Thunderstorm Warning | BOU | Adams, Denver | 39 min |
| May 21, 2:23 PM MDT | Tornado Warning | BOU | Adams, Arapahoe, Denver | 22 min |
| May 21, 2:42 PM MDT | Tornado Warning | BOU | Adams, Arapahoe | 33 min |
| May 21, 3:18 PM MDT | Tornado Warning | BOU | Adams, Arapahoe, Denver | 27 min |
| May 21, 3:47 PM MDT | Severe Thunderstorm Warning | BOU | Adams, Arapahoe | 28 min |
| May 21, 3:57 PM MDT | Severe Thunderstorm Warning | BOU | Douglas, Elbert | 48 min |
| May 21, 4:18 PM MDT | Severe Thunderstorm Warning | BOU | Adams, Arapahoe | 42 min |
| May 21, 4:57 PM MDT | Tornado Warning | BOU | Adams | 48 min |
| May 21, 5:34 PM MDT | Severe Thunderstorm Warning | BOU | Adams, Morgan, Washington | 41 min |
| May 21, 5:38 PM MDT | Flash Flood Warning | CYS | Platte | 6 hr |
| May 21, 6:58 PM MDT | Tornado Warning | CYS | Platte | 32 min |
| May 21, 7:48 PM MDT | Tornado Warning | CYS | Platte | 27 min |
| May 21, 8:04 PM MDT | Flash Flood Warning | CYS | Platte | 4 hr |
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, 6.6 hours before the alert went out and 199 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
- 268 J/kg
- Mixed-layer CIN
- -75 J/kg
- Mixed-layer LCL
- 786 m above ground
- 0-6 km bulk shear
- 36 kt
- 0-1 km storm-relative helicity
- 86 m²/s²
- 0-3 km storm-relative helicity
- 158 m²/s²
- Significant tornado parameter
- 0.1
- Supercell composite
- 2.3
The text
As transmitted, in the capitals the NWS used until 2016.
038
WWUS20 KWNS 211833
SEL5
SPC WW 211833
COZ000-WYZ000-220200-
URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 165
NWS STORM PREDICTION CENTER NORMAN OK
1235 PM MDT WED MAY 21 2014
THE NWS STORM PREDICTION CENTER HAS ISSUED A
* TORNADO WATCH FOR PORTIONS OF
NORTH CENTRAL COLORADO
SOUTHEAST WYOMING
* EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 1235 PM
UNTIL 800 PM MDT.
* PRIMARY THREATS INCLUDE...
A FEW TORNADOES LIKELY WITH A COUPLE INTENSE TORNADOES POSSIBLE
WIDESPREAD LARGE HAIL LIKELY WITH ISOLATED VERY LARGE HAIL
EVENTS TO 3 INCHES IN DIAMETER POSSIBLE
SCATTERED DAMAGING WIND GUSTS TO 70 MPH POSSIBLE
THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 50 STATUTE
MILES EAST AND WEST OF A LINE FROM 50 MILES NORTHWEST OF
TORRINGTON WYOMING TO 45 MILES WEST SOUTHWEST OF LIMON COLORADO.
FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU5).
PRECAUTIONARY/PREPAREDNESS ACTIONS...
REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS.
&&
OTHER WATCH INFORMATION...CONTINUE...WW 164...
DISCUSSION...THUNDERSTORMS HAVE BEGUN TO FORM ALONG THE FRONT RANGE
OF NORTH CENTRAL CO INTO SOUTHEAST WY. ACTIVITY WILL DEVELOP OFF
THE MOUNTAINS THIS AFTERNOON INTO A MORE UNSTABLE AIR MASS...WHERE
VERTICAL SHEAR PROFILES WILL PROMOTE SUPERCELL STORMS. VERY LARGE
HAIL AND A FEW TORNADOES ARE EXPECTED.
AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 3 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
500. MEAN STORM MOTION VECTOR 25030.
...HARTSPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 20, 6:02 PM MDT | Mesoscale Discussion | SPC | Cheyenne, Kit Carson, Phillips, Sedgwick, Yuma | 88 min |
| May 20, 6:27 PM MDT | Severe Thunderstorm Watch | SPC | Cheyenne, Kit Carson, Phillips, Sedgwick, Yuma | 4 hr |
| May 20, 8:06 PM MDT | Mesoscale Discussion | SPC | Cheyenne, Kit Carson, Lincoln, Logan, Phillips, Sedgwick and 2 more | 84 min |
| May 21, 12:09 PM MDT | Mesoscale Discussion | SPC | Adams, Arapahoe, Broomfield, Denver, Elbert, Morgan and 1 more | 96 min |
| May 21, 1:42 PM MDT | Mesoscale Discussion | SPC | Baca, Bent, Crowley, El Paso, Kiowa, Las Animas and 4 more | 63 min |
| May 21, 1:58 PM MDT | Mesoscale Discussion | SPC | Broomfield, Denver, Jefferson | 62 min |
| May 21, 2:18 PM MDT | Severe Thunderstorm Watch | SPC | Baca, Bent, Crowley, El Paso, Huerfano, Kiowa and 4 more | 4 hr |
| May 21, 4:17 PM MDT | Mesoscale Discussion | SPC | Cheyenne, Elbert, Kit Carson, Lincoln, Washington, Yuma | 58 min |
| May 21, 4:48 PM MDT | Severe Thunderstorm Watch | SPC | Cheyenne, Kit Carson, Lincoln, Washington, Yuma | 6 hr |
Nearby
Tornado Watches in Colorado, 2014Tornado Watches in Wyoming, 2014Every tornado watch in 2014
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.