Alert archive / Wyoming / Tornado Watches in 2015

Tornado Watch 251

June 3, 201512 counties in Colorado; 4 counties in Nebraska; 13 counties in Wyoming

The Storm Prediction Center issued this tornado watch at Jun 3, 2015, 2:03 PM MDT for 12 counties in Colorado; 4 counties in Nebraska; 13 counties in Wyoming. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued
Jun 3, 2015, 2:03 PM MDT (20:03 UTC)
Expired
Jun 3, 2015, 9:00 PM MDT
In force
7 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
60 kt
All 29 counties

Adams County, CO, Arapahoe County, CO, Boulder County, CO, Broomfield County, CO, Denver County, CO, Douglas County, CO, El Paso County, CO, Elbert County, CO, Jefferson County, CO, Larimer County, CO, Morgan County, CO, Weld County, CO, Banner County, NE, Kimball County, NE, Scotts Bluff County, NE, Sioux County, NE, Albany County, WY, Campbell County, WY, Converse County, WY, Fremont County, WY, Goshen County, WY, Hot Springs County, WY, Johnson County, WY, Laramie County, WY, Natrona County, WY, Niobrara County, WY, Platte County, WY, Washakie County, WY, Weston County, WY

The radar

The Cheyenne radar (KCYS), 11 km from the middle of the area, began a volume at 20:04 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
50%
One or more EF2 to EF5 tornadoes
20%
Ten or more severe wind reports
30%
One or more gusts of 65 knots or more
10%
Ten or more severe hail reports
60%
One or more hailstones of 2 inches or more
50%
Six or more combined severe hail and wind reports
90%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Jun 3, 3:24 PM MDTSevere Thunderstorm WarningBOUDouglas51 min
Jun 3, 4:23 PM MDTSevere Thunderstorm WarningBOUDouglas, Jefferson37 min
Jun 3, 4:32 PM MDTSevere Thunderstorm WarningRIWBig Horn, Hot Springs, Washakie43 min
Jun 3, 4:37 PM MDTSevere Thunderstorm WarningBOUDouglas, Elbert23 min
Jun 3, 4:43 PM MDTSevere Thunderstorm WarningRIWNatrona47 min
Jun 3, 4:59 PM MDTSevere Thunderstorm WarningBOUAdams, Arapahoe, Denver, Douglas, Jefferson30 min
Jun 3, 5:03 PM MDTSevere Thunderstorm WarningBOUElbert57 min
Jun 3, 5:16 PM MDTSevere Thunderstorm WarningRIWWashakie44 min
Jun 3, 5:24 PM MDTSevere Thunderstorm WarningBOUAdams, Arapahoe, Douglas, Elbert38 min
Jun 3, 5:29 PM MDTSevere Thunderstorm WarningBOUAdams, Broomfield, Denver, Jefferson46 min
Jun 3, 5:38 PM MDTSevere Thunderstorm WarningRIWJohnson52 min
Jun 3, 5:55 PM MDTSevere Thunderstorm WarningRIWJohnson, Natrona26 min
Jun 3, 6:02 PM MDTSevere Thunderstorm WarningBOUArapahoe, Douglas, Elbert43 min
Jun 3, 6:20 PM MDTFlash Flood WarningRIWWashakie3 hr
Jun 3, 6:22 PM MDTSevere Thunderstorm WarningUNRCampbell53 min
Jun 3, 6:29 PM MDTSevere Thunderstorm WarningBOUClear Creek, Jefferson46 min
Jun 3, 6:29 PM MDTSevere Thunderstorm WarningRIWJohnson46 min
Jun 3, 6:41 PM MDTSevere Thunderstorm WarningBOUElbert64 min
Jun 3, 6:41 PM MDTSevere Thunderstorm WarningRIWJohnson49 min
Jun 3, 6:49 PM MDTSevere Thunderstorm WarningRIWFremont, Hot Springs41 min
Jun 3, 7:04 PM MDTSevere Thunderstorm WarningCYSGoshen, Platte41 min
Jun 3, 7:10 PM MDTFlash Flood WarningRIWJohnson3 hr
Jun 3, 7:11 PM MDTSevere Thunderstorm WarningUNRCampbell37 min
Jun 3, 7:12 PM MDTSevere Thunderstorm WarningRIWJohnson63 min
Jun 3, 7:18 PM MDTSevere Thunderstorm WarningBOUBoulder, Larimer, Weld15 min
Jun 3, 7:20 PM MDTFlash Flood WarningUNRCampbell3 hr
Jun 3, 7:41 PM MDTSevere Thunderstorm WarningCYSConverse36 min
Jun 3, 7:41 PM MDTFlash Flood WarningRIWJohnson3 hr
Jun 3, 7:45 PM MDTSevere Thunderstorm WarningBOUAdams, Arapahoe45 min
Jun 3, 7:58 PM MDTSevere Thunderstorm WarningBOUWeld32 min
Jun 3, 8:03 PM MDTSevere Thunderstorm WarningCYSConverse, Goshen, Niobrara, Platte42 min
Jun 3, 8:13 PM MDTSevere Thunderstorm WarningBOULarimer32 min
Jun 3, 8:25 PM MDTSevere Thunderstorm WarningCYSLaramie50 min
Jun 3, 8:29 PM MDTSevere Thunderstorm WarningBOUAdams, Arapahoe61 min
Jun 3, 8:43 PM MDTSevere Thunderstorm WarningCYSGoshen, Niobrara, Platte47 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, 8.1 hours before the alert went out and 201 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 2015-06-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 67 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, Denver, CO at 12:00Z on 2015-06-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -7 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
67 J/kg
Mixed-layer CIN
-335 J/kg
Mixed-layer LCL
1609 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
-7 m²/s²
0-3 km storm-relative helicity
11 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

234 
WWUS20 KWNS 032000
SEL1  
SPC WW 032000
COZ000-NEZ000-WYZ000-040300-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 251
NWS STORM PREDICTION CENTER NORMAN OK
200 PM MDT WED JUN 3 2015

THE NWS STORM PREDICTION CENTER HAS ISSUED A

* TORNADO WATCH FOR PORTIONS OF 
  EASTERN COLORADO
  WESTERN NEBRASKA PANHANDLE
  EASTERN WYOMING

* EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 200 PM
  UNTIL 900 PM MDT.

* PRIMARY THREATS INCLUDE...
  A FEW TORNADOES POSSIBLE
  SCATTERED LARGE HAIL LIKELY WITH ISOLATED VERY LARGE HAIL EVENTS
    TO 2 INCHES IN DIAMETER POSSIBLE
  ISOLATED DAMAGING WIND GUSTS TO 70 MPH POSSIBLE

SUMMARY...SUPERCELLS ARE EXPECTED TO DEVELOP ACROSS THE WATCH AREA
THIS AFTERNOON WITH A RISK FOR LARGE HAIL AND A FEW TORNADOES.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 60 STATUTE
MILES EAST AND WEST OF A LINE FROM 35 MILES WEST SOUTHWEST OF
LIMON COLORADO TO 100 MILES NORTH OF DOUGLAS WYOMING.  FOR A
COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE
UPDATE (WOUS64 KWNS WOU1).

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.

&&

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
500. MEAN STORM MOTION VECTOR 27020.


...MEAD

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 3, 2:01 AM MDTMesoscale DiscussionSPCSedgwick89 min
Jun 3, 12:34 PM MDTMesoscale DiscussionSPCAdams, Arapahoe, Broomfield, Denver, Elbert, Larimer and 4 more86 min
Jun 2, 8:01 PM MDTMesoscale DiscussionSPCArthur, Blaine, Boyd, Brown, Cherry, Custer and 17 more89 min
Jun 2, 8:25 PM MDTSevere Thunderstorm WatchSPCBlaine, Boyd, Brown, Buffalo, Custer, Dawson and 14 more5 hr
Jun 2, 10:57 PM MDTMesoscale DiscussionSPCBlaine, Boyd, Brown, Custer, Garfield, Greeley and 8 more2 hr
Jun 3, 12:03 AM MDTSevere Thunderstorm WatchSPCAdams, Buffalo, Clay, Dawson, Fillmore, Greeley and 11 more3 hr
Jun 3, 3:05 PM MDTMesoscale DiscussionSPCFranklin, Furnas, Harlan, Webster115 min
Jun 3, 5:33 PM MDTTornado WatchSPCAdams, Clay, Fillmore, Franklin, Furnas, Gage and 11 more7 hr

Nearby

Tornado Watches in Wyoming, 2015Tornado Watches in Colorado, 2015Tornado Watches in Nebraska, 2015Every tornado watch in 2015

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.