Alert archive / Colorado / Tornado Warnings in 2013

Tornado Warning 29, NWS Denver/Boulder, CO

June 18, 2013Arapahoe County, Colorado

NWS Denver/Boulder, CO issued this tornado warning at Jun 18, 2013, 3:18 PM MDT for Arapahoe County, Colorado. It was in force for 27 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Jun 18, 2013, 3:18 PM MDT (21:18 UTC)
Expired
Jun 18, 2013, 3:45 PM MDT
In force
27 min
Issued by
NWS Denver/Boulder, CO
Area
Storm-based polygon
Tornado
Radar indicated
Hail
0.75 in

County Arapahoe County, CO

The radar

The Denver radar (KFTG), 19 km from the middle of the area, began a volume at 21:22 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 was reported inside it

TimeReportWhereRemark
Jun 18, 3:33 PM MDTHAIL 17 Se Bennett, CO

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Jun 18, 1:53 PM MDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Denver, CO (KDNR), launched 12:00Z, 9.3 hours before the alert went out and 104 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 2013-06-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 448 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Denver, CO at 12:00Z on 2013-06-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 61 square meters per square second.193958Sfc1 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
448 J/kg
Mixed-layer CIN
-285 J/kg
Mixed-layer LCL
1028 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
61 m²/s²
0-3 km storm-relative helicity
13 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.

913 
WFUS55 KBOU 182118
TORBOU
COC005-182145-
/O.NEW.KBOU.TO.W.0029.130618T2118Z-130618T2145Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DENVER CO
318 PM MDT TUE JUN 18 2013

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A

* TORNADO WARNING FOR...
  CENTRAL ARAPAHOE COUNTY IN NORTHEAST COLORADO...

* UNTIL 345 PM MDT
    
* AT 318 PM MDT...A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A
  TORNADO WAS LOCATED 6 MILES SOUTHWEST OF STRASBURG...OR 32 MILES
  EAST OF DENVER...MOVING SOUTHEAST AT 15 MPH.

  HAZARD...TORNADO. 

  SOURCE...RADAR INDICATED ROTATION. 

  IMPACT...SPORADIC DAMAGE TO MOBILE HOMES...ROOFS AND VEHICLES. 

* LOCATIONS IMPACTED INCLUDE...
  BENNETT AND STRASBURG. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! MOVE TO A BASEMENT OR AN INTERIOR ROOM ON THE LOWEST
FLOOR OF A STURDY BUILDING. AVOID WINDOWS. IF IN A MOBILE HOME...A
VEHICLE OR OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND
PROTECT YOURSELF FROM FLYING DEBRIS.

&&

LAT...LON 3973 10446 3973 10431 3956 10428 3956 10448
      3957 10449
TIME...MOT...LOC 2118Z 305DEG 11KT 3966 10437 

TORNADO...RADAR INDICATED
HAIL...<.75IN

$$

RPK
2 follow-up statements
691 
WWUS55 KBOU 182127
SVSBOU

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
327 PM MDT TUE JUN 18 2013

COC005-182145-
/O.CON.KBOU.TO.W.0029.000000T0000Z-130618T2145Z/
ARAPAHOE CO-
327 PM MDT TUE JUN 18 2013

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 345 PM MDT FOR CENTRAL
ARAPAHOE COUNTY...
    
AT 326 PM MDT...A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO
WAS LOCATED 6 MILES SOUTH OF STRASBURG...OR 33 MILES EAST OF
DENVER...MOVING SOUTHEAST AT 10 MPH.

HAZARD...TORNADO. 

SOURCE...RADAR INDICATED ROTATION. 

IMPACT...SPORADIC DAMAGE TO MOBILE HOMES...ROOFS AND VEHICLES. 

LOCATIONS IMPACTED INCLUDE...
BENNETT AND STRASBURG. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! MOVE TO A BASEMENT OR AN INTERIOR ROOM ON THE LOWEST
FLOOR OF A STURDY BUILDING. AVOID WINDOWS. IF IN A MOBILE HOME...A
VEHICLE OR OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND
PROTECT YOURSELF FROM FLYING DEBRIS.

&&

LAT...LON 3973 10446 3973 10431 3956 10428 3956 10448
      3957 10449
TIME...MOT...LOC 2126Z 301DEG 10KT 3965 10434 

TORNADO...RADAR INDICATED
HAIL...<.75IN

$$

RPK
168 
WWUS55 KBOU 182138 RRA
SVSBOU

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
338 PM MDT TUE JUN 18 2013

COC005-182148-
/O.EXP.KBOU.TO.W.0029.000000T0000Z-130618T2145Z/
ARAPAHOE CO-
338 PM MDT TUE JUN 18 2013

...THE TORNADO WARNING FOR CENTRAL ARAPAHOE COUNTY WILL EXPIRE AT 345
PM MDT...
        
THE STORM WHICH PROMPTED THE WARNING HAS MOVED OUT OF THE AREA.
THEREFORE THE WARNING WILL BE ALLOWED TO EXPIRE.

LAT...LON 3973 10446 3973 10431 3956 10428 3956 10448
      3957 10449
TIME...MOT...LOC 2136Z 305DEG 11KT 3965 10434 

$$

RPK

The office that day

Everything else NWS Denver/Boulder, CO issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 17, 6:29 PM MDTTornado WarningBOUWashington31 min
Jun 18, 2:07 PM MDTTornado WarningBOUAdams, Arapahoe23 min
Jun 18, 2:09 PM MDTTornado WarningBOUAdams, Denver36 min
Jun 18, 2:42 PM MDTSevere Thunderstorm WarningBOUAdams, Weld33 min
Jun 18, 3:09 PM MDTTornado WarningBOUMorgan, Weld36 min
Jun 18, 3:15 PM MDTTornado WarningBOUWeld30 min
Jun 18, 3:25 PM MDTTornado WarningBOUElbert35 min
Jun 18, 3:51 PM MDTSevere Thunderstorm WarningBOUArapahoe39 min
Jun 18, 3:51 PM MDTSevere Thunderstorm WarningBOUDouglas, Elbert39 min
Jun 18, 4:16 PM MDTSevere Thunderstorm WarningBOUElbert44 min
Jun 18, 4:27 PM MDTSevere Thunderstorm WarningBOUDouglas, Elbert63 min
Jun 18, 4:34 PM MDTSevere Thunderstorm WarningBOUWeld26 min
Jun 18, 5:09 PM MDTFire Weather WatchBOUArapahoe, Douglas, Elbert, Park21 hr

Nearby

Tornado Warnings in Colorado, 2013Every tornado warning in 2013Tornadoes in 2013

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.