Alert archive / Colorado / Tornado Warnings in 2015

Tornado Warning 26, NWS Denver/Boulder, CO

June 4, 2015Boulder County, Colorado

NWS Denver/Boulder, CO issued this tornado warning at Jun 4, 2015, 6:37 PM MDT for Boulder County, Colorado. It was in force for 23 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Jun 4, 2015, 6:37 PM MDT (00:37 UTC)
Expired: Jun 4, 2015, 7:00 PM MDT
In force: 23 min
Issued by: NWS Denver/Boulder, CO
Area: Storm-based polygon
Tornado: Observed
Hail: 1.25 in

County Boulder County, CO

The radar

The Denver radar (KFTG), 67 km from the middle of the area, began a volume at 00:38 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.

The watch it was issued in

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

Issued	Product	Office	Lasted
Jun 4, 2:20 PM MDT	Tornado Watch	SPC	8 hr

The nearest sounding before it

Denver, CO (KDEN), launched 00:00Z, 0.6 hours before the alert went out and 164 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 945 J/kg
Mixed-layer CIN: -49 J/kg
Mixed-layer LCL: 2145 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: -49 m²/s²
0-3 km storm-relative helicity: 26 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.

782 
WFUS55 KBOU 050037
TORBOU
COC013-050100-
/O.NEW.KBOU.TO.W.0026.150605T0037Z-150605T0100Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DENVER CO
637 PM MDT THU JUN 4 2015

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A

* TORNADO WARNING FOR...
  NORTHEASTERN BOULDER COUNTY IN CENTRAL COLORADO...

* UNTIL 700 PM MDT

* AT 637 PM MDT...A CONFIRMED TORNADO WAS LOCATED NEAR BERTHOUD...OR
  21 MILES SOUTH OF FORT COLLINS...MOVING WEST AT 15 MPH.

  HAZARD...DAMAGING TORNADO AND HALF DOLLAR SIZE HAIL. 

  SOURCE...WEATHER SPOTTERS CONFIRMED TORNADO. 

  IMPACT...FLYING DEBRIS WILL BE DANGEROUS TO THOSE CAUGHT WITHOUT 
           SHELTER. MOBILE HOMES WILL BE DAMAGED OR DESTROYED. 
           DAMAGE TO ROOFS...WINDOWS AND VEHICLES WILL OCCUR.  TREE 
           DAMAGE IS LIKELY. 

* LOCATIONS IMPACTED INCLUDE...
  NORTHERN LONGMONT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4020 10506 4018 10515 4026 10516 4026 10506
TIME...MOT...LOC 0037Z 069DEG 12KT 4025 10508 

TORNADO...OBSERVED
HAIL...1.25IN

$$

DANKERS

2 follow-up statements

102 
WWUS55 KBOU 050054
SVSBOU

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
654 PM MDT THU JUN 4 2015

COC013-050100-
/O.CON.KBOU.TO.W.0026.000000T0000Z-150605T0100Z/
BOULDER CO-
654 PM MDT THU JUN 4 2015

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 700 PM MDT FOR
NORTHEASTERN BOULDER COUNTY...
    
AT 653 PM MDT...A CONFIRMED TORNADO WAS LOCATED 4 MILES NORTHWEST OF
LONGMONT...OR 22 MILES SOUTH OF FORT COLLINS...MOVING WEST AT 15 MPH.

HAZARD...DAMAGING TORNADO AND HALF DOLLAR SIZE HAIL. 

SOURCE...WEATHER SPOTTERS CONFIRMED TORNADO. 

IMPACT...FLYING DEBRIS WILL BE DANGEROUS TO THOSE CAUGHT WITHOUT 
         SHELTER. MOBILE HOMES WILL BE DAMAGED OR DESTROYED. DAMAGE 
         TO ROOFS...WINDOWS AND VEHICLES WILL OCCUR.  TREE DAMAGE IS 
         LIKELY. 

LOCATIONS IMPACTED INCLUDE...
NORTHERN LONGMONT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TO REPEAT...A TORNADO IS ON THE GROUND. 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 4020 10506 4018 10515 4026 10516 4026 10506
TIME...MOT...LOC 0053Z 069DEG 12KT 4023 10515 

TORNADO...OBSERVED
HAIL...1.25IN

$$

DANKERS

678 
WWUS55 KBOU 050101
SVSBOU

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
701 PM MDT THU JUN 4 2015

COC013-050110-
/O.EXP.KBOU.TO.W.0026.000000T0000Z-150605T0100Z/
BOULDER CO-
701 PM MDT THU JUN 4 2015

...THE TORNADO WARNING FOR NORTHEASTERN BOULDER COUNTY HAS EXPIRED...
    
THE TORNADO WARNING THAT WAS PREVIOUSLY IN EFFECT HAS BEEN REISSUED 
FOR NORTHEAST BOULDER AND SOUTHEAST LARIMER COUNTIES AND IS IN 
EFFECT UNTIL 730 PM MDT. PLEASE REFER TO THAT BULLETIN FOR THE 
LATEST SEVERE WEATHER INFORMATION.  HOWEVER SMALL HAIL IS STILL 
POSSIBLE WITH THIS THUNDERSTORM.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 1000 PM MDT FOR CENTRAL
COLORADO.

LAT...LON 4020 10506 4018 10515 4026 10516 4026 10506
TIME...MOT...LOC 0059Z 069DEG 12KT 4023 10515 

$$

DANKERS

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 4, 6:11 PM MDT	Severe Thunderstorm Warning	BOU	Boulder, Larimer, Weld	34 min
Jun 4, 6:26 PM MDT	Tornado Warning Tornado observed	BOU	Elbert	34 min
Jun 4, 6:32 PM MDT	Severe Thunderstorm Warning	BOU	Larimer	28 min
Jun 4, 6:38 PM MDT	Tornado Warning Tornado observed	BOU	Boulder, Larimer, Weld	22 min
Jun 4, 6:58 PM MDT	Tornado Warning	BOU	Elbert, Lincoln	32 min
Jun 4, 7:03 PM MDT	Tornado Warning Tornado observed	BOU	Boulder, Larimer	27 min
Jun 4, 7:15 PM MDT	Flash Flood Warning Emergency	BOU	Boulder, Larimer, Weld	3 hr
Jun 4, 7:30 PM MDT	Tornado Warning	BOU	Elbert	30 min
Jun 4, 7:54 PM MDT	Severe Thunderstorm Warning	BOU	Boulder	51 min
Jun 4, 8:40 PM MDT	River Flood Advisory	BOU	Boulder	6 hr
Jun 4, 8:49 PM MDT	Severe Thunderstorm Warning	BOU	Boulder	26 min
Jun 4, 9:13 PM MDT	Areal Flood Warning	BOU	Boulder, Larimer, Weld	12 hr
Jun 4, 9:17 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Boulder, Broomfield, Weld	43 min
Jun 4, 9:19 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Arapahoe, Denver	26 min
Jun 4, 9:42 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Broomfield, Denver, Jefferson	33 min
Jun 4, 9:47 PM MDT	Areal Flood Advisory	BOU	Adams, Denver, Jefferson	3 hr
Jun 4, 9:58 PM MDT	Flash Flood Warning Emergency	BOU	Boulder, Larimer	6 hr
Jun 4, 10:39 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Denver	22 min
Jun 4, 11:00 PM MDT	Severe Thunderstorm Warning	BOU	Denver, Jefferson	30 min
Jun 4, 11:16 PM MDT	Areal Flood Advisory	BOU	Denver, Jefferson	3 hr
Jun 5, 12:42 AM MDT	Severe Thunderstorm Warning	BOU	Arapahoe, Denver, Jefferson	33 min
Jun 5, 12:48 AM MDT	Areal Flood Advisory	BOU	Adams, Denver, Jefferson	117 min
Jun 5, 12:52 AM MDT	Severe Thunderstorm Warning	BOU	Elbert, Lincoln	23 min
Jun 5, 1:09 AM MDT	Severe Thunderstorm Warning	BOU	Elbert	36 min
Jun 5, 1:45 AM MDT	Severe Thunderstorm Warning	BOU	Adams, Denver	30 min
Jun 5, 2:02 AM MDT	Severe Thunderstorm Warning	BOU	Elbert	28 min
Jun 5, 2:21 AM MDT	Areal Flood Advisory	BOU	Arapahoe, Elbert, Lincoln, Washington	3 hr
Jun 5, 2:26 AM MDT	Tornado Warning	BOU	Elbert	34 min
Jun 5, 3:03 AM MDT	Flash Flood Warning	BOU	Elbert, Lincoln	3 hr
Jun 5, 4:27 AM MDT	Flash Flood Watch	BOU	Adams, Arapahoe, Boulder, Broomfield, Clear Creek, Denver and 13 more	18 hr
Jun 5, 6:12 AM MDT	River Flood Warning	BOU	Adams	38 hr
Jun 5, 9:10 AM MDT	River Flood Warning	BOU	Morgan	11 days
Jun 5, 9:10 AM MDT	River Flood Warning	BOU	Logan, Morgan, Washington	4 days
Jun 5, 12:52 PM MDT	Tornado Warning	BOU	Arapahoe, Douglas	23 min
Jun 5, 1:08 PM MDT	Tornado Warning	BOU	Arapahoe, Douglas, Elbert	37 min
Jun 5, 1:25 PM MDT	Areal Flood Advisory	BOU	Adams, Arapahoe, Douglas	3 hr
Jun 5, 1:48 PM MDT	Tornado Warning	BOU	Adams, Arapahoe	42 min
Jun 5, 2:17 PM MDT	Tornado Warning	BOU	Arapahoe, Douglas, Elbert	43 min
Jun 5, 3:04 PM MDT	Tornado Warning	BOU	Adams, Arapahoe	26 min
Jun 5, 3:27 PM MDT	Tornado Warning	BOU	Adams, Arapahoe	33 min
Jun 5, 3:41 PM MDT	Severe Thunderstorm Warning	BOU	Lincoln, Washington	49 min
Jun 5, 4:03 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Morgan	42 min
Jun 5, 4:21 PM MDT	River Flood Warning	BOU	Boulder	65 hr
Jun 5, 4:31 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Arapahoe	29 min
Jun 5, 4:34 PM MDT	Severe Thunderstorm Warning	BOU	Lincoln, Washington	26 min
Jun 5, 4:36 PM MDT	Areal Flood Advisory	BOU	Lincoln, Washington	3 hr
Jun 5, 4:44 PM MDT	Tornado Warning	BOU	Washington	31 min
Jun 5, 4:58 PM MDT	Tornado Warning	BOU	Adams, Washington	32 min
Jun 5, 5:24 PM MDT	Severe Thunderstorm Warning	BOU	Logan, Morgan, Washington	39 min

Nearby

Tornado Warnings in Colorado, 2015 Every tornado warning in 2015 Tornadoes 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.