Alert archive / Colorado / Tornado Warnings in 2017

Tornado Warning 4, NWS Denver/Boulder, CO

May 26, 2017Washington County, Colorado

NWS Denver/Boulder, CO issued this tornado warning at May 26, 2017, 5:10 PM MDT for Washington County, Colorado. It was in force for 35 min. 3 reports 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: May 26, 2017, 5:10 PM MDT (23:10 UTC)
Expired: May 26, 2017, 5:45 PM MDT
In force: 35 min
Issued by: NWS Denver/Boulder, CO
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 1.25 in

County Washington County, CO

The radar

The Goodland radar (KGLD), 118 km from the middle of the area, began a volume at 23:13 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

Time	Report	Where	Remark
May 26, 5:15 PM MDT	TORNADO 0	8 N Arickaree School, CO	BRIEF TORNADO ON GROUND FOR 30 SECONDS
May 26, 5:15 PM MDT	TORNADO	15 S Otis, CO	BRIEF TORNADO ON GROUND FOR 30 SECONDS
May 26, 5:20 PM MDT	HAIL 1	15 S Otis, 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.

Issued	Product	Office	Lasted
May 26, 1:00 PM MDT	Severe Thunderstorm Watch	SPC	9 hr

The nearest sounding before it

Denver, CO (KDEN), launched 12:00Z, 11.2 hours before the alert went out and 25 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1013 m above ground
0-6 km bulk shear: 39 kt
0-1 km storm-relative helicity: 48 m²/s²
0-3 km storm-relative helicity: 189 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

607 
WFUS55 KBOU 262310
TORBOU
COC121-262345-
/O.NEW.KBOU.TO.W.0004.170526T2310Z-170526T2345Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Denver CO
510 PM MDT FRI MAY 26 2017

The National Weather Service in Denver Colorado has issued a

* Tornado Warning for...
  East central Washington County in northeastern Colorado...

* Until 545 PM MDT
    
* At 510 PM MDT, a severe thunderstorm capable of producing a tornado
  was located 8 miles east of Elba, or 21 miles southeast of Akron,
  moving east at 25 mph.

  HAZARD...Tornado and half dollar size hail. 

  SOURCE...Radar indicated rotation. 

  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. 

* This tornadic thunderstorm will remain over mainly rural areas of
  east central Washington County.

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 you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 3971 10280 3979 10313 4000 10314 3997 10281
TIME...MOT...LOC 2310Z 289DEG 21KT 3988 10303 

TORNADO...RADAR INDICATED
HAIL...1.25IN

$$

BAKER

2 follow-up statements

488 
WWUS55 KBOU 262333
SVSBOU

Severe Weather Statement
National Weather Service Denver CO
533 PM MDT FRI MAY 26 2017

COC121-262345-
/O.CON.KBOU.TO.W.0004.000000T0000Z-170526T2345Z/
Washington CO-
533 PM MDT FRI MAY 26 2017

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 545 PM MDT FOR EAST
CENTRAL WASHINGTON COUNTY...
    
At 532 PM MDT, a severe thunderstorm capable of producing a tornado
was located 9 miles north of Cope, or 22 miles south of Yuma, moving
east at 30 mph.

HAZARD...Tornado and half dollar size hail. 

SOURCE...Radar indicated rotation. 

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. 

This tornadic thunderstorm will remain over mainly rural areas of
east central Washington County.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Motorists should not take shelter under highway overpasses. If you
cannot safely drive away from the tornado, as a last resort, either
park your vehicle and stay put, or abandon your vehicle and lie down
in a low lying area and protect yourself from flying debris.

Heavy rainfall may hide this tornado. Do not wait to see or hear the
tornado. TAKE COVER NOW!

&&

LAT...LON 3976 10301 3991 10298 3988 10281 3971 10280
TIME...MOT...LOC 2332Z 284DEG 24KT 3981 10285 

TORNADO...RADAR INDICATED
HAIL...1.25IN

$$

BAKER

742 
WWUS55 KBOU 262347
SVSBOU

Severe Weather Statement
National Weather Service Denver CO
547 PM MDT FRI MAY 26 2017

COC121-262356-
/O.EXP.KBOU.TO.W.0004.000000T0000Z-170526T2345Z/
Washington CO-
547 PM MDT FRI MAY 26 2017

...THE TORNADO WARNING FOR EAST CENTRAL WASHINGTON COUNTY HAS
EXPIRED...
        
The storm which prompted the warning has moved out of the area.
Therefore the warning has been allowed to expire.  However, hail up 
to nickle size and wind gusts to 40 mph are still possible with this 
thunderstorm.

A severe thunderstorm watch remains in effect until 800 PM MDT for
northeastern Colorado.

LAT...LON 3976 10301 3991 10298 3988 10281 3971 10280
TIME...MOT...LOC 2346Z 289DEG 21KT 3978 10275 

$$

BAKER

The office that day

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

Issued	Product	Office	Counties	Lasted
May 25, 6:30 PM MDT	Special Weather Statement	BOU	Weld	45 min
May 25, 6:46 PM MDT	Severe Thunderstorm Warning	BOU	Morgan, Weld	44 min
May 25, 7:13 PM MDT	Special Weather Statement	BOU	Adams, Morgan	47 min
May 25, 7:17 PM MDT	Special Weather Statement	BOU	Adams, Morgan	43 min
May 25, 7:30 PM MDT	Severe Thunderstorm Warning	BOU	Logan, Morgan, Washington, Weld	31 min
May 25, 7:54 PM MDT	Special Weather Statement	BOU	Morgan, Washington	36 min
May 25, 7:55 PM MDT	Special Weather Statement	BOU	Morgan, Washington	35 min
May 26, 7:27 AM MDT	River Flood Advisory	BOU	Weld	4 days
May 26, 1:16 PM MDT	Special Weather Statement	BOU	Denver	44 min
May 26, 2:01 PM MDT	Special Weather Statement	BOU	Adams, Arapahoe	59 min
May 26, 2:21 PM MDT	Severe Thunderstorm Warning	BOU	Weld	13 min
May 26, 2:32 PM MDT	Special Weather Statement	BOU	Adams	43 min
May 26, 3:12 PM MDT	Special Weather Statement	BOU	Morgan	48 min
May 26, 3:14 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Morgan, Washington	46 min
May 26, 4:09 PM MDT	Severe Thunderstorm Warning	BOU	Morgan, Washington	36 min
May 26, 4:19 PM MDT	Tornado Warning	BOU	Washington	26 min
May 26, 4:48 PM MDT	Severe Thunderstorm Warning	BOU	Washington	42 min
May 26, 4:53 PM MDT	Severe Thunderstorm Warning	BOU	Douglas, Elbert	52 min
May 26, 5:23 PM MDT	Special Weather Statement	BOU	Elbert	52 min
May 26, 5:46 PM MDT	Special Weather Statement	BOU	Morgan	44 min

Nearby

Tornado Warnings in Colorado, 2017 Every tornado warning in 2017 Tornadoes in 2017

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.