Alert archive / Colorado / Tornado Warnings in 2020

Tornado Warning 5, NWS Denver/Boulder, CO

August 15, 2020Washington County, Colorado

NWS Denver/Boulder, CO issued this tornado warning at Aug 15, 2020, 6:03 PM MDT for Washington County, Colorado. It was in force for 27 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: Aug 15, 2020, 6:03 PM MDT (00:03 UTC)
Expired: Aug 15, 2020, 6:30 PM MDT
In force: 27 min
Issued by: NWS Denver/Boulder, CO
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 1.0 in

County Washington County, CO

The radar

The Denver radar (KFTG), 105 km from the middle of the area, began a volume at 00:07 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 nearest sounding before it

Denver, CO (KDNR), launched 00:00Z, 0.1 hours before the alert went out and 24 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: 76 J/kg
Mixed-layer CIN: -105 J/kg
Mixed-layer LCL: 3509 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: 1 m²/s²
0-3 km storm-relative helicity: 46 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.0

Open this sounding in Storm Lab

The text

As transmitted.

703 
WFUS55 KBOU 160003
TORBOU
COC121-160030-
/O.NEW.KBOU.TO.W.0005.200816T0003Z-200816T0030Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Denver CO
603 PM MDT Sat Aug 15 2020

The National Weather Service in Denver Colorado has issued a

* Tornado Warning for...
  Central Washington County in northeastern Colorado...

* Until 630 PM MDT.
    
* At 602 PM MDT, a severe thunderstorm capable of producing a tornado
  was located 9 miles east of Gary, or 11 miles southwest of Akron,
  moving south at 5 mph.

  HAZARD...Tornado and quarter size hail.

  SOURCE...Radar indicated rotation.

  IMPACT...Expect damage to mobile homes, roofs, and vehicles.

* This tornadic thunderstorm will remain over mainly rural areas of
  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 4013 10347 4016 10329 3996 10316 3993 10346
TIME...MOT...LOC 0002Z 357DEG 6KT 4009 10341 

TORNADO...RADAR INDICATED
HAIL...1.00IN

$$

BOWEN

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 15, 6:38 PM MDT	Severe Thunderstorm Warning	BOU	Lincoln	52 min
Aug 15, 7:20 PM MDT	Severe Thunderstorm Warning	BOU	Lincoln	40 min
Aug 15, 7:54 PM MDT	Severe Thunderstorm Warning	BOU	Lincoln	36 min
Aug 16, 3:00 PM MDT	Special Weather Statement	BOU	Lincoln	45 min
Aug 16, 3:34 PM MDT	Severe Thunderstorm Warning	BOU	Lincoln	41 min
Aug 16, 4:50 PM MDT	Severe Thunderstorm Warning	BOU	Lincoln	25 min
Aug 16, 5:28 PM MDT	Special Weather Statement	BOU	Crowley	47 min

Nearby

Tornado Warnings in Colorado, 2020 Every tornado warning in 2020 Tornadoes in 2020

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.