Alert archive / Colorado / Flash Flood Warnings in 2021

Flash Flood Warning 33, NWS Grand Junction, CO

July 25, 2021Eagle County, Colorado

NWS Grand Junction, CO issued this flash flood warning at Jul 25, 2021, 4:06 PM MDT for Eagle County, Colorado. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Jul 25, 2021, 4:06 PM MDT (22:06 UTC)
Expired: Jul 25, 2021, 7:15 PM MDT
In force: 3 hr
Issued by: NWS Grand Junction, CO
Area: Storm-based polygon
Flood severity: None

County Eagle County, CO

The radar

The Grand Junction radar (KGJX), 120 km from the middle of the area, began a volume at 22:05 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

Grand Junction, CO (KGJT), launched 12:00Z, 10.1 hours before the alert went out and 142 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: 2095 m above ground
0-6 km bulk shear: 3 kt
0-1 km storm-relative helicity: 6 m²/s²
0-3 km storm-relative helicity: 70 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

691 
WGUS55 KGJT 252206
FFWGJT
COC037-260115-
/O.NEW.KGJT.FF.W.0033.210725T2206Z-210726T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Grand Junction CO
406 PM MDT Sun Jul 25 2021

The National Weather Service in Grand Junction has issued a

* Flash Flood Warning for...
  Southwestern Eagle County in west central Colorado...

* Until 715 PM MDT.

* At 406 PM MDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. The expected rainfall rate is 1 
  to 2 inches in 1 hour. Flash flooding is ongoing or expected to 
  begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  Frying Pan Road in between Basalt and Ruedi Reservoir.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

LAT...LON 3937 10686 3937 10692 3939 10692 3940 10687

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1-2 INCHES IN 1 HOUR

$$

KJS

1 follow-up statement

495 
WGUS75 KGJT 260115
FFSGJT

Flash Flood Statement
National Weather Service Grand Junction CO
715 PM MDT Sun Jul 25 2021

COC037-260125-
/O.EXP.KGJT.FF.W.0033.000000T0000Z-210726T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Eagle CO-
715 PM MDT Sun Jul 25 2021

...FLASH FLOOD WARNING HAS EXPIRED FOR SOUTHWESTERN EAGLE COUNTY...

The heavy rain has ended. Flooding is no longer expected to pose a 
threat. Please continue to heed remaining road closures.

LAT...LON 3937 10686 3937 10692 3939 10692 3940 10687

$$

NL

The office that day

Everything else NWS Grand Junction, CO issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 25, 1:02 PM MDT	Flash Flood Watch	GJT	Eagle, Garfield, Moffat, Pitkin, Rio Blanco, Routt	7 hr
Jul 25, 1:38 PM MDT	Areal Flood Advisory	GJT	Dolores, San Miguel	112 min
Jul 25, 3:25 PM MDT	Flash Flood Warning	GJT	Gunnison, Pitkin	3 hr
Jul 25, 3:53 PM MDT	Areal Flood Advisory	GJT	Rio Blanco	2 hr
Jul 25, 4:45 PM MDT	Areal Flood Advisory	GJT	Montezuma	3 hr
Jul 25, 4:53 PM MDT	Special Weather Statement	GJT	Rio Blanco	22 min
Jul 25, 4:54 PM MDT	Flash Flood Warning	GJT	Montrose	3 hr
Jul 25, 5:20 PM MDT	Special Weather Statement	GJT	Rio Blanco	40 min
Jul 25, 5:46 PM MDT	Areal Flood Advisory	GJT	Rio Blanco	3 hr

Nearby

Flash Flood Warnings in Colorado, 2021 Every flash flood warning in 2021

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.