Alert archive / Colorado / Flash Flood Warnings in 2017

Flash Flood Warning 49, NWS Pueblo, CO

August 21, 2017Custer County, Fremont County, Saguache County, Colorado

NWS Pueblo, CO issued this flash flood warning at Aug 21, 2017, 5:18 PM MDT for Custer County, Fremont County, Saguache 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
Aug 21, 2017, 5:18 PM MDT (23:18 UTC)
Expired
Aug 21, 2017, 8:15 PM MDT
In force
3 hr
Issued by
NWS Pueblo, CO
Area
Storm-based polygon
Flood severity
None

Counties Custer County, CO, Fremont County, CO, Saguache County, CO

The radar

The Pueblo radar (KPUX), 139 km from the middle of the area, began a volume at 23:17 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, 11.3 hours before the alert went out and 254 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, Grand Junction, CO at 12:00Z on 2017-08-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Grand Junction, CO at 12:00Z on 2017-08-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 27 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
3061 m above ground
0-6 km bulk shear
14 kt
0-1 km storm-relative helicity
27 m²/s²
0-3 km storm-relative helicity
11 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

776 
WGUS55 KPUB 212318
FFWPUB
COC027-043-109-220215-
/O.NEW.KPUB.FF.W.0049.170821T2318Z-170822T0215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Pueblo CO
518 PM MDT MON AUG 21 2017

The National Weather Service in Pueblo has issued a

* Flash Flood Warning for...
  Southwestern Fremont County in central Colorado...
  Northwestern Custer County in southeastern Colorado...
  Northeastern Saguache County in central Colorado...

* Until 815 PM MDT

* At 515 PM MDT, Doppler radar indicated slow moving thunderstorms 
  producing heavy rain moving over the western half of the Hayden 
  Pass burn scar. Flash flooding is expected to begin shortly.

* Flash flooding will remain over mainly rural areas of southwestern
  Fremont...northwestern Custer and northeastern Saguache Counties.
  Excessive rainfall over the burn scar will result in debris flow. 
  The debris flow can consist of rock, mud, vegetation and other 
  loose materials.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move away from recently burned areas. Life-threatening flooding of
creeks, roads and normally dry arroyos is likely. The heavy rains
will likely trigger rockslides, mudslides and debris flows in steep
terrain, especially in and around these areas.

&&

LAT...LON 3835 10571 3825 10572 3827 10585 3834 10585

$$

28
3 follow-up statements
182 
WGUS75 KPUB 212331
FFSPUB

Flash Flood Statement
National Weather Service Pueblo CO
531 PM MDT MON AUG 21 2017

COC027-043-109-220215-
/O.CON.KPUB.FF.W.0049.000000T0000Z-170822T0215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Fremont CO-Custer CO-Saguache CO-
531 PM MDT MON AUG 21 2017

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 815 PM MDT FOR
SOUTHWESTERN FREMONT...NORTHWESTERN CUSTER AND NORTHEASTERN SAGUACHE
COUNTIES...

At 530 PM MDT, Doppler radar indicated thunderstorms producing heavy 
rain moving over western portions of the Hayden Pass burn scar. 
Flash flooding is expected.

Excessive rainfall over the burn scar will result in debris flow.
The debris flow can consist of rock, mud, vegetation and other loose 
materials.

Flash flooding will remain over mainly rural areas of southwestern 
Fremont...northwestern Custer and northeastern Saguache Counties.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move away from recently burned areas. Life-threatening flooding of 
creeks, roads and normally dry arroyos is likely. The heavy rains 
will likely trigger rockslides, mudslides and debris flows in steep 
terrain, especially in and around these areas.

&&

LAT...LON 3835 10571 3825 10572 3827 10585 3834 10585

$$

28
344 
WGUS75 KPUB 220018
FFSPUB

Flash Flood Statement
National Weather Service Pueblo CO
618 PM MDT MON AUG 21 2017

COC027-043-109-220215-
/O.CON.KPUB.FF.W.0049.000000T0000Z-170822T0215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Fremont CO-Custer CO-Saguache CO-
618 PM MDT MON AUG 21 2017

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 815 PM MDT FOR
SOUTHWESTERN FREMONT...NORTHWESTERN CUSTER AND NORTHEASTERN SAGUACHE
COUNTIES...

At 616 PM MDT, Doppler radar indicated thunderstorms producing 
generally light rain across the Hayden Pass burn scar.  However, 
heavy rain earlier may be causing flash flooding over western 
portions of the burn scar.  

Excessive rainfall over the burn scar will result in debris flow. 
The debris flow can consist of rock, mud, vegetation and other loose 
materials.

Flash flooding will remain over mainly rural areas of southwestern
Fremont...northwestern Custer and northeastern Saguache Counties.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move away from recently burned areas. Life-threatening flooding of
creeks, roads and normally dry arroyos is likely. The heavy rains
will likely trigger rockslides, mudslides and debris flows in steep
terrain, especially in and around these areas.

&&

LAT...LON 3835 10571 3825 10572 3827 10585 3834 10585

$$

28
494 
WGUS75 KPUB 220043
FFSPUB

Flash Flood Statement
National Weather Service Pueblo CO
643 PM MDT MON AUG 21 2017

COC027-043-109-220052-
/O.CAN.KPUB.FF.W.0049.000000T0000Z-170822T0215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Fremont CO-Custer CO-Saguache CO-
643 PM MDT MON AUG 21 2017

...THE FLASH FLOOD WARNING FOR SOUTHWESTERN FREMONT...NORTHWESTERN
CUSTER AND NORTHEASTERN SAGUACHE COUNTIES IS CANCELLED...

The heavy rain has ended on the Hayden Pass burn scar.  There will 
continue to be some light rain in the area through at least 730 pm, 
but flooding is no longer expected to pose a threat. Please continue 
to heed any remaining road closures.

LAT...LON 3835 10571 3825 10572 3827 10585 3834 10585

$$

28

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 20, 6:20 PM MDTSpecial Weather StatementPUBPueblo40 min
Aug 20, 7:04 PM MDTSpecial Weather StatementPUBPueblo41 min
Aug 21, 4:09 PM MDTAreal Flood AdvisoryPUBFremont3 hr
Aug 21, 4:26 PM MDTSpecial Weather StatementPUBSaguache34 min
Aug 21, 4:42 PM MDTSpecial Weather StatementPUBFremont33 min
Aug 21, 5:04 PM MDTFlash Flood WarningPUBCuster, Pueblo3 hr

Nearby

Flash Flood Warnings in Colorado, 2017Every flash flood warning 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.