Alert archive / Colorado / Flash Flood Warnings in 2012

Flash Flood Warning 22, NWS Denver/Boulder, CO

July 27, 2012Larimer County, Colorado

NWS Denver/Boulder, CO issued this flash flood warning at Jul 27, 2012, 1:07 PM MDT for Larimer County, Colorado. It was in force for 3 hr. 1 report 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
Jul 27, 2012, 1:07 PM MDT (19:07 UTC)
Expired
Jul 27, 2012, 4:00 PM MDT
In force
3 hr
Issued by
NWS Denver/Boulder, CO
Area
Storm-based polygon
Flood severity
None

County Larimer County, CO

The radar

The Cheyenne radar (KCYS), 77 km from the middle of the area, began a volume at 19:08 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

TimeReportWhereRemark
Jul 27, 1:50 PM MDTFLASH FLOOD2 E Mishowaka, COEASTBOUND HIGHWAY 14 AT MILE MARKER 106 IS COMPLETELY BLOCKED BY DEBRIS.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Denver, CO (KDNR), launched 12:00Z, 7.1 hours before the alert went out and 206 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, Denver, CO at 12:00Z on 2012-07-27Temperature 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, Denver, CO at 12:00Z on 2012-07-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 1 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
2426 m above ground
0-6 km bulk shear
4 kt
0-1 km storm-relative helicity
1 m²/s²
0-3 km storm-relative helicity
-29 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.

137 
WGUS55 KBOU 271907
FFWBOU
COC069-272200-
/O.NEW.KBOU.FF.W.0022.120727T1907Z-120727T2200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE DENVER CO
107 PM MDT FRI JUL 27 2012

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CENTRAL LARIMER COUNTY IN NORTH CENTRAL COLORADO

* UNTIL 400 PM MDT

* AT 102 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  VERY HEAVY RAIN FROM A THUNDERSTORM 6 MILES SOUTHWEST OF           
  MISHOWAKA...OR 19 MILES WEST OF FORT COLLINS. THIS STORM WAS       
  MOVING NORTHEAST AT 10 MPH.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO THE HIGH   
  PARK BURN AREA...MISHOWAKA AND BUCKHORN MOUNTAIN.

DOPPLER RADAR ESTIMATES THAT RAIN FROM THE STORM IS FALLING AT THE 
RATE OF AROUND ONE INCH PER HOUR. 

THIS INCLUDES THE FOLLOWING STREAMS AND DRAINAGES...
CACHE LA POUDRE RIVER...SOUTH FORK CACHE LA POUDRE RIVER...
PENDERGRASS CREEK...BENNETT CREEK...GORDON CREEK...REDSTONE CREEK AND
BUCKHORN CREEK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM THIS STORM WILL CAUSE FLASH FLOODING OF CREEKS
AND STREAMS...ROADS...AND ROADSIDE CULVERTS. THE HEAVY RAINS COULD 
ALSO TRIGGER ROCK SLIDES OR DEBRIS FLOWS IN THE HIGH PARK BURN AREA.

TO REPORT ANY FLOODING TO THE NEAREST LAW ENFORCEMENT AGENCY RELAY 
YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST OFFICE IN 
DENVER.

&&

LAT...LON 4067 10552 4072 10532 4060 10531 4058 10552

$$
3 follow-up statements
249 
WGUS75 KBOU 271925
FFSBOU

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
125 PM MDT FRI JUL 27 2012

COC069-272200-
/O.CON.KBOU.FF.W.0022.000000T0000Z-120727T2200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
LARIMER CO-
125 PM MDT FRI JUL 27 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 400 PM MDT FOR
CENTRAL LARIMER COUNTY...

AT 122 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED VERY
HEAVY RAIN FROM A THUNDERSTORM 2 MILES NORTHEAST OF MISHOWAKA...OR
ABOUT 17 MILES NORTHWEST OF FORT COLLINS. THIS STORM WAS MOVING
NORTHEAST AT 10 MPH.

LOCATIONS REMAINING IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO 
MISHOWAKA AND BUCKHORN MOUNTAIN AS WELL AS THE WESTERN HALF OF THE 
HIGH PARK BURN AREA.

DOPPLER RADAR ESTIMATES THAT RAIN FROM THE STORM IS FALLING AT THE 
RATE OF ONE INCH PER HOUR.

THIS INCLUDES THE FOLLOWING STREAMS AND DRAINAGES...
CACHE LA POUDRE RIVER...SOUTH FORK CACHE LA POUDRE RIVER...
PENDERGRASS CREEK...PENNOCK CREEK...BENNETT CREEK...GORDON CREEK...
REDSTONE CREEK AND BUCKHORN CREEK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM THIS STORM WILL CAUSE FLASH FLOODING OF CREEKS
AND STREAMS...ROADS...AND ROADSIDE CULVERTS. THE HEAVY RAINS COULD 
ALSO TRIGGER DEBRIS FLOWS OR ROCK SLIDES IN THE WESTERN HALF OF THE 
HIGH PARK BURN AREA.

&&

LAT...LON 4067 10552 4072 10532 4060 10531 4058 10552

$$
011 
WGUS75 KBOU 272005
FFSBOU

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
205 PM MDT FRI JUL 27 2012

COC069-272200-
/O.CON.KBOU.FF.W.0022.000000T0000Z-120727T2200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
LARIMER CO-
205 PM MDT FRI JUL 27 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 400 PM MDT FOR
CENTRAL LARIMER COUNTY...

AT 150 PM MDT...THE LARIMER COUNTY EMERGENCY MANAGER REPORTED THE 
EASTBOUND LANE OF HIGHWAY 14 AT MILE MARKER 106...ABOUT 2 MILES EAST 
OF MISHOWAKA...WAS COMPLETELY BLOCKED BY DEBRIS. MISHOWAKA IS ABOUT 
16 MILES NORTHWEST OF FORT COLLINS.  THE STORMS WERE MOVING 
NORTHEAST AT 10 MPH.

LOCATIONS REMAINING IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO 
MISHOWAKA...BUCKHORN MOUNTAIN AND THE WESTERN HALF OF THE HIGH PARK 
BURN AREA.

DOPPLER RADAR ESTIMATES THAT 1 TO 1.25 INCHES OF RAIN HAS FALLEN IN 
THE LAST 60 MINUTES...HEAVIEST SOUTH AND EAST OF MISHOWAKA...IN THE 
THE HIGH PARK BURN AREA.  


THIS INCLUDES THE FOLLOWING STREAMS AND DRAINAGES...
CACHE LA POUDRE RIVER...SOUTH FORK CACHE LA POUDRE RIVER...
PENDERGRASS CREEK...PENNOCK CREEK...BENNETT CREEK...GORDON CREEK...
REDSTONE CREEK AND BUCKHORN CREEK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM THIS STORM WILL CAUSE FLASH FLOODING OF CREEKS
AND STREAMS...ROADS...AND ROADSIDE CULVERTS. THE HEAVY RAINS COULD 
ALSO TRIGGER DEBRIS FLOWS OR ROCK SLIDES IN THE HIGH PARK BURN AREA.

EXCESSIVE RUNOFF FROM THIS STORM WILL CAUSE FLASH FLOODING OF CREEKS
AND STREAMS...ROADS AND ROADSIDE CULVERTS. THE HEAVY RAINS COULD ALSO
TRIGGER ROCK SLIDES OR DEBRIS FLOWS IN STEEP TERRAIN.

&&

LAT...LON 4067 10552 4072 10532 4060 10531 4058 10552

$$
149 
WGUS75 KBOU 272155
FFSBOU

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
355 PM MDT FRI JUL 27 2012

COC069-272205-
/O.EXP.KBOU.FF.W.0022.000000T0000Z-120727T2200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
LARIMER CO-
355 PM MDT FRI JUL 27 2012

...THE FLASH FLOOD WARNING WILL EXPIRE AT 400 PM MDT FOR CENTRAL
LARIMER COUNTY...

THE STORMS THAT PROMPTED THE WARNING HAS EXITED THE AREA.  THEREFORE 
THE FLASH FLOOD WARNING WILL BE ALLOWED TO EXPIRE.

LAT...LON 4067 10552 4072 10532 4060 10531 4058 10552

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 27, 12:07 PM MDTAreal Flood AdvisoryBOUBoulder21 min
Jul 27, 12:38 PM MDTAreal Flood AdvisoryBOULarimer82 min

Nearby

Flash Flood Warnings in Colorado, 2012Every flash flood warning in 2012

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.