Alert archive / Colorado / Flash Flood Warnings in 2014

Flash Flood Warning 2, NWS Denver/Boulder, CO

May 23, 2014Boulder County, Colorado

NWS Denver/Boulder, CO issued this flash flood warning at May 23, 2014, 7:20 PM MDT for Boulder 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
May 23, 2014, 7:20 PM MDT (01:20 UTC)
Expired
May 23, 2014, 10:15 PM MDT
In force
3 hr
Issued by
NWS Denver/Boulder, CO
Area
Storm-based polygon
Flood severity
None

County Boulder County, CO

The radar

The Denver radar (KFTG), 75 km from the middle of the area, began a volume at 01:19 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 (KDEN), launched 00:00Z, 1.3 hours before the alert went out and 183 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 00:00Z on 2014-05-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 530 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Denver, CO at 00:00Z on 2014-05-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -72 square meters per square second.19395878Sfc1 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
530 J/kg
Mixed-layer CIN
-48 J/kg
Mixed-layer LCL
1524 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
-72 m²/s²
0-3 km storm-relative helicity
-15 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.

645 
WGUS55 KBOU 240120
FFWBOU
COC013-240415-
/O.NEW.KBOU.FF.W.0002.140524T0120Z-140524T0415Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE DENVER CO
720 PM MDT FRI MAY 23 2014

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CENTRAL BOULDER COUNTY IN CENTRAL COLORADO...

* UNTIL 1015 PM MDT
    
* AT 718 PM MDT...DOPPLER RADAR INDICATED A THUNDERSTORM PRODUCING
  HEAVY RAIN OVER CRISMAN. THE RAIN IS MOVING NORTHWEST AT 15 MPH.
  FLASH FLOODING IS EXPECTED TO BEGIN SHORTLY. EXCESSIVE RAINFALL
  OVER THE BURN SCAR WILL RESULT IN DEBRIS FLOW MOVING THROUGH THE 
  FOUR MILE BURN AERA. THE DEBRIS FLOW CAN CONSIST OF ROCK...MUD... 
  VEGETATION AND OTHER LOOSE MATERIALS.

* SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  SUMMERVILLE...SALINA...CRISMAN...GOLD HILL...SUNSHINE AND
  WALLSTREET.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A LIFE THREATENING SITUATION.  HEAVY RAINFALL WILL CAUSE
EXTENSIVE AND SEVERE FLASH FLOODING OF CREEKS...STREAMS...AND DITCHES
IN THE FOURMILE BURN AREA. SOME DRAINAGE BASINS IMPACTED INCLUDE
FOURMILE CREEK...GOLD RUN...AND FOURMILE CANYON CREEK.  SEVERE DEBRIS
FLOWS CAN ALSO BE ANTICIPATED ACROSS ROADS.  ROADS AND DRIVEWAYS MAY
BE WASHED AWAY IN PLACES.  IF YOU ENCOUNTER FLOOD WATERS...CLIMB TO
SAFETY.

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.

MOVE TO HIGHER GROUND NOW. ACT QUICKLY TO PROTECT YOUR LIFE.

&&

LAT...LON 4000 10535 4004 10544 4009 10538 4006 10529

$$

ENTREKIN
2 follow-up statements
078 
WGUS75 KBOU 240203
FFSBOU

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
803 PM MDT FRI MAY 23 2014

COC013-240415-
/O.CON.KBOU.FF.W.0002.000000T0000Z-140524T0415Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BOULDER CO-
803 PM MDT FRI MAY 23 2014

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1015 PM MDT FOR
CENTRAL BOULDER COUNTY...

AT 758 PM MDT...A THUNDERSTORM PRODUCING HEAVY RAIN WAS LOCATED OVER
CRISMAN...OR 30 MILES NORTHWEST OF DENVER...AND IS STATIONARY.  FLASH
FLOODING IS EXPECTED TO BEGIN SHORTLY.

EXCESSIVE RAINFALL OVER THE BURN SCAR WILL RESULT IN DEBRIS FLOW 
MOVING THROUGH FOUR MILE CREEK. THE DEBRIS FLOW CAN CONSIST OF 
ROCK...MUD...VEGETATION AND OTHER LOOSE MATERIALS.

SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
SUMMERVILLE...SALINA...CRISMAN...GOLD HILL...SUNSHINE AND WALLSTREET.

SPOTTERS AND AUTOMATED RAIN GAUGES HAVE REPORTED AROUND A HALF INCH 
OF RAIN IN THE PAST 45 MINUTES. ADDITIONAL STORMS WILL CONTINUE TO 
MOVE NORTHWARD ACROSS THE BURN AREA AND CONTINUE TO CREATE FLASH 
FLOODING. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

HEAVY RAINFALL WILL CAUSE FLASH FLOODING OF CREEKS...STREAMS...AND
DITCHES IN THE FOURMILE BURN AREA.  SOME DRAINAGE BASINS AFFECTED BY
EXCESSIVE RUNOFF INCLUDE FOURMILE CREEK...GOLD RUN...AND FOURMILE
CANYON CREEK.  WATER WILL BE FLOWING DOWN ROADWAYS.  ROCK SLIDES OR
DEBRIS FLOWS CAN ALSO BE EXPECTED.

&&

LAT...LON 4000 10535 4004 10544 4009 10538 4006 10529

$$

ENTREKIN
282 
WGUS75 KBOU 240251
FFSBOU

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
851 PM MDT FRI MAY 23 2014

COC013-240258-
/O.CAN.KBOU.FF.W.0002.000000T0000Z-140524T0415Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BOULDER CO-
851 PM MDT FRI MAY 23 2014

...THE FLASH FLOOD WARNING FOR CENTRAL BOULDER COUNTY IS CANCELLED...

THE HEAVY RAIN HAS ENDED...AND FLOODING IS NO LONGER EXPECTED TO 
POSE A THREAT OVER THE FOUR MILE BURN AREA. EMERGENCY MANGERS HAVE 
REPORTED SOME DEBRIS FLOW ON THE NORTHEAST PORTIONS OF FOUR MILE 
BURN BUT NO MAJOR FLOODING PROBLEMS. 

LAT...LON 4000 10535 4004 10544 4009 10538 4006 10529

$$

ENTREKIN

The office that day

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

IssuedProductOfficeCountiesLasted
May 23, 6:05 PM MDTAreal Flood AdvisoryBOUAdams, Arapahoe, Denver115 min
May 23, 7:21 PM MDTFlash Flood WarningBOULarimer3 hr
May 23, 8:10 PM MDTFlash Flood WarningBOULarimer, Weld3 hr
May 23, 9:20 PM MDTAreal Flood AdvisoryBOUWeld4 hr
May 23, 10:06 PM MDTAreal Flood WarningBOULarimer4 hr
May 23, 10:10 PM MDTFlash Flood WarningBOUWeld3 hr
May 23, 10:26 PM MDTAreal Flood AdvisoryBOUAdams, Denver, Weld3 hr
May 23, 11:09 PM MDTAreal Flood AdvisoryBOULarimer96 min
May 24, 5:50 AM MDTFlash Flood WatchBOUAdams, Arapahoe, Boulder, Broomfield, Clear Creek, Denver and 7 more17 hr
May 24, 4:42 PM MDTSpecial Weather StatementBOUGrand33 min
May 24, 5:11 PM MDTSpecial Weather StatementBOUJackson34 min
May 24, 5:37 PM MDTSpecial Weather StatementBOUJefferson23 min
May 24, 5:58 PM MDTSpecial Weather StatementBOUDouglas47 min

Nearby

Flash Flood Warnings in Colorado, 2014Every flash flood warning in 2014

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.