Alert archive / Colorado / Flash Flood Warnings in 2013

Flash Flood Warning 49, NWS Denver/Boulder, CO

September 12, 2013Boulder County, Colorado

NWS Denver/Boulder, CO issued this flash flood warning at Sep 12, 2013, 8:36 AM 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
Sep 12, 2013, 8:36 AM MDT (14:36 UTC)
Expired
Sep 12, 2013, 11:30 AM 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), 73 km from the middle of the area, began a volume at 14:39 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 12:00Z, 2.6 hours before the alert went out and 180 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 2013-09-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 156 joules per kilogram.LCLLFCEL10008507005003002001001 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 2013-09-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 15 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
156 J/kg
Mixed-layer CIN
-28 J/kg
Mixed-layer LCL
555 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
15 m²/s²
0-3 km storm-relative helicity
-38 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.

586 
WGUS55 KBOU 121436
FFWBOU
COC013-121730-
/O.NEW.KBOU.FF.W.0049.130912T1436Z-130912T1730Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE DENVER CO
836 AM MDT THU SEP 12 2013

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A

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

* UNTIL 1130 AM MDT

* AT 834 AM MDT...DOPPLER RADAR INDICATED HEAVY RAIN ACROSS THE  
  FOURMILE BURN AREA. UP TO ONE INCH OF RAIN MAY FALL IN THE NEXT 
  45 MINUTES. FLASH FLOODING IS EXPECTED TO BEGIN SHORTLY.

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

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.

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.

STAY AWAY OR BE SWEPT AWAY. RIVER BANKS AND CULVERTS CAN BECOME
UNSTABLE AND UNSAFE.

&&

LAT...LON 4009 10527 3999 10526 3999 10544 4009 10543

$$

RPK

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 11, 6:36 PM MDTFlash Flood WarningBOUBoulder, Broomfield, Weld3 hr
Sep 11, 7:02 PM MDTFlash Flood WarningBOUBoulder3 hr
Sep 11, 7:23 PM MDTAreal Flood AdvisoryBOULarimer, Weld3 hr
Sep 11, 7:58 PM MDTFlash Flood WarningBOUAdams, Boulder, Broomfield, Weld3 hr
Sep 11, 8:25 PM MDTFlash Flood WarningBOULarimer3 hr
Sep 11, 8:28 PM MDTAreal Flood AdvisoryBOULarimer2 hr
Sep 11, 8:31 PM MDTAreal Flood AdvisoryBOUWashington119 min
Sep 11, 9:46 PM MDTFlash Flood WarningBOUBoulder, Jefferson3 hr
Sep 11, 9:47 PM MDTAreal Flood AdvisoryBOUArapahoe, Denver3 hr
Sep 11, 9:53 PM MDTAreal Flood WarningBOUAdams, Weld3 hr
Sep 11, 10:01 PM MDTFlash Flood WarningBOUAdams, Arapahoe, Denver3 hr
Sep 11, 10:16 PM MDTAreal Flood AdvisoryBOULarimer, Weld3 hr
Sep 11, 10:28 PM MDTAreal Flood AdvisoryBOULarimer3 hr
Sep 11, 10:49 PM MDTFlash Flood WarningBOULarimer5 hr
Sep 11, 11:16 PM MDTFlash Flood Warning EmergencyBOUBoulder, Jefferson5 hr
Sep 11, 11:42 PM MDTFlash Flood WarningBOUBroomfield3 hr
Sep 12, 12:02 AM MDTRiver Flood WarningBOUBoulder6 hr
Sep 12, 12:02 AM MDTRiver Flood WarningBOUBoulder2 hr
Sep 12, 12:02 AM MDTRiver Flood WarningBOUBoulder17 hr
Sep 12, 12:31 AM MDTFlash Flood WarningBOULarimer, Weld4 hr
Sep 12, 12:37 AM MDTAreal Flood AdvisoryBOUAdams, Weld3 hr
Sep 12, 12:59 AM MDTAreal Flood WarningBOUAdams, Arapahoe, Denver3 hr
Sep 12, 2:04 AM MDTFlash Flood WarningBOUWeld3 hr
Sep 12, 2:34 AM MDTFlash Flood WarningBOULarimer3 hr
Sep 12, 2:50 AM MDTAreal Flood AdvisoryBOUAdams3 hr
Sep 12, 3:07 AM MDTFlash Flood Warning EmergencyBOUWeld4 hr
Sep 12, 4:10 AM MDTFlash Flood WarningBOUBoulder3 hr
Sep 12, 4:18 AM MDTFlash Flood WarningBOULarimer3 hr
Sep 12, 4:20 AM MDTFlash Flood Warning EmergencyBOUAdams3 hr
Sep 12, 4:36 AM MDTRiver Flood AdvisoryBOULarimer6 hr
Sep 12, 5:00 AM MDTFlash Flood WatchBOUAdams, Arapahoe, Boulder, Broomfield, Clear Creek, Denver and 7 more40 hr
Sep 12, 5:24 AM MDTAreal Flood AdvisoryBOUAdams, Denver3 hr
Sep 12, 5:59 AM MDTAreal Flood WarningBOULarimer9 hr
Sep 12, 6:01 AM MDTFlash Flood WarningBOUAdams, Denver3 hr
Sep 12, 6:09 AM MDTRiver Flood WarningBOUAdams20 hr
Sep 12, 6:09 AM MDTRiver Flood WarningBOUWeld9 days
Sep 12, 6:09 AM MDTRiver Flood WarningBOUMorgan6 days
Sep 12, 6:09 AM MDTRiver Flood WarningBOULogan, Morgan, Washington8 days
Sep 12, 6:19 AM MDTRiver Flood WarningBOULarimer14 hr
Sep 12, 6:52 AM MDTFlash Flood WarningBOUWeld3 hr
Sep 12, 6:55 AM MDTFlash Flood WarningBOUAdams3 hr
Sep 12, 7:05 AM MDTFlash Flood WarningBOULarimer3 hr
Sep 12, 7:06 AM MDTRiver Flood WarningBOULarimer5 days
Sep 12, 7:12 AM MDTFlash Flood WarningBOUBoulder3 hr
Sep 12, 7:24 AM MDTFlash Flood WarningBOUArapahoe3 hr
Sep 12, 7:32 AM MDTAreal Flood AdvisoryBOUArapahoe3 hr
Sep 12, 8:28 AM MDTAreal Flood WarningBOUAdams, Arapahoe, Boulder, Broomfield, Denver, Jefferson and 2 more12 hr
Sep 12, 9:02 AM MDTFlash Flood WarningBOUAdams, Arapahoe, Denver3 hr
Sep 12, 9:12 AM MDTFlash Flood WarningBOUArapahoe, Denver3 hr
Sep 12, 9:51 AM MDTFlash Flood WarningBOULarimer3 hr
Sep 12, 10:02 AM MDTFlash Flood WarningBOUBoulder3 hr
Sep 12, 10:44 AM MDTFlash Flood WarningBOULarimer3 hr
Sep 12, 10:58 AM MDTRiver Flood WarningBOUWeld6 days
Sep 12, 12:04 PM MDTRiver Flood WarningBOUBoulder19 hr
Sep 12, 12:14 PM MDTFlash Flood WarningBOUAdams, Arapahoe, Denver3 hr
Sep 12, 12:35 PM MDTFlash Flood WarningBOULarimer9 hr
Sep 12, 1:42 PM MDTFlash Flood WarningBOULarimer3 hr
Sep 12, 3:13 PM MDTAreal Flood AdvisoryBOUArapahoe, Elbert3 hr
Sep 12, 3:29 PM MDTFlash Flood Warning EmergencyBOUBoulder, Jefferson8 hr
Sep 12, 4:35 PM MDTRiver Flood WarningBOULarimer4 hr
Sep 12, 4:35 PM MDTRiver Flood WarningBOULarimer4 hr
Sep 12, 5:04 PM MDTFlash Flood WarningBOUArapahoe, Denver, Douglas4 hr

Nearby

Flash Flood Warnings in Colorado, 2013Every flash flood warning in 2013

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.