Alert archive / Colorado / Flash Flood Warnings in 2011
Flash Flood Warning 35, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this flash flood warning at Aug 3, 2011, 4:59 PM MDT for Douglas County, Colorado. It was in force for 70 min. 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 3, 2011, 4:59 PM MDT (22:59 UTC)
- Expired
- Aug 3, 2011, 6:09 PM MDT
- In force
- 70 min
- Issued by
- NWS Denver/Boulder, CO
- Area
- Storm-based polygon
- Flood severity
- None
County Douglas County, CO
The radar
The Denver radar (KFTG), 87 km from the middle of the area, began a volume at 23:02 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 (KDNR), launched 12:00Z, 11.0 hours before the alert went out and 184 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.
- Mixed-layer CAPE
- 15 J/kg
- Mixed-layer CIN
- -54 J/kg
- Mixed-layer LCL
- 1190 m above ground
- 0-6 km bulk shear
- 13 kt
- 0-1 km storm-relative helicity
- -14 m²/s²
- 0-3 km storm-relative helicity
- 4 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
207 WGUS55 KBOU 032259 FFWBOU COC035-040100- /O.NEW.KBOU.FF.W.0035.110803T2259Z-110804T0100Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ BULLETIN - EAS ACTIVATION REQUESTED FLASH FLOOD WARNING NATIONAL WEATHER SERVICE DENVER CO 459 PM MDT WED AUG 3 2011 THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A * FLASH FLOOD WARNING FOR... SOUTHWESTERN DOUGLAS COUNTY IN NORTHEAST COLORADO * UNTIL 700 PM MDT * AT 457 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED VERY HEAVY RAIN FROM A THUNDERSTORM 7 MILES SOUTH OF WESTCREEK...OR 23 MILES NORTHWEST OF COLORADO SPRINGS. THIS STORM WAS MOVING NORTHEAST AT 10 MPH. * LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO WESTCREEK TRAIL CREEK. DOPPLER RADAR ESTIMATES THAT AROUND 1.5 INCHES OF RAIN HAVE FALLEN FROM THIS STORM IN THE LAST 45 MINUTES. PRECAUTIONARY/PREPAREDNESS ACTIONS... A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING. IF YOU ARE IN THE WARNING AREA MOVE TO HIGHER GROUND IMMEDIATELY. RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE IMMEDIATE PRECAUTIONS TO PROTECT LIFE AND PROPERTY. DO NOT ATTEMPT TO CROSS SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN DEPTH BY FOOT OR BY AUTOMOBILE. TURN AROUND...DO NOT DROWN. HEAVY RAINFALL WILL CAUSE FLASH FLOODING OF SMALL CREEKS...STREAMS AND DITCHES IN THE HAYMAN FIRE BURN AREA. SOME DRAINAGE BASINS AFFECTED BY EXCESSIVE RUNOFF INCLUDE FOURMILE CREEK...SIXMILE CREEK...TRAIL CREEK AND WEST CREEK. ROCK SLIDES OR DEBRIS FLOWS CAN ALSO BE EXPECTED ACROSS RURAL ROADS. && LAT...LON 3923 10518 3913 10513 3913 10514 3913 10521 $$
1 follow-up statement
562 WGUS75 KBOU 040009 FFSBOU FLASH FLOOD STATEMENT NATIONAL WEATHER SERVICE DENVER CO 609 PM MDT WED AUG 3 2011 COC035-040017- /O.CAN.KBOU.FF.W.0035.000000T0000Z-110804T0100Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ DOUGLAS CO- 609 PM MDT WED AUG 3 2011 ...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR SOUTHWESTERN DOUGLAS COUNTY... THE STORM THAT PROMPTED THE WARNING HAS EXITED THE AREA AND WATERS HAVE RECEDED. A FEW ROADS IN THE AREA HAVE HAD REPORTS OF ROCKS WASHED ONTO THEM BY THE HEAVY RAIN...USE CAUTION WHEN DRIVING. LAT...LON 3923 10518 3913 10513 3913 10514 3913 10521 $$
The office that day
Everything else NWS Denver/Boulder, CO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 2, 6:17 PM MDT | Areal Flood Advisory | BOU | Morgan, Weld | 88 min |
| Aug 2, 11:11 PM MDT | Areal Flood Advisory | BOU | Lincoln | 94 min |
| Aug 3, 1:39 PM MDT | Areal Flood Advisory | BOU | Grand | 64 min |
Nearby
Flash Flood Warnings in Colorado, 2011Every flash flood warning in 2011
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.