Alert archive / Colorado / Flash Flood Warnings in 2011
Flash Flood Warning 34, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this flash flood warning at Aug 2, 2011, 2:13 PM MDT for Douglas County, Jefferson County, Colorado. It was in force for 91 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 2, 2011, 2:13 PM MDT (20:13 UTC)
- Expired
- Aug 2, 2011, 3:44 PM MDT
- In force
- 91 min
- Issued by
- NWS Denver/Boulder, CO
- Area
- Storm-based polygon
- Flood severity
- None
Counties Douglas County, CO, Jefferson County, CO
The radar
The Denver radar (KFTG), 73 km from the middle of the area, began a volume at 20:13 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, 8.2 hours before the alert went out and 177 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1845 m above ground
- 0-6 km bulk shear
- 25 kt
- 0-1 km storm-relative helicity
- 2 m²/s²
- 0-3 km storm-relative helicity
- 102 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
462
WGUS55 KBOU 022013
FFWBOU
COC035-059-022315-
/O.NEW.KBOU.FF.W.0034.110802T2013Z-110802T2315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE DENVER CO
213 PM MDT TUE AUG 2 2011
THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A
* FLASH FLOOD WARNING FOR...
SOUTHEASTERN JEFFERSON COUNTY IN NORTHEAST COLORADO
WESTERN DOUGLAS COUNTY IN NORTHEAST COLORADO
* UNTIL 515 PM MDT
* AT 211 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
VERY HEAVY RAIN FROM A LINE OF THUNDERSTORM ALONG THE SOUTH PLATTE
RIVER SOUTHWEST OF DENVER. THE HEAVIEST RAINFALL WAS INDICATED 3
MILES SOUTH OF SOUTH PLATTE...OR 28 MILES SOUTHWEST OF DENVER.
THESE STORMS WERE MOVING EAST AT 10 MPH.
* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO DEVILS
HEAD...WESTCREEK...SPRUCEWOOD...SOUTH PLATTE...SEDALIA...ROXBOROUGH
PARK...LOUVIERS...DECKERS...CHEESMAN RESERVOIR AND BUFFALO CREEK.
DOPPLER RADAR ESTIMATES THAT AROUND 1.5 INCHES OF RAIN HAS FALLEN
FROM THIS STORM IN THE LAST 40 MINUTES.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
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.
DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY AS THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO
CROSS SAFELY. DO NOT UNDERESTIMATE THE POWER OF FLOOD WATERS. ONLY A
FEW INCHES OF RAPIDLY FLOWING WATER CAN QUICKLY CARRY AWAY YOUR
VEHICLE. TURN AROUND...DO NOT DROWN.
&&
LAT...LON 3937 10528 3951 10520 3953 10487 3914 10506
3913 10538
$$
BAKER1 follow-up statement
643
WGUS75 KBOU 022144
FFSBOU
FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
344 PM MDT TUE AUG 2 2011
COC035-059-022151-
/O.CAN.KBOU.FF.W.0034.000000T0000Z-110802T2315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
JEFFERSON CO-DOUGLAS CO-
344 PM MDT TUE AUG 2 2011
...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR WESTERN DOUGLAS AND
SOUTHEASTERN JEFFERSON COUNTIES...
THE STORMS THAT PROMPTED THE WARNING HAVE WEAKENED AND WERE NO
LONGER PRODUCING HEAVY RAINFALL. THEREFORE THE RISK OF FLASH
FLOODING HAS ENDED FOR NOW.
EARLIER THIS AFTERNOON THUNDERSTORMS OVER SOUTHEAST JEFFERSON AND
WEST CENTRAL DOUGLAS COUNTIES NEAR THE TOWNS OF DECKERS...BUFFALO
CREEK AND SOUTH PLATTE PRODUCED HEAVY RAINFALL THAT REPORTEDLY
CAUSED MINOR FLOODING ON SMALL STREAMS...CREEKS AND GULLIES IN THE
AREA. THE HEAVIEST RAINFALL INDICATED ON WEATHER SERVICE DOPPLER
RADAR OCCURRED APPROXIMATELY 5 MILES SOUTH OF BUFFALO CREEK WHERE
AN ESTIMATED 1.5 TO 2 INCHES OF RAIN FELL IN ABOUT AN HOUR.
LAT...LON 3937 10528 3951 10520 3953 10487 3914 10506
3913 10538
$$
BAKERThe office that day
Everything else NWS Denver/Boulder, CO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 2, 4:17 AM MDT | Flash Flood Watch | BOU | Arapahoe, Boulder, Clear Creek, Douglas, Elbert, Gilpin and 5 more | 16 hr |
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.