Alert archive / Colorado / Flash Flood Warnings in 2023
Flash Flood Warning 21, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this flash flood warning at Jun 11, 2023, 5:44 PM MDT for Grand 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
- Jun 11, 2023, 5:44 PM MDT (23:44 UTC)
- Expired
- Jun 11, 2023, 8:45 PM MDT
- In force
- 3 hr
- Issued by
- NWS Denver/Boulder, CO
- Area
- Storm-based polygon
- Flood severity
- None
County Grand County, CO
The radar
The Denver radar (KFTG), 131 km from the middle of the area, began a volume at 23:48 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
Grand Junction, CO (KGJT), launched 12:00Z, 11.7 hours before the alert went out and 246 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
- 2608 m above ground
- 0-6 km bulk shear
- 27 kt
- 0-1 km storm-relative helicity
- 19 m²/s²
- 0-3 km storm-relative helicity
- 38 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
709
WGUS55 KBOU 112344
FFWBOU
COC049-120245-
/O.NEW.KBOU.FF.W.0021.230611T2344Z-230612T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Denver CO
544 PM MDT Sun Jun 11 2023
The National Weather Service in Denver has issued a
* Flash Flood Warning for...
The East Troublesome burn scar in...
Northeastern Grand County in north central Colorado...
* Until 845 PM MDT.
* At 544 PM MDT, Doppler radar indicated thunderstorms producing
heavy rain over the East Troublesome Burn Scar. Up to 0.5 inches
of rain have fallen. Additional rainfall amounts up to 0.5 inches
are possible in the warned area. Flash flooding is ongoing or
expected to begin shortly.
HAZARD...Flash flooding caused by thunderstorms in and around
the East Troublesome Burn Scar.
SOURCE...Radar.
IMPACT...Flooding of areas in and around the East Troublesome
Burn Scar.
* Some locations that will experience flash flooding include...
portions of Highway 125, and rural areas of Northeastern Grand
County
This includes the following additional locations...
Lower Stillwater Creek, Stillwater Pass, Middle Willow Creek Valley,
Lower Willow Creek Valley, Drowsy Water Ranch and Elk Mountain.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Move to higher ground now. Act quickly to protect your life.
Heavy Rainfall will cause flash flooding of small creeks, streams,
and ditches in the East Troublesome burn area. Rock slides or debris
flows can also be expected across rural roads.
&&
LAT...LON 4014 10618 4010 10614 4010 10597 4012 10591
4016 10589 4020 10589 4022 10586 4024 10585
4033 10587 4034 10596 4025 10612
FLASH FLOOD...RADAR INDICATED
$$
Hiris2 follow-up statements
665
WGUS75 KBOU 120112 RRA
FFSBOU
Flash Flood Statement
National Weather Service Denver CO
712 PM MDT Sun Jun 11 2023
COC049-120245-
/O.CON.KBOU.FF.W.0021.000000T0000Z-230612T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Grand CO-
712 PM MDT Sun Jun 11 2023
...FLASH FLOOD WARNING FOR THE EAST TROUBLESOME BURN SCAR REMAINS IN
EFFECT UNTIL 845 PM MDT THIS EVENING FOR NORTHEASTERN GRAND COUNTY...
At 712 PM MDT, Doppler radar indicated rain had ended over the East
Troublesome Burn Scar. Up to 0.5 inches of rain may have fallen.
Flash flooding is ongoing or expected to begin shortly.
HAZARD...Flash flooding caused by thunderstorms in and around the
East Troublesome Burn Scar.
SOURCE...Radar.
IMPACT...Flooding of areas in and around the East Troublesome
Burn Scar.
Some locations that will experience flash flooding include...
mainly rural areas of Northeastern Grand County
This includes the following additional locations...
rising water in the Colorado River along River Rd, Lower Stillwater
Creek, Stillwater Pass, Middle Willow Creek Valley, Lower Willow
Creek Valley, Drowsy Water Ranch and Elk Mountain.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Move to higher ground now. Act quickly to protect your life.
Heavy Rainfall will cause flash flooding of small creeks, streams,
and ditches in the East Troublesome burn area. Rock slides or debris
flows can also be expected across rural roads.
&&
LAT...LON 4014 10618 4010 10614 4010 10597 4012 10591
4016 10589 4020 10589 4022 10586 4024 10585
4033 10587 4034 10596 4025 10612
FLASH FLOOD...RADAR INDICATED
$$
RPK175
WGUS75 KBOU 120240
FFSBOU
Flash Flood Statement
National Weather Service Denver CO
840 PM MDT Sun Jun 11 2023
COC049-120250-
/O.EXP.KBOU.FF.W.0021.000000T0000Z-230612T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Grand CO-
840 PM MDT Sun Jun 11 2023
...FLASH FLOOD WARNING FOR THE EAST TROUBLESOME BURN SCAR WILL
EXPIRE AT 845 PM MDT THIS EVENING FOR NORTHEASTERN GRAND COUNTY...
Flood waters have receded. The heavy rain has ended. Flooding is no
longer expected to pose a threat. Please continue to heed remaining
road closures.
LAT...LON 4014 10618 4010 10614 4010 10597 4012 10591
4016 10589 4020 10589 4022 10586 4024 10585
4033 10587 4034 10596 4025 10612
$$
RPKThe office that day
Everything else NWS Denver/Boulder, CO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 11, 11:43 AM MDT | Flood Watch | BOU | Adams, Arapahoe, Boulder, Broomfield, Clear Creek, Denver and 6 more | 15 hr |
| Jun 11, 3:13 PM MDT | Special Weather Statement | BOU | Denver | 32 min |
| Jun 11, 3:20 PM MDT | Severe Thunderstorm Warning | BOU | Douglas | 29 min |
| Jun 11, 3:25 PM MDT | Severe Thunderstorm Warning | BOU | Douglas | 50 min |
| Jun 11, 3:31 PM MDT | Areal Flood Advisory | BOU | Douglas | 2 hr |
| Jun 11, 4:04 PM MDT | Flash Flood Warning | BOU | Larimer | 3 hr |
| Jun 11, 4:08 PM MDT | Special Weather Statement | BOU | Arapahoe | 52 min |
| Jun 11, 4:23 PM MDT | Flash Flood Warning | BOU | Park | 3 hr |
Nearby
Flash Flood Warnings in Colorado, 2023Every flash flood warning in 2023
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.