Alert archive / Colorado / Flash Flood Warnings in 2021
Flash Flood Warning 60, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this flash flood warning at Jul 31, 2021, 3:33 PM MDT for Park 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
- Jul 31, 2021, 3:33 PM MDT (21:33 UTC)
- Expired
- Jul 31, 2021, 6:45 PM MDT
- In force
- 3 hr
- Issued by
- NWS Denver/Boulder, CO
- Area
- Storm-based polygon
- Flood severity
- None
County Park County, CO
The radar
The Denver radar (KFTG), 134 km from the middle of the area, began a volume at 21:35 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, 9.6 hours before the alert went out and 222 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
- 1449 m above ground
- 0-6 km bulk shear
- 4 kt
- 0-1 km storm-relative helicity
- 66 m²/s²
- 0-3 km storm-relative helicity
- 112 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
811
WGUS55 KBOU 312133
FFWBOU
COC093-010045-
/O.NEW.KBOU.FF.W.0060.210731T2133Z-210801T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Denver CO
333 PM MDT Sat Jul 31 2021
The National Weather Service in Denver has issued a
* Flash Flood Warning for...
West Central Park County in central Colorado...
* Until 645 PM MDT.
* At 333 PM MDT, Doppler radar indicated thunderstorms producing
heavy rain across the warned area. Between 1.5 and 2.5 inches of
rain have fallen. Additional rainfall amounts up to 1 inch are
possible in the warned area. Flash flooding is ongoing or expected
to begin shortly.
HAZARD...Flash flooding caused by thunderstorms.
SOURCE...Radar.
IMPACT...Flash flooding of small creeks and streams, gulches,
roads, and poor drainage and low-lying areas.
* Some locations that will experience flash flooding include...
Fairplay, Red Hill Pass, Como and Garo.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Move to higher ground now. Act quickly to protect your life.
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.
&&
LAT...LON 3931 10597 3932 10584 3926 10577 3913 10582
3911 10595 3916 10602 3923 10604 3929 10600
FLASH FLOOD...RADAR INDICATED
$$
RPK2 follow-up statements
440
WGUS75 KBOU 312229
FFSBOU
Flash Flood Statement
National Weather Service Denver CO
429 PM MDT Sat Jul 31 2021
COC093-010045-
/O.CON.KBOU.FF.W.0060.000000T0000Z-210801T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Park CO-
429 PM MDT Sat Jul 31 2021
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 645 PM MDT THIS
EVENING FOR WEST CENTRAL PARK COUNTY...
At 429 PM MDT, Doppler radar indicated thunderstorms producing heavy
rain across the warned area. Between 2 and 3 inches of rain have
fallen. Additional rainfall amounts up to 0.50 inches are possible
in the warned area. Flash flooding is ongoing or expected to begin
shortly.
HAZARD...Flash flooding caused by thunderstorms.
SOURCE...Radar.
IMPACT...Flash flooding of small creeks and streams, gulches,
roads, and poor drainage and low-lying areas.
Some locations that will experience flash flooding include...
Fairplay, Red Hill Pass, Como and Garo.
This includes the following streams and drainages...
Fourmile Creek, Crooked Creek, Park Gulch, Middle Fork South
Platte River, Tarryall Creek, Sacramento Creek, Trout Creek and
Ruby Gulch.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Move to higher ground now. Act quickly to protect your life.
Excessive runoff from this storm will cause flash flooding of creeks
and streams, roads and roadside culverts. The heavy rains could also
trigger rock slides or debris flows in steep terrain.
&&
LAT...LON 3931 10597 3932 10584 3926 10577 3913 10582
3911 10595 3916 10602 3923 10604 3929 10600
FLASH FLOOD...RADAR INDICATED
$$
RPK221
WGUS75 KBOU 010037
FFSBOU
Flash Flood Statement
National Weather Service Denver CO
637 PM MDT Sat Jul 31 2021
COC093-010047-
/O.EXP.KBOU.FF.W.0060.000000T0000Z-210801T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Park CO-
637 PM MDT Sat Jul 31 2021
...FLASH FLOOD WARNING WILL EXPIRE AT 645 PM MDT THIS EVENING FOR
WEST CENTRAL PARK 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.
A Flash Flood Watch remains in effect until 900 PM MDT for Portions
of central, north central, and northeast Colorado.
LAT...LON 3931 10597 3932 10584 3926 10577 3913 10582
3911 10595 3916 10602 3923 10604 3929 10600
$$
RPKThe office that day
Everything else NWS Denver/Boulder, CO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 30, 6:01 PM MDT | Areal Flood Advisory | BOU | Boulder, Broomfield, Weld | 59 min |
| Jul 30, 6:08 PM MDT | Areal Flood Advisory | BOU | Adams, Denver | 82 min |
| Jul 30, 6:48 PM MDT | Areal Flood Advisory | BOU | Douglas, Elbert | 117 min |
| Jul 30, 7:13 PM MDT | Areal Flood Warning | BOU | Larimer | 3 hr |
| Jul 30, 7:35 PM MDT | Areal Flood Advisory | BOU | Boulder | 70 min |
| Jul 30, 7:52 PM MDT | Areal Flood Advisory | BOU | Boulder, Broomfield, Weld | 83 min |
| Jul 30, 7:53 PM MDT | Areal Flood Advisory | BOU | Larimer | 68 min |
| Jul 30, 8:19 PM MDT | Areal Flood Advisory | BOU | Douglas, Jefferson | 42 min |
| Jul 30, 9:34 PM MDT | Areal Flood Advisory | BOU | Adams, Boulder, Broomfield, Denver, Jefferson, Weld | 56 min |
| Jul 30, 9:35 PM MDT | Areal Flood Advisory | BOU | Clear Creek, Gilpin | 3 hr |
| Jul 30, 10:18 PM MDT | Flash Flood Warning | BOU | Boulder, Broomfield, Weld | 3 hr |
| Jul 30, 11:17 PM MDT | Special Weather Statement | BOU | Weld | 28 min |
| Jul 30, 11:24 PM MDT | Areal Flood Advisory | BOU | Weld | 81 min |
| Jul 30, 11:40 PM MDT | Areal Flood Advisory | BOU | Weld | 60 min |
| Jul 31, 1:12 AM MDT | Special Weather Statement | BOU | Logan | 33 min |
| Jul 31, 2:39 AM MDT | Special Weather Statement | BOU | Logan | 51 min |
| Jul 31, 3:20 AM MDT | Special Weather Statement | BOU | Phillips, Sedgwick | 40 min |
| Jul 31, 3:59 AM MDT | Areal Flood Advisory | BOU | Logan, Phillips, Sedgwick | 74 min |
| Jul 31, 11:49 AM MDT | Flash Flood Warning | BOU | Larimer | 2 hr |
| Jul 31, 12:27 PM MDT | Flash Flood Warning | BOU | Grand | 3 hr |
| Jul 31, 12:29 PM MDT | Areal Flood Advisory | BOU | Grand | 91 min |
| Jul 31, 12:32 PM MDT | Areal Flood Advisory | BOU | Grand | 88 min |
| Jul 31, 12:34 PM MDT | Areal Flood Advisory | BOU | Grand | 86 min |
| Jul 31, 12:39 PM MDT | Areal Flood Advisory | BOU | Park | 81 min |
| Jul 31, 12:42 PM MDT | Areal Flood Advisory | BOU | Park | 93 min |
| Jul 31, 1:05 PM MDT | Areal Flood Advisory | BOU | Larimer | 85 min |
| Jul 31, 1:33 PM MDT | Areal Flood Advisory | BOU | Grand | 87 min |
| Jul 31, 2:16 PM MDT | Flash Flood Warning | BOU | Larimer | 89 min |
| Jul 31, 2:43 PM MDT | Flash Flood Warning | BOU | Larimer | 92 min |
| Jul 31, 2:57 PM MDT | Areal Flood Advisory | BOU | Park | 93 min |
| Jul 31, 3:24 PM MDT | Flash Flood Warning | BOU | Larimer | 81 min |
| Jul 31, 3:29 PM MDT | Areal Flood Advisory | BOU | Boulder | 91 min |
| Jul 31, 3:37 PM MDT | Flash Flood Warning | BOU | Boulder | 3 hr |
| Jul 31, 3:51 PM MDT | Areal Flood Advisory | BOU | Boulder | 84 min |
| Jul 31, 4:31 PM MDT | Areal Flood Advisory | BOU | Park | 89 min |
| Jul 31, 4:42 PM MDT | Areal Flood Advisory | BOU | Park | 93 min |
| Jul 31, 4:52 PM MDT | Areal Flood Advisory | BOU | Park | 83 min |
Nearby
Flash Flood Warnings in Colorado, 2021Every flash flood warning in 2021
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.