Alert archive / Colorado / Flash Flood Warnings in 2021
Flash Flood Warning 50, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this flash flood warning at Jul 30, 2021, 4:28 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 30, 2021, 4:28 PM MDT (22:28 UTC)
- Expired
- Jul 30, 2021, 7:30 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), 152 km from the middle of the area, began a volume at 22:28 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, 10.5 hours before the alert went out and 215 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
- 28 J/kg
- Mixed-layer CIN
- -252 J/kg
- Mixed-layer LCL
- 1537 m above ground
- 0-6 km bulk shear
- 15 kt
- 0-1 km storm-relative helicity
- 16 m²/s²
- 0-3 km storm-relative helicity
- 101 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.0
The text
As transmitted.
330
WGUS55 KBOU 302228
FFWBOU
COC093-310130-
/O.NEW.KBOU.FF.W.0050.210730T2228Z-210731T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Denver CO
428 PM MDT Fri Jul 30 2021
The National Weather Service in Denver has issued a
* Flash Flood Warning for...
Southwestern Park County in central Colorado...
* Until 730 PM MDT.
* At 428 PM MDT, Doppler radar indicated thunderstorms producing
heavy rain across the warned area. Between 0.5 and 1 inch of rain
has fallen. Additional rainfall amounts of 0.2 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...
mainly rural areas of Southwestern Park County
Heavy rainfall will cause flash flooding of small creaks, streams,
and ditches in the Weston Pass burn area.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
&&
LAT...LON 3904 10608 3906 10608 3909 10603 3908 10597
3901 10590 3900 10592 3897 10597 3896 10603
3899 10607
FLASH FLOOD...RADAR INDICATED
$$
Danielson2 follow-up statements
440
WGUS75 KBOU 302309
FFSBOU
Flash Flood Statement
National Weather Service Denver CO
509 PM MDT Fri Jul 30 2021
COC093-310130-
/O.CON.KBOU.FF.W.0050.000000T0000Z-210731T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Park CO-
509 PM MDT Fri Jul 30 2021
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 730 PM MDT THIS
EVENING FOR SOUTHWESTERN PARK COUNTY...
At 509 PM MDT, Doppler radar indicated thunderstorms continued
producing heavy rain in the southern part of the Weston Pass burn
scar. Between 1 and 2 inches of rain has fallen in the southern part
of the burn scar. Additional rainfall amounts of 0.2 to 1 inch are
possible in the warned area.
HAZARD...Flash flooding caused by thunderstorms.
SOURCE...Radar.
IMPACT...Flash flooding of small creeks and streams, gulches,
roads, and poor drainage and low-lying areas.
Some locations that will experience flash flooding include...
mainly rural areas of Southwestern Park County
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
&&
LAT...LON 3904 10608 3906 10608 3909 10603 3908 10597
3901 10590 3900 10592 3897 10597 3896 10603
3899 10607
FLASH FLOOD...RADAR INDICATED
$$
TH526
WGUS75 KBOU 310123
FFSBOU
Flash Flood Statement
National Weather Service Denver CO
723 PM MDT Fri Jul 30 2021
COC093-310133-
/O.EXP.KBOU.FF.W.0050.000000T0000Z-210731T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Park CO-
723 PM MDT Fri Jul 30 2021
...FLASH FLOOD WARNING WILL EXPIRE AT 730 PM MDT THIS EVENING FOR
SOUTHWESTERN PARK COUNTY...
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 Saturday for
Portions of central and north central Colorado.
LAT...LON 3904 10608 3906 10608 3909 10603 3908 10597
3901 10590 3900 10592 3897 10597 3896 10603
3899 10607
$$
DanielsonThe office that day
Everything else NWS Denver/Boulder, CO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 29, 6:37 PM MDT | Areal Flood Advisory | BOU | Grand | 83 min |
| Jul 29, 7:27 PM MDT | Areal Flood Advisory | BOU | Grand | 93 min |
| Jul 29, 7:50 PM MDT | Flash Flood Warning | BOU | Jackson, Larimer | 3 hr |
| Jul 29, 8:14 PM MDT | Flash Flood Warning | BOU | Grand | 112 min |
| Jul 29, 9:32 PM MDT | Special Weather Statement | BOU | Jackson | 28 min |
| Jul 29, 10:19 PM MDT | Areal Flood Advisory | BOU | Larimer | 86 min |
| Jul 30, 1:01 PM MDT | Flash Flood Warning | BOU | Larimer | 7 hr |
| Jul 30, 1:08 PM MDT | Areal Flood Advisory | BOU | Larimer | 6 min |
| Jul 30, 1:14 PM MDT | Flash Flood Warning | BOU | Larimer | 3 hr |
| Jul 30, 1:34 PM MDT | Flash Flood Warning | BOU | Larimer | 6 hr |
| Jul 30, 2:07 PM MDT | Flash Flood Warning | BOU | Larimer | 5 hr |
| Jul 30, 2:30 PM MDT | Flash Flood Warning | BOU | Clear Creek, Grand | 3 hr |
| Jul 30, 2:48 PM MDT | Areal Flood Advisory | BOU | Larimer | 87 min |
| Jul 30, 2:51 PM MDT | Flash Flood Warning | BOU | Grand | 4 hr |
| Jul 30, 3:02 PM MDT | Flash Flood Warning | BOU | Grand | 3 hr |
| Jul 30, 3:02 PM MDT | Special Weather Statement | BOU | Larimer | 43 min |
| Jul 30, 3:26 PM MDT | Severe Thunderstorm Warning | BOU | Larimer, Weld | 49 min |
| Jul 30, 3:45 PM MDT | Areal Flood Advisory | BOU | Grand | 2 hr |
| Jul 30, 3:59 PM MDT | Areal Flood Advisory | BOU | Larimer, Weld | 61 min |
| Jul 30, 4:11 PM MDT | Severe Thunderstorm Warning | BOU | Larimer, Weld | 49 min |
| Jul 30, 4:16 PM MDT | Flash Flood Warning | BOU | Grand | 3 hr |
| Jul 30, 4:30 PM MDT | Flash Flood Warning | BOU | Larimer | 4 hr |
| Jul 30, 5:36 PM MDT | Flash Flood Warning | BOU | Larimer | 3 hr |
| Jul 30, 5:37 PM MDT | Flash Flood Warning | BOU | Grand | 99 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.