Alert archive / Colorado / Flash Flood Warnings in 2025
Flash Flood Warning 21, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this flash flood warning at Aug 26, 2025, 6:37 PM MDT for Arapahoe County, Elbert 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
- Aug 26, 2025, 6:37 PM MDT (00:37 UTC)
- Expired
- Aug 26, 2025, 9:30 PM MDT
- In force
- 3 hr
- Issued by
- NWS Denver/Boulder, CO
- Area
- Storm-based polygon
- Flood severity
- None
Counties Arapahoe County, CO, Elbert County, CO
The radar
The Denver radar (KFTG), 21 km from the middle of the area, began a volume at 00:38 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
Dodge City, (KDDC), launched 00:00Z, 0.6 hours before the alert went out and 455 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
- 1263 m above ground
- 0-6 km bulk shear
- 41 kt
- 0-1 km storm-relative helicity
- 33 m²/s²
- 0-3 km storm-relative helicity
- 32 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
458
WGUS55 KBOU 270037
FFWBOU
COC005-039-270330-
/O.NEW.KBOU.FF.W.0021.250827T0037Z-250827T0330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Denver CO
637 PM MDT Tue Aug 26 2025
The National Weather Service in Denver has issued a
* Flash Flood Warning for...
Northwestern Elbert County in east central Colorado...
Central Arapahoe County in northeastern Colorado...
* Until 930 PM MDT.
* At 637 PM MDT, trained weather spotters reported flooding near the
Arapahoe and Elbert county line. Between 2.5 and 3.5 inches of
rain have fallen. Additional rainfall amounts of 0.5 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...Trained spotters reported.
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...
Southern Aurora, Bennett, Arapahoe Park and Strasburg.
This includes the following streams and drainages...
Wolf Creek, East Toll Gate Creek, Piney Creek, Coal Creek, Murphy
Creek, Comanche Creek, Running Creek, West Sand Creek, Kiowa Creek
and First Creek.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Be aware of your surroundings and do not drive on flooded roads.
Please report observed flooding to local emergency services or law
enforcement and request they pass this information to the National
Weather Service when you can do so safely.
&&
LAT...LON 3957 10472 3970 10469 3971 10434 3954 10437
3954 10466 3957 10466
FLASH FLOOD...OBSERVED
$$
Ideker2 follow-up statements
006
WGUS75 KBOU 270151
FFSBOU
Flash Flood Statement
National Weather Service Denver CO
751 PM MDT Tue Aug 26 2025
COC005-039-270330-
/O.CON.KBOU.FF.W.0021.000000T0000Z-250827T0330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Arapahoe CO-Elbert CO-
751 PM MDT Tue Aug 26 2025
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 930 PM MDT THIS
EVENING FOR NORTHWESTERN ELBERT AND CENTRAL ARAPAHOE COUNTIES...
At 751 PM MDT, doppler radar and trained weather spotters reported
between 2.5 and 3.5 inches of rain had fallen earlier this evening.
Additional rainfall amounts up to 0.25 inches are possible in the
warned area. Flash flooding is ongoing or expected to begin shortly.
HAZARD...Flash flooding caused by thunderstorms.
SOURCE...Trained spotters reported.
IMPACT...Flash flooding of small creeks and streams, gulches,
roads, and poor drainage and low-lying areas.
Some locations that will experience flash flooding include...
Southern Aurora, Bennett, Arapahoe Park and Strasburg.
This includes the following streams and drainages...
Wolf Creek, East Toll Gate Creek, Piney Creek, Coal Creek, Murphy
Creek, Comanche Creek, Running Creek, West Sand Creek, Kiowa Creek
and First Creek.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Be especially cautious at night when it is harder to recognize the
dangers of flooding.
Be aware of your surroundings and do not drive on flooded roads.
&&
LAT...LON 3957 10472 3970 10469 3971 10434 3954 10437
3954 10466 3957 10466
FLASH FLOOD...OBSERVED
$$
Ideker268
WGUS75 KBOU 270323
FFSBOU
Flash Flood Statement
National Weather Service Denver CO
923 PM MDT Tue Aug 26 2025
COC005-039-270333-
/O.EXP.KBOU.FF.W.0021.000000T0000Z-250827T0330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Arapahoe CO-Elbert CO-
923 PM MDT Tue Aug 26 2025
...FLASH FLOOD WARNING WILL EXPIRE AT 930 PM MDT THIS EVENING FOR
NORTHWESTERN ELBERT AND CENTRAL ARAPAHOE COUNTIES...
The heavy rain has ended. Flooding is no longer expected to pose a
threat. Please continue to heed any remaining closures.
&&
LAT...LON 3957 10472 3970 10469 3971 10434 3954 10437
3954 10466 3957 10466
$$
RJKThe office that day
Everything else NWS Denver/Boulder, CO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 27, 1:40 PM MDT | Flash Flood Warning | BOU | Larimer | 3 hr |
| Aug 27, 2:23 PM MDT | Areal Flood Advisory | BOU | Weld | 3 hr |
| Aug 27, 2:57 PM MDT | Areal Flood Advisory | BOU | Weld | 3 hr |
| Aug 27, 3:01 PM MDT | Special Weather Statement | BOU | Broomfield | 44 min |
| Aug 27, 3:07 PM MDT | Severe Thunderstorm Warning | BOU | Adams, Weld | 38 min |
| Aug 27, 3:31 PM MDT | Areal Flood Advisory | BOU | Weld | 3 hr |
| Aug 27, 3:38 PM MDT | Special Weather Statement | BOU | Adams, Morgan | 52 min |
Nearby
Flash Flood Warnings in Colorado, 2025Every flash flood warning in 2025
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.