Flash Flood Warning 40, NWS Denver/Boulder, CO

Issued

Jul 29, 2021, 7:50 PM MDT (01:50 UTC)

Expired

Jul 29, 2021, 11:00 PM MDT

In force

3 hr

Issued by

NWS Denver/Boulder, CO

Area

Storm-based polygon

Flood severity

None

Counties Jackson County, CO, Larimer County, CO

The Cheyenne radar (KCYS), 123 km from the middle of the area, began a volume at 01:54 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.

708 
WGUS55 KBOU 300150
FFWBOU
COC057-069-300500-
/O.NEW.KBOU.FF.W.0040.210730T0150Z-210730T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Denver CO
750 PM MDT Thu Jul 29 2021

The National Weather Service in Denver has issued a

* Flash Flood Warning for...
  Central Jackson County in north central Colorado...
  Northwestern Larimer County in north central Colorado...

* Until 1100 PM MDT.

* At 750 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 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...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...
  Walden, Brownlee and Coalmont.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

&&

LAT...LON 4091 10615 4095 10608 4090 10598 4077 10595
      4069 10593 4064 10603 4062 10615 4059 10622
      4052 10636 4057 10646 4073 10647

FLASH FLOOD...RADAR INDICATED

$$

Danielson

692 
WGUS75 KBOU 300244
FFSBOU

Flash Flood Statement
National Weather Service Denver CO
844 PM MDT Thu Jul 29 2021

COC057-069-300500-
/O.CON.KBOU.FF.W.0040.000000T0000Z-210730T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Jackson CO-Larimer CO-
844 PM MDT Thu Jul 29 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 11 PM MDT THIS 
EVENING FOR CENTRAL JACKSON AND NORTHWESTERN LARIMER COUNTIES...

At 844 PM MDT, Doppler radar indicates that thunderstorms have 
weakened over Jackson and northwest Larimer Counties. However, there 
are stronger storms that could move into the area in the next hour. 
Between 2 and 3 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...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...
  Walden, Brownlee and Coalmont.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

&&

LAT...LON 4091 10615 4095 10608 4090 10598 4077 10595
      4069 10593 4064 10603 4062 10615 4059 10622
      4052 10636 4057 10646 4073 10647

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...0.5-1 INCH IN 2 HOURS

$$

TH

Flash Flood Warnings in Colorado, 2021Every flash flood warning in 2021

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.