Flash Flood Warning 16, NWS Denver/Boulder, CO

Issued

Jul 1, 2021, 4:36 PM MDT (22:36 UTC)

Expired

Jul 1, 2021, 6:00 PM MDT

In force

84 min

Issued by

NWS Denver/Boulder, CO

Area

Storm-based polygon

Flood severity

None

County Jefferson County, CO

The Denver radar (KFTG), 53 km from the middle of the area, began a volume at 22:36 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.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

169 
WGUS55 KBOU 012236
FFWBOU
COC059-020000-
/O.NEW.KBOU.FF.W.0016.210701T2236Z-210702T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Denver CO
436 PM MDT Thu Jul 1 2021

The National Weather Service in Denver has issued a

* Flash Flood Warning for...
  Northeastern Jefferson County in central Colorado...

* Until 600 PM MDT.

* At 436 PM MDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1.5 and 2 inches of 
  rain have fallen. 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...
  Arvada, Westminster, southwestern Broomfield, northern Wheat 
  Ridge, Rocky Flats and White Ranch Open Space.

This includes the following streams and drainages...
  Clear Creek, Van Bibber Creek, South Boulder Creek, Ralston Creek, 
  Walnut Creek, Deer Creek, Little Dry Creek, Big Dry Creek, Coal 
  Creek, Rock Creek and Tucker Gulch.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Excessive runoff from this storm will cause flash flooding of small 
creeks and streams, highways, streets, underpasses, drainage areas 
and other low lying spots.

&&

LAT...LON 3991 10533 3991 10517 3989 10517 3989 10515
      3989 10514 3989 10513 3990 10513 3990 10515
      3991 10515 3991 10510 3990 10510 3990 10508
      3990 10507 3991 10507 3991 10506 3979 10507
      3979 10535

FLASH FLOOD...RADAR INDICATED

$$

RPK

907 
WGUS75 KBOU 012314
FFSBOU

Flash Flood Statement
National Weather Service Denver CO
514 PM MDT Thu Jul 1 2021

COC059-020000-
/O.CON.KBOU.FF.W.0016.000000T0000Z-210702T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Jefferson CO-
514 PM MDT Thu Jul 1 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 6 PM MDT THIS EVENING 
FOR NORTHEASTERN JEFFERSON COUNTY...

At 514 PM MDT, Doppler radar indicated between 1.5 and 2 inches of 
rain have fallen. 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...
  Arvada, Westminster, southwestern Broomfield, northern Wheat 
  Ridge, Rocky Flats and White Ranch Open Space.

This includes the following streams and drainages...
  Clear Creek, Van Bibber Creek, South Boulder Creek, Ralston Creek, 
  Walnut Creek, Deer Creek, Little Dry Creek, Big Dry Creek, Coal 
  Creek, Rock Creek and Tucker Gulch.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Excessive runoff from this storm will cause flash flooding of small 
creeks and streams, highways, streets, underpasses, drainage areas 
and other low lying spots.

&&

LAT...LON 3991 10533 3991 10517 3989 10517 3989 10515
      3989 10514 3989 10513 3990 10513 3990 10515
      3991 10515 3991 10510 3990 10510 3990 10508
      3990 10507 3991 10507 3991 10506 3979 10507
      3979 10535

FLASH FLOOD...RADAR INDICATED

$$

RPK

103 
WGUS75 KBOU 012355
FFSBOU

Flash Flood Statement
National Weather Service Denver CO
555 PM MDT Thu Jul 1 2021

COC059-020005-
/O.EXP.KBOU.FF.W.0016.000000T0000Z-210702T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Jefferson CO-
555 PM MDT Thu Jul 1 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 6 PM MDT THIS EVENING FOR 
NORTHEASTERN JEFFERSON 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 1200 AM MDT Friday for 
Portions of central, north central, and northeast Colorado.

LAT...LON 3991 10533 3991 10517 3989 10517 3989 10515
      3989 10514 3989 10513 3990 10513 3990 10515
      3991 10515 3991 10510 3990 10510 3990 10508
      3990 10507 3991 10507 3991 10506 3979 10507
      3979 10535

$$

RPK

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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.