Alert archive / Colorado / Flash Flood Warnings in 2022

Flash Flood Warning 54, NWS Denver/Boulder, CO

August 15, 2022Arapahoe County, Douglas County, Colorado

NWS Denver/Boulder, CO issued this flash flood warning at Aug 15, 2022, 3:46 PM MDT for Arapahoe County, Douglas 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 counties it named.

The facts

Issued: Aug 15, 2022, 3:46 PM MDT (21:46 UTC)
Expired: Aug 15, 2022, 6:31 PM MDT
In force: 3 hr
Issued by: NWS Denver/Boulder, CO
Area: Storm-based polygon
Flood severity: None

Counties Arapahoe County, CO, Douglas County, CO

The radar

The Denver radar (KFTG), 34 km from the middle of the area, began a volume at 21:48 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, 9.8 hours before the alert went out and 335 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.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 17 J/kg
Mixed-layer CIN: -206 J/kg
Mixed-layer LCL: 1423 m above ground
0-6 km bulk shear: 5 kt
0-1 km storm-relative helicity: -44 m²/s²
0-3 km storm-relative helicity: -63 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Denver/Boulder, CO wrote its last area forecast discussion before this flash flood warning went out at Aug 15, 3:30 PM MDT, 16 minutes earlier.

Area forecast discussion, Aug 15, 3:30 PM MDT, 16 minutes before

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Hazardous weather outlook, Aug 15, 11:21 AM MDT, 4 hours 25 minutes before

Hazardous Weather Outlook
National Weather Service Denver/Boulder CO
1121 AM MDT Mon Aug 15 2022

COZ030>051-161730-
Jackson County Below 9000 Feet-
West Jackson and West Grand Counties Above 9000 Feet-
Grand and Summit Counties Below 9000 Feet-
South and East Jackson/Larimer/North and Northeast Grand/
Northwest Boulder Counties Above 9000 Feet-
South and Southeast Grand/West Central and Southwest Boulder/
Gilpin/Clear Creek/Summit/North and West Park Counties Above
9000 Feet-Larimer and Boulder Counties Between 6000 and 9000 Feet-
Jefferson and West Douglas Counties Above 6000 Feet/Gilpin/Clear
Creek/Northeast Park Counties Below 9000 Feet-
Central and Southeast Park County-
Larimer County Below 6000 Feet/Northwest Weld County-
Boulder And Jefferson Counties Below 6000 Feet/West Broomfield
County-
North Douglas County Below 6000 Feet/Denver/West Adams and
Arapahoe Counties/East Broomfield County-
Elbert/Central and East Douglas Counties Above 6000 Feet-
Northeast Weld County-Central and South Weld County-Morgan County-
Central and East Adams and Arapahoe Counties-
North and Northeast Elbert County Below 6000 Feet/North Lincoln
County-
Southeast Elbert County Below 6000 Feet/South Lincoln County-
Logan County-Washington County-Sedgwick County-Phillips County-
1121 AM MDT Mon Aug 15 2022

...FLASH FLOODING POSSIBLE THROUGH THIS EVENING IN THE FRONT
RANGE MOUNTAINS AND FOOTHILLS, SOUTH PARK, AND PALMER DIVIDE...

This hazardous weather outlook is for northeast and north central
Colorado.

.DAY ONE...This Afternoon and Tonight

Widespread showers and thunderstorms are expected over much of
the forecast area this afternoon and evening. Heavy rainfall
causing flash flooding will be the main threat with the storms.
While burn areas would be most at risk, the threat of flash
flooding also exists outside of the burn areas across the
foothills and Palmer Divide area. Heavier rain and urbanized
flooding will also be possible in portions of the Denver metro
area and adjacent plains. The stronger storms could produce 2
inches of rain in 45 minutes.

Be weather aware this afternoon and evening, and do not drive on
flooded roads.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday

A few showers and thunderstorms may linger mainly over the
mountains Tuesday, but the threat of burn area flooding will be
low. Drier weather is expected through the middle of the week,
though there will still be some afternoon storms over the mountains
with a low threat of burn area flooding. Some increase in
thunderstorm activity is expected for the weekend.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed today or tonight. However,
any reports of heavy rainfall or flooding would be appreciated.

RJK/Gimmestad

In the hours before

Local storm report, Aug 15, 2:49 PM MDT, 57 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DENVER CO
249 PM MDT MON AUG 15 2022

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0245 PM     HEAVY RAIN       1 SSE ST MARYS GLACIER  39.82N 105.64W
08/15/2022  M1.62 INCH       CLEAR CREEK        CO   TRAINED SPOTTER

&&

BR

Special weather statement, Aug 15, 3:08 PM MDT, 38 minutes before

Special Weather Statement
National Weather Service Denver CO
308 PM MDT Mon Aug 15 2022

COZ041-152145-
Elbert/Central and East Douglas Counties Above 6000 Feet CO-
308 PM MDT Mon Aug 15 2022

...A strong thunderstorm will impact portions of northwestern Elbert
County through 345 PM MDT...

At 308 PM MDT, Doppler radar was tracking a strong thunderstorm 4
miles north of Elbert, or 31 miles north of Colorado Springs, moving
east at 15 mph.

HAZARD...Winds in excess of 40 mph and nickel size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Elbert, Elizabeth, Kiowa and Ponderosa Park.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 3937 10466 3945 10434 3939 10434 3938 10433
      3933 10433 3932 10434 3931 10433 3920 10432
      3919 10463
TIME...MOT...LOC 2108Z 258DEG 11KT 3929 10454

MAX HAIL SIZE...0.88 IN
MAX WIND GUST...40 MPH

DANIELSON

Local storm report, Aug 15, 3:09 PM MDT, 37 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DENVER CO
309 PM MDT MON AUG 15 2022

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0300 PM     HEAVY RAIN       3 WSW SEDALIA           39.42N 105.02W
08/15/2022  M1.90 INCH       DOUGLAS            CO   TRAINED SPOTTER

            OBSERVED IN 30 MINUTES.

&&

BR

Local storm report, Aug 15, 3:42 PM MDT, 4 minutes before

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The office that day

Everything else NWS Denver/Boulder, CO issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 15, 1:10 PM MDT	Areal Flood Advisory	BOU	Gilpin	3 hr
Aug 15, 2:13 PM MDT	Flash Flood Warning	BOU	Larimer	3 hr
Aug 15, 2:17 PM MDT	Areal Flood Advisory	BOU	Larimer	3 hr
Aug 15, 2:20 PM MDT	Areal Flood Advisory	BOU	Jefferson	3 hr
Aug 15, 2:23 PM MDT	Flash Flood Warning	BOU	Larimer	3 hr
Aug 15, 3:02 PM MDT	Areal Flood Advisory	BOU	Douglas, Elbert	3 hr
Aug 15, 3:04 PM MDT	Areal Flood Advisory	BOU	Boulder	2 hr
Aug 15, 3:05 PM MDT	Areal Flood Advisory	BOU	Arapahoe, Douglas	115 min
Aug 15, 3:08 PM MDT	Special Weather Statement	BOU	Elbert	37 min
Aug 15, 3:15 PM MDT	Flash Flood Warning	BOU	Douglas	3 hr
Aug 15, 3:27 PM MDT	Severe Thunderstorm Warning	BOU	Arapahoe, Douglas, Elbert	48 min
Aug 15, 3:50 PM MDT	Severe Thunderstorm Warning Considerable damage threat	BOU	Adams, Arapahoe	40 min
Aug 15, 4:07 PM MDT	Areal Flood Advisory	BOU	Larimer	3 hr
Aug 15, 4:29 PM MDT	Severe Thunderstorm Warning	BOU	Elbert	18 min
Aug 15, 4:53 PM MDT	Areal Flood Advisory	BOU	Elbert	3 hr

Nearby

Flash Flood Warnings in Colorado, 2022 Every flash flood warning in 2022

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.