Flash Flood Warning 4, NWS Denver/Boulder, CO

249 
WGUS75 KBOU 240851
FFSBOU

Flash Flood Statement
National Weather Service Denver CO
251 AM MDT Wed Jun 24 2026

COC005-039-073-241015-
/O.CON.KBOU.FF.W.0004.000000T0000Z-260624T1015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Arapahoe CO-Elbert CO-Lincoln CO-
251 AM MDT Wed Jun 24 2026

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 415 AM MDT EARLY THIS
MORNING FOR ELBERT, LINCOLN AND EASTERN ARAPAHOE COUNTIES...

At 251 AM MDT, Doppler radar indicated thunderstorms producing heavy
rain approaching the warned area. Approximately 2 inches of rain have
fallen from earlier thunderstorms. Additional rainfall amounts up to
0.5 inches are possible in the warned area. Flash flooding is ongoing
or expected to begin shortly.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Radar indicated.

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...
  Cottonwood Valley and Cedar Point.

This includes Interstate 70 between Agate and Limon.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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 10393 3966 10381 3958 10371 3957 10371
      3957 10369 3951 10361 3931 10372 3928 10386
      3953 10397
PARTITION...608005

FLASH FLOOD...RADAR INDICATED

$$

BRQ

383 
WGUS75 KBOU 241007
FFSBOU

Flash Flood Statement
National Weather Service Denver CO
407 AM MDT Wed Jun 24 2026

COC005-039-073-241017-
/O.EXP.KBOU.FF.W.0004.000000T0000Z-260624T1015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Arapahoe CO-Elbert CO-Lincoln CO-
407 AM MDT Wed Jun 24 2026

...FLASH FLOOD WARNING WILL EXPIRE AT 415 AM MDT EARLY THIS MORNING
FOR ELBERT, LINCOLN AND EASTERN 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 10393 3966 10381 3958 10371 3957 10371
      3957 10369 3951 10361 3931 10372 3928 10386
      3953 10397
PARTITION...608005

$$

BRQ

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1138 PM MDT Tue Jun 23 2026

.KEY MESSAGES...

- A few strong to severe thunderstorms lingering overnight.

- Additional rounds of severe storms expected Wed and Thu for the
  lower elevations, with increasing flash flooding risk.

- Locally critical fire weather conditions on Wednesday. Fire
  danger increases considerably this weekend, as much hotter,
  drier and winder weather arrives.

&&

.DISCUSSION /Through Tuesday/...
Issued at 1255 PM MDT Tue Jun 23 2026

The busy week of severe weather rolls on for our area with today
likely bringing the highest risk of the week for the urban corridor.
This is a complex forecast given the risk each day will depend on
earlier convection. Thus, the risk for this evening will depend on
how the afternoon evolves, but multiple rounds of strong to severe
thunderstorms are possible today. Following this morning's cold
front, winds are northeast and eventually are expected to turn to
the east behind an outflow boundary from storms in Kansas and
Nebraska by later this afternoon. This will further advect moisture
into our area. A subtle shortwave trough should move across northern
Colorado this evening providing better lift to the area.

The ingredients look to be in place for a potentially lengthy severe
weather threat today, but a strong cap is currently in place that
will need to be overcome this afternoon/evening. Unusually high
dewpoints for our area (> 55 degrees) are possible for much of the
day into the evening. MLCAPE values could exceed 1500-2000 J/kg for
much of the afternoon and evening across the entire plains. 0 to 6
km bulk shear will be around 50 to 70 kts, possibly even reaching 90
kts. 0 to 3 km storm relative helicity values could be around or
even slightly exceed 100 to 200 m2/s2. CAMs are showing a wide
variety of solutions, especially once we reach this evening, likely
due to the aforementioned potential for a cap to be in place as well
as the strength/timing of the shortwave. With the incoming
shortwave, we believe the cap should be able to be overcome, leading
to widespread showers and thunderstorms tonight and overnight.

The Storm Prediction Center has included nearly the entire I-25
corridor and plains in an enhanced (3/5) risk for today. The
greatest threats today will be large hail (2 inches or greater in
diameter followed by damaging wind gusts (> 70 mph). There is also
the threat for a tornado or two and/or landspouts.

Isolated to scattered storms are expected to initiate along the
Cheyenne Ridge and Palmer Divide around 1pm to 4pm this afternoon.
By this evening, as the better lift arrives, convection should
increase in coverage along the I-25 corridor and move through our
area from NW to SE. The highest threat window for the Denver metro
would be between about 9pm and 3am tonight with the threat
continuing possibly through as late as sunrise for our far
southeastern plains. We want to emphasize that this is a somewhat
unusual nocturnal threat for our area.  Large hail looks to be the
main impact from evening and overnight convection.

The flooding threat will increase as the week goes on given the
amount of rainfall that has fallen, especially on the eastern
plains, where 0.25-0.50" has already fallen in the last few days.
Even tonight, some areas on the eastern plains could see a quick
inch of rainfall. Between Wednesday and Thursday, some areas could
pick up an additional 1 to 1.5 inches of rainfall.

A Red Flag Warning remains in effect for today for the mountains due
to the threat of locally critical fire weather conditions. This
threat will continue tomorrow. See the Fire Weather Discussion for
more details. Wildfires in Utah will continue to produce smoke and
the flow aloft will carry it into Colorado for at least the next few
days. While the near surface smoke density looks quite minimal, the
smoke will be thicker at mid and high levels and will keep some hazy
conditions around the area particularly each night and early morning.

Wednesday and Thursday will continue to bring a risk for severe
weather as shortwaves continue to rotate around the high pressure
centered in Texas. Thus, much of the plains is already highlighted
in a slight (2/5) risk from the Storm Prediction Center for
Wednesday and Thursday. The threat each day will evolve based on how
previous convection plays out. We currently expect dewpoints in the
50s and low 60s to continue as well as MLCAPE values between 1000
and 2000 J/kg particularly on Wednesday with only slightly lower
dewpoints and MLCAPE on Thursday expected as of now.

Friday through the weekend should bring less showers and
thunderstorms, but there will still be a chance especially for the
eastern plains, given only zonal flow aloft. The heat will return
for the weekend into next week with temperatures well into the 90s
forecast as the ridge builds to our east. Fire weather concerns will
also increase for the mountains and mountain valleys on Saturday and
Sunday, looking increasingly concerning due to some stronger wind
gusts.

&&

.AVIATION /06Z TAFS through 06Z Thursday/...
Issued at 1122 PM MDT Tue Jun 23 2026

Still can't rule out a tstm (20 percent chance) moving across DIA
and possibly APA by 07z as there are a few storms to the north
moving southeast. Otherwise may see ceilings between 6000 and 7000
ft thru 08z. After 08z stratus down to 2500 ft may affect all
three airports thru 15z on Wed. Winds should be E or ENE overnight
and then may become light and variable by 12z.

On Wed, should see stratus burn off by 15z or 16z with widely sct
tstms developing by 20z or 21z. For now have left prob30 in the
tafs for tstms between 20z and 01z with brief gusts up to 35 kts.
Depending on how things setup there could be some threat for a
strong/severe storm as well. Winds will become ESE/SE by 17z and
continue thru the aftn.

After a lull in tstm activity by 00Z or 01z there is some threat
of additional activity by 04z so have included a prob30 for this
potential.

&&

.FIRE WEATHER...
Issued at 1255 PM MDT Tue Jun 23 2026

Widespread elevated to critical fire weather conditions are
possible each of the next two days in the mountains and mountain
valleys. Humidity will drop to around 10% in the valleys today,
with only a slight improvement Wednesday. Wind gusts up to 35 mph
are possible today with only slightly lower wind speeds on
Wednesday.

Fire weather concerns will be very low on Thursday and Friday as
moisture increases and thunderstorms return. These will be most
widespread Thursday with localized wetting rains.

Warmer, drier, and windier weather remain increasingly likely for
Saturday, Sunday, and early next week. Wind gusts in the
mountains, including both valleys and higher elevations, are
likely to exceed 40-50 mph (80% chance), sustaining highly
critical fire weather conditions both days.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Fire Weather Watch from 11 AM MDT Wednesday through Wednesday
afternoon for COZ212-213.

Red Flag Warning from 11 AM to 6 PM MDT Wednesday for COZ214.

&&

DISCUSSION...MV
AVIATION...RPK
FIRE WEATHER...MV

Preliminary Local Storm Report
National Weather Service Denver CO
941 PM MDT Tue Jun 23 2026

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

0925 PM     Hail             1 SSW Wiggins           40.21N 104.08W
06/23/2026  E1.75 Inch       Morgan             CO   Law Enforcement

            Vehicle and camper destroyed by large hail
            in the Kiowa Park Subdivision.

&&

Preliminary Local Storm Report
National Weather Service Denver CO
1025 PM MDT Tue Jun 23 2026

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

1025 PM     Tstm Wnd Gst     2 NNW Wiggins           40.25N 104.08W
06/23/2026  M58 MPH          Morgan             CO   Mesonet

&&

Preliminary Local Storm Report
National Weather Service Denver CO
1049 PM MDT Tue Jun 23 2026

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

0934 PM     Hail             2 E Wiggins             40.23N 104.04W
06/23/2026  M1.75 Inch       Morgan             CO   Trained Spotter

&&

Preliminary Local Storm Report
National Weather Service Denver CO
1053 PM MDT Tue Jun 23 2026

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

0957 PM     Hail             2 E Wiggins             40.23N 104.04W
06/23/2026  M2.00 Inch       Morgan             CO   Trained Spotter

&&

Preliminary Local Storm Report
National Weather Service Denver CO
1055 PM MDT Tue Jun 23 2026

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

0858 PM     Hail             3 SSE Kiowa             39.31N 104.44W
06/23/2026  E1.00 Inch       Elbert             CO   Public

&&

AA

Preliminary Local Storm Report...Summary
National Weather Service Denver CO
1122 PM MDT Tue Jun 23 2026

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

1025 PM     Tstm Wnd Gst     2 NNW Wiggins           40.25N 104.08W
06/23/2026  M58 MPH          Morgan             CO   Mesonet

0856 PM     Hail             Wiggins                 40.23N 104.07W
06/23/2026  E3.00 Inch       Morgan             CO   Public

0857 PM     Hail             Wiggins                 40.23N 104.07W
06/23/2026  E2.75 Inch       Morgan             CO   Public

            Location estimated from radar.

0957 PM     Hail             2 E Wiggins             40.23N 104.04W
06/23/2026  M2.00 Inch       Morgan             CO   Trained Spotter

0856 PM     Hail             1 SSW Wiggins           40.22N 104.08W
06/23/2026  E2.00 Inch       Morgan             CO   Public

0853 PM     Hail             Wiggins                 40.23N 104.07W
06/23/2026  E2.00 Inch       Morgan             CO   Public

            Time estimated from radar.

0934 PM     Hail             2 E Wiggins             40.23N 104.04W
06/23/2026  M1.75 Inch       Morgan             CO   Trained Spotter

0925 PM     Hail             1 SSW Wiggins           40.21N 104.08W
06/23/2026  E1.75 Inch       Morgan             CO   Law Enforcement

            Vehicle and camper destroyed by large hail
            in the Kiowa Park Subdivision.

0909 PM     Hail             3 SE Weldona            40.32N 103.92W
06/23/2026  E1.75 Inch       Morgan             CO   Trained Spotter

0855 PM     Hail             4 SE Orchard            40.29N 104.07W
06/23/2026  E1.75 Inch       Morgan             CO   Trained Spotter

0850 PM     Hail             Wiggins                 40.24N 104.08W
06/23/2026  E1.75 Inch       Morgan             CO   Public

0853 PM     Hail             1 SSW Wiggins           40.21N 104.08W
06/23/2026  E1.50 Inch       Morgan             CO   Public

            Time estimated from radar.

0836 PM     Hail             1 W Jackson Reservoir   40.38N 104.09W
06/23/2026  E1.50 Inch       Morgan             CO   Public

            Report from mPING: Ping Pong Ball (1.50
            in.).

0858 PM     Hail             3 SSE Kiowa             39.31N 104.44W
06/23/2026  E1.00 Inch       Elbert             CO   Public

0844 PM     Hail             1 W Jackson Reservoir   40.38N 104.09W
06/23/2026  E1.00 Inch       Morgan             CO   Public

            Report from mPING: Quarter (1.00 in.).

&&