Special Weather Statement, NWS Denver/Boulder, CO

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1232 AM MDT Sat Jul 4 2026

.KEY MESSAGES...

- Last day of critical fire weather conditions as winds gradually
  relax. However, still plenty of hot, dry weather ahead.

- Another round of nocturnal (and potentially severe) convection
  possible tonight.

- Scattered strong to severe storms expected for the afternoon and
  early evening of the 4th.

- A few storms expected each day of the coming week, with the
  highest probabilities shaping up for Tuesday and Wednesday from
  the Front Range eastward.

&&

.DISCUSSION /Through Friday/...
Issued at 233 PM MDT Fri Jul 3 2026

Another day (and night) of uncertainty with regard to convective
development. CAMs have not been doing a great job of assessing
potential and duration of nocturnal convection, and amount of low
level moisture surging westward from MCSs in the Central/High
Plains the last couple of nights.

As of early this afternoon, weak convection has been developing
over the northern mountains and foothills. As that moves east onto
the plains, a couple storms are expected to tap into the higher
MLCAPE near 1500-2000 J/kg and become severe late this afternoon
into early evening. Where more uncertainty enters the forecast is
overnight, and that's when a couple pieces of the puzzle attempt
to come together and produce another round of strong to
potentially severe storms. That potential would extend farther
west toward the I-25 Corridor. That would be fueled by outflow
from the initial round of storms over the northern tier of
Colorado, and potentially another outflow from a more organized
storm complex (MCS) over Nebraska. That second surge would likely
arrive later in the evening, and that could spark storms that
linger well past midnight. At the same time, we'll also have some
upper level support from the left exit region of an upper level
speed max. While weakly capped, the lift from any upslope would
likely be enough to break through and initiate more storms. MLCAPE
by that time would be a little lower (800-1600 J/kg), but still
enough for a couple strong to severe storms that linger well past
midnight.

Saturday, the 4th of July, is still shaping up to serve up some
of nature's fireworks. It will likely be a more active
thunderstorm day with higher MLCAPE across the Front Range and
adjacent plains. Some patchy morning stratus is possible, but not
enough to significantly impact warming and cap erosion by early
to mid afternoon. MLCAPE is forecast to increase to 1500-2000 J/kg
along/east of the I-25 Corridor, but at the same time there is
plenty of uncertainty with exactly how far west the greatest
moisture and instability can hold (highly dependent on strength of
surges tonight). Most likely, deeper instability holds roughly
east of I-25, with lesser certainty west of I-25. We think storm
initiation will be in/very close to the Front Range Mountains and
Foothills by early afternoon, with eastward propagation across
the plains from mid afternoon through early evening. 0-6km bulk
shear is forecast to increase to 30-35 kts, enough for supercell
development. Initial isolated severe storms are expected to have a
large hail threat, and those storms may then attempt to organize
into a linear structure onto the plains with a greater high wind
threat (in addition to the hail). A failure mode would be if the
airmass remains too capped due to weak synoptic subsidence seen
arriving in the afternoon. Anyone planning outdoor celebrations or
activities tomorrow should remain weather aware and be prepared
to take shelter or move off open waters before storms arrive.
Finally, with the above mentioned arrival of subsidence, we do
think the vast majority of storms should clear the forecast area
before dark and any fireworks shows.

By Sunday and Monday, upper level ridging builds across Colorado.
While this will tend to stabilize things a bit, it will still be
hot and residual moisture means a continued chance of storms each
afternoon and evening. Typically this pattern has the most
convection occurring over Park County and the Front Range
Mountains into the Palmer Divide area, with lower probabilities to
the north and east. High temperatures will likely reach the 90-95
degree range over the plains, after just slight cooling (near
normal temps) for Saturday.

For Tuesday and Wednesday, the upper level ridge is forecast to
flatten with weak zonal flow developing across the forecast area.
As low level moisture remains locked in east of the Rockies,
instability builds slightly and shear improves so scattered
thunderstorms are expected both days with potential for a couple
severe storms. Temperatures will remain a few degrees above
normal.

Drying is expected for the latter portion of the weak as there is
growing confidence we remain under zonal flow aloft. Some lee
troughing is also forecast, which means the greatest chance of
storms will likely shift to the eastern plains while drier air and
a return of elevated fire weather conditions (with increasing
breezes) is expected over the high country.

&&

.AVIATION /06Z TAFS through 06Z Sunday/...
Issued at 1203 AM MDT Sat Jul 4 2026

Convection has moved eastward and away from the TAF sites at this
time. With the exiting convection, winds are expected to turn to
a more easterly component for the next hour or two before settling
into drainage for the overnight hours, though with storms expected
to persist over eastern Colorado and push into KS/NE through the
early morning, there is some uncertainty on whether winds maintain
an easterly component a tad longer than in the current TAF. There
is a chance we see some lower clouds move in with the easterly
flow as well. As such, have added a FEW005 to show this
potential, with the most likely time being between ~8Z-11Z this
morning.

With slightly higher confidence in drainage winds winning out,
expecting southerly winds to increase between 12Z-14Z before
turning to the southeast by early afternoon.

PROB30s remain in place for the potential for convection to begin
between 20Z-22Z across the TAF sites, with variable and gusty
winds between 30-40 kts possible with any passing storms. A few of
these storms may become severe (15% chance).

With wildfires still burning across the region, smoke will
continue to be a nuisance to slant range vis concerns, especially
near sunrise and sunset.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
None.

&&

DISCUSSION...20
AVIATION...9

Preliminary Local Storm Report
National Weather Service Denver CO
728 PM MDT Fri Jul 3 2026

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

0620 PM     Hail             3 NW Buckingham         40.64N 104.02W
07/03/2026  M1.25 Inch       Weld               CO   Public

&&

BR

Preliminary Local Storm Report
National Weather Service Denver CO
820 PM MDT Fri Jul 3 2026

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

0805 PM     Hail             7 SSW Reiradon Hill     40.48N 103.08W
07/03/2026  E1.25 Inch       Logan              CO   Trained Spotter

            Time estimated from radar.

&&

AA

Preliminary Local Storm Report
National Weather Service Denver CO
835 PM MDT Fri Jul 3 2026

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

0746 PM     Hail             2 WNW Union             40.36N 103.54W
07/03/2026  E1.00 Inch       Morgan             CO   Public

            Time estimated from radar.

&&

AA

Special Weather Statement
National Weather Service Denver CO
1042 PM MDT Fri Jul 3 2026

COZ041-045-046-040530-
North and Northeast Elbert County Below 6000 Feet/North Lincoln
County CO-Central and East Adams and Arapahoe Counties CO-
Elbert/Central and East Douglas Counties Above 6000 Feet CO-
1042 PM MDT Fri Jul 3 2026

...A LINE OF STRONG THUNDERSTORMS WILL IMPACT ARAPAHOE AND
NORTHWESTERN ELBERT COUNTIES UNTIL 1130 PM MDT...

At 1042 PM MDT, Doppler radar was tracking a line of strong
thunderstorms extending from 6 miles southeast of Byers to 5 miles
east of Elbert, or extending from 36 miles northwest of Limon to 41
miles west of Limon, moving east at 15 mph.

HAZARD...Wind gusts up to 50 mph and penny 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...
  Deer Trail and Fondis.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the weather situation closely and be alert for threatening
weather conditions.

Heavy rain is occurring with these storms and may lead to flooding.
Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3916 10451 3945 10440 3968 10417 3967 10393
      3939 10414 3914 10425
TIME...MOT...LOC 0441Z 277DEG 12KT 3965 10414 3943 10436 3920 10445

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...50 MPH

63

Preliminary Local Storm Report
National Weather Service Denver CO
1128 PM MDT Fri Jul 3 2026

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

1115 PM     Flash Flood      8 S Reiradon Hill       40.47N 103.01W
07/03/2026                   Logan              CO   Law Enforcement

            Flash flooding occurring along HWY 61
            between County Roads 4 and 8.

&&

Special Weather Statement
National Weather Service Denver CO
108 AM MDT Sat Jul 4 2026

COZ046-049-040800-
Washington County CO-North and Northeast Elbert County Below
6000 Feet/North Lincoln County CO-
108 AM MDT Sat Jul 4 2026

...A LINE OF STRONG THUNDERSTORMS WILL IMPACT SOUTHEASTERN WASHINGTON
AND NORTHEASTERN LINCOLN COUNTIES UNTIL 2 AM MDT...

At 108 AM MDT, Doppler radar was tracking a line of strong
thunderstorms extending from 6 miles northwest of Cope to over Genoa,
or extending from 29 miles south of Yuma to 10 miles east of Limon,
moving east at 5 mph.

HAZARD...Wind gusts of 50 to 55 mph and penny 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...
  Arriba, Genoa, Arickaree School and Cope.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the weather situation closely and be alert for threatening
weather conditions.

Torrential rainfall is also occurring with these storms and may lead
to flash flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 3931 10362 3959 10320 3982 10299 3982 10280
      3968 10280 3957 10287 3957 10315 3928 10316
      3916 10329
TIME...MOT...LOC 0708Z 290DEG 5KT 3974 10292 3951 10313 3926 10350

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...50 TO 55 MPH

63