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Johnstown, CO Severe Weather Alertstar_ratehome

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Personal Weather Station
Location: Johnstown, CO
Elevation: 4816ft
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Active Weather Alerts

Special Weather Statement
Issued: 11:18 PM Aug. 11, 2026 – National Weather Service
...A LINE OF STRONG THUNDERSTORMS WILL IMPACT EAST CENTRAL DENVER...
ARAPAHOE...SOUTHERN WELD AND CENTRAL ADAMS COUNTIES UNTIL 6 PM MDT...

At 518 PM MDT, Doppler radar was tracking a line of strong
thunderstorms extending from near Prospect Valley to near Watkins, or
extending from 29 miles southeast of Greeley to 17 miles east of
Denver, moving southeast at 20 mph.

HAZARD...Wind gusts up to 50 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects.

Locations impacted include...
Northeastern Aurora, eastern Denver International Airport, Manila
Village, Prospect Valley and Watkins.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

If on a lake, get out of the water and secure loose items. Boaters
can expect strong gusty winds and locally higher waves. Boaters
should seek safe harbor immediately.

&&


MAX HAIL SIZE...0.00 IN;
MAX WIND GUST...50 MPH

Air Quality Alert
Issued: 10:11 PM Aug. 11, 2026 – National Weather Service
...OZONE ACTION DAY ALERT FROM 400 PM TUESDAY UNTIL 1200 AM
WEDNESDAY...

The Colorado Department of Public Health and Environment has
issued the following...

WHAT...Ozone Action Day Alert.

WHERE...Douglas, Jefferson, Denver, western Arapahoe, western
Adams, Broomfield, Boulder, Larimer, and Weld Counties

WHEN...400 PM Tuesday August 11 to 1200 AM Wednesday August 12

IMPACTS...Ozone Action Day Alert is now in effect for the Front
Range Urban Corridor.  On Tuesday, hot and stagnant weather will
allow ozone to reach the Unhealthy for Sensitive Groups level. On
Wednesday, unsettled weather and scattered showers will limit
ozone development, and moderate concentrations are expected.  For
Colorado air quality conditions, forecasts, and advisories, visit:
https://www.colorado.gov/airquality/colorado_summary.aspx   If
possible, please help us reduce ozone pollution by limiting
driving gas and diesel-powered vehicles until midnight, Tuesday
night, August 11, 2026. Colorado is also addressing ozone
pollution through state policies. For more information about
health impacts and how ozone pollution forms in Colorado, visit:
https://cdphe.colorado.gov/ozone- pollution-and-your-health

HEALTH INFORMATION...Increasing likelihood of respiratory symptoms
and breathing discomfort in active children and adults and people
with lung disease, such as asthma. Active children and adults, and
people with lung disease, such as asthma, should reduce prolonged
or heavy outdoor exertion.

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