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FLUS45 KBOU 211519
HWOBOU

Hazardous Weather Outlook
National Weather Service Denver/Boulder CO
919 AM MDT Thu Aug 21 2025

COZ030>051-221530-
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-
919 AM MDT Thu Aug 21 2025

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

.DAY ONE...Today and Tonight

Record or near record heat will prevail today with highs pushing
into the mid and upper 90s across the I-25 Corridor and Plains.
Only isolated showers and thunderstorms will be possible in the
mountains and over the northern border area late this afternoon
and evening. They will produce just a brief period of light rain
and gusty winds to around 40 mph.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

A cooler and more active weather pattern can be expected for this
entire period. Scattered thunderstorms will develop Friday
afternoon and evening, and a couple storms may become severe with
large hail and locally heavy rainfall the primary threats. The
weather pattern will remain active this weekend with daily chances
of showers and thunderstorms, although Saturday should see less
activity. A few of these storms may be strong and also produce
locally heavy rain.

Monday will likely see more widespread showers and thunderstorms
and also a greater threat of heavy rainfall. There will be an
increasing potential for flooding as well, so stay tuned to the
latest forecasts. Rain chances will continue through the middle of
next week, with the highest chances in and near the mountains.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed today or tonight.

$$