Hazardous Weather Outlook
Issued by NWS Denver/Boulder, CO

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
FLUS45 KBOU 181754

Hazardous Weather Outlook
National Weather Service Denver/Boulder CO
1154 AM MDT Thu May 18 2017

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
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
Southeast Elbert County Below 6000 Feet/South Lincoln County-
Logan County-Washington County-Sedgwick County-Phillips County-
1154 AM MDT Thu May 18 2017

...Powerful Spring Storm System will Continue to Impact the
Outlook Area Through Friday...

This hazardous weather outlook is for northeast and north central

.DAY ONE...Today and Tonight

Moderate to heavy snowfall will continue in the Front Range
mountains and foothills and portions of the Interstate 25 corridor
through most of Friday. Snowfall rates of 2 to 4 inches per hour
are likely on the east facing mountain slopes and foothills, and
1 to 2 inches per at times across western portions of the I-25
urban corridor and Palmer Divide. This will produce slushy and
snow covered roadways resulting in hazardous driving conditions,
especially at elevations above 5500 feet. The higher mountain
slopes in Boulder and Larimer counties could see 1 to 3 feet of
snow by Friday morning.

At lower elevations east of I-25, precipitation will mainly be
rain or a mix of rain and snow today with locally up to an inch
of rain possible with the heavier showers. Any snow accumulation
will be light. The heavier rainfall could cause minor flooding of
streets, underpasses, small streams, and low lying areas. River
levels are expected to rise as runoff reaches the larger streams.
The heavy wet snow will accumulate on leafed out trees causing
limbs to break, and possibly cause scattered power outages.

Freezing temperatures on the plains tonight could injure or kill
tender plants.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

Moderate to heavy snowfall is expected to continue over the
mountains and foothills Friday morning, especially near Rocky
Mountain National Park. Snowfall totals in the high country could
range anywhere from 1 to 4 feet by Friday afternoon. Roads will
continue to be snowpacked, and tree branches will still be
threatened by the heavy snow and power outages may continue.
Winter-like difficult travel will begin to ease by Friday
afternoon and evening as snowfall rates decrease. At lower
elevations, snow is expected to lower to near 5200 feet Friday
morning, with 2 to 5 inches possible, though 9 to 18 inches isn`t
out of the question over the Palmer Divide and closer to the
Foothills. Widespread rain across the rest of the plains will
continue through the afternoon before tapering off. Low lying
areas may be prone to localized flooding and rivers are expected
to swell, do not try to cross flooded roads. This system will
bring temperatures that are 20 to 30 degrees below normal for mid
to late May. Low temperatures Friday night will likely be at or
below freezing along the urban corridor.

The mountains can expected scattered late day showers and
thunderstorms on Saturday. An unsettle pattern returns Sunday
through Tuesday with a chance of precipitation over much of the
forecast area all three days. There could be a few late day
thunderstorms as well.  Wednesday dries out.


Spotter activation will not be needed today or tonight. However,
snow, heavy rainfall, and flooding reports will be appreciated.


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.