Hazardous Weather Outlook
Issued by NWS Denver/Boulder, CO

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FLUS45 KBOU 181042

Hazardous Weather Outlook
National Weather Service Denver/Boulder CO
442 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-
442 AM MDT Thu May 18 2017

...Strong spring storm with significant rain and snow...
...Scattered power outages and minor flooding possible...

This hazardous weather outlook is for northeast and north central

.DAY ONE...Today and Tonight

Heavy snow will continue across the Front Range Mountains and
Foothills, with snowfall rates of 1 to 2 inches per hour during
periods of heavier snow. Travel will become hazardous and
difficult due to snow and slush covered roads, and difficult if
not impossible in some areas north of I-70 due to the depth of

At lower elevations, heavy rain can be expected with minor
flooding of streets, underpasses, small streams, and low lying
areas possible through tonight. River levels are expected to begin
rising as runoff reaches the larger streams. Avoid any flooded
areas. If a road is closed due to high water, turn around and find
an alternate route. Along the I-25 Corridor including Denver,
Boulder, and Fort Collins, some snow will mix in with the rain
today. Then, as another shot of colder air moves in tonight,
rainfall is expected to turn over to mostly snow, with some
accumulation possible. Heavy wet snow may accumulate on fully
leafed out trees to cause limbs to break, resulting in scattered
power outages.

Temperatures on the plains will drop to or just above freezing
tonight. Protect newly planted or tender vegation by covering
with blankets or buckets.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

Moderate to heavy snowfall is expected to continue over the
mountains and high foothills Friday morning, especially near
Rocky Mountain National Park. Snowfall totals are expected to be 1
to 3 feet by Friday evening. 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 8 to
12 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.

Expect warmer and drier conditions Saturday through Monday, with
another system coming out of Canada for a wetter and cooler
Tuesday and Wednesday.


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


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