Weather Story |
NWS Denver/Boulder, CO
For today and tonight:
Thunderstorms will develop in the mountains and foothills during
the early afternoon and across the adjacent plains by mid to late
afternoon. A large area of rain will develop with embedded slow
moving thunderstorms producing heavy rain. Some of the storms will
produce rainfall rates of one to two inches per hour that may stay
over an area for several hours. The main area of rain is expected
to move from the mountains onto the plains by late tonight, but
additional thunderstorm development is expected over the mountains
during the night so the heavy rain threat will continue at least
through this evening.
Widespread rain amounts of one to two inches are expected, with a
bit less in areas east of Sterling and Akron. There will likely be
areas where heavy thunderstorms develop that get 3 to 6 inches of
rain over a several hour period, which will be enough to cause
flooding. It is too early to tell exactly where and when this will
occur, but the main threat will be this afternoon over the
mountains, from mid afternoon into the evening over the foothills
and Front Range cities, and overnight on the plains.
For Wednesday through Monday:
A cool and moist airmass will be over the region Wednesday with
weak winds aloft. In addition, low level upslope flow will keep
easterly winds into the foothills. Showers and thunderstorms will
be possible for much of the day, with heavy rain possible. Slow
moving thunderstorms will be capable of producing one to two
inches of rain in less than an hour. In addition, the easterly
low level winds will help hold showers against the foothills. A
flash flood watch will remain in place for much of north central
and northeast Colorado through 6 PM Wednesday.
From Thursday through Monday, an upper level ridge will remain
over Colorado with slightly warmer temperatures. There will be
enough monsoonal moisture for a chance of afternoon and evening
thunderstorms each day, mainly across the mountains. Heavy rain
will be possible with the storms.
Formal spotter activation is not anticipated today but reports of
heavy rainfall or flooding will be appreciated.