Area Forecast Discussion
Issued by NWS Denver/Boulder, CO

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FXUS65 KBOU 240241

Area Forecast Discussion
National Weather Service Denver/Boulder CO
841 PM MDT Fri Jun 23 2017

Issued at 840 PM MDT Fri Jun 23 2017

GOES-16 imagery before the sun set showed very nicely a breakup of
the stratus deck across a good portion of the Denver metro area.
Still scattered/broken decks along the Palmer and east of Denver
metro. Updated the grids to reflect the prevailing sky conditions
tonight. Otherwise the forecast looks on track.


.SHORT TERM...(This evening through Saturday)
Issued at 300 PM MDT Fri Jun 23 2017

Stratus stayed in over most of the plains today to produce a
cooler than the already cool forecast we had. Temperatures have
peaked only in the mid to upper 50s along the urban corridor.
An upper ridge from Arizona over the west coast will continue northwesterly
flow aloft across the area through Saturday. Upslope low level
flow will continue into tomorrow as well as high surface pressure
remains draped over the Great Plains. Some cloud cover will likely
remain over the plains tonight, more than originally forecast, so
have gone ahead and warmed the lows by a couple degrees. The
upper ridge will build in slightly to allow for warmer
temperatures tomorrow, readings in the low 70s are likely over the
plains, and 60s to 70s over the high terrain. Warming will allow
for weak destabilization, enough for a slight chance of showers
and weak storms mainly over elevated terrain.

.LONG TERM...(Saturday night through Friday)
Issued at 300 PM MDT Fri Jun 23 2017

Colorado will remain under a moderate northwest flow pattern
through the weekend. Airmass will remain mainly stable on the
plains while temperatures remaining cool with readings in the 70s
on Sunday. There will be a slight chance of late day showers and
thunderstorms in the mountains with slight instability in elevated

The ridge aloft over the Great Basin will move across Colorado
and into the central plains by Tuesday. This will allow
temperatures to warm back into the 90s. Expect there will be
isolated late day thunderstorms with some moisture streaming in
the westerly flow. Overall coverage of storms looks to be low. An
upper trof and cold front will move over Colorado Thursday and
Friday time frame with a cooling trend and a better chance for
storms. Only minor changes to current forecast needed.


.AVIATION...(For the 00Z TAFS through 00Z Saturday evening)
Issued at 840 PM MDT Fri Jun 23 2017

The stratus deck finally broke up just in the last hour at the TAF
sites though there are still SCT/BKN decks near DEN and APA.
Expect VFR conditions tonight through Saturday evening, though
there is a chance of BKN040 decks impacting APA and DEN tonight through
about 10Z. Winds will be light tonight and tomorrow morning,
generally expecting southerly flow 5-6 kts overnight, though
recent high res model runs have shown a very weak cyclone just
south of DEN, which would mean west at APA and E/ESE at DEN. Given
the weak pressure gradient the impacts of wind direction
uncertainty should be minimal. BJC should remain below 5 kts all
night. Saturday after 18Z winds should be NE at the TAF sites with
a strong surface high moving south across northwest Nebraska.




SHORT TERM...Kriederman
LONG TERM...Entrekin
AVIATION...Schlatter is the U.S. government's official web portal to all federal, state and local government web resources and services.