Area Forecast Discussion
Issued by NWS Denver/Boulder, CO

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FXUS65 KBOU 251743

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1143 AM MDT Tue Oct 25 2016

Issued at 1132 AM MDT Tue Oct 25 2016

Trough axis is slower than expected and a bit weaker. There is an
area of scattered light showers. Mountain webcams showing some
light rain and snow over the ridges with the snow level around
10,500 feet. The shower band is just getting to I-70 in Summit
county now. Some better showers upstream of there but still not
expecting any roadway accumulations, perhaps a little on the
ground at the tunnel. On the plains it is looking like the showers
won`t be making it to the ground. Perhaps some sprinkles as the
band moves over. Rest of the forecast looks good, I delayed the
clearing a couple of hours tonight due to the slower trough


.SHORT TERM...(Today and tonight)
Issued at 426 AM MDT Tue Oct 25 2016

A very weak upper level disturbance is moving over the state this
morning with hardly any amplitude to it. Shower activity has been
spread over the western slope since last evening, but radar echoes
have been slow to move into the north central mountains. We should
see a mix of rain and snow move into the central mountains in the
next few hours as the weak trough axis continues in northeastward
trek through today. The airmass remains abnormally warm for late
October and snow levels should remain above 9000 or 10,000 feet. The
winds aloft are going to have a west to southwest component this
morning and then northwesterly this afternoon which will produce
drying downslope effects across the plains. For this reason, will
keep low pops across the plains, as only a few showers are
expected to move off the foothills through this morning and early
afternoon. Decreasing clouds and showers are expected overnight as
the weather disturbance moves out and upper level ridging moves
back over the state.

.LONG TERM...(Wednesday through Monday)
Issued at 426 AM MDT Tue Oct 25 2016

An upper level ridge will be over the area Wed and Thu with no
precip and abv normal temps.  Highs will be in the low to mid 70s on
Wed and then from 75 to 80 on Thu across nern CO.

On Fri there will be some increase in mid lvl moisture in the mtns
as a weak disturbance moves across nrn CO late Fri aftn into Fri
evening in sw flow aloft.  This feature may bring a slight chc of
showers to the mtns north of I-70 while the rest of the area will
remain dry. Highs on Fri will once again be well abv normal with
readings in the 75 to 80 degree range across the plains.

By the weekend an upper level ridge will be in place with swly flow
aloft. The ECMWF has a dry airmass over the area both days while the
GFS has increasing subtropical moisture mainly Sat night into Sun
affecting the mtns.  Previous fcst had a slight chc of showers in
the mtns Sat into Sat night so will not yo-yo the fcst at this point
and keep them in.  Over nern CO it will remain dry both days. Latest
data shows some minor cooling on Sat behind a wk back door fnt
across the plains which may drop highs back into the lower 70s
across nern CO.  On Sun a sfc lee trough dvlps over nern CO which
would lead to warmer temps with readings in the mid to upper 70s.

On Mon another weak upper level trough may affect nrn CO bringing a
slight chc of showers to the mtns.  Across nern CO it will remain
dry.  A pacific fnt may move across the plains in the aftn and
depending on timing temps could drop back into the upper 60s to
lower 70s.


.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
Issued at 1132 AM MDT Tue Oct 25 2016

VFR through tonight. WNW winds across KBJC may reach KDEN for a
little while through 20z, then northerly winds are expected the
rest of the afternoon into early evening.




SHORT TERM...Dankers
AVIATION...Gimmestad is the U.S. government's official web portal to all federal, state and local government web resources and services.