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Area forecast discussion 
National Weather Service Denver/Boulder Colorado
955 am MDT sun Apr 20 2014

issued at 927 am MDT sun Apr 20 2014

Middle level cloud deck has increased a bit as expected this morning.
This could limit daytime heating a bit especially in the lower
elevations so not entirely sure we will get showers to develop on
the plains as we may be just shy of convective temperatures. Will still
keep low probability of precipitation though as even if we dont reach convective temperatures we
could still see a few showers drift off the higher terrain from
our north and west. There may even be enough middle level moisture
combined with weak upslope to produce a bit of light rain.
Meanwhile...mountain areas are already seeing some cumulus
development so shower coverage will be higher there. Increased
probability of precipitation most mountain locales especially from the Front Range
mountains and foothills down into Summit/Park counties. Could even
see a couple more inches of snow above 10500 feet.


Short term...(today through tonight )
issued at 422 am MDT sun Apr 20 2014

Upper low continues to make slow northeastward progress across
northern New Mexico at this hour. Cyclone well evident on
satellite imagery. Also evident is the thick cloud shield
backwashing over south central and southeast Colorado. Skies have
cleared along the Front Range from Denver northward in the past
couple of hours as drier air filters down from Wyoming. However
should see a reversal in this trend over the next several hours
with moisture wrapping back into northestern Colorado as the upper low
tracks across southeastern Colorado. Partial sunshine this morning should
manage to destabilize the boundary layer sufficiently to spark a few
light rain showers over the Front Range and Palmer Divide by middle
to late morning. Rain chances look even better across the southeastern
corner of the County Warning Area where the airmass will be more moist and
unstable. Further heating and upslope flow this afternoon should
have little problem generating scattered showers and isolated
T-storms over the Front Range and Palmer Divide. Whereas the
plains airmass does not look as unstable for thunderstorms...
particularly north of Interstate 70...but enough to allow for
isolated rain showers by middle to late afternoon.

With the upper low moving away this evening...should see a quick
end to showers and clearing from northwest to southeast through
the evening. Later tonight...model 850-700 mb relative humidity and wind fields
show another surge of relatively cool and moist air backing into
northestern Colorado. Cross sections indicate a bank of low cloud across
the northestern corner of the state around 09z...and up against the Front
Range by 12z. Have added that to the forecast grids. Highs today
should be a few degrees above those observed yesterday with upper 60
to middle 70s on the plains...and upper 40s to around 60 in the high

Long term...(monday through saturday)
issued at 422 am MDT sun Apr 20 2014

For Monday...northeast Colorado will be in Post frontal regime as
winds shift east to southeast by afternoon. Could be some stratus
Monday am along with some moisture and a relatively stable
airmass. Some pooling of moisture over east slopes in the
afternoon with a slight chance for showers and thunderstorms.

For Tuesday...broad upper trough moves inland off West Coast with
increasing downstream southwest flow over Colorado. This will
result in warmer temperatures and gusty southwest winds. Closer to
the Colorado and Kansas border could be a marginal severe weather
potential as low level winds will be more south and southeast
with higher dewpoints streaming northward. Best chance for storms
will be over in Kansas but still bears watching for far eastern
Colorado. With the gusty winds and warmer temperatures may lead to
some fire weather issues for Tuesday afternoon and evening.
Highest impact would be over the Palmer Divide and possibly
further east depending on how much low level moisture can remain
or gets flushed out.

The broad upper trough sweeps across the region on Wednesday and
Wednesday night with an associated cold front moving over
northeast Colorado Wednesday afternoon. With some possible cooling
may lower any fire weather concerns. Moisture looks rather sparse
with this system over Colorado and keep most of the probability of precipitation over the
mountains and over far northeast Colorado.

Thursday looks to be cooler and breezy following the upper trough.
The ridging moves in for Friday with dry and warmer conditions.
Late Saturday may get interesting again as next strong upper trough
moves into the Great Basin with possible storms over the far east
plains with increasing moist...southeast flow.


Aviation...(for the tafs through 00z Monday afternoon)
issued at 927 am MDT sun Apr 20 2014

No significant changes planned. Still a low chance of showers
21z-02z but ceiling heights even with light showers should keep
visual Landing conditions in place. Winds transitioning to
north/northeast at 10-15 kts for the afternoon...then gradually
weakening and trending more westerly this evening before a weak
front pushes in 06z-09z. Could see cloud bases lowering to
4000-6000 feet above ground level with ils Landing conditions 12z-18z Monday. Then
any lower clouds would dissipate by 18z Monday.


Bou watches/warnings/advisories...


short term...Baker
long term...entrekin