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Area forecast discussion 
National Weather Service Denver/Boulder Colorado
908 PM MDT sun Apr 20 2014

issued at 902 PM MDT sun Apr 20 2014

Probably the last batch of showers moving southeast from Denver at
this time. There is still some weak convection upstream...but it
looks like little or no precipitation. Cold front is nearing
Cheyenne and should move into Denver around midnight. Little area
of moisture behind the front...still some potential for high
stratus in the late night and morning though not a sure thing and
maybe not everywhere. Forecast for Monday looks good with some low
level cooling and warming aloft. Any stratus will dissipate with
a very low level of convection over the mountains and maybe the
Palmer Divide. Even that may be too much.


Short term...(this evening through monday)
issued at 313 PM MDT sun Apr 20 2014

Isolated to scattered shower coverage continues this afternoon.
There have also been a few lightning strikes noted with a couple
of the cells. They will gradually decrease in coverage through the
course of the evening as airmass stabilizes...although there is a
weak short wave noted on satellite over northwest
Colorado/southwest Wyoming which could keep a few showers going a
little later. There is also a weak cold front pushing south across
east central Wyoming already and this should drop across northeast
Colorado later this evening. This too could keep isolated light
showers going until around midnight. The low level moisture behind
the front is rather limited but could still see a high stratus
deck develop behind front...enough for partly cloudy skies

On Monday...any high stratus deck would dissipate by middle to late
morning. There will be more sunshine and airmass is still
unstable enough over the higher terrain to warrant a low chance of
afternoon/evening showers and storms. On the plains...airmass
looks mainly capped with a slightly cooler boundary layer behind
tonights will maintain a dry forecast in the lower
elevations for now.

Long term...(monday night through sunday)
issued at 313 PM MDT sun Apr 20 2014

A progressive upper level flow pattern will prevail across the
state through the week with two periods of troughiness. An upper
ridge will bring warm temperatures to the region on Tuesday. At
lower levels...strong southerly flow should be establishing itself
across Texas and the Central Plains...some of which may come into
far eastern Colorado. A Lee trough will also develop over
northeast Colorado...setting up a bit of a dryline to the east of
Fort Morgan and Limon. Each afternoon will feature shower and
thunderstorm activity over the mountain areas due to the moisture
lingering over the higher terrain. Tuesday will be the warmest day
of the week as a cold front moves in Tuesday night along with
upper level troughing moving in from the west. Each of the models
show a progression of troughs and ridges through the week...with
weak ridging on Thursday and Friday giving way to a
strong...digging trough next weekend. Thursday and Friday have a
chance to be dry across the forecast area while the temperatures
remain around seasonal normals. The past several runs of the GFS
have been indicating a fairly strong system next weekend...but
the European model (ecmwf) had been showing more zonal flow through that period.
However...the latest run of the European model (ecmwf) seems to be coming around
to the GFS solution. For now will stick with temperatures around
normal over the weekend and a chance of showers across the
forecast area.


Aviation...(for the tafs through 12z Monday morning)
issued at 902 PM MDT sun Apr 20 2014

VFR conditions through Monday. Isolated thunderstorm south of
Denver will move out of the area. Cold front will bring north
winds around 06z. Areas of stratus clouds are expected to develop
with cloud bases around 050-070 above ground instrument approaches to
kden may be needed in the 10z-16z time frame.


Bou watches/warnings/advisories...


short term...barjenbruch
long term...dankers