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Area forecast discussion 
National Weather Service Denver/Boulder Colorado
925 am MDT sun Oct 4 2015

issued at 905 am MDT sun Oct 4 2015

Northeast Colorado remains shrouded in low clouds again this
morning while airmass even slightly cooler than yesterday.
Temperatures will only be in the 50s and 60s across the plains.
Airmass is slightly more subsident today with lack of any upper
support for showers this afternoon/evening. Expect only isolated
coverage in the mountains/nearby plains in areas on edge of
moisture/heating. Only minor changes to current forecast.


Short term...(today through tonight )
issued at 301 am MDT sun Oct 4 2015

A weak south-southwesterly flow aloft will continue over Colorado with weak middle
level subsidence today associated with a short wave ridge.
Persistent Ely flow will keep the threat of patchy fog going
through 15-16z over much of the northeast plains. Still some
lingering showers along the northern border this morning. In terms
of coverage should be a little less with a weak ridge
overhead. Will keep the mention of showers/thunderstorms in the grids. Low
clouds will keep mostly cloudy skies today with temperatures still
cool...middle 50s to middle 60s. Tonight...the weak south-southwesterly flow aloft
will continue...ahead of the next trough digging southward through
California. Persistence would suggest more fog developing overnight so
will keep this in the grids.

Long term...(monday through saturday)
issued at 301 am MDT sun Oct 4 2015

Monday will likely start off with some low clouds and patchy fog
on the plains with moist southeast flow and a weak Denver
cyclone. By afternoon...we should see better mixing and warming
on the plains as moisture depth decreases...allowing stratus to
effectively burn off. In the upper levels...ridging and warming
will tend to suppress convection. A weak shortwave may still ride
up the western sections of the forecast area late Monday afternoon
or Monday evening...but for the most part lift ahead of the deep
low over the southwest United States will hold off until Tuesday.
Still kept some low probability of precipitation near the foothills but confidence of
these has decreased for the Monday/Monday night time period.

Even on Tuesday...the best synoptic scale lift will stay well to
our south. However...there will be better jet dynamics to help
spread convection from the mountains onto the plains. Daytime
heating will also allow instability to increase ahead of short
wave especially along the Front Range/Palmer Divide. This would
support a few stronger storms but any severe threat is still
limited by marginal cape values of 500-1000 j/kg. Shower and storm
coverage is expected to increase into the evening hours and may
continue overnight with persistent but weak lift.

By Wednesday...the majority of the lift associated with the
southwestern U.S. Low will be displaced to our showers
chances will be lowering. Temperatures for Monday through
Wednesday should be near normal levels.

For Thursday through Saturday...a larger and more persistent
upper level ridge is expected to begin building from the
northern/central rockies into the southwest U.S. There may be a
weak embedded wave in northwest flow aloft Thursday or
Friday...otherwise mostly dry conditions should prevail during
this time frame with temperatures warming to above normal levels.


Aviation...(for the tafs through 18z Monday morning)
issued at 905 am MDT sun Oct 4 2015

IFR conditions remain at local terminals and expect a very slow
and gradual improvement to MVFR ceilings by early afternoon.
Expect another return of stratus/patchy fog again later tonight.


Bou watches/warnings/advisories...


short term...Cooper
long term...barjenbruch

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