Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

Area forecast discussion 
National Weather Service Denver/Boulder Colorado
411 am MDT Friday Oct 24 2014

..addition to 4th paragraph...

Short term...(today through tonight )
issued at 343 am MDT Friday Oct 24 2014

Quite a bit of wave clouds and gusty winds along the Front Range
and adjacent plains early this morning which has kept overnight
temperatures very mild with readings still in the 60s to around 70
at the base of the foothills. Given latest satellite and water
vapor imagery appears to be a back edge of the moisture over
central Utah and this should diminish the cloudiness later this
morning. This will lead to mostly sunny skies during the
afternoon. Simulated satellite imagery also showing wave cloud
dissipation by 18z.

High pressure ridge aloft will continue to build over Colorado
with continued warming temperatures. 700mb temperatures expected to rise
at least to +10 to +12c which will get temperatures into the
lower 80s over the plains. Record temperature for Denver today is
80 degrees...so looks like we might break a record. This is still
cooler than latest MOS guidance which has been running 2-5
degrees too warm.

Long term...(saturday through thursday)
issued at 323 am MDT Friday Oct 24 2014

In for another unseasonably warm day Saturday. 586 decameter
heights over northeast Colorado on Saturday. The resident airmass
also quite dry and stable with the passing upper ridge. By
afternoon 700 mb temperature up around 12c and with the deeply mixed
boundary layer should again see maximum temperatures in the 80-85 degree range
on the plains with the warmer readings up against the foothills
thanks to downsloping/southwesterly winds. May see more records broken.
Record high at Denver for the date is 80f.

Saturday night the 500mb ridge axis shifts east of the state
placing the region under strengthening southwesterly flow aloft. Models
show a weak middle-level pertabation being carried along by this
flow. Pressure falls on the plains leading to a tight Cross Mountain pressure
gradient will team up with this height fall anomaly and the formation
of a Lee Slope Mountain wave to produce gusty west-southwesterly winds on the mountain
ridges and east aspect of the Front Range late Sat night through
Sunday morning. Could see peak gusts in the 40-50 miles per hour range in
these areas. Temperatures expected to start quite mild on Sunday
esply along the Front Range due to these Chinook winds. However
through the day 700-500mb temperatures begin to creep downward in advance
of an upper trough swings across the Great Basin. 00z and 06z model
runs show the bulk of moisture and energy with this trough
tracking farther north across Montana and Wyoming. Still passage
of the trough Sunday night/Monday morning should end up producing
snowfall and gusty winds in the high country...and isolated to
scattered rain showers at lower elevations. Snow level expected to
start out around 10 thousand feet Sunday evening and then lower to
around 8 thousand feet by Monday afternoon. If showers still around
Monday evening...could see a dusting of snow on the Palmer Divide
and in the lower foothills. Snow totals in the high country during
the 36-hour period ending 00z/Tuesday generally in the 1-3 inch range
with upwards of 5 inches above timberline. While rain amounts at
lower elevations will be under a tenth of an inch. Skies are
expected to clear from north to south overnight. By Tuesday morning
temperatures just about everywhere will fall below the freezing
mark. Good bet this will end this year/S long growing season. Time
to think about blowing out outdoor sprinkler systems.

Tuesday through Thursday...flow aloft turns northwesterly with the
trough racing east and with an upper ridge rebuilding over the Great
Basin. Do not see any big warming rest of the week as weak weather
disturbances embedded in the flow keep middle-levels cool. One of these
ripples may bring a bit of snow to higher elevations in the northern mountains
on Wednesday. Lower elevations will remain dry for the remainder of
the week.

&&

Aviation...(for the tafs through 12z Saturday morning)
issued at 343 am MDT Friday Oct 24 2014

Wave cloud will dissipate between 16z-18z over local terminals.
Expect gusty west winds to continue at bjc until 16z before wave
breaks down. Weaker winds at apa/den with typical drainage from
the south. By afternoon...winds expected to shift more southeast
and east by late in the day.

&&

Bou watches/warnings/advisories...
none.
&&

$$

Short term...entrekin
long term...Baker
aviation...entrekin

National Weather Service Glossary of Abbreviations