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Area forecast discussion 
National Weather Service Denver/Boulder Colorado
305 am MDT Monday Sep 1 2014

Short term...(today through tonight )
issued at 305 am MDT Monday Sep 1 2014

Suddenly it is September and we have classic September weather
right on schedule. Slightly drier and cooler air at low levels
today combined with subsidence aloft should significantly limit
the amount and strength of convection today. We should still
develop some shallow cumulus...but expect the threat of
precipitation to be limited to a slight chance near the eastern
border where there will be a bit more moisture and slightly cooler
air aloft. Even there showers are probably a stretch. 700 mb winds
from the west at 20-25 knots will mix into the mountains and
higher foothills this afternoon for the first dry and windy day in
a while...however fire danger is only rated moderate thanks to
regular precipitation through the Summer and humidities will not
be very low...just around 20 percent.

Only minor changes made to the forecast...trimming back plains
probability of precipitation a little more and putting in a bit larger diurnal range in
temperatures. Should be plenty of 30s and maybe a few 20s in the
mountains tonight.

Long term...(tuesday through sunday)
issued at 305 am MDT Monday Sep 1 2014

Models have fairly weak zonal flow aloft for the forecast area
Tuesday through Wednesday. For Wednesday night...the flow aloft
is west-southwesterly and a bit higher in speed with a weak trough
to move in...mainly to the north. The upper ridge is quite flat
and its center is well south of Colorado through middle week. The
synoptic scale energy is prognosticated to be downward in nature through
Wednesday...then weak upward Wednesday night. The boundary layer
winds look to be a mix between normal diurnal patterns and
downsloping Tuesday through Wednesday. Wednesday night...the
models bring down a cold front with upslope flow behind it.
Moisture is pretty sparse Tuesday through Wednesday night.
Precipitable water values range from 0.20 to 0.90 inch west to
east Tuesday and Tuesday night. On Wednesday and Wednesday night
values range from 0.30 to 0.60 inch form west to east. Dew points
range from the 20s f west to the 50s f east through the period.
Models still show decent cape over the plains late day Tuesday...
then very little for late day Wednesday. The quantitative precipitation forecast fields have no
measurable rainfall over the County Warning Area through the period. No probability of precipitation
Tuesday through Wednesday night. For temperatures...tuesday's
highs are 3-4 c warmer than today's. Wednesday's are up another
2-3 c. For the later days Thursday through Sunday...the upper
ridge is centered southeast to east of the forecast area with
west-southwesterly flow aloft for Colorado. Moisture begins to
increase Thursday and continue through Saturday. Sunday dries out
a bit.


Aviation...(for the tafs through 12z Tuesday morning)
issued at 305 am MDT Monday Sep 1 2014

VFR through tonight with light winds.


Bou watches/warnings/advisories...


Short term...gimmestad
long term...rjk

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