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Area forecast discussion 
National Weather Service Denver/Boulder Colorado
247 PM MDT Thursday Sep 3 2015

Short term...(this evening through friday)
issued at 152 PM MDT Thursday Sep 3 2015

Satellite showing increasing coverage of showers and
thunderstorms over the region with the incoming disturbance and
associated energy from the SW. Increased moisture into the region
helped to bring precipitable water values back up close to 1 inch with enough
upper level energy to sustain storms through the afternoon. Behind
the disturbance there is clearing that will help to bring partly
cloudy skies overnight and temperatures back into the 50s.

For tomorrow the upper level jet will move over the state along
with another disturbance that will bring another round of
afternoon storms. Increased moisture from the south combined with
upper level forcing from the preferable jet streak region
thunderstorms will be possible in the mountains and higher
foothills with a slight chance over the plains. Temperatures will
be slightly warmer then today with highs in the upper 80s.

Long term...(friday night through thursday)
issued at 152 PM MDT Thursday Sep 3 2015

Southwest flow aloft will remain over Colorado Friday and Saturday.
Another wave embedded in the flow will move across the state Friday.
Timing looks to be a little later in the it appears the
best chance for showers and storms will be during the early evening
hours. After drying early Friday...airmass will moisten up again
with precipitable water values climbing to around an inch over the
Front Range and eastern plains. The wave will be quick to move the threat for heavy rain will be low. Increased probability of precipitation
for this system Friday evening. On Saturday...models vary on the
amount of moist over the area...but enough should be around for more
afternoon and evening showers and thunderstorms. Best chance looks
to be over the higher terrain.

An upper level low will move across the northern rockies on Sunday.
This will cause flow aloft to turn westerly and push a weak cold
front through northeast Colorado. Temperatures will only be few
degrees cooler behind it. Airmass will be dry and will keep the
forecast dry. The GFS and European model (ecmwf) show a little quantitative precipitation forecast over far northeast
Colorado late Sunday night and early Monday due to the jet. Airmass
may be too dry for precipitation though. Will keep silent probability of precipitation in
during this time frame.

Westerly flow aloft will remain overhead Monday. This westerly flow
may bring breezy conditions at times over the higher terrain. This
combined with the dry airmass will elevated the fire danger.

Another trough will pass north of Colorado and push a cold front
through the area late Monday or early Tuesday. Some differences
among the models on how much moisture will be behind it. Will go
with low probability of precipitation for Tuesday afternoon and evening for this.

West to northwest flow will prevail behind the trough for Wednesday
and Thursday. Expect this to bring dry conditions with temperatures
near normal.


Aviation...(for the tafs through 00z Friday late afternoon)
issued at 152 PM MDT Thursday Sep 3 2015

Conditions will remain VFR for the next 24 hours. Scattered
showers and thunderstorms will continue to move through the area
bringing thunderstorms to the area with some heating before the
next surge. Main threats will be brief moderate to heavy rain with
the stronger storms along with gusty winds up to 30 miles per hour. Broken to
overcast deck will prevail into the evening but will only drop to 070
or 080. Overnight winds will return to drainage with a gradual
scattering out. For Friday look for another round of showers and
thunderstorms in the afternoon with an increasing cloud deck by


Bou watches/warnings/advisories...


Short term...Bowen
long term...meier

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