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Area forecast discussion 
National Weather Service Denver/Boulder Colorado
905 PM MST Wednesday Mar 4 2015

issued at 905 PM MST Wednesday Mar 4 2015

All snow shower activity has dissipated and skies across the
forecast area are mostly clear. Temperatures have already
plummeted at some of the favored cold Limon and
Walden...which are below zero. Snow cover will allow more
locations to drop to the zero degree mark. Drainage winds will
then kick induring the early morning hours...causing temperatures
to rise a little. Mostly clear skies should prevail...unless
patchy fog develops in the Platte River basin between Denver and
Greeley. Other than removing the mention of evening snow changes to the forecast are needed.

Update issued at 557 PM MST Wednesday Mar 4 2015

Just a couple lingering flurries and a few clouds over the
mountains and Denver metropolitan area. These will be dissipating very
soon with a mostly clear and very cold night across the forecast
area. Adjusted temperatures downward a few degrees in snow covered low
lying areas where winds will be nearly calm overnight...allowing
strong radiational cooling. Should see a few below zero readings
on the plains and even dia could quickly drop to around zero this
evening before drainage winds kick in overnight.


Short term...(this evening through thursday)
issued at 109 PM MST Wednesday Mar 4 2015

With lingering moisture and low level instability in the boundary
layer combined with upslope near the foothills some convective
snow has formed over eastern Boulder County. These
snow showers will continue through the afternoon before winds
switch over to a more southwesterly direction this evening. In
addition isolated snow showers continue in the mountains until
later this evening. Ceilings will clear overnight on the plains
bringing temperatures down to single digits. With downsloping off
the Palmer Divide along with westerly downslope winds off the
foothills this will allow for most regions on the plains to stay
fog free. However...southern Weld will have light winds and
combined with local topography cooler air will be able to pool in
low lying areas bringing a small chance for some patchy fog
formation early tomorrow morning.

For Thursday upper level flow will turn more northwesterly
bringing a drier and warmer flow to the region. Temperatures will
rebound to just below seasonal normals.

Long term...(thursday night through wednesday)
issued at 109 PM MST Wednesday Mar 4 2015

On Thursday upper level trough continues to dominate
the central and eastern United States...with a large upper level
ridge of high pressure along the West Coast. Colorado lies between
these two systems under the influence of a dry northwest flow
aloft. This pattern will bring dry conditions to north central and
northeastern Colorado through the weekend...with the exception of
a few High Mountain snow showers on Sunday. Temperatures over
eastern Colorado will warm to above normal values on Friday as
warm air advection combines with weak downslope flow. Cooler
temperatures are expected east of the mountains over the response to a couple of weak cool front moving across
northeastern Colorado.

Models begin to diverge by early next week. The European model (ecmwf) has a large
upper level ridge building into the Rocky Mountain region...while
the GFS has a more zonal flow. Either way it looks to be warm and
dry....with high temperatures near 70 in Denver by Wednesday.


Aviation...(for the tafs through 06z Thursday evening)
issued at 905 PM MST Wednesday Mar 4 2015

VFR conditions should prevail across Denver area airports tonight
and Thursday. Kden and kapa should see drainage winds develop
around 10-14 knots. The drainage winds should keep the threat of
fog to the north and east of the Denver metropolitan area airports.


Bou watches/warnings/advisories...


short term...Bowen
long term...Kalina

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