Brian Bledsoe

Model images below are from the EURO Model

Upslope Potential
The storm that is set to move through the area looks to produce some good rain
and snow for some of us. While amounts are both in question, one of the main
ingredients that models are focusing on is some pretty solid upslope. The
animation below shows wind speed and direction at roughly 5000 to 7000 feet
above the ground, from this morning through early Wednesday evening:

As low pressure moves through E/NE Colorado, the wind turns from the
east-southeast to northeast, and then finally to the north. That sustained fetch
from the northeast later tonight and early Wednesday will supply enough lift to
the atmosphere for some pretty healthy rain and snow amounts. While the heaviest
snow will likely fall in the mountains to the west and southwest of Denver, some
of that snow could make it to some lower elevations...specificially, the Palmer
Divide. 

Temperatures 
Obviously, temperatures are critical in determining who may see snow and who
will see all rain. Right now, the temperature trend hints at areas from the far
SE side of Denver southward to Monument getting cold enough for wet snow
tonight. The animation below runs from midday today through midday Wednesday,
and shows this trend:

Total Precipitation Potential

The map above clearly shows who is favored with the above setup. Areas along the
Palmer Divide and I-70 Corridor and northward will do the best with this storm,
with a pretty sharp cutoff to the south of that line. While the pictured amounts
may be a bit overdone in spots, it has the right idea with the potential...due
to the upslope that I mentioned earlier. How much of that is snow?

Again, while the model snow map above may be a bit overdone, it still has the
right idea. Given the warmer ground temperatures, and the actual temperatures
not being terribly cold, what falls versus what sticks will likely be two
different things...except in the mountains. Taking this map at face value, 2 to
7 inches of heavy wet snow would be possible from Monument to the southeast side
of Denver. Accumulation on the grass and anything elevated off the ground seems
to be the most likely scenario. Trees have been slow to "bud out", but any trees
that are would take a beating from that much snow.

In short...
Good rain and snow potential exists due to the upslope component of this storm.

Heaviest rain/snow will fall along the Palmer Divide / I-70 Corridor and
northward.

Temperatures late tonight and early Wednesday likely allow for some heavy wet
snow between SE Aurora and Monument...Douglas, Elbert, and far northern El Paso
County.

Actual pavement accumulation likely won't be that much, but the wet/heavy/gloppy
snow will stick easily to the grass and anything elevated off the ground.

Snow amounts outside of the mountains are uncertain, but a few inches seems
possible for the mentioned areas.

Upslope trouble tonight and early Wednesday?