Tuesday PM Update

Tricky forecast means both boom and bust potential high for Front Range
Ah yes, welcome to March along Colorado's Front Range, where the storm track is active, the bust potential is high, available moisture is higher, and one storm can dump a month's worth of snow in a matter of hours.

As we discussed last night, the first of two weather makers this week will be upon us Tuesday evening. This system is tricky, for a number of reasons, especially because marginal temperatures for snow mean the difference of virtually no accumulation and moderate accumulation.

The GFS and Euro have been juicy with this system for several days now, and it appears as other models are coming around to this as well. With plentiful moisture, the key to this forecast will be how fast we change to snow, and whether or not snowfall rates are high enough to overcome warm ground temperatures.

As as a cold front moves through Tuesday evening, winds will quickly shift to the north, temperatures will drop, and showers may pop up as early as 7pm; as strong evaporative cooling kicks in, rain is is liable to transition, perhaps quickly, to wet snow by mid-to-late evening. The amount of snow on the ground by morning will depend upon how much rain you receive before the snow develops, and your elevation.

Subject to how quickly the snow melts upon falling, neighborhoods west and south of the Denver metro area may see 3-6"+, with a few inches possible in the Denver area, and less to the north; again this will likely start as rain and then become a mix through the evening with all snow through the early morning hours. The timing is going to put the heaviest activity from 6pm to midnight.

Similar to the system that hit the southern metro a couple weeks ago, this system may roll through with lightning and thunder; if you see or hear that, expect the intensity of the showers to be strong. In a similar fashion to that former system, we do expect the best snowfall to again be to the south of Denver, Douglas County, and in the valleys/canyons of Boulder and Jefferson County.

Also, snow will increase over the central and northern mountains this afternoon and evening. A winter weather advisory has been posted for the Elkhead and Park Mountains, the Flattops and the mountains of southern Wyoming. Five to ten inches of snow are expected in the advised areas.

We'll continue to update you through the evening, and for all the latest stay with us on Twitter and Facebook, and subscribe to Weather5280 via email.