Posted: Nov 27, 2012 10:48 AM by Meteorologist Matt Elwell
Updated: Nov 27, 2012 11:36 AM
It is hard to believe that we are past the Thanksgiving holiday and talking about temperatures in Southwest Montana near 50° later this week and into the weekend.
As a result, we are forecasting rain in the valleys rather than snow. Remember that at this point in the year, the average high temperature ranges between 34-38° for high temperatures and 10-15° on the low side.
These mild temperatures won't last long. The 6-10 day forecast points to slightly above average temperatures with slightly above average chances of precipitation. That means that we could see snow in mountain and high elevations from time to time during that stretch, but most areas will settle for rain rather than a meaning snowpack.
We do see a shift beginning to take effect in the 8-14 day range as the cooler air begins to settle across Eastern Montana and shift back toward the Southwest part of the state. Equal rain chances during that same time point to a drier set-up for the mid-range. This doesn't, however, mean that we won't pick up snow during this time frame. With colder air moving in, it actually could mean quite the opposite. We could see a series of systems trying to work into the area which could provide enough energy to bring snow back to the area.
The 30-day forecast does show the probability of colder air goes up significantly during the second half of December, especially in the Eastern part of Montana, though our precipitation probability does not go up during that same timeframe. That doesn't rule out the potential of significant snowfall in December by any means. Often, when you see a cooling trend like the one setting up for the second half of December, it indicates either a prolonged cold-snap or a series of arctic systems that will slice through the area. Unfortunately, these models are only guides, and if the initial data is off by a small amount, it can drastically change the long-term forecast.