Wednesday, March 6, 2013

Which Model Will Win?

Following up on the previous post, A Freaky Frontal Forecast, check out the contrast between the NAM and GFS forecasts for Alta through tomorrow at noon.  Due to differences in the intensity and position of the frontal band, the NAM calls for a total of only 0.10 inches of snow water equivalent and 1.1 inches of snow, whereas the GFS calls for 0.47 inches of snow water equivalent and 5.4 inches of snow.

Yup, there are a wide range of possibilities for tonight and tomorrow for any given location in northern Utah.


  1. Jim, I live in Virginia and all the talk around here is just how bad the American models are compared to the CMC, EURO and UKMET. This latest storm here kind of proved that true again. Perhaps you might see where those stand vs. these? The GFS and NAM totally missed the details of what was to happen on the Feb 14th storm (we were there then)...just a thought. Pem H

    1. "How Bad" is probably a bit of an overstatement, but the ECMWF has been ahead of the GFS for many years now. The gap between the GFS, CMC, and UKMET model is smaller and they are currently performing at fairly similar levels (although on any given day, one of those models might do better than the other).

      It is possible, if you so desire, to examine the performance of the various models at

      Some provocative discussion of this issue is available at

  2. NAM was's to hoping it is correct the rest of the storm/weekend (Wasatch back gets POUNDED!!!). These lows over reacting and heading to Mexico are problematic.