OK, let's start with the basics:
Use NOAA's site. They are the best. NEVER trust the comercial sites. They get their info from NOAA anyway, so why go with filtered/manipulated info? NOAA has an automatically generated forecast system that goes out 7 days. Use this to get a general idea of what's ahead in the following week:http://ifps.wrh.noaa.gov/cgi-bin/dwf...&Y=&siteID=SLC
Now, let's get more detailed. There are several good forecast models used by the NOAA folks: GFS, NAM, MRF, EC & RUC. Go to the discussion part of NOAA's site to find out which of these models they currently trust the most:http://www.wrh.noaa.gov/slc/forecast...ct.php?pil=afd
Then, go to the model of choice and learn how to read the maps:http://www.wrh.noaa.gov/slc/forecast/models.php
Here's how to read the models:
- Start with the SL Pres/Prec Surface Level/Precipitation sequence. Use the loop feature to see the forecast in motion. All the models use Zulu (Grenwhich) time, which is, for Utah +8 hours difference. Some models go out furhter than others. GFS goes out the furthest, and ANY (commercial or otherwise) 10 -14 day forecast is based on this model.
- Once you get an idea of the weather systems coming to the place of interest, switch over the the 700mb or 850mb (atmospheric) temperature charts. In the Rockies, the 850mb temps need to be below -2C to support snow down below about 7,000'. Anything warmer DURING a storm will be trouble. Note: it is quite common for the temps to be above this during the day time BETWEEN storms and that is not detrimental to the skiing conditions.
- Look at a few of the models. The more agreement there is between them, the more likely that the forecast is accurate.
Right now, the models are dancing all over the place and I'd say none of them are much good beyond the next week or so.
That's pretty much it.