“MODEL GUIDANCE…HOW TO REALLY USE THEM

10-15 DAYS FROM A POTENTIAL STORM

EURO at 10 days shows a pattern
GFS plays a pattern look 10-15 days out but not sure of tracks and storm formation
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6-10 DAYS FROM A POTENTIAL STORM

EURO gets much better in seeing the Bigger storms and how they will evolve.
GFS gets the idea but tends to overplay storms and placement. Pattern shows up nicely here
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3-6 DAYS FROM A POTENTIAL STORM

EURO gets at is best in depicting a storm, esp west coast due to superior modeling
GFS tends to show BIG but pulls the magic act and poof it’s gone or reduced greatly. (lack o data out west is the cause)
CMC gets into the game with higher than average accuracy. Lean on this and EURO at this point
NAM on the edges of getting in range and starts to show a track but not an exact point
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0-2 DAYS FROM A POTENTIAL STORM

NAM gets real good most of the time but can overplay moisture and make it too warm on some levels
GFS is very good and is the model this season to lean on until the NAM gets a better score.
CMC/EURO are good but I switch over to the USA models since we get into a data rich enivironment.”

-RG

Those are the reasons why I do not get hyped up for a big snowstorm too many days in advance. It is also why I normally do not forecast snow totals 3-5 days out. There are too many variables at that point for me to be confident in one forecast.