The most popular phrase used by meteorologists this season was “the weather pattern looks like it will change in the next week or two.” Yeah, right!
Unfortunately for most locations in the U.S., the weather pattern didn’t change much during the 2011-2012 season and predictions of a “pattern change in two weeks” failed to materialize on most occasions. For the last five to ten years that I’ve spent studying snow forecasting in the mountain west, I’ve noticed that the overall weather pattern does change every 3-6 weeks or so. During one month, the east might be cold and snowy while the west is warmer and drier, and then this will flip flop. Not so this year, though, as the weather pattern we started the season with never changed. Let’s put it all in perspective and wrap up the past six months.
In this graphic, developed by Dr. Andrew Slater from Boulder’s National Snow & Ice Data Center, the colored dots show the rank of this season compared to the last 30 years. If this was the best season (most snow) of the last three decades, the dots are colored purple. For the worst season of the last 30 years, the dots are colored black.
As of March 28th (a good time to rank the season with most skier traffic falling off after March), the dots show the Pacific Northwest and Northern Rockies leading the west with near record-breaking snow for some areas (purple dots). For example, Mt. Bachelor saw 473 inch, which was 135% of average. And Crystal Mountain in Washington recorded 546 inches, or 146% of their long-term average.
What this chart really illustrates is the influence of La Nina, which is the cooling of the central Pacific Ocean. Because this body of water is so big, small temperature changes here affect weather all over the world. In North America, La Nina consistently brings big snow totals to the northern third of the U.S. and the west coast of Canada. However, in the central part of the U.S. – from Tahoe to Utah to Colorado – La Nina’s affects are more hit and miss. Some years it brings lots of snow (like the 2010-2011 season) and some years it doesn’t (like this season). Squaw Valley, California and Park City in Utah finished at about 75% of average snow, and for the Tahoe region, most of this snow came in March after a very dry December and January.
Further south, areas like Taos, New Mexico saw some great early-season snow and a few late-season storms, but overall La Nina is not very kind to the southern states. Still, Southern California, Arizona, and New Mexico saw more snow than a typical La Nina winter, and we’ll take it! These regions always look for an El Nino to bring the bigger totals…
Finishing our wrap-up in the east, the main story was a lack of consistency. Every time a big storm would drop snow and put a chill in the air, the following storm a few days later would track further west allowing warm air and rain to stream up from the south and put a damper on conditions. Killington finished with 65% of average snow while up the road at Stowe, their seasonal snow totaled only 57% of average. As they say, better luck next season…or in late April? Yes, during the third week of April, after all the eastern resorts had closed, the atmosphere had a little fun and put down up to a foot of snow in some areas. In fact, Seven Springs, PA re-opened for a day for fans to enjoy the April freshies. And with pictures like this, why not? It looks like full-on winter! Just a few months too late, unfortunately…
As I end this article, I know what you’re thinking: “What’s going to happen next season? C’mon Joel, give us good news!” Well, I can’t give you any news because long range forecasting is just plain awful for the purposes of predicting snow. However, I can tell you that no two seasons are ever alike, so if you didn’t like what you saw this year, just wait another eight months and let’s try it again!
Meteorologist Joel Gratz is the creator of opensnow.com and is based in Boulder, Colo. Some data in this article was pulled from Tony Crocker’s excellent site bestsnow.net.
What about Alaska?