Saturday – 19 Dec 2020 – 10:15am
Pagosa Weather is halfway through December and it has been an interesting winter. In the mountains, Wolf Creek has been hit by a TWO foot, THREE foot, TWO foot, and TWO and a half foot snow events for a total of 135”! Wolf Creek Ski Resort was the first in the lower 48 to open, the first to have 100% of acreage open and currently has the 3rd deepest snow base behind Mounts Baker and Hood. As of today, Wolf Creek has a Summit depth of 76” and a midway depth of 71”. Wolf Creek averages 430” a year so they’ve had 31% of their annual snow fall before Christmas.
Snotel sites Upper San Juan and Wolf Creek Summit sit at 109/108% respectively.
In the valley areas, we only had about 5” of snow in November but our total precipitation was a little above normal. So far in December we’ve had 11” of snow. The December average is 21 inches. Based on Shawn’s forecast, we’ll struggle to get to average unless the last few days of the month get more active.
Our team at Pagosa Weather has identified a trend in the long range models. The super long range models hint at a storm cycle, and then the long range models slowly degrade those cycles. As the events come into focus in the medium range models, they tend to strengthen and take a more favorable southerly track. This has been a real challenge for us to give you an accurate forecast.
What is going on?
If you read my winter outlook “Pagosa Country Winter Snow Outlook” on August 29th, you’ll know that this is a La’ Nina winter which means we usually have below average precipitation. Wolf Creek does not look like it is having a La’ Nina winter at all! I have a theory that may explain why we are doing a little better than expected…
My theory is two part…
One, I believe that the long range models are being tweaked to add a La’ Nina bias. It is not unusual for a team of forecast modelers to adjust the algorithms of a model under unusual circumstances.
Two, if we look at the current La’ Nina event, the coldest waters are further out in the Pacific as opposed to hugging the South American coast line at the equator. Note: the colder water suppresses normal storm activity and this throws off the normal storm cycle around the globe.
I believe that this has moved the normal La’ Nina dry line a few degrees south into New Mexico rather than to our north where it normally is. I’ve reached out to a few of my meteorological scientists friends to confirm my theory. I’ll do another winter update at the end of January and share with you what I have found at that time.
As you can see in the Time series Sea Surface Temperature, the water closest to the coastline (1 & 2) is warming slightly. This could indicate that La’ Nina is weakening. The long range forecast is to return to neutral conditions in March.
Finally, shows that the super long range model looks good going into January.
See current La’ Nina advisory for more details: https://www.cpc.ncep.noaa.gov/…/enso…/ensodisc.shtml–
- Arleen
