Buena Vista, Colorado
Paddling Since: 2005
Join Date: Jun 2008
Certainly off to a good start. Sounds like there is another decent storm on tap for this weekend and the long range forecast sounds good. I like to use Snowforecast.com for forecasts more than 1 week out:
LONG RANGE FORECAST DISCUSSION:
7 day to 2 week forecast - 10 to 19 December, 2013 - Tuesday (10th) should be tranquil with mostly sunny skies and great conditions as temperatures remain cold enough to preserve all of the snow that just fell. At that time, we expect a shifting pattern, as east Pacific high pressure ridging that has been a very persistent feature this fall breaks down or is undercut by the jet stream, and the storm track-jet stream cuts more across eastPac waters and into the west coast, with a more zonal (fast moving, west to east) pattern and fast moving storms possible into mid December and beyond. These storms would favor California, Lake Tahoe resorts specifically and the northwest US, with drying and weakening as these storms move into Utah and Colorado (some of these clip Colorado mid to late next week (11-13th) with mostly light to moderate snowfall potential. Either way, the pattern stays pretty busy across the west, and this is expected to be good for snow pack and conditions as frequent storms keep the snow coming. CM
Longer Range Outlook
Last winter we had a La Nina SST pattern in effect, and our weather was drier than average across the southwestern US, and near to above average snowfall was recorded across the Pacific Northwest. This does not include December, which was near to above average in precipitation for some parts of the southwest US. Christmas and through the rest of the season was pretty dry for most areas including Tahoe.
We do not expect a repeat of last season, this season...
As of now, November 2013, we are officially being affected by an ENSO-Neutral, or La Nada Sea Surface Temperature pattern across the Equatorial Eastern Pacific (SSTs near to slightly below average).
Current SST pattern- La Nada
The larger time-scale SST pattern in place right now is a cool phase PDO, or negative PDO, which stands for Pacific Decadal Oscillation. This is a more long term pattern (decades), and it has made any recent years El Nino SST patterns weaker. All of this means a couple of things for us. We do not have an El Nino or La Nina SST pattern, so nothing is as clear cut as either of these can be in terms of prevailing weather patterns. A wet Southwest US is not likely (El Nino), and a dry pattern for the southwest US and wet for the Pacific Northwest (usually the case with La Nina) is also unlikely, so we are left with the many potential scenarios in-between, but overall we think all areas will see better than average snowfall.
We expect the ENSO Neutral, or La Nada pattern to continue through at least mid-winter, with a possible trend toward El Nino in the late winter/ spring/ summer of 2014. East Pacific high pressure ridging will be a pretty persistent feature in the early season, possibly through December and into January, with colder than usual storms moving in out of the northwest and not as much out of the west, off the Pacific, for plenty of cold blasts and storms hitting the Rocky Mountains, and the anything goes cut-off low pressure systems also a common feature this winter, through December and into January.
Cut-off low pressure systems, though a bit more dicey and hard to predict, can provide many areas across the southwest US including northern Arizona, northern New Mexico, and southwest Colorado with good dumps of snow, so with these storms a good possibility, we could still do pretty well in these areas. Faster moving clipper-type storms are also expected to hit northern Colorado and Utah, Wyoming, the northern Rocky Mountains and on through the Pacific Northwest with some good dumps of snow as well.
-->After the Christmas-New Year rush, the La Nada may start to wear off, being replaced by a weak El Nino SST pattern. This means we could see a strengthening jet stream across the west and eastern Pacific, and increased moisture in general for late winter snow storms as they move in more directly off the Pacific, late January-February and through April. We will keep this outlook updated as more information becomes available.
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