Tuesday, February 25, 2014

Sierra Snow

Monday, February 24, 2014
10:54 p.m.

99 closures of Snoqualmie Pass, 99-minute lift-lines. Take one down, pass it around, 98 closures of Snoqualmie Pass.

That's certainly what it's felt like for most of this month. We have been battered again and again by storm after storm, and our once measly snowfall, which was below 50% of normal in many places in our region, is now normal nearly everywhere. Folks, this type of recovery is amazing, and is akin to a hypothetical Denver Broncos comeback down 29-0 after Percy Harvin's kick return for a touchdown to start the second half. Of course, the key word here is "hypothetical." Forget Peyton Manning, it looked like Papa John was throwing those passes.


But what about Southern Oregon and California? As bad as our situation was, their situation was far worse. While we were 40-50% of normal, Southern Oregon was 10-20% of normal, and California was 20-30% of normal. Folks, this is frightening news for their summer water supply. The parade of storms to recently hit us was primarily aimed in our direction, and the mountains of Southern Oregon and California did not get nearly the amount of snow that we got.

http://www.wrcc.dri.edu/snotelanom/basinswen.html

The picture above compares the amount of water content in the snowpack now to the average for this time of year. As you can see, it is right about average in our neck of the woods, decreasing as you go southward. Even the 60s in Northern Oregon aren't too bad. But by the time you get to Medford in Southern Oregon, the snowpack is pitiful. Things get marginally better as you go to the Central Sierras, but not in a statistically significant manner - you go from 35% of normal to 40% of normal. Things are just downright despicable in Arizona and New Mexico, with several stations in the single digits. One station doesn't have any snowfall at all. In a manner similar to Kam Chancellor blasting Vernon Davis into the next area code, these guys are gonna be in a world of pain if they don't get any snow.

But, it just so turns out that they will get some snow! We'll get a nice little break from the action, and although I must confess that I'd like to keep the snow a'comin here in the Cascades, I've got some California Love embedded in me as well, and I'd like to see those guys be blessed with the same good fortune that we have had. They WILL NOT have the same never-ending, atrociously awesome series of storms that we've been fortunate enough to have, but they will get a foot or more in the Sierras. When you are this far below average, a little bit of snow goes a long way.

Valid 04:00 pm PST, Sat 01 Mar 2014 - 120hr Fcst:     http://www.atmos.washington.edu/~ovens/wxloop.cgi?mm5d2_x_msnow72+///3

As you can see, the Sierras will get more snow than California. Two systems will roll through... one during the Wednesday-Thursday time frame (pictured below)

Valid 07:00 pm PST, Wed 26 Feb 2014 - 51hr Fcst:   http://www.atmos.washington.edu/~ovens/wxloop.cgi?mm5d1_x_pcp3+///3

... and one that will stall off Southern California Friday morning through Saturday evening. This system will deliver some snow to Arizona and will bring that SNOTEL base above the 0% of normal mark. It will deliver some snow to the far northwestern end of New Mexico, but the places in the south - the places that really need the snow - will stay dry. Check out the 3-hour precipitation below to get a look at the structure of the storm, and then check out the snowfall associated with it.

Valid 04:00 am PST, Fri 28 Feb 2014 - 84hr Fcst:   http://www.atmos.washington.edu/~ovens/wxloop.cgi?mm5d1_x_pcp3+///3

And here's the 72-hour snowfall.

Valid 04:00 pm PST, Sat 01 Mar 2014 - 120hr Fcst:   http://www.atmos.washington.edu/~ovens/wxloop.cgi?mm5d1_x_msnow72+///3

Why are we having such a sudden southern shift in our storm track? Well, instead of having zonal flow off the Pacific, our pattern has shifted to one where we now have a trough of gargantuan proportions off of Southern Cali. Some precipitation will even make it to Baja California. Pretty amazing shift for a couple days if you ask me.

Valid 04:00 am PST, Fri 28 Feb 2014 - 84hr Fcst:   http://www.atmos.washington.edu/~ovens/wxloop.cgi?mm5d1_x_500vor+///3

Enjoy the break! Things look to stay calm and chilly for a while. No big storms or bluebird skies on the horizon. The European model is teasing us with some snow in the long range, but it's much too far away to be putting any faith in it.

Charlie

No comments:

Post a Comment