The key models I look at, the GFS, Ensemble and NOGAPS, are all showing a breakdown in the storm pattern for Northern Arizona. The jet stream forecast is for it to be directed more to the Pacific Northwest, taking the storms and the precipitation with it. This is the standard pattern I had foreseen for this winter.This leads me to think that the next week to two weeks are going to be mostly dry, or at least drier. Maybe we can climb out of the deep freeze for a bit.
But, wait. The Arctic Oscillation forecast is still to be in the negative phase. And the Climate Prediction Center posted the following January Outlook on Friday. (Just as a note, they posted after my Friday blog about the Arctic Oscillation)
In their 30-day outlook discussion they had this to say:
FINALLY, THERE IS THE ARCTIC OSCILLATION (AO) TO CONSIDER, WHICH UNFORTUNATELY CANNOT BE RELIABLY PREDICTED MORE THAN ABOUT 2 WEEKS IN ADVANCE. THE LATEST EXTENDED-RANGE GUIDANCE SUGGESTS THAT A FAIRLY STRONG, NEGATIVELY PHASED AO WILL CONTINUE AT LEAST THROUGH MID-JANUARY, AND LITTLE OVERALL CHANGE IN THE ATMOSPHERIC CIRCULATION. THE JANUARY 2011 TEMPERATURE AND PRECIPITATION OUTLOOKS ARE BASED ON THE LATEST, EXTENDED-RANGE NWP MODEL GUIDANCE FOR THE FIRST TWO WEEKS OF JANUARY, WITH CONSIDERATION OF TRADITIONAL STATISTICAL TOOLS, LA NINA COMPOSITES, RECENT TEMPERATURE AND PRECIPITATION OBSERVATIONS, AND THE EXPECTATION THAT A SIGNIFICANT, NEGATIVE AO WILL PREVAIL OVER THE EASTERN CONTIGUOUS US THROUGH AT LEAST THE MIDDLE OF JANUARY. BEYOND THIS, THERE IS SUBSTANTIAL UNCERTAINTY OF THE STATUS OF THE AO AND THE PREDICTED TEMPERATURE AND PRECIPITATION PATTERNS ACROSS THE EASTERN CONTIGUOUS UNITED STATES.
Not terribly different from my pondering on December 31, 2010. Looking at the Arctic Oscillation history and outlook, it has been mostly negative since the middle of November. This helped bring the storm track farther south for Thanksgiving. But, we had the warm temperatures in early December while it was negative. But, while we were basking in the sun, England and Scotland got hammered.
The current NOGAPS temperature and precipitation outlooks show a good chance for cold precipitation, maybe snow, in significant amounts this coming Friday, January 7 to England and parts of Scotland. While this may be a good analog to early December, we won’t see warming to above average temperatures. In fact, we will be lucky to hit average. This should keep the white stuff on the ground for the week.
Again, this seems similar to early December. There were two key components to having the storm track aimed at us in late December. A persistent, very cold low pressure system in the Gulf of Alaska and a persistent high pressure system to the south and west of southern California and the Baja Penisula. These features are mostly absent for the next week from most recent model runs.
A small low pressure system to the southwest is projected to move to the northeast across Arizona on Monday and Tuesday. This is a weak system with anemic moisture levels. We shouldn’t see much from this. At the end of the week, there is starting to look like there is a possibility for the persistent high and low pressure systems to form. This could set us up for a return to something similar to the Christmas and Thanksgiving storm patterns during the weeks of January 10 and January 17. Or, will the meteorologists return from Christmas break and tweak the models to tell a different story?
I had my son shovel our roof Sunday. I’ll probably replenish the wood supply by the front door today.