Every year at the autumn equinox, September 21, the sun sets at the north pole and all that remains is twilight, until the first week of October. Then it becomes perpetual darkness for the winter. When the switch is flipped from twilight to perpetual darkness, a switch is also flipped beginning the new weather pattern for the next 12 months. This is exactly what is occurring now. We are beginning to see the new pattern, and along with it the new cycle length.
Although personally I have been using the cycling pattern for eight years now, it wasn’t until three years ago that I started getting organized by creating charts. They were crude at first, but they worked. I printed off blank calendars and pasted a couple together to create my first “cycle length” chart.
By using this chart I could track storms and snowfall amounts, then use the information in later cycles. The cycle length for the above chart, was 58 1/2 days for the 2019/20 season.
For the 2020/21 season, I started using spreadsheets. The spreadsheets were much easier to track from cycle the cycle. It also cut down on simple mistakes.
Pacific Oscillation PO
Now I am using XCel to create a powerful new tool that will help with forecasting. I am calling it the Pacific Oscillation (PO). The PO will index the Pattern similar to how the Arctic Oscillation charts it’s daily variability in winter. I will publish the PO index right here at FutureSnow. A good example of how it works will be forthcoming, however I can tell you that the storm that just came through Colorado, showed up very well on the index. The index will track the strength of the cycle against the other teleconnections.
We are entering the active phase of the pattern with Saturday nights Storm beginning at the Lake Tahoe region. Every cycle there are a different lineup of forces (AO, NAO, MJO, ENSO, etc.). Those differences relate to the outcome shown on the 500mb charts. Let’s look at those charts of this years La Niña dominant pattern. 45-46 day pattern
You can see that these charts have a similar look to them. The differences, again, are the strength of the different teleconnections. All of these snapshots have a second round of energy following the first round come with the exception of the October snapshot. The pattern was still developing in October. Tomorrow will get into the next trough that sets up 13 days after this one.
January 3rd, or 46 days ago, we predicted the week of storms that will be hitting the PNW (Crystal MT) this week. We specifically used Crystal because it centered on the storms that have occurred in each cycle. Sometimes the Oregon mountains were hit, and other times the British Columbia mountains were hit, but Crystal was hit each time. GFS looks solid for this week. Next up is Colorado, Feb 27th, this has been a small storm that has teetered on day 6 and 7 of the last 3 cycles. Its quite possible this could be a technical bust for my prediction because I only have a day as a variance, but I wanted to get this storm into the forecast because I missed it in the first two cycles.
I published the spring break forecast a few weeks ago so you can check it out here.
There are so many examples of Recurring Pattern that happen each year. This is just another one of them. If you look at this present storm and then you look at the storm from 46 days ago they are almost identical. Meteorologists, climatologists, atmospheric scientists all miss this. We have cycles everywhere, oscillations, etc. and yet they still miss it. Why, it looks like it’s so easy? It’s not, it’s very subtle. Gary Lezak, a leading meteorologist on the subject, once said to me “the artist will see the pattern much faster than the scientist”. That is so true, it took me years just to convince Joel Gratz, of OpenSnow.com—and he’s still skeptical. Doug Heady, an incredible expert and Founder in this field says, I’m paraphrasing, even when you know the cycle length, there is so many variables that go into each and every storm. That’s why it’s so hard to understand. Someday though it will be understood and modeled.
Ok so let’s dive in. Look at these two pictures. The flow, the storm, the ridging all match. Now this doesn’t happen very often. But when it does it makes you understand that the cycles can set up the same.
The flow is signified in blue, the red squiggly lines are the ridges, and the green circle is the particular wave, or storm coming on shore. In the December snapshot you can see right where the polar vortex is going to go. Fits right into the puzzle. When you look back to the teleconnections in December and look at the teleconnections today, they are similar. When all the variables lineup the same the outcome is the same—roughly.
The storm that I have forecasted for February 18th is on the way. The last few storms have been trending about 12 hours early, that is because the cycle length is about 45.8 days and we are in the tail end of cycle 3.
Here is an update on the bombcyclone, back on January 1 I posted that the bomb cyclone that was hitting Alaska at the Aleutian Islands would return on Presidents’ Day. Well it’s Presidents’ Day and the storm is right on time. Not a bomb cyclone this time but a nice low. It’ll come back around April 3.
We are in the middle of the predicted storm and the next storm system is coming through on the 7-8th. The winners so far are the southern Mountains of Colorado and Lake Tahoe region. The storm for February 7-8th is showing up on GFS and looks correct, meaning the models have the correct solution. This is one of the features of the Cycling Pattern is you know when the models are right or wrong based on the template of what has happened before. The influences (AO, NAO, PNA, MJO etc) are different and have to be factored in, but the general picture is similar. The last time this system came through was on day 33 and 34 of last cycle which was December 23 and 24th. Canadian resorts were favored with Kickinghorse reporting 13”, Banff 16”, Crystal Mountain 9” and Mount Hood 8”. Alta had a great powder day of 18+. Tahoe did get snow but not very much Squaw had 4”. The Colorado resorts were all in single digits with Arapaho Basin and Breckenridge reporting 6”. this time around the cycle is stronger so I expect the totals to be higher. Stay tuned.