Pattern Verifying

We have been pouring through charts and analyzing data to verify the pattern. A lot of work goes into deciphering the cycle length. The length of the cycle is critical to accurate long range forecasts. Remember, every fall a new pattern begins and repeats, or cycles, until late summer. The old pattern dissolves and the new pattern becomes established. The new pattern, for this season, was sent back in September.

Recap 20-21 Season

This year‘s pattern will be longer than last years 46 day pattern. The 20-21 season had two main storms that I called Co-Sig 1 and 2, for cosignature storms. It also had a large inactive stretches that lasted for about two weeks. That helped us explain the pattern, because at FutureSnow, we knew when those stretches would occur and most importantly, when the active part of the pattern would return.

If you follow the Tahoe Daily Snow, with Bryan Allegretto, or the Colorado Daily Snow, by Joel Gratz, you’ve seen my comments. It’s not easy convincing people, especially meteorologists, that what they have been told, through years of school and certifications, is wrong. In the comments section of these blogs, I would make predictions and get grilled from other commenters. As the season wore on though, the tide began to turn. Thanks to the Pattern.

First Prediction

The fact that the weather repeats, will someday be taught. For now, you have FutureSnow. My first prediction, this year, was made on Bryan’s blog on October 4th for November 6th. I have never made a prediction this early. Last years first prediction was December 4th. The November 6th storm is just showing up on the models (over 350 hours out). It has the correct look, and most importantly the correct timing. Last time through it hit the PNW—a solid storm that tracked through Whistler down to Mt. Hood and across to Montana and Jackson Hole. It just clipped NorCal, Utah and Colorado. I am hoping with a stronger Jet that if will drop down further. Will keep an eye on this one. Mike

Last time through

Snowbird

Snowbird Ski Resort
Snowbird Snow Stake camera

The Trifecta is dumping precipitation across the west. Snowbird Utah is one of the early winners. Snowbird and Alta are a couple of resorts on my “Watch-list” for this season. Based on conditions, I pick out a few areas that I intend to visit.

California has been bone dry for quite some time. No rain, a lot of fires–just about 2.5 million acres burned in California alone. Not to mention the Lake Tahoe fire that charred a number of ski resorts. So this moisture is really needed.

This first map is the total precipitation for the water year, last year. If you look closely you can notice a typical La Nina pattern.

Total Rainfall for Calendar Year

You can see from the map where the rain fell. Compare the chart above to the water year prior below:

2020 Water Year

Now lets look at the moisture from the present storm system. Below are the last 3 days. This is an indication of the changing pattern for this winter. This storm, and a couple others, are going to fill in the gaps of previous years.

The next storm after the Trifecta is on its way, its a small wave that will hit the west coast Wednesday. A larger system will follow on the 19th. We will track these storms and keep you up to date. Thank you for spending a few moments reading the blog. As always if you have any questions please ask them in the comments section or shoot me an email to Mike@FutureSnow.CO.

Mike

Arapahoe Basin Ski Resort

Strong System

From the Toilet Bowl to Trifecta

A strong wave will approach Seattle and Vancouver BC impacting the coast overnight on October 8th. A rather large trough will develop and mature by the 10th with snow above 8,000 ft and rain below (generally speaking). It is still 250 hours out, but confidence is still high based on the last time the storm came through. This is one of three storms of this years cycling pattern and we will watch intently, like Peyton Manning watching a play with Eli, how this storm develops and spreads.

What we are looking at with this chart from Weather Bell is first, the circulation and flow around the hemisphere. It has an elongated shape due to the large ridge centered in Alaska. Often times last year when we had a similar setup, we would end up with an omega block, which would disrupt the flow keeping the energy north. If this continues to repeat it is good news for Northern California, Tahoe, Arizona and Colorado, as quite a few storms stayed north last winter.

I circled the cut-off system because in future cycles this won’t disconnect. That will result in strong storms in the Northeast. I don’t predict many storms for that region, because the flow pattern is harder to predict once it looses its grip through the “slick” parts of the country. Grip and slick parts? Now there are some scientific terms you won’t hear from NOAA. The mountains channel the patterns flow–grip. Once east of Denver its smooth for 1,500 miles–slick. Without the mountains to steer the current, the track, or flow varies by hundreds of miles. Making it hard to forecast. We accurately predicted the Nor’easter to repeat last year and it was posted on OpenSnow’s New England Daily Snow, by Jason Cordeira.

Now that we are getting closer to ski season I will post more frequently. If you have any questions, as always feel free to comment in the comment section or shoot me an email to Mike@FutureSnow.CO.

Twilight Zone

Introduction of the Pacific Oscillation

Pattern Transition

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.

Chart Evolution

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.

PO Index Mock-up



Upcoming Pattern Storm for Colorado

FutureHurricanes?

Hurricane Delta


Back on February 21st, the storm that is approaching Colorado for this coming Monday, was predicted by FutureSnow. It is part of the 46.5 day cycle length of this years repeating pattern. Monday’s storm has hit, on time, in every cycle with cycle 2 being the precipitation winner to date with 10” each at Vail and Keystone.
The 5th cycle began on April 8th. Below is the GFS snapshot of the 500 hPa charts for each cycle. You can see plenty of similarities and differences due to the different teleconnections. There are several things to compare and contrast but I’ll mention a couple. First the remnants of hurricane Delta are in cycle 1–the red dot near Washington DC. I mention this because one aspect of the repeating pattern is useful in predicting future hurricanes. You won’t know in which cycle they will come, but whatever hurricanes that occur during the new cycling pattern, their path will reoccur in the same date of the cycle, with similar locations the following hurricane season. So in this instance, hurricane Delta hit the Gulf of Mexico around Texas and Louisiana—so it will hit that same region this hurricane season during the same day of the cycle (day 4 cycle 1), so look for a possible hurricane hitting the Gulf June 3rd, July 20th, or Sept 4t: probability 75% +/- 5 days. Second, you can also see how the polar vortex, in cycle 4, effected the pattern. Look at the location of the polar vortex and how that changed the look of the chart. The PV is an teleconnection so this is a clear example of how just one connection can change the outcome.

Cycle 1
Cycle 2
Cycle 3
Cycle 4
Cycle 5 (4/12)

The next pattern storms will arrive towards the end of April. I will give you an update when we get a little closer. Thanks for spending time reading the FutureSnow/FutureHurricane blog, as always if you have any questions please ask in the comments section or send an email to Mike@FutureSnow.co.

Tahoe’s Up, Alta on Deck

The dry or boring part of the pattern it’s coming to a close and finally we’re moving into the active part again. The low pressure system spinning off the coast is headed towards Tahoe and will arrive overnight Tuesday. This should be a good kick-off to the active pattern and should bring double digits at least along the crest. Once the storm passes it heads towards Alta, right on time. Below is the energy and vorticity GFS.

As the low continues to move east, Washington and Oregon Resorts will get snow from the backside of the Low/Northwest flow. The system has occurred every cycle. With the last couple of cycles being stronger and affecting a larger path. The genesis of this system was way back in August when the new pattern was in its infancy.
Colorado is next with snow snow beginning on the 11th, right on time (predicted Jan 26th). Because of the position of the low, this could be the biggest storm that Colorado has all season. It’s been a down year because of the La Niña pattern, but I expect to finish strong in March and April to end the season at, or above average, like I predicted back in December.
The picture below is the next storm is spinning off the BC coast. That is the next system that’s going to affect Banff Lake Louise, Big Sky and Jackson Hole. This prediction was made on Feb 3rd.

4th Repeating Storm

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

Projected 500mb Z Vort

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.

Impossible Possible

Beaver Creek Colorado

I have known for a handful of years now that the weather repeats. I learned the theory from local Kansas City meteorologist Gary Lezak and expanded my understanding later with meteorologist Doug Heady about the cycling pattern. Then a natural progression occurred with first finding patterns in snowfall and later learning to read weather charts to make accurate forecasts. Last year I made a leap and started to get organized thanks to the prodding of Joel Gratz Founder and forecaster of OpenSnow, I put together a list of snow predictions and filled my photo stream with GFS snapshots, snow reports etc. I would shoot Joel emails pestering him with a snowstorm that I predicted and then when the storm would hit I would email him back “do you believe yet”. The answer was usually “not really” or something like “I kind of see what your looking at” but still skeptical. Larry Schick, OpenSnow Northwest and British Columbia forecaster had a great line “weather has no memory”. This guy worked for 20 years in Seattle TV as a meteorologist and now works for the US Army Corps of Engineers.

Below is the greatest long-range forecast ever predicted. Ok, I know it belabors the point to continually brag about forecasts, but it is not intended to be pompous, rather it is about this incredible force that is in the beginning stages of being understood.

Decoding the Chart

So about the chart: this was what I put together, Cycle 3 chart of predictions for January 25th through March 21. Last year was an 58 and a half day cycle. I ran out of room so I put day 58 at the top left. Yellow meant that I thought there would be a storm from the pattern based on previous cycles, Pink meant probable storms–official predictions. To me, the short hand was obvious, Squaw, Park, Heav, Banff–obvious mountains. Cry=Crystal, MH=Mt. Hood, JH=Jackson Hole, WB=Whistler, LL=Lake Louise, Kicking Horse (Canada–great place no crowds), BS=Big Sky, Alta and Vail. During the cycle I would record snowfall with the corresponding predictions. Below is the completed chart. The Date in in the box and the right upper corner the day of the cycle.

So looking at the chart on Day 3 was January 27th and in the yellow the predicted areas were Park City, Heavenly, then on day 4 Crystal, Mt. Hood, Jackson Hole, Whistler and Heavenly. So what I thought at the time was the system coming in would begin in the PNW, divide into a northern and southern track. the Southern track hitting California’s Heavenly sliding across hitting Park City with the northern track hitting Big Sky and Jackson hole. It was almost perfect, except that, as it turns out, Heavenly and the Tahoe region were not “in” the path of the pattern last year. I would later figure that out and take them off the grid–later though the cycle grew in strength (cycle path footprint expanded) and Tahoe would get a months worth of snow in a week right when the lockdown hit.

These area a few tools in my toolbox now. My photo folders are littered with screen shots of weather charts. It takes hours to pour through the charts figuring out the pattern, but it has its rewards of catching deep powder on occasion and always catching fresh snow on any ski/snowboard trip. I just got back from a trip to the PNW and also a Colorado trip. For Colorado, I booked this trip to take my son before his High School baseball begins–after which he will be busy until fall. We rode fresh snow at Beaver Creek and were lucky to get a mid-week rope drop off Birds of Prey lift, and our luck continued at Breckenridge getting to ride the Imperial Express lift, just opened for the first time of the season, after 3 failed attempts off the T-Bar–don’t worry buddy, it is really hard for snowboarders, you’ll get it next time! Then it was on to Crystal for the real powder chase.

Birds of Prey Express Lift
Steep and Deep at Crystal Mountain Washington

As always feel free to email me or ask a question in the comments box. I’m happy to answer! Finally, below is a chart of upcoming Pattern Storms predicted out until May. Probably won’t go out any farther than that, but Powder Days late in the season can happen. I rode a storm at Arapahoe Basin in late April a few years back that was on my top ten list of all-time trip lists–18″ of cold blower pow. I got white-out vertigo sitting on the Cornice Jump run. White-out vertigo is a really cool experience if it has never happened to you, the only thing you can see is white. You can’t get any perspective at all and you get dizzy. Luckily for me someone came and jumped off the cornice so I quickly followed close enough until I got down to tree line.

Prediction Grid Currently 85% Accurate

March and April Predictions

March and April Predictions

It has been an amazing year so far, FutureSnow has accurately predicted 23 out of 27 events, that’s 85%. That is really an amazing statistic because all of the predictions have been made at least 25 days in advance before any models are in range. The longest was 56 days for Colorado where Vail had 13 inches. There is an even longer prediction coming up, 67 days, for March 9-11th. I would love to end the ski season with 90%. This is not meant as a brag, I just simply interpret the data, it more of how cool it is to know when these systems will come through.

Cycle 4

The 4th cycle is under way. At the beginning of each cycle the storms favor the Pacific Northwest and Canada. This has occurred in each of the previous three cycles and GFS verifies same for the beginning of this cycle. The cycle is 45 1/2 to 45.8 days in length. I have adjusted the upcoming predictions by a couple of days to correct this offset.

When talking about the cycle, every year is different. Last year had a longer cycle, La Nina favors shorter cycles. Presently this La Niña is weakening, the Arctic Oscillation is neutral, the north Atlantic Oscillation is neutral, and the Madden Julian Oscillation is in phase 7 in the western pacific. All of these tele-connections influence the strength and path of storms. However, the framework, or structure of the storm path, remains the same throughout the spring and it weakens in the summer until it is wiped out in late summer.


February 27th Colorado Prediction

This forecasted storm was made on January 26th as I dove back into the history of the previous cycles. I missed this “pattern storm” and discovered it through a little forensic analysis.

History of the storm

Day 6 of last cycle, a small wave hit Colorado, followed by a large wave impacting the PNW. In cycle 2, again a small wave hit Colorado followed by a small wave hitting the PNW. In cycle 1 on day 7 a small wave hit CO followed by a large wave in the PNW. So when I decided to add this to the prediction grid I decided to add it on day 7, probably not a smart choice because it hit on day 6 twice but my thinking was it hit late on 6 both times and the day 7 storm it was during the day.
The GFS has this storm arriving at about 6 am on Thursday the 25th. This is actually right on time—if I would have been “on it” and adjusted the cycle length to reflect the uneven cycle (45 1/2-45.8 days).

FutureSnow CO Prediction

I have adjusted all future predictions by 2 days to correct the cycle to match the storm cycles. I am not going to update the existing storm forecast for February but the March schedule has been adjusted. Below us the updated predictions spreadsheet.

This Weeks Picture Challenge

Post your response in the comments section.