I had something come up yesterday which kept me away from the computer right when I was supposed to be writing an update, it was pretty late and I figured I’d wait through the model cycle to get some fresh info.
The storm track is clearly north of us, a disturbance to our north will brush by the northern 1/3 of the state Sunday-Tuesday and will spread light snow across those areas. On Wednesday or Thursday, it looks like a system or two are going to either pull down the western ridge or sneak in underneath it, this could lead to one or two chances of snow next weekend, the way the models have been behaving lately it may take longer.
You may have noticed that I have not talked a lot about the Madden Julian Oscillation (MJO) this year. If you want a nerdy explanation of the MJO click there.
If not, here is a good definition of the MJO, “The Madden-Julian Oscillation is a tropical disturbance that moves clouds, winds, precipitation, and pressure changes eastward around the global tropics about every 30-60 days. Typically, in the Northern Hemisphere the late fall, winter, and early spring have the greatest level of MJO activity.”
The MJO has been affected by the Indian Ocean Dipole (IOD) this Fall and Winter because the IOD has been in a positive phase. Much of the weather around our planet is affected by the Oceans and tropical activity. This positive IOD is responsible for the Australian drought and fires. The IOD is an area extending north of Australia (the Maritime Continent) over to Africa. Some of the warmest waters in the world are found here. The wind here typically blows from west to east in this region, when the wind changes direction and blows from east to west the IOD is said to be in a positive phase. The warmer waters have been blown into the Arabian Sea leaving colder waters and suppressing convection (storms) over the area. This has led to drought conditions in the area.
The good news is there are signs that the IOD is weakening which could bring relief to those areas before the end of January. What does this have to do with us? Sea Surface Temperatures in the tropics have a huge impact on our weather patterns, weather models take into consideration factors such as the MJO phases and IOD phases when they deliver forecast probabilities. With the positive IOD suppressing MJO impacts the models have struggled this year. When the positive IOD fades the MJO becomes more relevant and helps forecasters with longer range forecasts.
I seem to have gone off on a tangent there, but it is important to know that with weather nearly everything that happens somewhere else has some type of impact on our weather.
So the next five days should be quiet for most of us, then we look to the next week to ten days to start seeing some snow again which is being picked up in the long-range ensemble models.
Here is the Euro showing most of the snow in Colorado falling after the 11th.
Here is the GFS ensemble run (GEFS)
Here is the Canadian ensemble run
Even though a 15-day model forecast can be sometimes unreliable, you look for similarities in the models, these 3 model runs are pretty similar.
Speaking of similar runs check out the MJO forecasts for the same 3 models.
Phase 5 is not a bad place to be this time of year, interesting that the Euro shows us entering phase 5 in 6 days
The GFS shows us entering phase 5 in 6 days.
And the Canadian shows us entering phase 5 in 6 days even though this was an older forecast, it is the most recent I could find and it correlates well.
So while this boring weather continues I will continue to look ahead and see what awaits us. To recap, light snow in the Northern and parts of the Central Mountains late Sunday-Tuesday. Nothing in our area (at the moment) for at least five days, then snow should return to the area.