Heat Miser Going on Vacation; Cold, Snow Chances?Last Edited:
Well here we are starting the second week of January off on a cold note, granted, we will warm up again briefly tomorrow but the medium-range looks much healthier for cold air that is did at this point last week. Encouraging for Winter weather lovers for sure! I've come to learn this Winter that were are actually A LOT of people who want a continuation of the mild pattern we've been stuck in. In fact, I may be in the minority when it comes to wanting cold and snow. I've received many messages over the past couple weeks asking me why I'm so adamant about a pattern change. My answer is simple: I love Winter. I love extreme weather and I love when what's supposed to happen in a given season, actually happens! I don't have any sort of agenda, I just want it to be cold and snowy in the Winter! With that said though, as a forecaster I need to be cognizant of the facts and observant of what's going on around us.
I put out my Winter forecast back on November 1st as I do every year. So far, I'm happy with how things have gone. I'll admit the past 10-15 days have left me with even shorter nails as the things I wanted to see come together DID, but the outcome hasn't been one I was anticipating or frankly prepared to see happen. The one thing I try to stress is the fact that forecasting long range is a completely different animal than trying to nail the 7 day forecast down. There are variables that you look at, sea surface temperature profiles and anomalies of years past that acted in a similar manner to project forward. It's a long arduous process that has left me burnt in the past, but it's rewarding because you learn something new each year. In meteorology you NEVER stop learning and that's why I love what I do.
OK enough blabbing. Let's get down to brass tacks and try to wrap our heads around what's going on here. Clearly it's been warm. It turned so by mid-December. That WAS anticipated. We knew a period of mild temps was coming that would last 2-3 weeks. It lasted a little longer than I wanted it to as I thought early January would see the flip to colder weather but it's going to happen and that's all that matters. I was wrong about when it would get here, no way around that. It happens. But why? It all has to do with the pattern. Let's go thousands of miles away and take a look at something going on around Australia. It's called the Madden Julian Oscillation. There are 8 phases that impact our weather here at home. We were in phase 8 and 1 in November when things turned severely cold around Thanksgiving but then migrated into 3, 4, stalled in 5 for awhile and are FINALLY starting to see it back in cold territory. The MJO has to do with tropical convection and its influence on the overall pattern. Over the past few days the MJO has looked more and more favorable. Some models bring it into the null phase. In the weather community it's called "The Circle of Death". When the MJO does null, it doesn't mean the death of Winter or the prospect of storms, it simply means that the lack of tropical convection has no impact on our pattern. That's all. Some of the biggest blizzards have occurred with the MJO in null. Doesn't bother me. What DOES bother me is if it went back into 5, 6 and 7.
Looking at the sea surface temperature anomaly I've outlined 3 regions I want to talk about briefly.
1. Cold water west of Australia. This has been in place for a couple months now. Colder water inhibits convective activity. It promotes high pressure. This helps the Southern Oscillation Index go negative.
2. Modoki El Nino. You've heard the term many many times before. El Nino. It means the water along the equatorial pacific is warm relative to average. We had a big El Nino in 2015-16 which led to a very mild Winter overall. Not every El Nino is created equal though, so the outcome of each will vary. This year's is much more central or west based which has implications on the pattern downstream. I see no reason to back away from that idea now.
3. Warm Blob. The warmth in the Gulf of Alaska has backed down a bit from where we were a couple weeks ago because of low pressure sitting there churning up the water. It still remains warmer overall and will likely regain some warmth as soon as that low is forced out. That warm blob is part of something called the Pacific Decadal Oscillation. It is a tad bit more favorable today than where it was last week, but I'd still really like to see the water in the pacific cool down more to solidify the pattern.
In addition to the Madden Julian Oscillation, we look at the Southern Oscillation Index (SOI). Up until late December, it was behaving as though we were in a La Nina Winter with lots of low pressure and positive values. In order to get where we want to go, we need high pressure and negative values overall. The drop began around the 28th of December and is continuing. We went very strongly negative a couple days ago and are now sitting around -4 but don't worry, these values fluctuate. As long as we are more negative than positive, it's favorable. It will be interesting to see where this goes over the next couple weeks.
Now let's look at our upper air pattern at the 500mb layer of the atmosphere. We want to see where our jet is. The past few weeks have seen ridging (lift of the jet) in the east and injection of mild pacific air into the pattern via that low in the Gulf of Alaska. That will slowly change. The optimal setup is to have a deep trough (dip in the jet) southwest of Alaska, a strong ridge in on the west coast and a trough in the east with high pressure over Canada. I like the look of where we go on both the CFSV2 and the EURO ensembles. I never thought I'd say I like the CFSV2... It's a very inconsistent model but I must say it has gained some respect from me this year as it had the warmth for late December into January pegged pretty well. Anyway, take a look at this....
Red is high pressure and ridging. Blue is low pressure and troughiness. This is for the month of February, which, I believe will be a phenomenal month for us in terms of cold and snow.
Here's the EURO ensembles taking us towards the end of January. Very similar. The only thing I'd like to see change? See the blip of blue in Canada on the EURO? We want that replaced by high pressure so the trough can build deeper in the east. Time will tell.
With all these players lining up, the question becomes "WHEN WILL WE GET SNOW?!"... and the answer is "it will come". In fact, we may have a chance as soon as this weekend. I remember a couple weeks ago I said mid-month looks to be the time where cold and snow is more favorable. I'm careful with what I say on-air because a lot of the people watching don't care to come here and read my explanations. Yes - there's a decent signal for a storm by this coming weekend. Will it come to fruition to the point where we actually see snow for everyone across the board? It's simply too early to tell. I can say measurable snow is becoming more likely and if I had to call it right now? I'd go with a 55% chance. Track will clearly determine if the snow is just in the big cities or if it can make it down to the coast too.
The difference with this upcoming storm is the fact that we will have cold air available. High pressure sets up to our north and northeast which dams the cold in. Even if we see rain, there would likely be snow at the onset. This is what we want! Here's a look at the 0z run of the GFS. It puts the storm almost in the perfect spot for widespread snow for all. We will have to see how it plays out. I'm not going to try and tackle specifics yet. I'll wait until Wednesday to first see if it's coming and then by Friday start to hash out the specifics.
Here's how I think things play out over the next 30 days...
- Period of cold air arrives
- Potential for 1 or 2 snow events inside the 15 day mark
- Moderating temps for a few days
- Bigger shot of cold, more sustainable by the end of the month.
I am on vacation next week. I'll be in the Keys. I'll still keep tabs on the weather and update as needed... I'll be working the first couple days off if that storm does indeed impact our region. We will re-evaluate the Winter forecast when I return. It's important to form an idea and stick with it until it's certain you're wrong. I don't think I will be wrong though. If I DO miss? Oh well. At least I'm not Cody Parkey from the Bears ;)