ST. LOUIS, MO – The 2017 Fall brought some wild temperature rides and some interesting moisture patterns. Fall gets us ready for the big three months of long range forecasting, the winter season. The questions of cold and the questions of ice and snow dominate. But also we ask, what about a white or green Christmas? Every day is fun to forecast in St. Louis, but winter is a little extra fun. So off we go with a look at December in St. Louis.
With some form of la Nina in play, I'm expecting this December and much of the upcoming winter season to be quite different from the last two winters in the St. Louis area. The problem is that there is a ton of uncertainty and that is not a good thing when putting together a long term forecast. I'm thinking we are going to be on the edge of not only of a very cold air mass to our north and northeast but also a rather mild air mass to our south. So there is a high risk this could swing either way. As a result, like the Fall, there will be some pretty solid winter temperature swings this December. I am thinking we will have two to three rather strong cold shots, the first one arriving rather early in the month and another cold shot just in time for the holiday. Any breaks in the cold pushes will be December breaks, more of an easing of the chill from time to time. As a result, I think when we add up the numbers for the month temperatures will be a little below average. Overall, it’s a cold start to the winter season and the heating bills and the wood pile will get some work outs. I’m not expecting record cold nor am I expecting record warmth.
We move on to the moisture patterns for the 12th month of the year. The la Nina pattern that will be setting up will create two in power storm tracks. The first will be the northern run that will try to sneak a few Alberta clippers into the middle of the nation. The core moisture will stay to our north, but this track paves the wave for the three cold snaps that I’m expecting. The other track is the southern kick up, but I think that the main focus will be from the lower Mississippi Valley into the Ohio Valley and to the northeast. Every once in a while this track can get us with a backside snow, but my thinking is that this track will hold the core moisture well to our south and east this December. So these are not the Texas panhandle type storms that are the grand-daddy storms for the St. Louis area. With that said, I think we could have a few little snows with the clippers and maybe a backside snow that brings a pretty good accumulation. When the month is over moisture, rain and snow will be near average and snowfall near to slightly above average.
December also brings up my toughest forecast when it comes to the long range: What is the weather for Christmas? Of course, any one day forecast in a long-range outlook is more than tough, but we have to focus on my thinking for the month. With an active northerly storm track and southern systems that could nick us plus some cold snaps, I have to put it on the table. I am going with a white Christmas this winter season.
Things to look for December
- The great horned owls begin courting...you can hear them hooting on the long winter nights.
- Check out the sky...easy to spot the winter constellation Orion
- Bald eagles start to arrive in good numbers
December 2017 Highlights
- See-saw temperatures run for the entire month with three rather strong cold snaps from the north...temps a little below average
- Moisture patterns are not in solid focus but thinking we will see some snows this December...rainfall near average...snowfall slightly above average
- May be going way out on a limb...but let’s think a white Christmas for the St. Louis area
Most will agree, January in St. Louis is one tough weather month. Even the snow bunnies can get down. The month seems to go on forever. The holidays are over. The nights are long and the days are short and we typically deal with a fair share of wind, rain, ice and snow. But Mother Nature many times will toss us a bone in the form of a January Thaw, a nice mid-winters break. But with or without the thaw, January is the prime time for cabin fever.
The two key features going into the New Year will be la Nina feature, a rather large area of cooler water in the Pacific west of Australia. Yes, worldwide ocean temperatures are a critical feature to forecasts. Remember, not all el Niños or la Ninas are the same, each one is a little different. Another major concern a term called "polar blocking." This raises big questions of where the cold air will flow and, in turn, where a warm up will take place. Oh boy, that’s a headache in January. So let’s take a stand. I do think some blocking will happen in the Arctic but rolling the dice that that does not happen until mid-month. So let’s think January has a split personality. The first part of the month will be on the cold side with temperatures near to a touch below average. I am not expecting any records. Then the blocking will shove the cold to our east and northeast allowing warmer temperatures to take over for the second half of the month. So I am thinking there will be an extended January Thaw for the second half of the month. When the month is all done, temperatures will be a little bit above average for the second month of the Winter season.
This will be a weird month for the moisture patterns. The colder first half of the month will bring a few Alberta clipper type storms, with the core energy running to our north and northeast. But it is close enough that what moisture we do see will mainly be in the form of snow. Then as the temperatures warm for the second half of the month and a blooming of the southerly storm track, we will see an uptick in the stormy action. Snow bunnies, I can already see the sad faces. Warmer temps and the southern track means mainly rain, maybe some ice. But it is rather active, so when the month is done I think snowfall will be near average and rainfall will be above average.
Things to look for in January
- Red-tailed hawks are perched along the area highways looking for food
- Watch for chickadees feeding up and down the trees
- Beavers begin breeding this month
January 2018 highlights:
- A month that will have a split personality... The first half of the month cold and the second half of the month warmer
- There will be a January Thaw...maybe an extended thaw...second half of the month
- Moisture will also be split...snowfall near average and rainfall above average
Time for February, the last month of the three months of winter. Of course, cold and snow can happen into April, but in February we start to think we have turned the corner. Not so fast my friend, this is a month that can quickly knock those thoughts into the ground and reminder us winter still has plenty of action up its sleeve. We can have plenty of cold and, second to March, it is know for its snow making machine.. Strap in, let’s take a look at the month of February.
This will be an interesting month over the St. Louis area. There are some conflicting signs and the bust potential is a little higher than what makes me comfortable. But that never stops me. First for temperatures, the set up is much like what I’m thinking for January with la Nina and a blocking pattern. The timing is the key. I think the first half of the month will be on the warmer side to match the end of January. Then we’ll see another flip for the second half of the month, back to the cold side. No records, but I am certainly not thinking about any early Spring weather. There should be some rather strong Arctic pushes for the last two weeks or so. The heating systems will get a late winter work out as the swings continue but with the 50-50 split I’m thinking temperatures will be just about average. It’s Winter…cold, but not intense when looking at the entire month.
The expectation of "flipping" temperatures will result in more interesting weather in the month of February. The southern storm track will be in play for the first two weeks with the focus on the wet being to our south and east. But southern systems always have to be watched for something unexpected. During the last half of the month, the southern stream sinks south and the northern track is alive and well once again. This is the Alberta clipper track, most of the time this is a cold and dry flow us, a winter northwest flow. But as in every season, we know the saying: "Never trust the northwest flow" and these northern systems will bring at least some light snow. If enough southern moisture works in, a little bigger accumulation will be possible. Just lots of questions on that link of moisture and cold air. When it’s all said and done, rainfall will be near average and snowfall will be below average for the month.
Things to look for in February
- Red flowers of the Silver Maples swell with the first warm spell
- Chickadees begin to sing...the first bird songs of the year
- Look for robins returning in large flocks
February 2018 highlights:
- Another 50-50 month when it comes to temperatures...two weeks of pretty easy to take readings and two weeks of cold...but no record cold.
- Two active storm tracks...the southern flow in play for the first half...core moisture stays south and east
- The northern, clipper track in play for the second half...some light snows with the overall dry cold pattern
This will be an interesting Winter to watch unfold and to forecast, but that always makes it fun. There are some clear cut signs but there is also a lot of haziness in the atmospheric elements too. So, a warning, there is some bust potential on the table but that is the risk I take. So, hang in there. Spring is around the corner, but that is for my next long range forecast.