ST. LOUIS, MO (KTVI)- Winter is still doing its thing over the St. Louis area and there is more interesting and tough forecasting ahead. The three months of winter may be ending, but spring struggles are here. The key to early spring in St. Louis are wild swings, some that give up hope that spring is near and some that remind us that winter is not ready to let go. The great St. Louis weather ride continues. So let’s get this started with a look at March in St. Louis.
March 2017
Though March can really have a split personality with a battle between winter and spring, more times than not winter still has the upper hand. Those swings are always the big concern in the month of March. The overall pattern is a neutral, no el Niño and a very weak la Niña at best. Though I think el Niño will be making a comeback this spring and summer, I don't see that taking place in March. As a result, let’s stay the course and expect few extremes this month. Not too hot, not too cold, but also not really right. Temperatures will hold close to average for the month and that will keep things on the cold side. As a result, we can't rush the season. Hold back on the spring cleaning, garden preparations, and limited time to be outside. Even though the days are really getting longer, the sun angle is still rather low keeping the chill in the air.
Will we have some mild weather? Of course, that is all part of the swings I’m expecting.
The good side of an average temperature in March is that it will slow the trees budding and slow the allergy season. But the tree pollens are waiting to attack, especially by the end of the month when warmer temperatures will be taking control. I am thinking limited warmth early and mid month and then a little better in bonus warmth for the last third of the month. The hard core cold this month will hold to our north and east. Our soil temperatures will stay on the low side, so the early spring commercial planting will see some minor delays.
On to moisture and to get the spring season going March can bring some very impressive snows to the St. Louis area. In fact, the biggest snow on record is not the Blizzard of 1982, but a major snow in late March back in 1890 when more than 20 inches of snow fell. So what about snow in March 2017? I’m not overly excited. I think we will see some snow, with the focus on the first 10 to 15 days, but I’m not expecting much in the large scale patterns as the core storm track holds to the south or well to the north, much like the winter season. Maybe some snow but things look limited at best. What about rain and storms. We start to think about severe weather in March, but that is all we will be doing this year. I think the severe storm and tornado season will stay in hibernation. The month will be below average for rain and snow. That is good news because the low rivers and streams will stay low, so I am not concerned about March river flooding this year. But that will become a growing concern going through the Spring forecast
Things to look for the month of March
Red maples begin to bloom
Ticks start to appear and in the middle of the month--a real sign of spring
Purple martins arrive
Major Points of March 2017
The winter roller coaster continues and will last the bulk of the month.
Temperatures end up close to average but remember that will be on the chilly side.
Moisture will be limited...below average for both snow and rain. Limited storm risk and no flooding concerns.
April 2017
April is one of the great months when it comes to weather in St. Louis. It’s all about variety and variety is king this month as winter lets go and spring starts to flex its weather muscles. This variety can create just about anything, snow, rain, wicked thunderstorms, flooding, always the risk of tornadoes. That makes it a tough month when it comes to forecast, but that’s never stopped me before.
I think this April is going to an interesting and rather challenging month, not only in the long term but also in short term forecasting. Like the start of the baseball season, I see some curve balls in our future....maybe even a slider from time to time. This April, much like last year, will bring a solid jump into the spring season. The large scale pattern is still neutral after a weak la Niña and still no come back of the el Niño pattern I’m expecting this summer. But that neutral pattern does mean trouble on the horizon.
The big thing this month will be above average temperatures. In fact, they could be well above average when we add up the numbers. The grass, the trees, and the flowers will explode so get ready for another wild allergy ride. Oak is not my friend in April. The tree pollens will be in full force all month long. It is April, so there will be some cool weather but nothing is going to get locked in. The major trends will be very pleasant days, even warm at times by the end of the month. Nighttime temps will be chilly early, but by mid to late month the nighttime lows will be pretty easy to take. We will say goodbye to any winter chill. The outside fun will rocket to the head of the class and that also means some great baseball weather, not only for the Cards but also the growing little league schedules.
My real interest comes with the rain and storm patterns this April, remember the curve balls the month could toss at us. Well my confidence is little low on this part of the long range. Why? It’s that neutral large scale pattern, or a lack of direction, so this is a month that could swing into drought or be something completely different. But I won’t sit on the fence. I will take a stand and say we are going to the wet side this April.
As I turn to the Pacific Decadel Oscillation (PDO), this is climate pattern similar to the el Niño/la Niña pattern. called the ENSO. But the PDO varies over a much longer time scale. It is now turning negative and can stay in the same phase for 20 to 30 years. In contrast, the ENSO flips around every 6 to 18 months.
I know you’re asking, English please? What does it mean for us? I think rainfall will be above average for the month. But my concerns are twofold, both dealing with thunderstorms. The pattern should bring an up-tick in strong to severe storms with growing outbreaks going through the month. I think we may see 4 to 6 weather events, especially mid to late month in April. That is slightly higher than average. Every outbreak brings the works, heavy rain, hail, wind, and lightning and that will lead to some flooding, flash flooding on the small streams and creeks and moderately concerned about some flooding on the larger rivers. However, my main concern is a focus on tornado weather from the St. Louis area and points south down through Arkansas, Louisiana, east Texas, and Oklahoma. We are on the edge of this tornado uptick, but too close for comfort and we really need to stay alert with the short term forecasting
Things to look for in April
The tent caterpillars start to appear
Hummingbirds start to return...they are called hummingbirds because they can't remember the words
Robins and other birds start to build their nests
Major points for April 2017
Spring jumps to the head of the class...temperatures running above to well above average.
Expecting an active wet weather pattern...the focus on strong to severe storms with flash flooding and some large river flooding
Main concern is an uptick in tornado weather...the potential is moderate to high
May 2017
May is another month of seasonal swings as we work out of spring and start seeing hints of the summer season. That is what is so neat about spring in St. Louis, it brings winter, spring, and summer in only three month. May has that bad-boy image, a rock and roll month known for its big-time thunderstorms along with heavy rain, flash flooding, river flooding and our trade-marked severe thunderstorms. But it’s also a month of fantastic weather that gets everyone outside.
This May is going to be all about spring with a little hint of summer. Overall, we will see some excellent temperatures from start to finish for the month and from day to night. Thinking the month will be mild to warm with temperatures ending up well above average and a summer surge knocking at the door for the end of the month and Memorial Day weekend. But that brings us to one May element I put on the table almost every year. It is known as the "Blackberry Winter" or the "Dogwood Winter." It is a cold snap that happens around May 9th, 10th and 11th. It may be tough to see it this May, but I hate to turn my back on it. Let’s keep the idea going, just not as strong as the last few years. Why the name? It is typically is a cold snap that goes hand in hand with the blooming of the blackberries and the dogwoods. Always something fun to watch.
On to moisture patterns for May and the first week of the month will continue that trend and the carryover of what I’m expecting in April, one or two events in that first week or so. But storm chasers, after that I’m thinking things will quickly calm down as we get into a dry run with limited thunderstorms. Is it storm free the rest of the month? Of course not, but I don’t think we see the 5 to 6 events we typically see in an average May. I think rainfall will be below average for this May in St. Louis. This would be out of the ordinary, because the month of May is one of the wet months for the St. Louis area. So, I’m going out on a limb. However, it is May an we have to stay up to date with all the outside plans, graduations, weddings. and sporting events. It’s hard to talk about some drought weather in May, but we have to at least think about it
Things to look for in May
Watch for lightning bugs--or fire flys-- on warm evenings.
The chigger season begins and runs through September
Coyote pups begin emerging from their dens
Major points for May 2017
Mild to warm temperatures much of the month...great for all the outside plans.
Active weather pattern for the first week to 10 days of the month then then the storm action really drops off
Hints of drought...very strange for the month of May
The focus during the Spring season will be a very slow start on tap for the month of March then a rocket ship into warmth and thunderstorms in the month of April with growing concerns about an up-tick in severe and tornadic storms. That carries over into May but then a rare flip, going dry and rather quiet for the rest of the month. The controlling global weather feature will be a neutral pattern in Pacific Ocean temperatures but I’m getting some strong signs that an el Niño could be developing and growing late spring and especially into the summer season. But summer is just a distant thought right now and for another long range weather forecast.