ST. LOUIS, MO - 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 are ending, but Spring struggles here in St. Louis. The key to early Spring is swings, swings that give us some hope that Spring is near and swings 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.
There is a lot of chaos for the month of March with a true conflict of interest in the atmospheric patterns. That is never a good sign when trying to put together a long-range forecast. The see-saw pattern of the Winter will continue into at least the beginning of the Spring season. So, March will continue with its well-known split personality with a battle between winter hanging tough and some green shoots of spring. Remember, more times than not winter has the upper hand. The overall pattern will see the continuing fade of la Nina into a neutral ocean pattern in the Pacific Ocean. Let’s think a weak la Nina at best. So where does that lead us? I am thinking it is a slow transition to Spring. On the whole, the month will bring near to slightly above average temperatures and that is chilly to cold. However, I do think we could see a week in the middle of the month that will be rather mild for March in St. Louis. The simple rule of thumb for March is don't rush the spring season. Hold back on spring garden plans and expected limited time to be out and about. The good side of my expected temperature pattern is that it will slow the tree budding and slow but not stop the start of the allergy season. The hardcore, solid cold should stay to our east and northeast but commercial planting will have a slow start.
On to moisture and, yes, there can be snow in March. It is typically one of our bigger months for snow, but the overall pattern of the Winter that brought the expected lack of snow will run into the month of March. In turn, I’m not really excited once again about March snows. I think we will see some snow, especially in the early third of the month, but the large-scale patterns will keep the focus well south or well north keeping us stuck in between and on the dry side. But this will not be a bone-dry month. Let’s expect some snow and some rain, even a few rumbles of thunder and flashes of lightning. I don't see the month bringing much in the way of severe weather but it won’t be storm free. As a result, let’s think moisture will be near to a little bit above average for the month. This should keep the area rivers, large and small, in check so I am not really concerned about March river flooding. However, as we move forward into the spring season the combo of severe weather and flooding will be on the rise.
Things to look for the month of March
- The red maples begin to bloom
- Ticks start to appear and in the middle of March
- Purple Martins arrive
March 2018 Highlights
- All about see-saw temperatures...chilly to cold wins but a week in the middle of the month looks rather mild
- A slight up-tick in moisture...limited snow...moisture near to slightly above average
- Some storms but severe weather tough to find...no flooding concerns
April is one of the great months when it comes to weather in St. Louis. It’s all about variety and variety is king in the month of April as winter really lets go and Spring starts to flex its weather muscles. This variety can create just about anything, snow, rain, wicked thunderstorms, flooding, and always the risk of tornadoes. It’s tough going when it comes to forecasting both short and long range, but that has never stopped me.
The month of April will bring some Spring changes, but Winter does not want to completely let go. So we go kicking and screaming into the month of April. This, like a lot of Aprils in St. Louis, will be an interesting and rather challenging month for forecasting, short and long term. There are not a lot of fast balls, but plenty of sliders and curves. The large-scale pattern is neutral when it comes to the oceans and that’s a problem that results in trouble on the horizon. The flip flop in temperatures will continue becoming more common place with our St. Louis weather. There will be some mild to warm days, especially toward the end of the month but with April struggling so will our temperatures. I am thinking temps will run a little below average for the month. The cooler temperatures will not stop the allergy season. The tree pollens will come alive for the entire month. Saying goodbye to the Winter chill will be a slow process, but Spring will win the battle by the end of the month.
My real interest comes with the rain and storm patterns for this April. This is where the real curve balls come into play and that means my confidence is a little low. Why? That neutral large scale pattern, or lack of direction, means moisture patterns could be all over the place. With that said, battles will be setting up in the atmosphere right in the middle of the nation as warm air from the south battles with the cold air trying to hang tough. I think this April will reverse the drought situation and we get wet with above average rainfall and an above average thunderstorm pattern. With a growing uptick in storms as we go through the month, I think we will see five to six strong to severe weather events all bringing heavy rain, hail, wind, lightning and possible tornadoes. One or two events could really be on the mean side. Higher than average rainfall means the concerns will grow on the area rivers. Rises will happen quickly with flash flooding and flooding comes back into the picture on the large and small river systems. The focus on severe weather will be much like last April, from the St. Louis area and points south into the Tennessee and the lower Mississippi valleys. Let’s stay alert in April.
One other question, could it snow in April? It is not out of the question in the first seven days, but I am not thinking anything big.
Things to look for in April
- The tent caterpillars start to appear
- Hummingbirds start to return
- Robins and other birds start to build their nests
April 2018 Highlights
- A slow swing into spring resulting in below average temperatures until the end of the month
- Five to six strong to severe thunderstorm events
- Expect flash flooding and some fast rises on the large and small river systems
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 months. May has that bad-boy image of being a rock and roll month known for its big-time thunderstorms along with heavy rain, flooding, and our trade-marked severe thunderstorms.
This May will bring a fair share of Springtime weather along with increasing hints of Summer. However, my thoughts on March and April will still be a factor in May. That means a slow squeeze into the Spring and Summer seasons, especially for the start of the month. Overall this May will bring some very pleasant days and nights as we go thru the month. I think when we add up the temperatures, readings will be near to slightly below average. That means the warming of the soil will be on the slow side. The one feature I like to bring up every May is a run of weather known as the "Blackberry Winter,” also known as the “Dogwood Winter.” It is a cold snap that happens around May 9th, 10th, and 11th. This May, I don’t see any reason why we will not have a Blackberry Winter. Why the name? It is typically a cold snap that goes hand in hand with the blooming of the blackberries and the dogwood trees? So yes, some chilly times but also that steady rise in temperatures. This is excellent for the gardens to get growing and the baseball season to come alive.
On to the moisture patterns for the month of May and the uptick in wet weather I’m expecting in April should continue to roll for the entire month of May. I am expecting a little break in the wet weather for the first part of the month, about the same time of the cold snap. But for the middle and end of the month of May, the atmosphere really shows some signs of cooking with a fair share of rain and strong to severe thunderstorms. Typically, we see five to six storm events in May and let’s keep that idea on the table. Like in April, the focus on severe weather will be from the St. Louis area and points south into the lower Mississippi valley. May can be a rather wet month and that's the road I’m going down with rainfall amounts running near to a little bit above average. Keep a close eye on the weather and the short-term forecasts especially with all the weddings, graduations, and all kinds of sporting events. This is all good news after the drought of the Fall and the Winter. But when talking thunderstorms, we have to be concerned with flash flooding and large-scale flooding on the area rivers.
Things to look for in the month of May
- Watch for lightning bugs--or fireflies--on warm evenings
- Chigger season begins and runs through September
- Coyote pups begin emerging from their dens
May 2018 Highlights
- Temperatures will have a steady rise during the month but thinking this May will be on the cool side
- Cool snap around the 9th to 12th...the blackberry winter
- Near to above average storms and plenty of rain. Watch for more flash and large river flooding
Spring 2018 Summary:
The focus during the Spring season will be a very slow start to the season for the months of March, April, and May. Yes, the season will be warming up but it will be a slow process. We’ll see more twist and turns with temperatures and a reverse in the dry, drought pattern. We may need to bring the drought back for the Summer season, but that's for my next long range weather forecast.