Spring has been a wild ride…of course… that is typical for St. Louis…at times cold, at times hot…very hot…temperatures could not make up their mind.. As expected, April was a rock and roll thunderstorm month…the main features… large and damaging hail and a rather large number of small (EF2 or less) tornadoes…some of the largest hail we have seen in years and a large number of tornadoes.
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The keys to the Summer season...will be this large ocean pattern flip…but changes in ocean temperatures are slow to take place…waters warms slower than land…but the change from El Nino to Neutral to La Nina is right on track… remember the El Nino from the Winter was more of a headfake El Nino and it would not be hanging around…El Nino is dead.
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Most think the Summer Forecast is easy and you are right compared to the other seasons…but not so fast my friend…this Summer looks interesting…and not a slam dunk…that is because there will be part of the nation…in fact a large part, that will have a beast of Summer…others will not…that is tough contrast.
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So this Summer season...ocean temps are all showing their hands...one feature I’m also interested in...is warmer than average ocean temps along the East Coast and the Gulf of Mexico...a factor especially in the hurricane forecast...Also the warmer Pacific temperatures will be a major factor for the Pacific season. I will cover that at the end of this forecast.
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Summer officially begins…June 20th at 3:50 PM.
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Let’s get to work...here we go:
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There are about 20 factors that I look at and study when putting these long range forecasts together… And in my book they all have some heavy weight in the final forecast...and this is just not a quick look...this is a process that goes on every day(yes even in retirement)...I don’t miss the T.V. side at all...but weather is my life… I love it..
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On to the factors that are in play… Here’s a short list...can’t give all my trade secrets away.
The analogs...looking back at past weather and then moving forward to compare what's going on in our atmosphere now… The analogs may be the most important thing in my long range forecast…focusing on 1995, 1998, 2010 and 2016…well that is also interesting.
The solar cycle… we are now in a strong solar cycle…the sun is more active…in fact it is very active…New research by a leading group of solar physicists predicts maximum sunspot activity in late 2024 into 2025.
World wide volcanoes… Not just the activity but the locations...critical in a long range forecast...we have seen an uptick in the volcanic action around the world.
The ocean patterns...just not the Pacific but all around the world.
Over the last 2 decades there appears to be more and more of a correlation between the solar cycle and a El Nino or La Nina. What does all this mean for us…it means we sit back and watch the development… never lump these things into a generic pattern…there are no two solar cycles and no two El Nino or La Nina that are exactly the same… I never try to lump possible weather into one pile…just can’t do that…you should not do that either
There are a number of other features that I look at when it comes to the atmosphere and the oceans...without getting into too much detail...here are some of the items...the most important first...then, in my mind the least important for this Summer season.
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The most important:
The MJO... While the MJO is a lesser-known phenomenon, it can have dramatic impacts in the mid-latitudes. Several times a year the MJO is a strong contributor to various extreme events in the United States.
The eastern pacific oscillation (EPO)
The Arctic oscillation (AO)
The shift to all La Nina.
A warm (PDO) pacific decadal oscillation…maybe more of a feature for Winter than Summer…but it is in place.
A positive (AMO) Atlantic multidecadal oscillation.
The jet stream settles into its typical quiet Summer flow...along the U.S. Canadian border.
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Least important… But important:
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Tropical North Atlantic (TNA)
Indian Ocean Dipole (IOD)
Pacific North American (PNA)
Western and Eastern Pacific Oscillation (WPO)(EPO)
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These are many of the factors that come into play and must be looked at all the time for these seasonal forecasts… So let's get to the details… The Summer season in STL.
JUNE:
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June Facts:
June 1st…sunrise: 5:38…sunset: 8:20
June 30th...sunrise: 5:40…sunset: 8:29
Average high and low: 85.9/67.2…Records: 108(2012)/43(1969)
Average rainfall: 4.49”
Average snowfall: 0.0”
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June Dates:
The Full Moon…June 21–the strawberry moon
Father’s Day…June 16
Summer Begins…June 20
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The major factors:
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*** We will be on the edge of a hot pattern over the southwest and Texas and over the upper Midwest and the Great Lakes…yes that is more than weird for June.
*** June will see more wild swings from pleasant to just plain hot…it’s the building heat from the southwest that will bring our strong heat and the northwest flow will try to keep things in check…the Yo-Yo weather is alive and well.
*** No clear pattern has emerged…as for timing of hot and pleasant…but the swings will be in control
*** Temperatures…we will have some very hot runs of weather but that will get slapped back by runs of pleasant temperatures…so when we add up the numbers…temperatures will average out near average. But there will be times… we will think the beast of Summer is upon us. Make sure the A.C. units are in tip top shape.
*** June is also a month when thunderstorms typically really rock and roll...typically is the key word...in my book it is the wettest month of the year...mainly due to thunderstorms
*** June storms will be active...but nothing crazy active…even with temperature flips…let’s think 2 to 3 strong to severe weather events…nothing like April and early May.
*** All-day rains never happen in June.
*** I think rainfall for the month will be a little below average…but since Spring was so wet…drought is not coming into the picture this June.
*** After some minor to moderate flooding on the big rivers this Spring…flooding in June will stay in check...however when the thunderstorms roll in…each will create a flash flooding set up…small streams and creeks… up and down very quickly…we have had some great examples of this during the Spring.
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Things to look for in June:
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***watch for birds carrying food to their young.
***check evergreens for bagworms
***the cattail blooms are covered with pollen
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JULY:
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July Facts:
July 1st…sunrise: 5:40…sunset: 8:29
July 31st...sunrise: 6:02…sunset: 8:13
Average high and low: 89.6/71.1…Records: 115(1954)/51(19601972)
Average rainfall: 3.93”
Average snowfall: 0.0”
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July Dates:
The Full Moon…July 21–the Buck moon
Independence Day…July 4
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The major factors:
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*** Typically a hot and humid month...we all know that...hard core Summer in STL...but this July should bring a wide variety in our temperatures.
*** It will be a battle between intense surges from the southwest…a hot…at times very hot and bone dry flow and the Summer break from the northwest flow
*** The key…the southwest flow…this allows our temperatures to sky rocket…and even though July records are intense…this bone dry flow could bring a high record or two.
*** The northwest flow will knock back the heat…but it is Summer northwest flow…however any break we get will be welcomed..
*** With the swings…thinking about half the days wicked hot and half the day bearable for Summer…don’t ask which days…an impossible question in the long range.
*** The hot and dry times will have a great effect on the overall temperatures for the month…and I don’t think the northwest flow will do a big job in neutralizing that heat…so temperatures will be above average for this July…but not way above average.
*** This will be close to being the hottest month of Summer…close.
*** With the bone dry southwest flow…humidity levels will not be extreme…not our typical Summer wet washcloth feel. And that is the key to my rainfall outlook.
*** With the swings in temperature you might think the month would be really active…not going down that road because there will be limited moisture coming up from the Gulf of Mexico.
*** Yes, there will be some thunderstorms but thinking frequency will be below average.
*** In turn…thinking that Juy rainfall and storms will be below average. The drought word will start to come into play…the main reason…the dry southwest flow will quickly dry out the soil…and stress plants…farmers and gardeners be alert.
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Things to look for in July:
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***the song bird songs have now subsided...the birds are busy raising their young
***long-tailed weasels breed through August
***watch for hummingbirds bringing their young to feeders.
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AUGUST:
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August Facts:
August 1st…sunrise: 6:33…sunset: 7:54
August 31st...sunrise: 6:48…sunset: 7:23
Average high and low: 88.3/69.3…Records: 110(1934)/47(1986)
Average rainfall: 3.50”
Average snowfall: 0.0”
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August Dates::
The Full Moon…August 19–the sturgeon moon
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The major factors:
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*** We will have plenty of hot weather in July…but thinking once again this August will be the hottest month of our Summer…this is becoming a trend.
*** August could be a pounder of Summer heat.
*** The hot and bone dry southwest flow will be the main feature…a few days of the northwest flow…but the southwest flow is the winner.
*** The dry heat will allow nightime temperatures to relax…not like the heat and humidity that keeps nighttime temps up. So that is a good thing.
*** Records are a real tough thing to hit in the Summertime...because the records are very intense...but this hot and dry southwest flow could snap 2 maybe 3 record high temps.
*** Temperatures when we add up all the numbers will be above average…could be well above average
*** Rainfall...August is typically a very dry month...and this is looking like a very, very dry month…the same reason…the hot and dry southwest flow. Drought will be in the picture.
*** The storm track remains active…but should stay well to our north…and the northwest flow will be weak at best…so rain and thunderstorms will be limited…maybe very limited.
*** So drought is a big concern…so we turn attention to the hurricane season(see that forecast below). Sometimes a Gulf storm could be a drought buster…and the season will get going early…so we will keep an eye on that.
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Things to look for in August:
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***look for large flocks of purple martins gathering for fall migration…also hummingbirds start to head south too.
***late summer molt produces drab colors in robins and other birds...they are not sick
***wild cherries and wild grapes begin to ripen
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TROPICAL-HURRICANE IDEAS:
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In the Summer forecast, I also like to look at the Hurricane season in the Atlantic and Gulf of Mexico…it is looking like the hurricane season from “hell”…how is that for an opening line! This is showing signs of the worst hurricane season in many, many years.
This is all about the neutral pattern in the Pacific jumping full steam ahead into the La Nina pattern…and thinking the season gets off to an early start…in June
Let's review…
El Nino conditions typically knock down the number of storms. El Nino creates more shear…tropical storms and hurricanes don’t like that.
La Nina creates more hurricanes due to weaker vertical wind shear and trade winds and less atmospheric stability. In the Pacific…fewer hurricanes due to stronger vertical wind shear.
Other things: Solar cycles and volcanism play a role in the activity level of hurricanes as they influence the atmospheric and oceanic temperature profiles…and as we all know, the sun is cooking right now.
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So thinking this hurricane season will rock and roll and expecting very high levels of hurricane action… all areas in the Atlantic Basin will be in play with the peak area being the Caribbean, Florida and over the entire Gulf of Mexico. But the east coast and even New England are also very much in play.
Also thinking could easily go through the alphabet in the naming of storms. And the number of hurricanes could easily be over 12. That would be a big-time season.
Enjoy the Summer season...we all know Summer will fly by...before we know it summer vacations are over, the pools close and it is back to school...STL has a lot to offer...get out there and enjoy...but be safe and smart.
My Fall forecast will be out in late August… Time now for any questions or comments...would love to hear from you.