At a glance, it might look as if 2018 was a relatively “normal” year for St. Louis in terms of climate data: The average annual temperature was 57.3 degrees, according to the National Weather Service’s local forecast office — just higher than the 57.1-degree average from 1981 through 2010.
But seemingly normal averages can be made up of seesawing extremes that balance out, and that was the case with area weather in 2018, as multiple months saw record or near-record heat, while others saw the same for cold temperatures.
“Temperature-wise, it was very unusual, in terms of it had a lot of ups and downs,” said Jayson Gosselin, a local meteorologist for the NWS, summarizing 2018.
Those extremes were highlighted by St. Louis’ fourth-coldest April ever recorded, immediately followed by the hottest May since official records began in 1874.
“It was almost a we-went-from-winter-to-summer kind of thing,” Gosselin said.
The city also experienced its eighth-warmest June on record, and eventually its sixth-coldest November.
Although those occasional bursts of cold helped dial down the year-end average temperature, 2018 certainly didn’t lack for heat. St. Louis recorded its second-most daily high temperatures that were “at or above” 80 degrees, Gosselin said, with 148 days topping the mark.
And while the area’s 2018 mean temperature just about matched the 30-year average from 1981 to 2010 — the most recent interval that the NWS uses for historic comparisons — it was distinctly warmer than the agency’s older data. From 1951 to 1980, for example, average annual temperatures in St. Louis were nearly two degrees lower, at 55.4 degrees. (More detailed comparisons to past climate trends could not be examined, since data from the National Oceanic and Atmospheric Administration cannot currently be found online because of the ongoing government shutdown.)
Plenty of recent years have seen bigger, and even record-setting, anomalies for warmth.
“The three warmest years (recorded in St. Louis) are all within the last seven,” Gosselin said. 2012 saw a record average of 61.2 degrees, while 2016 (60.4 degrees) and 2017 (60.2 degrees) were the second- and third-hottest years the city’s record books have seen.
A more normal one-year average such as 2018’s does not alter the overall warming trend — one that has been strongly felt worldwide as a result of climate change that is clearly attributed to human activity.
“Weather doesn’t follow a linear progression. Although we’re in a period of warming and increased precipitation, there’s going to be fluctuations from year to year,” said Andrew Hurley, a professor of history at the University of Missouri-St. Louis with a specialty in environmental history. “What we consider to be a cool year in a recent context, it’s still above average in a historic context.”
St. Louis’ 2018 precipitation totals, meanwhile, were “a little wetter than usual,” said Gosselin, with 42.60 inches measured, compared with 40.96 inches on average. But when it did rain, it poured, as the 57 days with at least a quarter inch of precipitation tied for eighth on the city’s list of such occurrences. That is consistent with a broader climate trend of heavy downpours becoming more common nationally, and particularly in regions such as he Midwest.
Gosselin said that overall, wet conditions had prevailed in recent years, and that 2015 ranked as the city’s wettest year on record.
“In general, warmer air can hold more moisture. So, yes, that is not too terribly surprising,” Gosselin said, describing the wet trend of the recent past.
Other types of precipitation extremes were seen elsewhere in the region. Only a couple hours to the west, Columbia saw the driest April on record, and its 11th-driest spring, overall. In that area, Gosselin said precipitation was below normal in May, June and July, so drought conditions “kind of kept building” — something drought-ravaged farmers around the state were painfully aware of last growing season.
The hot, wet conditions that have become more common in the region can present especially steep challenges for cities like St. Louis, Hurley said — where heat is exacerbated by the urban heat island effect, and precipitation challenges are made worse by the amount of impervious surfaces.
“The type of urban life we’ve constructed ... can make changes more dramatic and amplify the effects of warming and moistening,” he said.
10 of St. Louis' most wicked holiday-wrecking weather events
Thanksgiving 1993: Ice storm closes highways, causes deadly accidents
The first ice storm of the winter hit the area late in the day Thanksgiving, coating area roads with freezing rain that lasted well into the night.
The slippery conditions led to scores of accidents on the roads, which left two people dead and injured others.
Road conditions became so treacherous that officials briefly closed Highway 40 (Interstate 64) near Vandeventer Avenue shortly after 7 p.m. after a series of accidents within a few yards of one another on a downhill stretch. The wrecks involved 10 vehicles, but only one person had minor injuries.
The ice also forced officials to close Interstate 70 at two points near Lake St. Louis in St. Charles County for part of the evening.
New Year's Eve 2010: Tornado outbreak kills one, destroys several homes
Shortly before noon on New Year's Eve, 13 tornadoes cut through the region, downing trees, damaging and destroying buildings and homes.
The strongest of the twisters packed winds near 150 mph and was rated an EF-3 by the National Weather Service.
The storm first touched down in far north Jefferson County, touched down again at the county line, skipped northeast along Highway 30 and crossed Highway 141, when the tornado picked up a vehicle driven by a 70-year-old woman and slammed it sideways into a median wall on Highway 141. She died a week later from her injuries.
That storm crossed the Meramec River, crossed I-270, then grew stronger, moving one home almost 50 yards from its foundation, leaving the worst damage in Sunset Hills, where several homes were destroyed. Lewis Place and Robertsville, an unincorporated area of eastern Franklin County, also were hit hard.
Weaker tornadoes also touched down in the north part of St. Louis, going through The Ville and North Riverfront neighborhoods, Ballwin, and Augusta in St. Charles County.
Christmas 1983: Deadly cold spell sets records, leaves trail of broken water pipes
While the average high on Christmas is 39, many St. Louisans know it can get really cold around the holidays.
But Christmas in 1983 went several frigid steps beyond "really cold."
An unwelcome icy surprise greeted last-minute shoppers, starting on Dec. 23. With most secondary streets still snow-packed from a previous storm, a brutal cold front dropped the temperature to 9 below zero and brought wind, leaving the wind chill well below that.
Christmas Eve was no better. Santa brought the area a heaping dose of Arctic chill. The low temperature hit 13 below, which broke a 101-year-old record, and the -41° wind chill marked the third-lowest recorded value in St. Louis history, according to the National Weather Service.
On Christmas, the high reached all of 7 below, still the lowest high temperature recorded on that date.
And if the cold weren't bad enough on its own, at least 10 people died in cold-related fatalities, including three on Christmas.
In St. Louis, a Fire Department spokesman said it had received at least 80 reports of pipe breaks by sunset on Christmas in all parts of the city, and thousands of homes in the region had no heat or electricity.
A water sprinkler sstem bursting at a gym sent 6 inches of water pouring onto Dorsett Road, forcing St. Louis County police to close that road near Interstate 270 for several hours on the day after Christmas.
Thanksgiving 2004: Winter storm kills 1, knocks out power for thousands
A major winter storm that brought rain, snow and high winds blasted through the area the day before Thanskgiving 2004, leaving one area man dead, knocking out power and MetroLink traffic and bringing travel for numerous holiday travelers to a halt.
While as much as 6 inches of snow fell west of the St. Louis area, closing Interstate 70 near Lake Saint Louis, the metro St. Louis area only saw an inch or two of snow after a morning of hard rain. The bad weather delayed flights for hours.
High winds caused plenty of problems, though. An Affton man died when high winds capsized his 18-foot johnboat on the Mississippi River near Alton. And the gusts knocked a tree onto an eastbound MetroLink train and its power line between Belleville Memorial Hospital and the Fairview Heights station. No one was hurt, though the 25-30 passengers were stuck for two hours.
The snow and wind cut power to about 18,000 customers in north and far west St. Louis County, and some in South County.
Christmas Eve 2010: Winter storm gives area a White Christmas
A winter storm that brought two rounds of snow dumped 3 to 6 inches across the St. Louis area, giving St. Louis its first white Christmas in five years.
St. Louis got 3.5 inches, with higher totals in the Metro East. Authorities reported plenty of crashes in the area, though most were minor, such as slide-offs.
Christmas week 2015: Drenching storms close roads, send rivers near record levels
A string of storms dropped between 8 to 11 inches of rain across the St. Louis metro area starting Christmas night through mid-afternoon on Dec. 28.
That sent a massive amount of water into already high channels, with the Mississippi River rising more than 10 feet in two days, climbing several feet above flood stage in downtown St. Louis and water flowing well above the banks of the Missouri and Meramec rivers.
Officials closed Interstate 44 near Highway 141 (above) when floodwaters inundated the roads. In all, flooding forced nearly 300 roads across Missouri to close, with several in the St. Louis area.
At least eight people drowned in Missouri because of floodwater, according to the governor's office.
New Year's Day 1999: Heavy snow, sleet, cold spell leave an unwelcome icy mess
A major winter storm began dropping snow on the area around noon on New Year's Day, with a slightly warmer night bringing freezing rain and sleet that coated trees and bushes and put a crunchy frosting on the ground.
Most spots in the St. Louis area saw more snow the next morning, though southern St. Clair County had four hours of rain.
In all, nearly 8 inches of combined snow and sleet fell at Lambert International Airport, though totals dropped south and east of there. A bitter cold spell followed the storm, leaving the area iced over for much of the next week.
The wintry mess made roads slippery and cut electricity to some residents after branches heavy from ice fell on power lines. But it could have been much worse: Most area forecasters predicted at least a foot of snow for the St. Louis metro area, and snow totals of 12-18 inches were reported as close as 60 miles northwest and north of St. Louis.
New Year's Day 1987: Storm coats roads in ice, drops nearly 2 inches of snow
A storm bringing freezing rain and snow began to cause problems with occasional squalls during the final day of 1986.
Road crews managed to keep up with the weather until about sunset on New Year's Eve, when another burst of wintry mix hit, leaving a major mess. A spokesman for the Automobile Club of Missouri said that by 8 p.m., "nearly the entire area was covered with a sheet of ice."
As temperatures and occasional snow fell overnight, things became worse for anyone trying to get on the roads. In all, 1.7 inches of snow fell on the area, but scores of vehicles slid into ditches off highways or got into accidents.
As for kids, they didn't seem to have too big a problem, taking the chance to build a snow fort (above) on the holiday.
Christmas Eve 2012 & New Year's Day 2013: Two storms drop several inches of snow
On Christmas Eve, a storm dropping almost 6 inches of snow at Lambert Field and twice that in many spots south of St. Louis County, left a wintry landscape (above) but minimal travel problems.
Temperatures warmed in the next few days, quickly melting the snow, but another winter storm targeted the area on New Year's Day.
A narrow band saw almost an inch of sleet in the evening, and most of the problems stayed north of St. Louis. But Lambert Field wound up with almost 5 inches of snow, parts of western St. Louis County had 3 inches and less fell further south.
That's not to say the storm didn't cause any problems. More than 100,000 customers in the Metro East had no digital cable TV or Internet service for about nine hours after the top of the bed of a salt truck dumping salt cut a major fiber optic cable that was about 16 feet off the ground.
Thanksgiving eve 1983: Heavy rain swamps some streets, leaves drivers stranded
After an unseasonably balmy and dry period, a cold front bringing severe storms and heavy rains left an unwelcome mess across the region the day before Thanksgiving.
About an inch of rain fell at Lambert in a nine-hour span ending Wednesday morning, but more dropped in other parts of the area. That sent streaming water over roads, brought traffic to a standstill at times, caused numerous accidents and left flooding in some places that forced road closures.
Florissant police reported some stranded motorists after they flooded their engines by hitting the water too fast. Other cars also stalled at a construction site at Lindbergh Boulevard and Watson Road, which had water 6 inches deep.
South Lindbergh Boulevard just south of Tesson Ferry Road was under 6 inches of water when a storm drain clogged, leaving the road temporarily blocked. The intersection of Hall Street and Riverview Boulevard in St. Louis was impassable from high water.
Winter is coming: One forecast calls for a brutal season in St. Louis, but then again ...
After below-normal snowfall in St. Louis last winter, people looking forward to seeing the area blanketed in white might want to break out their boots.
That's according to one publication that boasts "amazingly accurate long-range forecasts," especially once the calendar flips to 2019. But another prominent publication has a rather different forecast. Click to read more here.
Here comes 'starm mode': St. Louis truisms
One thing about St. Louis, we get all four seasons. Not in equal portions: the nice weather in spring and fall feels all too short, but we get summer heat and winter snow. Read more here.