The calendar says August, but Wednesday will shout “autumn” in the Wichita area.
Highs will struggle to reach the low 70s as a strong cold front descends from Canada, forecasters say.
“It’s a pretty strong cold front coming down … abnormally strong for this time of year,” said Andy Kleinsasser, a meteorologist with the National Weather Service in Wichita.
Wednesday’s highs will be as much as 20 degrees below normal, Kleinsasser said. Thursday and Friday will see highs in the low to mid-80s – mild for mid-August.
The unusually strong cold front is the latest to dip into the Sunflower State from Canada, reflecting a weather pattern that has persisted for much of the past two months.
The ridge of high pressure that commonly camps out over the southern Great Plains during the summer – leading to long stretches of hot, dry weather because it deflects fronts and moisture – set up elsewhere this year.
“It is weaker and farther west than normal,” said Mike Smith, a senior vice president at AccuWeather.
The strong El Nino weather pattern in place in the equatorial Pacific has been pumping moisture from the coast of Mexico through Oklahoma, Texas and Kansas, where it has been interacting with a steady stream of fronts plunging south.
The result has been substantial flooding in Oklahoma and Texas and almost tropical conditions in Kansas. Parked on the northern edge of the jet stream that has brought persistent thunderstorms to the southern Plains, Wichita recorded its sixth-wettest July in history, with 7.4 inches of rain.
That followed the second-wettest May in Wichita history.
“We started the summer wet, and it just kind of reinforced it this summer,” Kleinsasser said.
There were just three 100-degree days in Wichita in July but 21 days on which at least light rain fell. So far this year, there have been nine days on which at least 1 inch of rain fell and two on which more than 3 inches of rain fell.
“I wouldn’t say this is a bizarre pattern,” said Jaclyn Ritzman, a meteorologist for the Wichita branch of the weather service. “It really depends on where that ridge sets up as to where the storms can go.”
There were 10 days of similarly heavy rains by mid-August two years ago and 13 in 2008, weather service records show.
This time of year, the upper-level jet stream is rather weak, which means any thunderstorms that form won’t move quickly, Kleinsasser said. As a result, rainfall totals can add up quickly.
“It seems like we get a steady train of systems every couple of weeks, which gives us some needed rains,” Kleinsasser said.
So much rain has fallen across the Sunflower State this spring and summer that less than 7 percent of the state is in drought, and the section that is – in northwest Kansas – is only “abnormally dry,” the lowest category on the U.S. Drought Monitor.
In contrast, more than 80 percent of the state was in some stage of drought at the start of 2015. Dodge City has recorded six days of at least an inch of rain so far this year, double the average of the past 10 years and matching the top figures of the past decade.
Even in southwest Kansas, where lawns and crops are usually kept green only through irrigation this time of year, vegetation and field crops are lush as August enters its latter stages.
“It’s a beautiful environment,” said Larry Ruthi, meteorologist-in-charge of the Dodge City branch of the weather service.
Forecast models suggest the “death ridge” will stay where it is through the end of September, Ruthi said, meaning Kansas can expect periodic showers to continue.
“They’ve been very prolific, very efficient rain producers,” Ruthi said of the summer storms.
Ruthi and other meteorologists cautioned that Wednesday’s cool peak temperatures – southeast Kansas may not get out of the 60s – does not mean the Sunflower State is in for unusually harsh weather this winter.
“There’s not a direct correlation” between temperatures in late summer and in winter, Ruthi said.