Meteorologists: Dry, hot summer doesn't necessarily mean warm, dry winter

An ongoing drought and a scorching mid-summer don't necessarily translate into a warm and dry winter, government meteorologists say.

Kevin Deitsch, a meteorologist at the National Weather Service in Des Moines, said colleagues recently researched if a carryover is likely. Despite 75 percent of Iowa experiencing extreme drought conditions, according to the latest U.S. Drought Monitor, Deitsch said the answer is no.

“Just because we have six months of dry conditions doesn't mean the next six will be dry or wet,” he said.

Deitsch predicts precipitation will be near normal and temperatures slightly above normal the next three months statewide. But there are no guarantees.

“Three-month outlooks are very tough to get right. The weather is always changing,” Deitsch said.

Last winter was a perfect example. The National Oceanic and Atmospheric Administration predicted a colder and snowier-than-normal winter in the Northern Plains, much like the previous four.

Instead, Northeast Iowans, depending on a person's perspective, enjoyed or despised a relatively mild winter. Average snowfall statewide, 16.1 inches, was half as much as normal, according to state records. The average temperature for December through February was 28.2 degrees, 6.6 degrees above normal.

NOAA will release its winter outlook on Thursday.

AccuWeather.com, based at State College, Pa., recently released its winter weather forecast. Meteorologist Andy Mussoline said Iowans should expect near-normal temperatures and below-normal precipitation, which includes snow.

“Keeping the drought in perspective, there's nothing in much of relief,” he said.

Mussoline said a weak El Nino - warmer-than-normal water temperatures near the equator in the Pacific Ocean - is likely to affect winter weather. The jet stream tends to push north, bringing warmer temperatures and dry conditions the vast majority of the time.

La Nina typically has the opposite affect. Cooler-than-normal water temperatures can cause the jet stream to dip south, which lets Arctic air from Canada migrate to the Midwest.

Deitsch said neutral conditions exist, which influenced the NWS winter outlook.

The last two winters didn't follow El Nino or La Nina (last year) patterns, said State Climatologist Harry Hillaker.

“There's not a lot of confidence on how things are going to go,” Hillaker added.

That doesn't keep weather prognosticators from trying.

The Old Farmer's Almanac, which boasts an 80 percent accuracy rate, predicts a mild and dry winter in Iowa. However, almanac forecasters say areas suffering from drought will receive enough moisture to bring improvement.

The long-range almanac forecast said the coldest periods in Iowa will be in late December, early January and early to mid-February. The snowiest times will be in mid- to late November, mid- to late December, early January and early March.

Businesses that help people remove snow and stay warm pay attention to long-range forecasts, but prepare for a normal winter regardless.

John Hand II, assistant manager of O'Donnell Ace Hardware in Cedar Falls, said it's better to have enough snowblowers and ice melt available than not enough. The store has left overs from last year.

“We have to proceed as if winter is coming,” Hand said. “We're setting up for it now; you have to be prepared.”