By Tina Kitt

The Wauneta Breeze

This year’s summer weather — cooler and wetter than average — has many scratching their heads and asking “what’s the deal?”

It’s early August and Wauneta still has not hit 100 degrees in 2009, according to official data from the National Weather Service.

The hottest day so far this summer was July 24 when the mercury topped out at 99 degrees. On that day, the high in Imperial was 101 degrees, the only triple-digit high that town has seen this year, according to the NWS.

Similar conditions have dominated statewide, making 2009 one of the “top 10” cool summers on record in Nebraska. For example, Omaha was 4.5 degrees below normal for the month of July, setting a 100-year record, and this weekend Valentine set a record-low for Aug. 1 at 44 degrees, beating the nearly 100-year-old previous record low of 45 degrees set in 1911.

Moisture-wise, southwest Nebraska is above normal while the eastern part of the state is short. On July 30 the seven-month to-date moisture total for Wauneta hit 19.76 inches, exceeding the average annual total rainfall of 19.31 inches — with five months left to go in the year.

For most, this summer’s temperatures and abundant moisture are greeted as a blessing. Irrigators have been able to idle their wells for long stretches of time, cutting down on fuel and electricity costs. Yards and gardens have needed less watering. People have been able to cut back on the use of their air conditioners.

Still, there are drawbacks. For farmers whose corn, soybean and sunflower crops went in late due to wet spring conditions — or even worse, had to be replanted due to hail — they are hoping for heat units to catch up to normal as fall approaches.

So what’s behind this unseasonable summer weather?

According to the pros, warming ocean waters have translated into a cooler than normal summer for the northern Great Plains, Upper Midwest and eastern U.S. — as well as record-breaking drought and heat in the southwestern U.S. and the Pacific Northwest region.

Art Douglas, a climatologist who heads the atmospheric sciences department at Creighton University in Omaha, says that an El Niño that began building in late spring can be associated with this year’s wacky weather as jet stream patterns around the world are affected by this phenomenon. El Niño is the periodic warming of tropical Pacific waters that occurs on average every two to five years and typically lasts about 12 months.

El Niño’s impacts depend on a variety of factors, explained Douglas, such as intensity and extent of ocean warming, and the time of year. Its effects include weaker trade winds, increased rainfall over the central tropical Pacific, and decreased rainfall in Indonesia. These vast rainfall patterns in the tropics are responsible for many of El Niño’s effects on global weather patterns.

In early July, National Oceanic and Atmospheric Administration scientists announced the arrival of 2009’s El Niño and expect it will continue developing during the next several months — with further strengthening possible — and lasting through winter 2009-10.

Hot blast moves in ahead of fall

The dog days of summer may also be the fiercest of 2009. This week a heat dome is building over the central U.S., with the high pressure ridge expected to push triple digit heat our way from the southwest. Wauneta may see 100 degrees this year after all, but this hot spell likely won’t last too long, with summer’s end on the horizon as fall approaches.

According to Nebraska’s State Climatologist Al Dutcher, those living in the Upper Midwest and Great Lakes Region, may see a surprisingly early end to summer. In a report issued in mid-July, Dutcher said that a high pressure trough located over the Hudson Bay could spell disaster for late planted corn and soybean crops growing in states like Michigan, Minnesota, Wisconsin and North Dakota as well as some areas of Illinois, Indiana and Ohio, as a pool of cold air has moved in early and may strengthen leading to an early frost.

Douglas notes that El Niños are often associated with early snowstorms and increased winter precipitation across the plains. As a bonus, this year’s El Niño may help to possibly reverse drought conditions that have been deepening across Texas and California. “The excess warming of the ocean provides more moisture to the atmosphere, making it more unstable,” explained Douglas.