Iowa has had some brutal cold weather in recent weeks--it's been on-again, off-again. Now in early January, the cold weather is about to get as severe as the region has seen in the last 20 years, says the National Weather Service.
Wind chills reached lower than 20 degrees below zero the night of January 2, 2014. Temperatures in Iowa climbed higher on January 3, into the teens and 20s. But that brief respite will end when a cold front moves in January 4, says Kevin Skow, a meteorologist with the National Weather Service office in Des Moines.
Temperatures (not wind chills) will drop to below zero Sunday, and probably won't rise back above zero until sometime Tuesday, he says. On Monday, expected high temperature for central Iowa is minus 5 degrees. The area hasn't had that cold of a high temperature since Feb. 3, 1996. In northern Iowa temperatures could drop to minus 30. Wind chills could be minus 60.
What kind of weather will we have the rest of this winter? Likely colder than normal, says Elwynn Taylor
"We've had several polar outbreaks already this winter and another one is occurring now, in the first several days of 2014," notes Elwynn Taylor, Iowa State University Extension climatologist. He says we may have several more of these polar outbreaks this winter, as he views current weather indicators.~~~PAGE_BREAK_HERE~~~
The cold climate pattern appears to be holding steady over Iowa and other northern states for at least the first couple weeks of January, getting 2014 off to a cold start. Snowfall and precipitation remain relatively uncertain, as climate forecasts continue to project equal chances of dry or wet conditions in the coming month for most of the state.
A year ago, the discussion was about drought. Dryness lingered from summer of 2012, through fall and into the start of 2013. As we enter January 2014, how much of Iowa is still in drought?
Much of Iowa's subsoil moisture supply has been recharged, as we begin 2014
"It's hard to find spots in Iowa that are really dry, but they do still exist," says Taylor. "I've been looking at soil moisture measurements we have around the state. We don't have a lot of our new weather stations established yet, the ones that measure soil moisture in real time. But about two-thirds of the places where we do have measurements are showing soil moisture reserves that are nearly up to normal. They're close to where they normally are for the amount of moisture in the top 5 feet of soil for this time of year."
That leaves about one third of the places ISU is measuring in Iowa that have soil moisture reserves either normal or above. "The current soil moisture situation relieves some of the drought concern as we look toward the spring of 2014," says Taylor.
A year ago reserve moisture supply in top 5 feet of soil was quite dry in Iowa
A year ago, it was a different story. After the 2012 summer drought, Iowa had a dry fall and winter. Farmers last winter were greatly concerned about lack of moisture in the subsoil heading into spring 2013. "However, spring came and we ended up with too much rain and flooded fields delaying planting significantly," recalls Taylor. "Some fields never did get planted in 2013."
He adds, "The way soil moisture has been recharged coming into 2014, I don't think Iowa farmers will have to be concerned about subsoil moisture reserves as we enter spring 2014."~~~PAGE_BREAK_HERE~~~
The exception may be in southeast Iowa, where farmers are frustrated because they didn't get much rainfall in 2013. They received less than most of the rest of the state. "We do have soil moisture measurements in three places now in southeast Iowa," says Taylor. "All three of those weather stations are showing there isn't much moisture in the top 5 ft. of soil profile at the beginning of 2014."
In the dry areas of southeast Iowa, once you get below 18 inches deep, the soil moisture supply is short. In some places you go about one foot down or maybe 18 inches into the soil and you find soil moisture, but there's not much moisture below that depth. Moisture hasn't moved down to fill the entire 5 feet of soil profile yet, says Taylor. He also notes that the top foot or two is a little dry in places in Iowa that haven't had recent rain or melting snow soaking in, as the ground is now frozen.
Early indicators to watch, for clues to 2014 planting and growing season weather
Are there any key indicators we can start watching now, to get a hint as to what weather conditions we may see when we get closer to spring? Or is it too early to tell?
"We're a little bit early," says Taylor. "Of course, the more reliable indicators we've had historically have been the El Nino and La Nina weather cycles, and currently we remain in neutral territory for those. Scientists who work with the data and keep track of El Nino and La Nina are telling us "Don't expect it to still be neutral when we get to March and April. They don't expect 2014 to be a neutral year for this weather indicator."~~~PAGE_BREAK_HERE~~~
So, will we have El Nino or La Nina in 2014? "The weather experts say yes, we'll have one or the other," says Taylor, with a chuckle. El Nino is when surface water temperature is warmer than normal along the equator in the Pacific Ocean. In La Nina years the water temperature is cooler and the weather is more erratic. El Nino years produce better growing season weather for Iowa and the Midwest. La Nina years usually produce problems.
In years when El Nino occurs, growing season weather is more favorable for crops; in La Nina years it's not
The Southern Oscillation Index is an indicator climatologists keep an eye on for clues. The 90 day SOI is now at .31, which is more like La Nina than El Nino. "The SOI is still hanging toward the La Nina side of neutral and acting like it wants to be back in the La Nina phase," says Taylor.
Taylor studies the cycles. "We've had a lot of years where El Nino was the dominant cycle and it is the friend of the Midwest farmer," says Taylor. "Thus, we had years with high corn yields--runs of years of above trend-line yield. We had six years in a row dominated by an El Nino weather pattern, and good yields."
"Most recently we had three years of La Nina," he adds. "La Nina not only caused us problems in the past few years, it also may be indicating perhaps we are switching back to a long-term of being predominantly La Nina." There may be events of El Nino in the middle, but predominantly we could be on a La Nina trend for weather patterns in the next decade or so, says Taylor.~~~PAGE_BREAK_HERE~~~
"That's what we had back in the 1930s, the 1950s and into the 1960s decade," says Taylor. "We don't really relish that because it's a bigger challenge to have good yields and a profitable farming operation in years of La Nina weather patterns. "And when La Nina becomes dominant, it stays around for maybe 20 years and is a main factor limiting yields."
Arkansas weather in March and April indicates what's likely to happen in Iowa in May and early June
For clues to what kind of weather Iowa will have at planting time, Taylor watches what's happening in Arkansas--about a month or so earlier than planting time in Iowa. When does he start watching weather in Arkansas?
"The Arkansas weather becomes a concern, only as we start getting toward April in Iowa," says Taylor. "But I start watching in late February. As the warmer air starts moving north, I watch to see what's going to happen. Often by March, Arkansas has been either wet or dry. Normally it's one or the other. That gives us an indication of the pattern that will be migrating north as the days get longer. Arkansas weather in late March and April is a forecast for what we can likely expect to occur in Iowa and eastern Nebraska in May and early June."
Nationwide, as we begin 2014, the drought has improved compared to a year ago, but drought still persists in the West--especially in California. Showing nearly a 30% improvement in nationwide drought compared to Jan. 1, 2013, the first U.S. Drought Monitor map for 2014, released Jan. 2, 2014, indicates that the West is not out of the woods yet. Drought persisting in California is sparking fear among some weather watchers that 2014 will bring yet another drought year to a significant portion of the country.
The U.S. Drought Monitor is updated weekly and can be found here.