Released: October 10, 2002
’Rainmaker, Go North -- Nebraska Needs Help, Too’
MANHATTAN, Kan. – Climatologists are warning Nebraskans to prepare for months of continued drought, but the long-term outlook for Kansas is almost the exact opposite.
"The current El Niño already is influencing weather across much of Kansas, but El Niños’ impact here tends to be most obvious in December, January and February," said Mary Knapp, State of Kansas climatologist. "So, October-November weather should be close to normal – a real improvement from summer’s drought-prone weather. Then the winter months should be wetter and milder than average."
The only areas with less-than-favorable odds are northwest and perhaps west-central Kansas. Pockets of land there have been registering moisture deficits for up to three years. The upcoming winter could leave them "as high and dry as Nebraska," said Knapp, who maintains the state’s official Weather Data Library, housed with Kansas State University Research and Extension.
The climatologist said early October’s weather was a foretaste of what’s likely to happen.
Knapp’s records run back into the 1800s, but she also gets daily updates from automated weather stations across Kansas. So, she’s able to trace the exact results of each weather system. In one of this month’s early rainfalls, for example:
* Northwest Kansas communities such as St. Francis and Goodland received from 0.17 to 0.5 inch.
* East from there, many sites received 1 inch or more.
* Across the south, everyone got good moisture, with a few stations registering 5 or more inches.
"You could tell how dry our soil still was. Areas with 3 inches of rainfall had little runoff. The soil soaked everything up, leaving little moisture to recharge streams, rivers and lakes," Knapp said.
Climatologists are still learning about El Niño weather systems. Although the 1990s seemed to have El Niños back-to-back, the systems are episodic, she said. Plus, historical records show their impacts can vary widely. Those impacts also can vary from place to place in both timing and intensity, due to such local weather influences as air-routing mountain ranges and the Jet Stream.
"For example, this El Niño system developed much more slowly than many scientists were expecting. It doesn’t seem to be unusually strong now; still, no one can accurately predict more than the general outlook for the next few months. As a result, Kansas could have a few really intense cold snaps, yet have a warmer-than-average winter," Knapp said.
El Niños result when an area of the Pacific Ocean warms up and causes wind shifts. Months later, those shifts affect the weather in both North and South America.
The major impact for Kansas usually is that winter’s weather starts being dominated by low pressure systems tracking from the southwest – often the "Four-Corners" area where Arizona, New Mexico, Utah and Colorado meet.
"These systems tend to contain more moisture than the colder Arctic fronts that blast out of Canada," Knapp said.
This pattern already has started to emerge. Wrapped as all low pressure systems are in counterclockwise air movement, Four-Corners fronts this fall have been reaching out to pick up moisture in the Gulf of Mexico and then pour heavy rains on Texas, Oklahoma, and both southeast and south central Kansas. Colder, drier Arctic systems have been sweeping through northern Nebraska, the Dakotas, Minnesota and Wisconsin.
"This difference in types of fronts is why you sometimes can see a central state with flooding in the south and drought in the northern counties," Knapp said. "It’s also why northeast Kansas can benefit from an El Niño, while the northwest misses out. The southeast corner of Nebraska can benefit, while the rest of that state remains locked in drought."
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1993 Floods ‘Broke’ El Niño Rules
MANHATTAN, Kan. – The Midwest’s 1993 flooding "broke the rules" for El Niño weather. Conditions were wetter to the north than in the south, according to Mary Knapp, head of the Kansas Weather Data Library housed at Kansas State University.
"A clear example of the departure from normal was Missouri, which had historic floods that spring from Kansas City to St. Louis, but extreme drought across the south," she said.
The rule-breaking floods got their start in 1992, Knapp explained. Across the nation’s upper half, summer and winter both were wetter than normal. By the following spring, soils were super-saturated. And a huge snow melt had no place to go except the region’s streams and rivers.
Meanwhile, Mt. Pinatubo – a volcano in the Philippines – erupted again, after erupting even more forcefully in 1991. By the end of 1992, Pinatubo had caused 722 deaths and added to an already record-large ash cloud, which still was affecting Earth’s weather in ‘93.
During the "year of the flood" itself, a strong high pressure system in the Bermudas completed the unusual weather pattern. It blocked every rain-producing front that tried to track across the Midwest’s southern half, Knapp said.
K-State Research and Extension is a short name for the Kansas State University Agricultural Experiment Station and Cooperative Extension Service, a program designed to generate and distribute useful knowledge for the well-being of Kansans. Supported by county, state, federal and private funds, the program has county Extension offices, experiment fields, area Extension offices and regional research centers statewide. Its headquarters is on the K-State campus, Manhattan.
Mary Knapp is at 785-532-6247