Ag Weather Forum

La Nina to Keep WCB Dry

Bryce Anderson
By  Bryce Anderson , DTN Senior Ag Meteorologist
Connect with Bryce:
Precipitation in the first quarter of 2021 shows above-normal totals for the eastern Midwest, but mainly below normal in the western Midwest and Plains. (DTN graphic)

The Pacific Ocean cool-water La Nina event continues to grab the ag weather news headlines in mid-November. An updated La Nina Advisory from the NOAA Climate Prediction Center (CPC) has some thought-provoking details about the 2020 La Nina event.

The central and eastern equatorial Pacific Ocean has an average temperature of 1.3 degrees Celsius (2.3 degrees Fahrenheit) below normal. The CPC calls this La Nina event the eight-strongest dating back to 1950. Climate forecast agencies now call for a 95% chance of La Nina continuing through the upcoming winter into the spring of 2021; in addition, there is almost a two-thirds probability -- 65% -- of La Nina lasting through the 2021 spring.

During a conference call Nov. 19, Iowa State Climatologist Justin Glisan said that the likely presence of La Nina brings a wide variance in the weather pattern forecast indications across the central U.S. with what Glisan called a "classic" La Nina effect.

That effect includes above-normal precipitation during the rest of calendar year 2020 and the first quarter of 2021 over the northwestern U.S. and in the eastern Midwest. In the western Midwest and all but the northern one-third of the Plains, the forecast has below-normal precipitation. That drier trend in the western Midwest and most of the Plains means that drought areas have a high probability of continuing on that track through spring.

There is also the question of how much the dry fall pattern will affect the 2021 row crop season. The potential is worth thinking about. "The drier-than-normal conditions mean you don't have a lot to work with (on soil moisture)," said Glisan. "This dryness impact could feed on itself."

USDA Midwest Climate Hub Director Dennis Todey noted that severity of dryness is important. "Moderate dryness is not a huge issue," Todey said. "But we see that Northwest Iowa has only 2 to 3 inches of moisture in the 5-foot profile compared with 10 to 12 inches of moisture for a full profile. That is a big decline on supply."

**

Editor's Note: Be among the first to hear Bryce Anderson's 2021 weather outlook, and its implications on crop yields and markets, by attending this year's DTN Ag Summit, Dec. 7-9. Our premier farmer and rancher event is virtual this year, and features thought-provoking presentations on global trade, grain and livestock market outlooks, a look at how farmers are using data to increase profits and build resilience into their operations, the latest on tax issues and many other topics. Speakers include U.S. Ambassador Kip Tom, farmers Reid and Heather Thompson and farm blogger Meredith Bernard, Microsoft Chief Scientist Ranveer Chandra, personal development speakers David Horsager and Jon Gordon, and many more.

You can take part in it all from the comfort of your office or tractor cab. Register at www.dtn.com/agsummit

Bryce Anderson can be reached at bryce.anderson@dtn.com

Follow him on Twitter @BAndersonDTN

Comments

To comment, please Log In or Join our Community .