KANSAS CITY, MISSOURI, US — No single country or group of farmers in the world could be more pleased to hear about the demise of La Niña than Argentina. What a horrific three years of weather it has been, especially in 2022-23 with some crop production slashed by nearly half of the norm. Rejoicing will not stop at the border of Brazil either, with some production cuts occurring in various parts of Brazil in both 2020-21 and 2021-22.  Production issues also occurred in North America, although the greatest agricultural losses were in western Canada and in a part of California and the Great Plains.

Australians will not be dancing in their streets because of the dissipated La Niña.  La Niña brings much farming success to eastern parts of the nation and departing La Niña only opens the door for El Niño. Some computer forecast models are pointing toward the return of El Niño later this year and that can only breed the return of drought in eastern parts of Australia. Producers in Indonesia, Malaysia, Philippines and much of southern Asia also will not be celebrating with the North and South Americans. The coming El Niño later in 2023 promises to return dryness to many of these areas and perhaps some full-blown drought issues could evolve in many of the world’s tropical regions by 2024.

The turnover of atmospheric conditions from La Niña to El Niño brings with it some mixed emotions and certainly an opportunity for climate specialists to reload their jargon for another round of damaging weather in much of the world. Indeed, it will be coming, but during the coming months of transition an entirely different set of weather anomalies are likely to evolve.

California’s recent weeks of deluging rain and copious mountain snowfall has been a blessing for the drought-stricken state that suffered huge agricultural losses in 2022 because of limited water availability. Fruit and vegetable sizes shrank throughout the state and the only saving grace was the sudden insurgence of inflation that brought producers and grocery stores a better bottom line, despite smaller crops because each brought in greater revenue.  It was the consumer that lost out in 2022 with smaller crops and higher prices. The winter excesses in California have brought the snowpack to its highest levels since 1983, which has been the long-standing record for greatest snowfall and snow water equivalencies over a single winter season. Those records are about to be broken if they have not already.

  Additional rain and mountain snow into the spring months could lead to a new problem in California … one that will bring excessive water levels to some reservoirs and one that might warrant the opening of flood gates to release some of the pressure high water might put on dams weakened by multiple years of drought.

Flooding also is expected in the Red River Basin of the north in North America this spring. The headwaters of the Red River are in eastern North Dakota and the river flows northward through southern Manitoba to southern parts of Lake Winnipeg. The Red River has a tendency to get too much snow in La Niña winters and this year is fitting that pattern quite well. Snow depths and snow water equivalents in the region are as high as those in previous flood years like 2011, 2009 and 1997. Flooding also occurred on the Red River in 2019 and 2013, but the floods were not nearly as serious as the first three listed here.

Cool temperatures will limit snowmelt in the upper Midwest, northern Plains and southeastern Canada’s Prairies over the balance of this month. A short-term period of warming in early April will bring on a potential bout of snowmelt, but there could be a new shot of cold materializing in the same region for the second half of April, prolonging the snow melt season and possibly raising the potential for a more notable period of warm weather that will melt much of the snow over a few days immediately after the cold period. Many times when strong warming occurs like that it leads to significant precipitation events as well and the combination of notable rain and/or snow and melting snow can be a death sentence to producers from the eastern Dakotas and Minnesota into southern Manitoba in Canada. Not only would there be delays in spring planting, but there might be some abandonment in the wettest areas.

The cold expected in the second half of April also may have a big influence on weather in the US Midwest, Delta, Tennessee River Basin and neighboring areas of the southeastern states. A deep trough of low pressure may settle into eastern North America during that period of time, sending cold air far to the south, possibly raising damage potentials to some of the wheat crop that experienced more accelerated growth recently brought on by unusually warm temperatures.

In the meantime, there is “potential” for drought relief to occur in US hard red winter wheat production areas. There is a tendency for spring seasons that follow multi-year La Niña events in this 22-year solar cycle to experience some timely rainfall and that trend could bring on better conditions this spring for improved wheat development and production potential. However, that possibility is becoming more clouded by the strengthening of the negative phase of Pacific Decadal Oscillation (PDO).

Negative PDO occurs when ocean surface water temperatures are notably cooler than usual off the West Coast of North America.  At the same time there is usually a pooling of warmer-than-usual ocean water in the north-central Pacific Ocean.

Last year’s weather followed very closely to the years of 1956, 2001 and 1976. The parallel was greatest with 1956, but all three of those years lost the multi-year La Niña event either in the fourth quarter or in the first or second quarters of the New Year. During the demise of La Niña there is usually support for a weakening of negative PDO. This year’s data shows a more robust negative PDO with further strengthening possible over the next few weeks and if that happens, more storminess is possible in California and from there to the northern Plains and upper Midwest this spring raising the potential for a more serious flood.

   A stronger negative PDO would also downplay the potential for relief to hard red winter wheat production areas and it could lead to a stronger ridge of high pressure in central North America from late spring into summer. Adding the stronger negative PDO to the rapid transition from a multi-year La Nina to El Nino can make the high pressure ridge strong enough during the late spring and summer to induce a notable decline in precipitation and an expansion of drought.

   The bottom line is that one man’s blessing of a weather change could be a curse to someone else. Just because La Nina has abated does not necessarily mean improving weather worldwide. Just like in any other year changing weather patterns do not always offer a better end result.

Drew Lerner is senior agricultural meteorologist with World Weather, Inc. He may be reached at [email protected]. World Weather, Inc. forecasts and comments pertaining to present, past and future weather conditions included in this report constitute the corporation’s judgment as of the date of this report and are subject to change without notice.