KANSAS CITY, MO. — November’s repetitive rain events in the US central and southern Great Plains, western Midwest and Delta have ended a prolonged period of unusually dry autumn weather.
September and October were anomalously dry, except for where hurricanes Helene, Francine and Milton impacted the nation. Some analysts believed that the unusual weather in the US Plains and western Midwest was a byproduct of the frequent tropical cyclones affecting the Gulf of Mexico and southeastern United States.
However, seasonal cooling across North America may be signaling something bigger — perhaps an end to multi-year drought.
Weather in North America has been anomalously hot and dry since 2020. The pattern was most persistent in the western parts of the continent in 2020, 2021 and 2022, but it began shifting to the east in 2023 and 2024.
These five years of dryness were comparable to the 1930s, 1950s, 1970s and the period from 1998-2002, all of which carried multiple years of dry and warm weather to portions of North America.
The intensity of drought and the impact were different in each multi-year episode, but each group of dry years began their stretch of anomalous weather with the solar minimum followed by a multi-year La Niña that reduced precipitation and allowed temperatures to swing more wildly than in other years. This infamous 22-year solar cycle likely has reached its endpoint.
Late summer and early autumn 2024 weather was quite dry and warm, once again leaving many analysts concerned that more drought years lie ahead.
The tropical cyclones in the Gulf of Mexico, Caribbean Sea and western Atlantic Ocean did have a big role to play on the development of dryness in the United States. But the same pattern occurred in 1952, and until this month, fear was rising that more drought lies ahead. Quite often, though, seasonal cooling in the atmosphere will bring on a fundamental change in weather patterns — usually in October, but sometimes in November as well.
A dramatic turn in weather occurred this month, with waves of drought-busting rain impacting the central and southern US Plains and western Midwest. Portions of the Delta and Tennessee River Basin felt most of this initially; however, Nov. 19-20 brought the season’s first blizzard and significant precipitation event to the eastern Canada Prairies after bringing a significant rain event to the western Corn and Soybean Belt.
Drought is not over, but two weather patterns have been identified that are expected to prevail this winter and spring.
One will bring frequent bouts of rain and snow to the eastern United States. Areas from the southeastern US Plains, and especially the Delta and interior southeastern states, to the eastern Midwest and Atlantic Coast States will experience periods in which large storm systems will generate big rain and snow events during the winter months.
A second weather pattern will bring cold and dry air into the central United States and a part of Canada. The colder air occasionally will reach into the Great Plains, Midwest and eastern states, and the oscillation between these two weather patterns will generate a few periods of impressive rain and snow during the winter. In the meantime, much storminess is expected along the US Pacific Coast.
These weather trends will prevail in the spring, but as the atmosphere warms, the jet stream will lift to the northwest, forcing the wetter weather pattern to shift northwest so that early spring rain will be abundant again in the western Corn Belt and part of the Great Plains.
The pattern likely will shift a little farther to the northwest during late spring and early summer 2025, bringing rain to Canada and the northern US Plains.
All of this will add up to a wetter scenario for North America weather relative to that of recent past years. It may take a while for this pattern to fill in the gaps, but World Weather, Inc. does not believe there is another broad-based drought year in the making for 2025 in North America.
Dryness will evolve in western North America during the summer, but most key grain and oilseed production areas will deal with more frequent and significant rainfall, rather than a threat of dryness.
Stepping back and looking at the past five years and looking ahead, there is a definite break in the trend. This break is associated with the solar maximum, which may have occurred in October. Traditionally, the often dreaded 22-year solar cycle is likely near its end, and this trend change written about here fits well with past 22-year solar cycles that were relentless with their heat and dryness between the solar minimum and solar maximum. We believe this trait will be seen again in 2025.
The failure of another significant La Niña event to develop in 2024 is another symptom that the atmosphere is changing. La Niña events are usually the biggest contributor to droughts in North America and in some other places in the world, especially lasting over multiple years.
The failure of the predicted 2024 La Niña event from developing speaks more volumes into the fact that this extended period of drought years in North America is drawing to a close.
The next time such conditions may come together may be around 2044, when the 22-year solar cycle will return. Regional droughts and bouts of excessive wet weather will still occur in coming years, and there will be enough adversity to threaten agriculture periodically, but on a much smaller scale than seen in the past five years. Abundant rain may eventually be the threat for agriculture, rather than not enough.