Horrendously wet weather in 2019 already has cut deeply into U.S. corn and soybean production either by lost acreage or by very late planting. The potential production shortfall is already a significant number, but a new study by World Weather, Inc. points toward a possibly higher-than-usual potential for early-season frost and freezes this autumn. Such an event could easily put the final nail into the U.S. production coffin.

This year’s unusually wet weather has set many rainfall and flood records across the eastern Great Plains, Midwest, Delta and the southeastern states. It is not unusual to have one or two of these regions wetter than normal during multiple seasons, but it is rare to have three of these areas experiencing similar conditions. This year has been excessively wet in all four regions for a full year, and that has only happened in a handful of years since the late 1800s. That year, by the way, ended in April. The unusually wet weather in the southeastern states came to a roaring halt in May when it quit raining for several weeks and the region became excessively dry. Portions of the Great Plains, Midwest and Delta continued their wetter bias right through the majority of June.

There have been seven years in which all four crop areas noted above were wetter than usual for a full year. When World Weather, Inc. looked at each of those years to see what happened during the following summer there was no clear signal. Half of the summers that followed were still wetter biased and the other half turned drier. Many traders, food companies and farmers have been concerned that — like in 1983 — the nation might turn suddenly hot and dry around the middle part of summer, leading to more production issues. However, that does not seem to fit with all the other weather influences that are present this summer. El Niño favors a little more moisture and less heat as does the solar cycle, although the solar minimum years tend to have a drier bias in August. Those August drier solar minimum years tend to be cooler biased as well, and if this year is influenced by these features, it might be hard to come up with a hot, dry, scenario for July and August.

60-day departure from normal participation in U.S. ended June 24.

Most of the data World Weather, Inc. has perused in recent weeks suggests a gradual drying trend will evolve over the next few weeks and months. July will start out with frequent precipitation, but its intensity will slacken as time moves along. By late July and early August, the precipitation will be much lighter and less frequent and even though temperatures might not be as warm as usual, the Midwest, Plains and Delta will slowly dry down. The primary reason for exception will come from tropical activity that may impact the southern U.S. from time to time late this summer and early autumn.

The summer weather environment should slowly become more favorable for crop development and production potentials even for late planted crops. However, the wet and milder bias to temperatures at times may keep crop development rates behind the usual curve, and with many corn and soybean fields planted later than usual, there is a good chance that crops will be quite immature when September rolls around. That raises the need for an extended growing season this year. Warm weather must last deeply into the early autumn to get crops mature enough to be unaffected when the first frost and freeze arrives.

This year’s rainy weather pattern, even though it has set records, has followed a pattern similar to that of 1965, 1983 and 2001. These are lunar (18-year) cycle years that are closely linked to 2019. All four years have had a similar upper air wind flow pattern that generated months of wetter biased conditions, some flooding, and a few bouts of notably cool weather. Each of the years 1965, 1983 and 2001 suggest that summer weather will continue to be active, but more so in the higher latitudes. In other words, the wetter biased pattern should shift into Canada and the northernmost U.S. as we have already seen in the final two weeks of June.

Early frost potentials

When considering early frost and freeze potentials, we first looked at these three lunar cycle years and found early frost and freezes occurred in both 1965 and 1983 in the north-central United States, but not in 2001. We then expanded our study to include two other well-known years that had delayed crop development. Those years included 1995 and 1974. Both of these latter years had early frost and freezes, and the occurrence was quite similar to those of 1965 and 1983, favoring the area from the central Plains to the Great Lakes region most often.

The year 1995 was like this in which planting was extremely late in the United States. Even though abandonment in 1995 was nowhere near as great as that of this year, there are comparative trends. May 1995 and May 2019 set records for rainfall and the precipitation patterns were quite similar. The year 1974 was late with its crop development, but not because of too much rain. Delays in crop development in 1974 resulted from a very cool growing season. To a certain degree, both 1965 and 1974 seem to have some similar temperature traits, although 1965 was much wetter.

After looking at these years for a while, World Weather, Inc. realized that 1965, 1974, 1995, and to a lesser degree, 1983, were all years that occurred just prior to the solar minimum — similar to this year. After looking deeper into this similarity, we learned that 2001 (another of the lunar cycle years) had a wetter bias but experienced no early frost or freeze. One of the biggest differences between 2001 and these other years is in the fact that the solar minimum was nowhere close by. The common denominator seems to be the solar minimum because there is no other relationship between the three lunar cycle years and the two late crop development years except the fact that the solar minimum was approaching.

Previous studies regarding the solar minimums already had proven a bias toward cooler early autumns and the evidence here seems to be suggesting that the lunar cycle years that occur close to the solar minimums are more likely to have early frost and freeze events in the north-central United States compared to lunar cycle years that occur while the solar minimum is far removed.

Since the lunar cycle is an 18-year cycle and the solar minimum occurs every 10 to 12 years, it becomes mathematically difficult to get these patterns to line up frequently. But they are lined up for 2019, and for that reason World Weather, Inc. believes there is a greater-than-usual potential for early frost and freezes this year. If that occurs, many crops may not be mature enough to handle such an event and additional production cuts may come from that.