Long-term weather prediction? Plan for another wet spring.

posted on Tuesday, February 4, 2020 in Current News

Wet fields this spring

From Michigan Farm News: Jeff Andresen, MSU Extension Agricultural Meteorologist

With an upper air troughing pattern across western North America and ridging across the east, an active storm track set up through the Great Lakes region during much of the first half of January. One storm moving through the region from the10th-12th brought very heavy rain and some snow to much of Michigan, with more than 2.00” observed across almost all of the southern half of the Lower Peninsula (for some climatic perspective, total normal precipitation for the entire month of January is generally from 1.50-2.00”).

It was the most widespread heavy rain observed in Michigan since the February 19-21, 2018 heavy rain/flood event. The precipitation brought soils back to saturation and led to localized flooding in some areas.

For the mid-December through mid-January reporting period, precipitation totals ranged from just under 2.00” across western sections of Upper Michigan to more than 5.00” across south central sections of Lower Michigan (which was in many locations more than 200% of normal).

Milder than normal temperatures were the rule for most of the past few weeks, with reporting period means ranging from 5º above normal across northern sections of the state to more than 9º above normal across far southern sections.

With the main storm track moving through the region during most of the winter, seasonal snowfall totals have varied greatly from north to south across the state, with totals as of mid-January ranging from less than 10” inches (less than 50% of normal) across far southern sections of the state to more than 100” across lake effect snowbelt sections of Upper and northern Lower Michigan.

One additional update on the very wet conditions observed in 2019. Based on data through the end of the calendar year, total precipitation averaged across the state was 41.55”, which is 10.42” above normal and the new all-time wettest year on record in Michigan (since 1895).

Latest medium range forecast guidance suggests some changes in upper air flow across North America in the next few weeks, with the gradual development of more northwesterly flow across the Upper Midwest and Great Lakes region. This would lead to a transition from the recent milder than normal weather to more wintry conditions with normal to below normal mean temperatures.

The new NOAA Climate Prediction Center long-lead outlook for February calls for below normal mean temperatures state- and region-wide. There is no forecast direction on precipitation totals, with near equal chances for below-, near-, and above-normal totals (my own personal opinion leans more towards below normal totals).

The outlook for the February through April period is a bit different and calls for normal to below normal mean temperatures with increased odds of above normal precipitation. As noted in earlier columns, the forecast trend towards wetter than normal weather continues on through the upcoming spring and into the middle of the growing season.