Minnesota smashes all-time state precipitation record in 2018

Move over Waseca. It appears Harmony, Minn., set a brand new all-time state of Minnesota precipitation record in 2018.

The National Weather Service cooperative weather observer in Harmony recorded an astounding 60.21 inches of precipitation last year.

2018 annual precipitation map, via the National Oceanic and Atmospheric Administration’s Advanced Hydrologic Prediction Service

That 60.21-inch total smashes the previous all-time state record of 56.24 inches set in Waseca in 2016. While the data is still preliminary and will be verified, it’s very likely accurate.

Significant record margin

The 4-inch margin above the previous record is highly significant to Minnesota climate experts.

Minnesota Department of Natural Resources senior climatologist Kenny Blumenfeld shared some observations with me Wednesday on the stunning nature of the record. Here’s an excerpt that speaks to the magnitude of this latest Minnesota record climate event.

Harmony, in far southeastern Minnesota (Fillmore county), has unofficially demolished Minnesota’s all-time precipitation record. I thought it would be a decade or more before we beat the Waseca record from 2016, and a 60-inch total seemed impossible.

Caledonia and Mabel in southeastern Minnesota also surpassed Waseca’s 2016 record precipitation last year. Here’s more context on the numbers from Blumenfeld:

For December, Harmony received 2.94 inches of precipitation, with a daily high of 1.37 inches on 12/2. This brings their annual total to 60.21 inches, surpassing the Waseca record by 3.97 inches. That value is astonishing and the NWS cannot comment on it or verify it until after the shutdown ends.

The next highest value for the year was Caledonia at 57.97 inches. Mabel recorded 55.55 inches. So three of Minnesota’s five largest annual precipitation values on record were observed in 2018.

Harmony had 18 days with at least 1 inch of precipitation in 2018, and 7 days with at least 2 inches of precipitation. The largest daily precipitation total was just 3.86 inches, so this likely record was not anchored by one major event.

Caledonia’s nearly 58-inch precipitation last year soars more than 21-inches above the annual average.

2018 Precipitation graph for Caledonia, Minnesota via NOAA

Here’s my Climate Cast conversation with Blumenfeld on the latest trends Minnesota climate trends.

More like New Orleans 

So how far out of whack is 60 inches of precipitation in Minnesota? Consider this: 60 inches of annual precipitation is close to average for cities near the Gulf of Mexico like New Orleans. (62.45 inches)

U.S. average annual precipitation map, via NOAA and Oregon State University

Sixty inches is higher than the average annual precipitation for Atlanta, Nashville, Raleigh, N.C., and Tampa, Fla.

Fits Minnesota climate trends

One trend that’s clear in the data? Climate change is making Minnesota wetter. This latest record fits the observed trends of heavier rainfall in Minnesota.

Minnesota DNR

Minnesota’s latest all-time climate record is just one of a string of excessive precipitation events. A sharp increase in mega-rainfall events is occurring. The atmospheric physics of climate change in Minnesota is straightforward. A warmer atmosphere holds more water vapor capable of producing these heavier rains.

The other big climate change signal in Minnesota is a strongly measured trend toward warmer winters. Winters in Minnesota have warmed more than 5 degrees on average since 1970. That’s faster than any other season.

So Minnesota’s latest all-time climate record provides yet another strong data point and further confirmation that our climate is changing rapidly.

Expect the unprecedented.