March 2023 Overview – Midwestern Regional Climate Center

Temperature

The average March temperature for the Midwest was 35.3°F, which was 1.6°F below the 1991-2020 normal (Figure 1). Average temperatures were slightly above normal in the far eastern region and below normal in the far western region, with near normal conditions in between (Figure 2). Monthly minimum (Figure 3) and maximum (Figure 4) temperatures followed a similar pattern. Statewide average temperatures ranged from slightly above normal in Kentucky and Ohio to 6.5°F below normal in Minnesota (Figure 1). The month began with temperatures 5-13°F above normal across the southeastern half of the region, resulting in over 120 daily high temperature records broken or tied from March 1-7 (Figure 5). On March 1, Evansville, Indiana measured the earliest 80°F day on record, dating back to 1897. After a warm start, a prolonged period of below-normal temperatures settled across the region, slowing plant growth and development that had initiated in late winter and early spring across the lower Midwest.

Precipitation

March precipitation totaled 3.25 inches for the Midwest, which was 0.69 inches above normal, or 127 percent of normal (Figure 1). Across the region, monthly precipitation totals ranged from 1-4 inches across the upper Midwest and 4-12 inches along an axis from southern Missouri to Ohio (Figure 6). Statewide precipitation totals ranged from 0.61 inches below normal in Iowa to 2.19 inches above normal in Indiana. Rankings indicate the 13th wettest on record for Indiana and the 20th wettest for Missouri. In Michigan, Kalamazoo (wettest, 93 years of data), Grand Rapids (2nd wettest, 130 years of data), and Lansing (5th wettest, 157 years of data) all had a record or near-record wet month. Paducah, Kentucky had the 4th wettest March dating back 82 years. A generally active weather pattern brough numerous rounds of heavy precipitation to the Midwest, resulting in over 550 daily high precipitation records (Figure 7 and Figure 8).

Snow

March snowfall was above normal across the upper Midwest, except for south-central Minnesota which was slightly below normal (Figure 9). Snowfall totals from northern Minnesota to northern Michigan ranged from about 10-50 inches, with the highest totals on the southwest shore of Lake Superior (Figure 10). The Rhinelander area in northern Wisconsin measured the snowiest March dating back 99 years. Appleton, Wisconsin had the snowiest March on record (106 years of data) with 29 inches. In Minnesota, Duluth had the 3rd snowiest March and St. Cloud had the 4th snowiest. Snowfall was limited across the lower Midwest, which is typical for March.

Drought

By month’s end, the US Drought Monitor indicated that 84 percent of the region had no dryness or drought (Figure 11). Drought that had been affecting southeast Michigan was nearly gone, and conditions in western Minnesota showed improvement. Iowa continued to be the primary drought-affected area, with about one-third in drought and one-third abnormally dry. Only a very isolated area of southwest Missouri had drought conditions worsen during March.

Severe Weather, Flooding, and Snowfall on March 3

A strong low-pressure system traversed the United States, bringing severe storms to the lower Midwest and winter weather to the north on March 3 (Figure 12). The storm system intensified as it approached the Midwest, which resulted in all-time low atmospheric pressure readings in Louisville, Kentucky and in Evansville and Terre Haute, Indiana. Extremely high winds (40-70 mph) blanketed much of the Midwest, with peak gusts topping out at 79 mph in Louisville. Power outages were widespread across Kentucky, and affected portions of Indiana, Ohio, and Michigan. At least 15 tornadoes were confirmed across the Ohio River Valley. A large swath of 2-5 inches of rain fell along an axis from southeast Missouri to western Ohio. On the north side of the system, 5-10 inches of snow fell across southern Michigan.

March 31 Tornado Outbreak

A strong cold front moved across the Midwest on March 31 igniting a severe weather outbreak from Iowa and Missouri eastward through Ohio (Figure 13). As of this writing, at least 93 tornadoes had been confirmed in the Midwest region by the National Weather Service along with 10 fatalities (Indiana-5, Illinois-4, Ohio-1). The strongest tornado from this event occurred in southeast Iowa and was rated an EF4 with maximum wind speeds of 170 mph. This outbreak produced Indiana’s first tornado-related fatality since March 2, 2012. Hundreds of preliminary hail and high wind reports accompanied this outbreak, resulting in significant and widespread damage to buildings, trees, roadways, and powerlines. On the northern side of this storm system were cooler temperatures and gusty winds that prompted blizzard warnings across southern Minnesota and western Wisconsin. High winds coupled with heavy, wet snow caused downed trees and power lines, and left thousands across Minnesota without power. Portions of northern Wisconsin and Michigan’s Upper Peninsula received upwards of 20 inches of snow.