The development of an upper air trough across central and eastern North America during the last week of October led to northwesterly flow across the Great Lakes region and to an extended period of early winter weather through much of the first half of November.
Mean temperatures for the mid-October through mid-November reporting period were well below normal statewide, generally ranging from 3-6ºF below the long term normals. The upper air pattern also led to an active storm track through the region, with measurable precipitation on more than half of the days in the 30-day reporting period in most sections of the state.
Precipitation totals generally ranged from just under 2.00 across southeastern sections of the Lower Peninsula to more than 4.00” across western and northern sections of Lower Michigan and much of eastern Upper Michigan.
Given the colder than normal temperatures, a significant portion of the precipitation fell in the form of snow. Seasonal snowfall totals of more than 20” were reported by mid-November across some western section of Upper Michigan with snow depths exceeding one foot.
Overall, the cold, wet weather conditions were unfavorable for most outdoor fieldwork activities and slowed grain dry-down rates of unharvested corn. Harvest progress of both corn and soybean crops remains well behind average due to wetter than normal weather during much of the fall season.
Forecast guidance for the next few weeks suggests some de-amplification of the jet stream pattern across North America, which should result in some moderation of temperatures back to at least near normal levels. However, there are a greater than normal number of potential forecast directions from the guidance which collectively lead to lower than normal confidence in the outlooks.
The NOAA Climate Prediction Center outlook for the 3-month December through February period calls for warmer than normal mean temperatures and for below normal precipitation totals statewide, which is consistent with the expected development of El Nino conditions in the equatorial Pacific.
Andresen is a professor of Meteorology/Climatology with Michigan State University’s Dept. of Geography, Environment, and Spatial Sciences; MSUE specialist and the state climatologist for Michigan.