National Weather Service Weather Forecast Office

As our damp Northern Plains autumn turns to thoughts of an El Nino affected winter, local forecasters’ thoughts also turn to spring and the prospects for flooding.

Fall soil conditions are quite wet. The very brief respite from above average precipitation this summer was not long enough to allow the river system to fully drain the excess moisture, neither in surface storage areas nor in the soil profile.

Over the summer and fall month, the majority of the significant rainfall has occurred on the North Dakota side of the Red River Valley, with relatively small portions of the Minnesota side affected. Ground conditions in the southern counties of eastern North Dakota (Barnes, Cass, Ransom, Sargent and Richland) and parts of west central Minnesota (Wilkin, Clay, Otter Tail and Becker) are very wet. Soils in many parts of these counties are saturated and surface storage areas are full. Runoff rates from rains in the last week of October were extremely high, contributing greatly to the late season flooding that occurred on the Wild Rice at Abercrombie and Red River in Fargo.

According to the USGS office in Bismarck, this is the highest peak on the Red in Fargo so late in the year (see: Red River Flow in Fargo at Highest Level Ever Recorded for November ).

Soil conditions in the middle counties of eastern North Dakota (Nelson, Grand Forks, Griggs, Steele, and Traill) and northwest Minnesota (Norman, Polk) are a bit better off, but still very wet, with little room for additional water in the soils and surface storage areas. Ground conditions in the northern counties (Cavalier, Pembina, and Walsh) and northwest Minnesota (Kittson, Marshall) are even a bit better off due to lesser rains during the late summer and autumn. Despite the wet October, the overall conditions during the summer and early fall of 2009 have been considerably drier than 2008. Yet due to the wet conditions, timing and amounts of the fall rain, topsoil and subsoil conditions are very similar to those found in the fall of 2008.

Last fall the freeze-up took place early and quickly, from November 8th through 10th, 2008. This led to the saturated top soils becoming a “hard, concrete frost”. These conditions prevailed throughout the winter and into the spring of 2009. The freeze-up has not occurred yet this fall, and the forecasts are not suggesting this will happen until after mid-November.

Winter Outlook points to warmer and drier conditions. This winter season looks like it will be a bit different than last year’s. During the summer of 2009, an El Niño developed and has continued throughout the fall. During typical El Niño winters, temperatures for our region are 2 to 4 degrees above normal, and snowfall tends to be 75% to 80% of normal. While there are other large scale climate signals that can decrease the affect of the El Niño, the winter of 2009/2010 is expected to be warmer and drier than last year. Classic El Niño winters feature less frequent arctic air intrusions, and fewer snow storms. Examples of recent El Niño winters include 2006/2007, 2002/2003, 1997/1998, 1994/1995 and 1991/1992. Below is a table with the average snowfall for Fargo and the University of North Dakota/NWS Climate station and El Niño average snowfall.