Blizzards are storms that contain heavy snowfall, strong winds, and cold temperatures. The combination of these elements creates blinding snow with near zero visibility, deep drifts, and life-threatening wind chill values.
St. Louis County does experience heavy snowfall sometimes augmented in part by lake effect snow.
Blizzards are characterized by strong winds bearing large amounts of snow. They have the ability to completely immobilize large areas and to isolate and kill humans (and animals) in their path. According to the National Weather Service (NWS), although there is no fixed temperature requirement for blizzard conditions, the life-threatening nature of low temperatures in combination with blowing snow and poor visibility increases dramatically when temperatures falls below 20-degrees Fahrenheit. Blizzards typically occur between October and April, however, they occur with the most frequency from early November to the end of March.
Winter Storm History
Based upon the 1975-1991 historical record, Minnesota averages one blizzard per year. The greatest number of blizzards occurred in the month of January, followed by March and November, respectively. St. Louis County, along with all areas of the state, is susceptible to heavy snowstorms. However, the relatively level and tree-barren terrain of western and southern Minnesota makes those regions more susceptible to the high wind speeds which are intrinsic to blizzard conditions than is the case for St. Louis County. Damages from blizzards can range from human and livestock deaths to significant snow removal costs. During the 1975-1991-time period, there were 49 deaths associated with blizzards statewide, or an average of three deaths per year. Deaths attributable to blizzards have dropped in recent years, primarily due to increased weather awareness and warning capabilities.
Observing winter storm watches and warnings and adequate preparation can usually lessen the impact of blizzard events in Minnesota. Technical advances made in transportation, including improved vehicles and better constructed and maintained roads, have also contributed to the decline in deaths related to blizzard events. Historical estimates of dollar losses associated with blizzard events were not available for the purposes of this analysis. However, costs incurred by state and local government for snow removal associated with disaster declaration number 1158 (January 1997) totaled over $27,300,000 dollars. Blizzards rank ninth out of the 10 natural hazards economically impacting Minnesota according to the statewide risk analysis.
Heavy snowstorms combined with low temperatures can be a significant danger to life and property and can lead to significant cost in snow removal for local governments. Stranded drivers can make uninformed decisions, such as leaving the car to walk in conditions that can put them at risk. Because of the blinding potential of heavy snowstorms, drivers are also at risk of collisions with snowplows or other road traffic. Further, drivers and homeowners without emergency plans and kits are vulnerable to the life threatening effects of heavy snow storms such as power outages, cold weather, inability to travel, communicate of obtain goods or reach their destinations. Heavy snow loads can do damage to structures, particularly in areas where there are no building codes or for residents living in manufactured home parks. Further, the frequency of structural fires tends to increase during heavy snow events, primarily due to utility disruptions and resident’s use of alternative heating methods.
Power outages associated with snow and ice storms can impact residences and businesses through the interruption of equipment and may cause loss of heating ability. Other impacts include waterline breaks. This occurs when the pumps turn on and off due to power outages causing surges in water pressure. These surges can cause pipeline breaks through water mains in weak points. Further, power outages can result in sewage spills due to the failure of wastewater collection equipment. The wastewater systems however have power redundancy built in. In 2001, power outages as a result of an ice-storm led to all but two radio stations being down which limited the ability to spread emergency messages to the public.