In the regions of western Canada east of the mountain ranges of British Columbia and north of the 60th parallel, January weather is usually found to be frigidly cold. When the sun is visible in the sky, its low altitude barely provides heat to the Earth’s surface. Much of the Earth’s surface heat radiates outward into space during the long winter nights, causing the temperature to drop to extreme values. Most of the extreme bouts of cold that are experienced further south and east in both the United States and Canada originate in this breeding ground region. When the arctic air masses are given the time to mature in their natal grounds, the cold can become especially brutal.
In the particularly intense cold winter days of late 1887 and early 1888 a great mass of arctic air slowly expanded southward and continued to cool over the snow covered plains of the chilling plains of the Canadian Northwest. Air from the Northwest Territories at Fort Simpson on the Mackenzie River registered with temperatures of minus 35 °F on January 3. A nudge from the upper level winds pushed this air southeastward. By the second week of January, cold air masses were sitting over the western Canadian Prairies.
Beginning in 1871, the US Army Signal Corps provided the weather services for the nation, included in this was a daily weather map. Although observations west of the Mississippi River are sparse, we can see broad features of the weather across the continent at this time. Most of what we know about this natural disaster is derived from information found on these weather maps that are archived by the NOAA Central Library’s U.S. Daily Weather Maps Project.
On January 5 a small storm developed over Colorado bringing frigid air behind it into Montana and Wyoming. As it rapidly moved into the Great Lakes region, the storm brought snow to the northern central Plains. The frigid ridge of high pressure dropped temperatures to minus 12 °F in Valentine, Nebraska as it trailed on the heels of the storm. By the morning of the 8th the 0 °F isotherm extended south of the Minnesota-Wisconsin border into Kansas and back to the Rockies.
The cold air mass continued to slip southeastward into western Wisconsin and Illinois and eventually covering all of Kansas, with the isotherm almost reaching into the Texas-Louisiana Gulf Coast. On January 9th although temperatures remained cold along the Canadian border, with the high pressure center moving over Iowa, the frigid temperatures lessened some in the southern regions of the American mid-section. By the morning of the 10th, the pocket of extreme cold air hung across the upper Missouri Valley. Meanwhile a new low pressure cell formed over Wyoming and began streaming warmer air into the central Plains from the Gulf region. Valentine saw a jump of 24 °F and some places saw rises up to 40 °F.
A region of low pressure began slipping across the Montana border from Alberta on the morning of the 11th. Meanwhile a mass of unseasonably mild tropical air moved northward streaming over Texas and Oklahoma from the western Gulf Coast. Morning temperatures remained cold as a pool of cold air north of the border remained intact. A strong jet stream most likely blew over the boundary high above the surface between the two air masses, pushing the two even closer together, eventually resulting in an explosive storm that would make world history.
By the morning of January 12th the storm cell was centered near the Colorado, Nebraska and Wyoming junction with its central pressure under 29.5 inches. The daily weather map’s synopsis for the past 24 hours...