1912 Regina Cyclone Disaster Report
Earth 270 – Disasters and Natural Hazards
Professor Stephen G. Evans
April 4th, 2014
Regina was hit by its first ever tornado on June 30, 1912, but it is still the deadliest tornado in terms of human lives lost to have occurred in all of Canada to date. The tornado was estimated to have been an F4 in magnitude, with wind speeds of 333-418 km/h, and struck without warning to many. It spawned 18 km to the south of Regina and cut northward through the city, passing through it in roughly three minutes. In the event, a total of 28 lives were lost, more than 200 were injured, more than 2500 were left ...view middle of the document...
This is because they are flat, low-lying, and devoid of topographically features that block the movement of air masses (Abbott, P. L., 2009). Thunderstorms in these areas can be transformed into twisters when wind-shear conditions are created as these three air masses collide: “(1) A low-altitude, northward flow of marine tropical air from the Gulf of Mexico that is humid and has temperatures at the ground in excess of 24° C; (2) a middle-altitude, cold, dry air mass moving down from Canada or out from the Rocky Mountains at speeds in excess of 80 km/hr; and (3) high-altitude jet-stream winds racing east at speeds in excess of 240 km/hr” (Abbot, P.L., 2009). Air mass (1) is warm and rises to provide a powerful updraft, which is rotated one direction at its middle by the cold air mass (2), and another direction at its top by fast moving air mass (3), creating wind shear and atmospheric instability, which can result in a funnel. The funnel is drawn by the updraft into the thunderstorm which tilts it and lowers the air pressure, which strengthens the updraft and creates updraft flanks. The funnel cloud then increases in rotational velocity as it elongates to make contact with the ground (Abbott, P. L., 2009). It was reported that the afternoon on which the tornado hit was intensely hot and humid, as Regina was experiencing a heat wave (Heidorn, K.C., 2008). This environmental circumstance seems to fulfill the description of (1), but one can only infer that the other necessary conditions must have also been present that day for a tornado, especially one of that strength, to occur.
The Regina tornado in 1912 has been rated at an F4 on the Fujita scale through surveys of the aftermath of the destruction, and analyses of photographs of the damage (Heidorn, K.C., 2008). The Fujita scale was invented in 1971 by Tetsuya “Ted” Fujita, and provides a method of approximating tornado wind speeds through qualitative assessments of damage to buildings and trees by observers (Abbott, P. L., 2009). An F4 tornado on the Fujita scale is one that would result in “well-constructed houses leveled; structures with weak foundations blown off some distance; cars thrown and large missiles generated”, and would correspond to having a wind speed of 333-418 km/h (The Tornado Project Online, 2013). The 1912 Regina tornado easily picked apart houses constructed of wood (Figure 3), and heavily damaged buildings constructed from brick and concrete (Figure 4). It was also reported by witnesses that the tornado was able to lift grain elevators and fling them “like toothpicks”, as seen in Figure 5 (Heidorn, K.C., 2008). The warehouse district was hit particular hard (Figure 6).
The United States is the most tornado-ravaged country in the world by sheer number, getting hit by an estimated 800 tornadoes each year. In comparison, tornadoes are only reported to hit Canada an estimated 80 times each year by Environment Canada, which is still the second...