Peter Yang photographed the funnel cloud from Blockhouse Creek about 3 miles away as I stood directly underneath the cloud base seen at the bottom of the funnel. The cloud base was rotating very slowly and drifted slowly Northeast. Once the funnel became a tornado it reversed it's direction and followed a Southeast track through Mason Creek. I was standing on my front porch when the tornado reached my house. Using the Fujita Scale table below as a guide, it appears that we received F1 level damage while the houses behind ours sustained damage closer to F2 levels.
F-Scale Number | Intensity Phrase | Wind Speed | Type of Damage Done |
---|---|---|---|
F0 | Gale tornado | 40-72 mph | Some damage to chimneys; breaks branches off trees; pushes over shallow-rooted trees; damages sign boards. |
F1 | Moderate tornado | 73-112 mph | The lower limit is the beginning of hurricane wind speed; peels surface off roofs; mobile homes pushed off foundations or overturned; moving autos pushed off the roads; attached garages may be destroyed. |
F2 | Significant tornado | 113-157 mph | Considerable damage. Roofs torn off frame houses; mobile homes demolished; boxcars pushed over; large trees snapped or uprooted; light object missiles generated. |
F3 | Severe tornado | 158-206 mph | Roof and some walls torn off well constructed houses; trains overturned; most trees in forest uprooted |
F4 | Devastating tornado | 207-260 mph | Well-constructed houses leveled; structures with weak foundations blown off some distance; cars thrown and large missiles generated. |
F5 | Incredible tornado | 261-318 mph | Strong frame houses lifted off foundations and carried considerable distances to disintegrate; automobile sized missiles fly through the air in excess of 100 meters; trees debarked; steel re-inforced concrete structures badly damaged. |