Content-Length: 12317 | pFad | http://www.spc.noaa.gov/faq/tornado/ef-scale.html
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| FUJITA SCALE | DERIVED EF SCALE | OPERATIONAL EF SCALE | ||||
| F Number | Fastest 1/4-mile (mph) | 3 Second Gust (mph) | EF Number | 3 Second Gust (mph) | EF Number | 3 Second Gust (mph) |
| 0 | 40-72 | 45-78 | 0 | 65-85 | 0 | 65-85 |
| 1 | 73-112 | 79-117 | 1 | 86-109 | 1 | 86-110 |
| 2 | 113-157 | 118-161 | 2 | 110-137 | 2 | 111-135 |
| 3 | 158-207 | 162-209 | 3 | 138-167 | 3 | 136-165 |
| 4 | 208-260 | 210-261 | 4 | 168-199 | 4 | 166-200 |
| 5 | 261-318 | 262-317 | 5 | 200-234 | 5 | Over 200 |
*** IMPORTANT NOTE ABOUT ENHANCED F-SCALE WINDS: The Enhanced F-scale still is a set of wind estimates (not measurements) based on damage. Its uses three-second gusts estimated at the point of damage based on a judgment of 8 levels of damage to the 28 indicators listed below. These estimates vary with height and exposure. Important: The 3-second gust is not the same wind as in standard surface observations. Standard measurements are taken by weather stations in open exposures, using a directly measured, "one-minute mile" speed.
| NUMBER (Details Linked) | DAMAGE INDICATOR | ABBREVIATION |
| 1 | Small barns, farm outbuildings | SBO |
| 2 | One- or two-family residences | FR12 |
| 3 | Single-wide mobile home (MHSW) | MHSW |
| 4 | Double-wide mobile home | MHDW |
| 5 | Apt, condo, townhouse (3 stories or less) | ACT |
| 6 | Motel | M |
| 7 | Masonry apt. or motel | MAM |
| 8 | Small retail bldg. (fast food) | SRB |
| 9 | Small professional (doctor office, branch bank) | SPB |
| 10 | Strip mall | SM |
| 11 | Large shopping mall | LSM |
| 12 | Large, isolated ("big box") retail bldg. | LIRB |
| 13 | Automobile showroom | ASR |
| 14 | Automotive service building | ASB |
| 15 | School - 1-story elementary (interior or exterior halls) | ES |
| 16 | School - jr. or sr. high school | JHSH |
| 17 | Low-rise (1-4 story) bldg. | LRB |
| 18 | Mid-rise (5-20 story) bldg. | MRB |
| 19 | High-rise (over 20 stories) | HRB |
| 20 | Institutional bldg. (hospital, govt. or university) | IB |
| 21 | Metal building system | MBS |
| 22 | Service station canopy | SSC |
| 23 | Warehouse (tilt-up walls or heavy timber) | WHB |
| 24 | Transmission line tower | TLT |
| 25 | Free-standing tower | FST |
| 26 | Free standing pole (light, flag, luminary) | FSP |
| 27 | Tree - hardwood | TH |
| 28 | Tree - softwood | TS |
A 95-page PDF file explaining the development and makeup of the Enhanced F-scale is available here.
Fetched URL: http://www.spc.noaa.gov/faq/tornado/ef-scale.html
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