search-rescue.net - Weather/SkyWarn

DHS is mandating that by 30 Sept 2006, all individuals who interact with any government agency or organizations that interact with a government agency and receive federal funding (including federal, state, territorial, local, tribal, private, and NGOs) must have two federal certifications or lose federal funding.

This includes volunteers and spotters, and affects EMAs, ESDAs, Red Cross most but NWS and anyone else as well. A list of all individuals involved with respective entities must be maintained with their certifications,
which DHS will check (probably a 10% spot check or something similar).

This must be done before any transaction occurs, in the case of spotting, making a report. I leave the implications for you all.

The following are what is required:
* "ICS-100 Introduction to ICS"
* "IS-700 NIMS: An Introduction"

ATLANTA --The government is changing how it categorizes tornadoes after finding that it doesn't take 300 mph winds to disintegrate homes and turn cars into missiles -- a 200 mph twister can do just as much damage.

The National Weather Service said Thursday it had changed the Fujita Scale, a three-decade- old system of ranking a tornado's strength, to align wind speeds more closely with actual damage.

"It was apparent that many of the speeds used in the estimates were too large, said Joe Schaefer, director of the service's Storm Prediction Center. "The scale guiding wind speeds wasn't in tune with reality."

The change was introduced at the American Meteorological Society meeting in Atlanta. However, the new system will not fully go into effect until February 2007, giving weather scientists time to adjust to it.

Under the old system, created in 1971, an F-5 tornado -- considered the most powerful of tornadoes -- was capable of destroying a typical frame house, with wind speeds estimated at 261 mph to 318 mph. Since then, engineering studies have shown that much slower winds could cause the same damage.

"It doesn't take 300 mph winds to totally destroy an ordinary frame house," said Greg Forbes, a former member of Penn State's meteorology department who studied tornadoes under Theodore Fujita, the University of Chicago professor who created the scale. Forbes now works for The Weather Channel.

Under the new system, an F-5 tornado -- which can disintegrate a strong frame house after lifting it off its foundation or badly damage reinforced concrete buildings -- has wind speeds of at least 200 mph.

Because the new system still uses actual tornado damage to estimate wind speeds, officials said it is not likely that the new system's lower wind speed rating for the F-5 tornado will result in more tornadoes being classified with the nation's top tornado rating.

The old system rated tornadoes only based on damage to homes. The new system classifies tornadoes based on damage to 28 other types of structures, including trees, mobile homes and other types of buildings.

"If a tornado went over a row of trees and didn't hit a house, there was no way to estimate the scale," Schaefer said.

NOAA NATIONAL WEATHER SERVICE’S IMPROVED

TORNADO RATING SYSTEM NOW OPERATIONAL

NOAA’s National Weather Service fully implemented the Enhanced Fujita (EF) on Thursday , February 1, 2007, to rate tornadoes, replacing the original Fujita Scale. The EF scale will continue to rate tornadoes on a scale from zero to five, but ranges in wind speed will be more accurate with the improved rating scale.

"The EF scale provides more detailed guidelines that will allow the National Weather Service to more accurately rate tornadoes that strike the ,” said Brig. Gen. David L. Johnson, U.S. Air Force (Ret.), director of NOAA’s National Weather Service. “The EF scale still estimates wind speeds but more precisely takes into account the materials affected and the construction of the structures damaged by the tornado."

The Fujita scale was developed in 1971 by T. Theodore Fujita, Ph.D., to rate tornadoes and estimate associated wind speed based on the damage they cause. The EF scale refines and improves the original scale. It was developed by the Texas Tech University Wind Science and Engineering Research Center , along with a forum of wind engineers, universities, private companies, government organizations, private sector meteorologists, and NOAA meteorologists from across the country.

Limitations of the original Fujita scale may have led to inconsistent ratings, including possible overestimates of associated wind speeds. The EF scale incorporates more damage indicators and degrees of damage than the original Fujita scale, allowing more detailed analysis and better correlation between damage and wind speed. The original Fujita scale historical data base will not change. An F5 tornado rated years ago is still an F5, but the wind speed associated with the tornado may have been somewhat less than previously estimated. A correlation between the original Fujita scale and the EF scale has been developed. This makes it possible to express ratings in terms of one scale to the other, preserving the historical database.

The Texas Tech University Wind Science and Engineering (WISE) Center, along with a forum of nationally renowned meteorologists and wind engineers from across the country, developed the EF Scale. The forum began their work in March of 2001 and included participants from several government organizations, universities, and private companies.

The EF Scale will still rate tornado categories from zero to five, but the ranges of wind speed in each category are now more accurate. The EF Scale takes into account more variables than the original F Scale did when assigning a wind speed rating to a tornado. The EF Scale incorporates 28 damage indicators (DIs) such as building type, structures, and trees. For each damage indicator, there are 8 degrees of damage (DOD) ranging from the beginning of visible damage to complete destruction of the damage indicator. The original F Scale did not take these details into account.

Original F Scale		Enhanced F Scale
Rating	3 second gust (mph)	Rating	3 second gust speed (mph)
F0	45-78	EF0	65-85
F1	79-117	EF1	86-110
F2	118-161	EF2	111-135
F3	162-209	EF3	136-165
F4	210-261	EF4	166-200
F5	262-317	EF5	>200