Why We'll Never See Another EF5 Tornado

Summary

This video delves into the mysterious EF5 tornado drought, exploring why no tornadoes have been rated EF5 in over a decade. Despite high-end EF4 tornadoes causing catastrophic damage, discrepancies in damage assessments, radar measurements, and subjective rating processes have kept tornadoes from achieving the highest classification. The script examines the evolution of the Fujita scale, the debate over its limitations, and theories about why EF5 ratings might be intentionally withheld, from insurance concerns to institutional biases. Ultimately, the video stresses that while ratings are important, the real focus should be on the devastating human impact of these powerful storms.

Takeaways

• 😀 The last rated EF5 tornado occurred over 11 years ago, marking the longest drought of such tornado ratings.
• 😀 The EF scale, originally developed by Dr. Tetsuya Fujita in the 1970s, classifies tornadoes from F0 to F5 based on damage left behind.
• 😀 The Enhanced Fujita (EF) scale, introduced in 2007, aims to be more accurate by categorizing damage indicators in 28 sub-categories.
• 😀 While mobile Doppler radar offers precise wind speed measurements, tornado ratings are still primarily based on damage surveys, leading to discrepancies.
• 😀 In 2013, the El Reno tornado in Oklahoma had wind speeds measured at 291 mph but was downgraded from an EF5 to EF3 due to a lack of supporting damage.
• 😀 Discrepancies between radar wind speeds and ground surveys led to arguments about whether certain tornadoes should have been rated as EF5.
• 😀 Some tornadoes, such as the Vilonia (2014) and Rolling Fork (2023) tornadoes, came close to the EF5 threshold but were rated as EF4 due to issues with damage indicators.
• 😀 The National Weather Service (NWS) bases ratings on damage assessment rather than direct wind speed measurements, despite the availability of more accurate tools.
• 😀 Some conspiracy theories suggest that the NWS withholds EF5 ratings due to insurance or FEMA concerns, but these have been debunked.
• 😀 The EF5 drought is attributed to several factors, including stricter criteria for EF5 classification, improved construction standards, and better understanding of tornado behavior.
• 😀 New developments in tornado rating systems, including the integration of wind measurements, offer hope for a more accurate system in the future.

Q & A

What is the significance of the EF5 rating in tornado classification?

The EF5 rating is the highest possible rating on the Enhanced Fujita (EF) scale, used to classify tornadoes based on the damage they cause. Tornadoes rated EF5 are extremely rare and signify the most intense and catastrophic tornadoes.

Why has there been a drought of EF5-rated tornadoes in recent years?

The drought of EF5-rated tornadoes is due to a combination of factors, including stricter damage assessment criteria, evolving construction standards, and discrepancies between wind speed measurements from mobile radar and ground damage observations.

How did the Enhanced Fujita (EF) scale evolve from its original version?

The EF scale was originally developed by Dr. Tetsuya Fujita in the 1970s, using a broad six-point classification system. In 2007, the scale was refined to the Enhanced Fujita (EF) scale, introducing 28 damage categories to provide a more detailed and consistent classification.

What were some of the key issues with the original Fujita scale?

The original Fujita scale had broad descriptions for each category, which made it subjective and open to interpretation. This led to inconsistencies in tornado classifications between different surveyors.

How did mobile Doppler radar impact tornado classification?

Mobile Doppler radar provided a more direct and accurate measurement of tornado wind speeds, allowing meteorologists to assess wind speeds more precisely. However, discrepancies between radar measurements and ground damage still exist, complicating tornado classification.

Why was the El Reno tornado in 2013 downgraded from EF5 to EF3 despite its extreme wind speeds?

Despite wind speeds of 291 mph measured by mobile radar, the El Reno tornado was downgraded because the National Weather Service (NWS) policy emphasized ground damage surveys, which did not support an EF5 classification due to insufficient evidence of EF5-level damage.

What role do damage indicators play in the EF rating process?

Damage indicators are used to assess the extent of destruction caused by a tornado. These indicators help determine the EF rating, with higher damage levels corresponding to higher ratings. However, factors such as debris and nearby surviving structures can complicate this process.

What is the controversy surrounding the Vilonia EF4 tornado in 2014?

The Vilonia tornado in 2014 displayed damage consistent with EF5, but was rated EF4. This was due to uncertainties about how much damage was caused directly by the tornado versus flying debris, and concerns about surviving structures, such as trees and poles, which affected the damage indicators.

What are some of the conspiracy theories regarding the withholding of EF5 ratings?

Some conspiracy theories suggest that EF5 ratings are withheld to benefit insurance companies, to minimize payouts, or to avoid triggering FEMA resources. However, these claims have been disproven, as insurance and FEMA relief are not directly tied to tornado ratings.

How do construction standards influence tornado ratings, particularly in Dixie Alley?

In regions like Dixie Alley, where construction standards are often weaker, mobile homes and less sturdy buildings may dominate as damage indicators. This can lead to tornadoes with EF5-capable damage being rated lower, as weaker structures may not withstand even high-end EF4 tornadoes.

What advancements are being made to improve tornado classification in the future?

A new tornado classification scale is in development, which will incorporate both wind measurements and damage indicators into the rating process. This aims to provide a more accurate and comprehensive system for classifying tornado intensity.