The new hottest place on Earth: Death Valley, California

As any weather aficionado can avow, Earth's most iconic weather record has long been the legendary all-time hottest temperature of 58°C (136.4°F) measured 90 years ago today at El Azizia, Libya on September 13, 1922. One hundred thirty six degrees! It's difficult to comprehend that heat like that could exist on our planet. For 90 years, no place on Earth has come close to beating the unbelievable 136 degree reading from Al Azizia, and for good reason--the record is simply not believable. But Earth's mightiest weather record has been officially cast down. Today, the official arbiter of Earth's weather records, the World Meteorological Organization (WMO), announced that the all-time heat record held for exactly 90 years by El Azizia in Libya "is invalid because of an error in recording the temperature." The WMO committee found five major problems with the measurement. Most seriously, the temperature was measured in a paved courtyard over a black, asphalt-like material by a new and inexperienced observer, not trained in the use of an unsuitable replacement instrument that could be easily misread. The observer improperly recorded the observation, which was consequently in error by about 7°C (12.6°F.) The new official highest hottest place on the planet is now Death Valley, California. A remarkable high temperature of 56.7°C (134°F) was measured there on 10 July 1913, at Greenland Ranch.


Figure 1. The trading post at Al Azizia, Libya in 1923. The photo was taken from the Italian military fort located on a small hill just south of the trading post. It was at this fort that the temperature of 58°C (136.4°F) was observed on Sept. 13, 1922 (used with permission from the family of Gen. Enrico Pezzi).

The story behind the overturning of Earth's most hallowed weather record
Today's announcement is the culmination of a 3-year research effort begun by wunderground weather historian, Christopher C. Burt. His blog post today, World Heat Record Overturned--A Personal Account, provides a fascinating detective story on how the record came to be cast down--and how the Libyan revolution of 2012 almost prevented this from happening.


Figure 2. The new official hottest place on the planet: Death Valley, California. Wide open spaces, infinite views, intensely salty water, mind-boggling heat. What's not to love about this place? Image credit: Wunderphotographer SonomaCountyRAF.

Dead Heat: The Video
Don't miss the 25-minute wunderground video, Dead Heat, a detective story on how the El Azizia record was overturned.

Atlantic tropical update
Tropical Storm Nadine is recurving to the northwest and north well east of the Lesser Antilles Islands, on a track that would likely keep this storm far out at sea away from any land areas. However, Nadine may eventually threaten the Azores Islands or Newfoundland; the models are divided on how the steering currents will evolve next week, and we cannot be sure which way Nadine will go during the middle of next week.

The models predict that a trough of low pressure off the U.S. East Coast may serve as the focus for development of a non-tropical low pressure system on Sunday or Monday, but this low will likely form too far to the north to become a tropical storm. The GFS model has been predicting a tropical wave coming off the coast of Africa may develop next week, but has not been consistent with the timing or location of the development.

In the Western Pacific, Super Typhoon Sanba is an impressive top-end Category 4 storm with 155 mph winds, and is headed north-northwest towards a possible landfall in Korea early next week.

Given the importance of the new world record all-time high temperature, I'll leave this post up until Saturday afternoon, when I'll post an update on the tropics.

Jeff Masters