As Jeff Masters mentioned in his recent blog, a temperature of 54.0°C (129.2°F) was observed at Mitribah, Kuwait on July 21st. According to the Kuwait Meteorological Department this was the hottest temperature ever measured in the country (a reading of 54.4°C/129.9°F observed at the same site on July 16, 2010 has been disallowed as a result of a faulty sensor). The 54.0°C reading also is a new record for Asia and ties a similar reading at Death Valley (on June 30, 2013) as the hottest reliably measured temperature on Earth. The key word here is ‘reliably’. Many hotter temperatures have been reported from around the world in years past. However, all of these have credibility issues. In that vein I am going to revisit a blog I first posted on WU in October 2010 listing all the various claims to temperature readings at or above 54°C (129.2°F). In the years since I made that post I’ve learned more about some of these claims and have thus updated my entries and ‘validity’ scores as a result.
A scorching week in Mitribah, Kuwait culminated in a 54.0°C (129.2°F) reading on July 21st (high temp data on the chart is for the previous day). This is arguably, (along with a similar value observed in Death Valley on June 30, 2013) the hottest temperature ever reliably measured on Earth. Table from OGIMET.
There are just a handful of regions in the world that have the potential of recording temperatures of 54°C (129.2°F) or more (excluding heat burst measurements).
1) Death Valley, California and the Colorado Desert in the southern part of the state (where anecdotal temperatures as high as 130°F have been reported and temperatures as hot as 126°F (52.2°C) officially measured (at Thermal on July 28, 1995 and Mecca on June 26, 1990). Also, the Colorado River Valley from the southern tip of Nevada to the Gulf of California can be as hot or even hotter, with a reading of 128°F (53.3°C) measured at Lake Havasu City, Arizona on June 29, 1994 (this reading is now suspect given problems with temperature observations at many sites in Arizona during the late 1980s and early 1990s. See: this report concerning Tucson)).
2) In 2010 I thought that possibly some portions of the western Sahara Desert, specifically the Tidikelt Depression in Algeria, and lowest areas of northern Mali and northeastern Mauritania might be capable of producing temperatures in excess of 54°C. I no longer believe that to be the case. No reliable temperature above 51°C has ever been measured anywhere in North Africa. There are a few weather stations in these areas, such as In Salah, Algeria and Araouane in Mali but they have never seen temperatures above 50°C in their modern history.
3) Areas around the Persian Gulf. The populated areas along and just inland along the shores of the northern Persian Gulf have measured official temperatures as high as 54°C as we have just recently witnessed at Mitribah, Kuwait, and 53.9°C (129.0°F) at Basrah, Iraq today (July 22nd), a new national heat record for Iraq. Unofficial temperatures of 129°F (53.9°C) have been reported from southwestern Iran as well.
4) The region along the lower Indus River of Pakistan centered around Jacobabad. Temperatures as high as 128.3°F (53.5°C) have been measured here (Moen-jo-Daro on May 26, 2010) and 125° is reached almost every year during May in Jacobabad. We can speculate that at some point 129°-130°F may be possible.
5) Other regions of potential extreme heat include the eastern part of the Dasht E Lut Desert in Iran (no records). MODIS satellite measurements have reported extremely hot surface temperatures in the Lut Desert but there are no weather stations in the immediate vicinity (although I hear such are planned). Further down the list are the Dead Sea area of Israel, Palestine, and Jordan (where temperatures up to almost 126°F (52°C) have been measured, and the central-western inland coastal region of Saudi Arabia (around Jeddah) where 126°F (52°C) has also been measured.
Studies by geographer Mark Jefferson (1926) and by Hoffman (1963) conclude that the highest possible surface air temperature on earth (measured by standard modern instruments) would be in the range of 131-133°F (see Weather and Climate Extremes by Dr. Paul F. Krause and Kathleen L. Flood, U.S. Army Corps of Engineers Topographic Engineering Center paper TEC-0099, September 1997. This is an old report and does not take into account AGW. Nevertheless, as of right now, I think this assumption still holds true.
The ‘World Survey of Climatology, Vol. 10: Climates of Africa’ reproduced the above map of possible absolute extreme maximum temperatures back in 1972, but it is based upon the dubious maximums recorded during the colonial era, and, in fact, no temperature above 124°F (51°C) has ever been recorded in North Africa in modern (post-WW II) records.
Compilation of Reports of Temperatures at or Above 54°C
Below is a list of all both 'measured' and 'anecdotal' absolute maximum temperatures on record above 129°F (54°C). The lists are not completely comprehensive so far as many European colonial measurements made in Africa prior to 1950 in places like Tunisia, Algeria, Libya, and Mali. Multiple readings of 54°-55°C were reported in these countries between 1900-1940.
VALIDITY SCORE: I have rated all the below records on a score from 0-10: (0) Zero means completely unreliable to (10), indisputable.
136.4° (58.0°C) Sept. 13, 1922 Al Azizia, Libya
SOURCE: R. Ufficio Centrale di Meteorologia e Geodinamica; Osservazioni dell anno 1922 Rome, Italy
NOTES: See WMO invalidation of this report.
VALIDITY SCORE: 0
134.8° (57.1°C) July 12, 1936 Tindouf, Algeria
SOURCE unknown, perhaps Service Meteorologique, Dakar
NOTES: The hottest temperature measured at Tindouf in modern records is 118° (47.8°C) in July 1998. The older records (1925-1950) as reported in Tables of Temperature, Relative Humidity and Precipitation for the World, British Meteorological Office, 1967 show an absolute maximum of 122°F for Tindouf. An anecdotal reading of 57.1°C was also reported from Ouargla, Algeria on Aug. 27, 1884. It is not climatologically possible this site (or Ouargla) could have recorded such a temperature given its altitude near 2000 feet.
VALIDITY SCORE: 0
134° (56.7°) July 10, 1913 Greenland Ranch, Death Valley, California, USA
SOURCE: Monthly Weather Review, June 1915, U.S. Dept. Of Agriculture.
NOTES: This site reported several other 130°F+ readings during this heat episode (130° on the 12th and 131° on the 13th) but never again after this July of 1913 event. Many in depth articles have been written about the validity of the measurement. See:
Monthly Weather Review June 1915 pp. 278-280
The climate of Death Valley by Steven Roof and Charlie Callagan, Bulletin of the American Meteorological Society, December 2003.
Weatherwise magazine, 134°, by David Ludlum, June 1963 pp. 116-117
Death Valley’s 134°F Record Temperature Study by William T. Reid, August 29, 2013.
This record has been scrutinized perhaps more than any other in the United States. I don't have much more to add to the debate aside from my belief it is most likely not a valid reading when one looks at all the evidence (see Mr. Reid’s in depth discussion noted above. Normally when Death Valley observes its hottest temperatures they occur during region-wide heat waves. On July 10, 1913 the next highest temperatures recorded in southern California (aside from Greenland Ranch) were just 119° at Heber and 118° at Mammoth Tank. Las Vegas was just 112°. I give a 2-point validity to this only because it still deserves a thorough scientific investigation by an official organization in order to put the record to bed once and for all.
The instrument shelter at Greenland Ranch in 1926. (Photo from Bancroft Library Collection, Univ. of California, Berkeley).
The COOP form for Greenland Ranch in August 1924 shows some very suspicious readings with 16 nights above 100° including a 12-day consecutive stretch of such, including two at 110°! The modern (post 1934) record for Death Valley has never had more than 3 consecutive nights above 100° and a hottest night ever in modern records was 107° on July 12, 2012.. P.S. A low temperature of 41.6°C (106.8°F) was measured at Hoseyniyeh, Iran for the night of July 21-22. This is probably the 2nd highest night time temperature ever measured on Earth (if one discounts the erratic measurements from Death Valley in 1924).
VALIDITY SCORE: 2
131° (55.0°C) June (sometime between 1924-1942) Ghadames, Libya
SOURCE: Libyan National Meteorological Centre
NOTES: Errors in keying in data for all of the 50°C+ recordings at Ghadames have been uncovered by the Libyan National Meteorological Center. For instance, a report of 54.2°C in June 1975 was actually 45.2°C and a 54.0°C reading in May 1969 was actually 45.0°C. Data for Ghadames prior to 1955 is considered unreliable because of instrument exposure issues. The highest reliable temperature measured at Ghadames is 48.4°C (119.1°F) in July 1977. Ghadames is not a particularly hot location in spite of what the old colonial temperature data shows. It has a good long record and the hottest modern (post 1960) temperature using good instruments has been, as mentioned above, just 48.4°C.
VALIDITY SCORE: 0
131° (55.0°C) date unknown Ben Gardene, Tunisia
SOURCE: World Survey of Climatology: Vol.10, Climates of Africa, p.42
NOTES: This site is on the Jefara Plain along the Mediterranean Sea as is Al Azizia, Libya and subject to the Ghibili (foehn-like) wind phenomena. However, no modern temperature above 124°F (52°C) has yet be measured here. The older recordings by colonial stations used thermometers and shelters that probably cannot be accepted today. Furthermore, the modern records from this site do not support the possibility of such a high reading. See note below for Kibili.
VALIDITY SCORE: 0
131° (55.0°C) July 7, 1931 Kebili, Tunisia
SOURCE Service Meteorologique, Tunis
NOTES: There is a disconnect between many of the old (pre 1950) French and Italian colonial temperature records from many African weather stations versus the modern records at these same sites. Kebili is one of those. Between 1920-1933 Kebili reported 50-55°C maximum temperatures almost every summer. But since 2000 its absolute maximum has been only 48.5°C (119.3°F). The older recordings by colonial stations involved thermometers and shelters that probably would not be accepted today. Furthermore, the modern records from this site do not support the possibility of such a high reading. A brief period of modern records from 2000-2010 has a 48.5°C (119.3°F) reading on July 26, 2005. But this is a long way from 55°C (131°F) measured during the 1920-1935 period of record. I give the Kebili record a single point only because at least we have a date and source for the reading and so it could be investigated more closely. The WMO currently accepts this reading as the record for the continent of Africa.
VALIDITY SCORE: 1
130° (54.4°) Aug. 17, 1885 Amos (Mammoth Tank), California, USA
SOURCE: Climatology of California, U.S. Dept. Of Agriculture Bulletin L, 1903
NOTES: the Southern Pacific Railroad maintained several weather stations in the Colorado Desert region of southern California during the 19th century as watering stations for trains using their lines. It is likely that the thermometers and shelters and, most importantly, exposure location of these, was not up to official standards. Mammoth Tank, recorded 128°-130°F every summer between 1883 and 1887. After 1887 it would appear that there was some change in the instruments or shelter exposure since no temperature higher than 122° was reported (from 1887-1903). The old sites of Volcano Springs and Salton (now submerged under the waters of the Salton Sea) once reported temperatures of 129° (June 23, 1902) and 128° respectively. Instruments were most likely overexposed.
VALIDITY SCORE: 1
130° (54.4°C) June (sometime between 1931-1940) Araouane, Mali
SOURCE: Service Meteorologique, Dakar
NOTES: Timbuktu has also supposedly recorded 130°F in the past (its modern record is 47.8°C/118°F in May 1958). Once again, there is a disconnect between the colonial era temperature measurements and the modern-era ones (see Kibili, Tunisia note above). There is no weather station in Araouane now, but the hottest modern and reliable temperature in Mali is 48.2°C (118.8°F) at Gao in May 1988. The older recordings by colonial stations involved thermometers and shelters that would not be accepted today.
VALIDITY SCORE: 0
129.2° (54.0°C) June 21, 1942 Tirat Zvi, Israel
SOURCE: Bio-Climatic Atlas of Israel by Dr. D. Ashbel, Central Press, Jerusalem, 1950, p.125
NOTES: The thermograph trace recording this temperature peaked at 53°C (127.4°C) not 54°C (and two other nearby stations supposedly recorded 52°C/126°F). Somebody wrote on it with an arrow pointing at the peak, '54°'. They misread the thermograph as anyone can see on close examination. However, the Israeli Meteorological Service claims that a standard thermometer was also in the temperature screen along with the thermograph and that it registered 54°C. The problem is the data sheet for this site rounded all its high/low daily temperatures off to the nearest full 1°C. Therefore, theoretically, the high temperature could have ranged anywhere between 53.6°C to 54.4°C. Since we will never know just exactly what the temperature was that day it is difficult to accept the 54°C on face value. The IMS apparently made an investigation of the figure on its anniversary in June 2012. They concluded that the measurement of 54°C was valid but refused to make the details of their investigation public. On those grounds it is not possible for any climatologically minded person to accept the figure. Temperature records expert and climatologist Maximilliano Herrera concludes that the highest reliably measured temperature in Israeli during the heat wave of June 1942 was 51.2°C (124.2°F) at Qalya on June 22, 1942 (and that this is the true record high for Israel).
The thermograph trace recording the June 21, 1942 temperature at Tirat Zvi, Israel, shows that the temperature peaked at 53°C (127.4°C) not 54°C. But somebody wrote on it (with an arrow pointing at the peak, '54°'. They misread the thermograph as anyone can see on close examination. Image credit: Bio-Climatic Atlas of Israel by Dr. D. Ashbel, Central Press, Jerusalem, 1950, p.125.
VALIDITY SCORE: 2
129° (53.9°C) July 7, 2007, July 20, 2005, July 18, 1998, and 129.2°F (54.0°C) on June 30, 2013 Furnace Creek, Death Valley, California, USA and also at Greenland Ranch, Death Valley on July 20, 1960
SOURCE: United States Weather Bureau (USWB), National Weather Service (NWS)
NOTES: These readings were the highest reliably (and undisputed) temperatures yet recorded in the world until the Mitribah reading on July 21st. The measurements were made under standard conditions using modern shelters and instruments. Of interest is that on June 30, 2013 the thermometer actually peaked at 129.2°F (54.0°C) as photographic evidence showed. This reading, therefore, ties the recent 54.0°C measured at Mitribah, Kuwait as the highest reliably measured air temperature on Earth.
To quote Jeff Master’s recent post: A photograph of the official Furnace Creek, Death Valley maximum recording thermometer at time of observation on Monday morning July 1, 2013 (which was for the maximum temperature measured on June 30). The photo shows a maximum of 129.2°F was reached, tying it with the 129.2°F reading at Mitribah, Kuwait, on July 21, 2016, for the highest reliably measured temperature on Earth, according to wunderground's weather historian Christopher C. Burt. Observations at the site are made only at 4 p.m. and 7 a.m. daily. The shelter door is not opened at any other time in order to not affect the ambient air temperature inside the shelter. You may have seen a different image of this same thermometer on the NWS-Las Vegas web site posted July 1, 2013 that shows the temperature just shy of 129°. That is because THAT photograph was taken after the thermometer had been removed from its shelter and turned vertically, which caused the mercury to slip down the tube about 0.3°F. This photograph was taken prior to the thermometer being removed from the shelter. Photo courtesy of Death Valley National Park and NWS-Las Vegas.
VALIDITY SCORE: 10
Anecdotal Temperature Reports
188° (86.7°C) June or July, 1967 Abadan, Iran (heat burst)
SOURCE: News clip, no further info available.
NOTES: This obviously is an apocryphal record. The highest official temperature during the months of June or July 1967 at Abadan was 48.9°C (120°F) on July 15. Not an unusual temperature for this area at this time of the year. Let’s think a moment just what kind of thermometer could have registered 188°F. An oven thermometer?
VALIDITY SCORE: 0
158° (70.0°C) July 6, 1949 near Lisbon, Portugal (heat burst)
SOURCE: News clip, no further info available.
NOTES: The news reports of this event at the time claim this reading was made in the sun not shade. So it cannot be considered a reliable figure. Well something amazing happened here this day but, again, just what kind of thermometer registers up to 158°F?
VALIDITY SCORE: 0
152° (66.7°C) July 10, 1977 Antalya, Turkey (heat burst)
SOURCE: News clip, no further info available.
NOTES: The official maximum temperature at Antalya on July 10, 1977 was 43°C/109.4°F (and for that month 44°C/111.2°F on July 16). There is no reliable record concerning this 152° figure. No evidence physical or otherwise about this event.
VALIDITY SCORE: 0
140° (60.0°C) June 15, 1960 Kopperl, Texas, USA (heat burst)
SOURCE: Tornadoes, Dark Days, Anomalous Precipitation and Related Weather Phenomena, William Corliss, Catalog of Geophysical Anomalies, 1983. See Extreme Weather; A Guide and Record Book, by Christopher C. Burt, and Freaks of the Storm, by Randy Cerveny, for more information on this event.
NOTES: A thermometer outside Kopperl's Bait and Tackle Shop reportedly measured this temperature around midnight following the collapse of nearby thunderstorms. The reliability of the thermometer in question is not known however very few common thermometers are capable of registering a temperature of 140°F. Physical evidence (burnt crops) indicates an amazing heat burst occurred here, but the only thermometer to register it is in question.
VALIDITY SCORE: 1
140° (60.0°C) August, 1953 Delta, Baja, Mexico
SOURCE: Weather and Climate Extremes, Krause and Flood, US Army Corps of Engineers Technical paper TEC-0099, 1997
NOTES: The thermometer used for this reading was considered badly overexposed and this record is invalid. We know it was a hot day and this region could perhaps record some incredible temperature. But 140°F?
VALIDITY SCORE: 0
140° (60.0°C) date unknown Rito, Sonora, Mexico
SOURCE: Weather and Climate Extremes, Krause and Flood, US Army Corps of Engineers Technical paper TEC-0099, 1997
NOTES: The thermometer used for this reading was considered badly overexposed and this record is invalid. We know it was a hot day and this region could perhaps record some incredible temperature. But 140°F?
VALIDITY SCORE: 0
136.4° (58.0°C) Aug. 11, 1933 San Luis, Baja, Mexico
SOURCE: World Almanac 1980
NOTES: The thermometer used for this reading was considered badly overexposed and this record is invalid.
VALIDITY SCORE: 0
136° (57.8°C) July 11, 1909 Cherokee, Oklahoma, USA
SOURCE: Monthly Weather Review, USWB, July 1909 p. 337
NOTES: No information is known about the thermometer used for this reading and the temperature is therefore dismissed in the Monthly Weather Review mention of the event. Physical evidence (burnt crops) indicates something amazing happened here that night, but the thermometer validity is a big question mark
VALIDITY SCORE: 0
135° (57.2°C) July, 1989 Al-Amarha, Iraq
SOURCE: News clip (undetermined)
NOTES: The official maximum temperature measured at Al-Amarha for the month of July 1989 is only 49°C (120.2°F) on July 24. The 135°F reading is obviously a press exaggeration or was made in the sun. No evidence whatsoever to support this
VALIDITY SCORE: 0
133° (56.1°C) June 17, 1859 Santa Barbara, California, USA
SOURCE: The Coast Pilot of California, 1859
NOTES: There is no record of who made this measurement or exactly where it was made in Santa Barbara. Some later sources say it was made on a U.S. coastal geo-survey vessel. IF that is the case then the temperature is not possible since the waters off Santa Barbara in June are never warmer than about 70°F and any wind blowing over the ocean would have its temperature modified by the cool water no matter how hot the air. This report is singular and there is physical evidence (burnt crops and dead animals) that something amazing happened here this day, but the temperature record is impossible to validate.
VALIDITY SCORE: 0
131° (55.0°C) Jan. 21, 1845 Interior of New South Wales, Australia
SOURCE: Monthly Weather Review, USWB, May 1930 p. 208
NOTES: This temperature is mentioned in passing as part of a discussion concerning hottest recorded temperatures from around the world. There is no further information known. Old record and impossible to validate.
VALIDITY SCORE: 0
Conclusions Concerning Anecdotal Temperature Reports
All of the above observations have never been corroborated by any official meteorological organization and are (for the most part) the result of unofficial estimates or measurements made during heat bursts. They are all unreliable for one reason or another and cannot be accepted as valid measurements.
Conclusions Concerning Measured Record Temperature Reports
It would appear Death Valley, California and Mitribah, Kuwait jointly hold the best authenticated value of 54.0°C (129.2°F) as the hottest reliably measured temperatures on Earth. I think it also worth emphasizing the problems of the disconnect between old and modern temperature data from Africa (and elsewhere around the world). There can only be two explanations for this;
1) The climate has become much cooler over the past 50 years in northern Africa, or,
2) The instruments and their shelters/locations during the first half of the 20th century were not as accurate as those used during the last half of the century. At least now we have the ability to double check suspicious data since it comes to us in real-time. Unfortunately, the old errors are harder to fix.
BTW, I will post a follow up to this blog in August with a list of just what are the hottest reliably measured temperatures on Earth now that I've covered which records are not credible.
Christopher C. Burt
Weather Historian
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