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Heat records all over: The Northern Hemisphere is in hot water

People line up to take a shower on Biarritz’s beach in southwestern France, where the temperature reached 100.4 degrees Fahrenheit on June 30.  (Bob Edme/AP)
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Over the past week, several locations in Europe observed their hottest weather ever recorded. But this extreme heat was not some isolated phenomenon — it was occurring in many locations in the Northern Hemisphere  simultaneously.

In the past week, Alaska, western Canada and the Pacific Northwest all witnessed record-challenging heat while also enduring a brutal onslaught of wildfires. Meanwhile, Greenland is experiencing exceptional surface melting of its ice sheet, also spurred by recent warmth.

As a backdrop for all of the heat over land, the oceans are near or at record warm levels.

Collectively, these records and indicators of abnormally warm conditions are part and parcel of a warming world.

[Northern Hemisphere snow cover is near record lows]

Round-up of heat milestones

By location, here’s a brief rundown of some of the heat records and near records set recently around the Northern Hemisphere …


  • The new all-time high temperature for any location or date in Germany of 104.5 degrees was set July 5  in the city of Kitzingen. This breaks Germany’s previous record of 104.4 degrees set first in 1983 and then tied twice  in 2003.
  • The hottest June temperature ever recorded of 104 degrees occurred in Madrid on June 30.
  • On Tuesday, Geneva soared to 103.5 degrees, its highest temperature ever recorded. That’s the highest temperature ever recorded in all of Switzerland in July, and the second highest temperature ever recorded in the country during any month. Source: Jeff Masters
  • Paris soared to 103.5 degrees on July 1, the second-hottest temperature it has seen on any day since they began weather records (in 1873)
  • The new hottest temperature ever recorded in downtown Frankfurt of 102.2 degrees was set July 5, according to Jeff Masters, director of meteorology at Weather Underground. Masters found that the Frankfurt airport also set a new record for all-time hottest temperature July 5 at 101.8 degrees.
  • Via Jeff Masters: “The temperature in Maastricht, the Netherlands, hit 100.8°F (38.2°C) on July 2, setting an all-time July heat record for the nation.”
  • London Heathrow climbed to 98.1 degrees July 1, the hottest temperature ever recorded during the month of July anywhere in the U.K. The previous record of 97.7 degrees was set  July 19, 2006.

[This is what’s behind Europe’s heatwave]

(Some reporting in this section by CWG’s Angela Fritz)

Alaska, western Canada  and Pacific Northwest

  • On July 6, it was just the fifth time on record, since 1952, that Anchorage, Juneau and Fairbanks were all 81 degrees or warmer, according to climatologist Brian Brettschneider.
  • Via The Weather Network: “There has never been a hotter day in Cranbrook, B.C., than it was on June 28, 2015 — at least not since records were kept. The town made it to 36.8 Celsius [98.2 degrees], a smidgen higher than its old record in 1925, and the hottest day it has ever experienced, in any month, since record-keeping began in 1901 — at a time when Canada had only seven provinces.”
  • Via “Boise, Idaho, tied its all-time record streak of 100-degree-plus highs on July 4, a string of nine straight days.”
  • Via Seattle hit at least 90 for a record-tying five straight days, ending July 5.  It has not had a temperature below normal for 36 days!


After a cool spring, temperatures have shot up over the ice sheet in the last two weeks. The melt extent on the ice sheet’s surface has surged above 50 percent, much greater than the 1981-2010 average (though  a ways off from the record melting (near 100 percent) that occurred in 2012).

The heat around the Northern Hemisphere is connected

The concentrated pockets of much warmer than normal temperature around the Northern Hemisphere is related to the undulations of the meandering jet stream — we see such pockets every summer. The analysis below, from NOAA data, shows that these pockets of warmth (averaged over the period June 28 to July 6) coincide with the areas setting records (described above) .

But for so much exceptional heat to be occurring all at the same time is highly unusual. No doubt the growing El Nino event, which is helping to transfer vast amounts of heat from the ocean into the atmosphere, is playing a role.

[Weather Service joins call for a strong El Nino event]

But greenhouse gas-induced climate warming is almost certainly also at play here, increasing the likelihood and ease at which new heat records are set around the world, compared to earlier times.

Related reading: See Tom Yulsman’s post – As Parts of Three Continents Bake, Greenland Sees Sudden Spike in Surface Melting and Andrew Freedman’s – Greenland’s ice is melting faster this summer under a dome of high pressure