May 2014: Earth's 2nd Consecutive Warmest Month on Record

May 2014 was Earth's warmest May since records began in 1880, beating the record set in 2010, said NOAA's National Climatic Data Center (NCDC) and NASA. The planet has now had two back-to-back warmest months on record, since NOAA also rated April 2014 as being tied for the warmest April on record. This is the first time Earth has experienced back-to-back warmest months on record since a four-month stretch during March, April, May, and June 2010. Global ocean temperatures during May 2014 were 0.59°C (1.06°F) above the 20th century average; this ties with June 1998, October 2003, and July 2009 for the greatest departure from average of any month in recorded history. Global land temperatures were the 4th warmest on record in May 2014, and the year-to-date January - May period has been the 5th warmest on record for the globe. Global satellite-measured temperatures in May 2014 for the lowest 8 km of the atmosphere were 6th or 3rd warmest in the 36-year record, according to Remote Sensing Systems and the University of Alabama Huntsville (UAH), respectively. Northern Hemisphere snow cover during May was the 6th lowest in the 48-year record.


Figure 1. Departure of temperature from average for May 2014, the warmest May for the globe since record keeping began in 1880. In Europe, Latvia and Norway had their warmest May on record, as did South Korea in Asia. Portions of Central Asia and Australia were also record warm. No record cold was observed. Image credit: National Climatic Data Center (NCDC) .

Notable weather events of May 2014
According to wunderground's weather historian, Christopher C. Burt, in his May 2014 Global Weather Extremes Summary, an amazing heat wave occurred in China, Japan, and the Koreas the last week of May. Beijing saw its warmest May temperature on record with a 41.1°C (106.0°F) reading on May 30th, and all-time national heat records for the month of May were set for South Korea and China. A remarkable heat wave along the Baltic Sea broke the all time May heat record for Estonia (33.1°C/91.6°F at Kunda on May 19th) and at St. Petersburg, Russia with 33.0°C (91.4°F), also on May 19th. Gambia tied its all-time national heat record (for any month) on May 4th when the temperature rose to 45.5°C (113.9°F) at Kaur.


Figure 2. The deadliest weather disaster of 2014 so far has been the tragic landslide in the Argo District of Badakhshan Province, NE Afghanistan on May 2. Death toll estimates vary widely, from 350 - 2,700. According to Dave's Landslide Blog, the landslide came after prolonged heavy rainfall in the region and occurred in the middle of the day on a Friday, when many people are likely to be at home. The slide occurred in two phases, with an initial slide that buried many people. In the aftermath, many people from local villages went to help, only to be buried by the second landslide. Image credit: BBC correspondent Bilal Sarwary.



Three billion-dollar weather disasters in May 2014
Three billion-dollar weather-related disasters hit the Earth during May 2014, according to the May 2014 Catastrophe Report from insurance broker Aon Benfield. The total number of billion-dollar weather disasters through May is ten, which is behind the record-setting pace of 2013, which had thirteen such disasters by the end of May, and ended up with a record 41 such disasters by the end of the year.


Disaster 1. Torrential rains on May 14 - 15 in Serbia and Bosnia-Herzegovina caused extreme flooding that killed at least 80 people and caused $4.5 billion in damage. The heavy rains were caused by Extratropical Storm Yvette, a strong and slow-moving upper-level low pressure that cut off from the jet stream and lingered over the region for two days, pulling up copious amounts of moisture from the Mediterranean Sea. This aerial view of the flooded area near the Bosnian town of Brcko along the river Sava was taken May 18, 2014. (AP Photo/Bosnia Army)


Disaster 2. Flooding rains in China May 24 - 28 killed 37 people and caused $1.2 billion in damage. In this image we see dark clouds gathering in Guangzhou, Guangdong Province of China on May 22, 2014. Image credit: ChinaFotoPress/ChinaFotoPress via Getty Images.


Disaster 3. An outbreak of severe weather hit the Midwest, Rockies, and Northeast U.S. from May 18 - 23, causing $2.5 billion in damage. In this image taken by wunderphotographer Darhawk, we see a supercell thunderstorm near Denver, Colorado on May 22, 2014 that prompted issuance of a tornado warning.

An El Niño Watch continues
May 2014 featured neutral El Niño conditions in the equatorial Eastern Pacific, and sea surface temperatures have been hovering near the threshold for El Niño, +0.5°C from average, from late April through June 23. However, the atmosphere has not been behaving like it should during an El Niño event. The Southern Oscillation Index (SOI)--the difference in surface pressure between Darwin, Australia and the island of Tahiti--tends to drop to negative values during the presence of an El Niño atmosphere, but has been positive over the past 30 days. Heavy thunderstorm activity over Indonesia and near the International Date Line is typically enhanced during an El Niño event, and was near normal at the beginning of June. This activity has picked up over the past week, but must increase substantially before we can say the atmosphere is responding in an El Niño-like fashion. The Madden-Julian Oscillation, a pattern of increased thunderstorm activity near the Equator that moves around the globe in 30 - 60 days, is currently weak and disorganized, and will not be a factor in moving conditions towards El Niño this week. NOAA is continuing its El Niño Watch, giving a 70% chance that an El Niño event will occur by the summer, with an 80% chance by the fall. In a June 20 article at Climate Central, Stephen Baxter, a seasonal forecaster with NOAA's Climate Prediction Center, said: “we’re nicely on track for a weak to moderate, but still potentially impactful” El Niño event in the fall to winter months.

Arctic sea ice falls to 3rd lowest May extent on record
Arctic sea ice extent during May was the 3rd lowest in the 36-year satellite record, according to the National Snow and Ice Data Center (NSIDC).

Most impressive weather videos of May 2014


Video 1. One of the most spectacular weather videos taken in May 2014 was of a Low-Precipitation (LP) supercell thunderstorm on May 18, 2014, between Wright and Newcastle, WY. The best footage begins about 0:50 into the clip. The rotation of the thunderstorm is beautifully captured. LP supercells usually form in dry regions, where there might be just enough moisture to form the storm, but not enough moisture to rain very hard. You can usually find the updraft on the rear flank (back) of the storm. On radar, an LP will not show up as a hook echo because there's not enough precipitation within the storm to provide the reflectivity. These storms might not look that strong, but they can pack a punch. LP supercells often produce tornadoes and large hail.


Video 2. An EF-2 tornado with 120 mph winds hit this camp for oil workers just south of Watford City, North Dakota, on May 27, 2014. The tornado injured nine people and damaged or destroyed 15 trailers. Dan Yorgason, who lives in a neighboring workers camp to the one destroyed, filmed the tornado from inside his truck. "The tornado was coming down the hill along our only escape route. There was nowhere for us to go. It was crazy," he said. The contrast of the brown of the lower part of the funnel with the white portion of the upper funnel is particularly striking 2:00 into the video.


Video 3. A severed bridge floats down the Bosna River in Bosnia and Herzegovina on May 14, 2014. Here is a video of the bridge before it was swept away.

Win $100 in this month's wunderground "Climate Lottery"
Every three months, the Weather Channel's Guy Walton runs a "Climate Lottery" in his wunderground blog where players guess U.S. temperatures for the coming three months. Last season's winner earned a free 10-year wunderground membership. This winner of the new contest will pocket a cool $100. Simply go to Guy's blog and pick three numbers between 1 and 120 (with 1 representing the coldest possible ranking and 120 being the highest possible ranking) for June, July, and August 2014 U.S. temperatures, plus a tie-breaker “Power Ball” or overall ranking number for summer 2014. Post your prediction in the comments section of the blog. Picks must be made by midnight EDT July 5th. The National Climatic Data Center’s ranking numbers for summer 2014 will be posted on or shortly after September 15th, 2014.

I'll have a new post on Wednesday, as the tropics are quiet in the Atlantic, and no development is expected this week.

Jeff Masters