September 2012 Global Weather Extremes Summary
September featured two major Category 5 Super Typhoons in the West Pacific, a tremendous extra-tropical storm in the United Kingdom and some horrific wild fires in Spain. A new national all-time heat record may have been set in Venezuela and some record rainfalls in Pakistan led to floods that drowned hundreds.
Below is a summary some of the month’s highlights.
The month began with an unseasonably strong low-pressure system (970 mb) in the Gulf of Alaska bringing damaging winds to the Anchorage area. Wind gusts of 88 mph (142 km/h) were measured at McHugh Creek in the Turnagain Arm area and 63 mph at Anchorage Airport. Some 55,000 homes lost power during the storm.
The month was generally a quiet one in the lower 48 states. Two weak tornados moved across sections of Queens in New York City on September 8th damaging a yacht club and several residences.
One of the two tornados that traversed a portion of Queens, New York on September 8th. It was originally a waterspout that came ashore at Breezy Point just west of Rockaway Beach. Photo from CNN.
The drought situation across the country stabilized with about 65% of the country under drought conditions with 10% (in the Plains and Midwest) suffering exceptional drought conditions.
It was the coolest September on record for San Francisco with an average temperature of just 58.1°F/14.5°C (previous record was 58.3°F/14.6°C in 1962). This was about 4°F below normal (September is usually the city’s warmest month of the year). The month, however, was warmer than normal in southern California and Death Valley reported its warmest September on record with a 96.3°F (35.7°C) average (previous record was 95.7°F/35.4°C in 1915). On September 8th and 9th the temperature peaked at 119°F (48.3°C), the warmest temperature recorded anywhere in the world during the past month.
The coldest temperature in the northern hemisphere for the month was -44.3°C (-47.7°F) at Summit GEO AWS, Greenland on September 30th. In spite of this cold reading, the Arctic ice sheet was reduced to its smallest size on record (since 1975) by the middle of the month.
SOUTH AMERICA and CENTRAL AMERICA
An intense cold front swept across Brazil, Paraguay, Argentina, and Uruguay on September 15-17 producing violent and destructive thunderstorms. Hail up to 3” in diameter was reported with some of the storms in Brazil with wind gusts to 172 km/hr (107 mph). At least five deaths were attributed to the storms. Prior to the front’s passage record heat gripped the region. All-time maximum temperatures were set at San Matias, Bolivia hit 42.3°C (108.1°F); Corumba, Brazil 42.2°C (108.0°F); and Poxoreu, Brazil 40.5°C (104.9°F). Villamontes, Bolivia recorded 43.1°C (109.6°F) on September 14th (the hottest temperature measured in the southern hemisphere during the month). Amazingly, snow was observed following the cold front’s passage in the southern Brazilian state of Santa Catarina where temperatures fell to -5.6°C on the Planalto Serrano around 1800 m (6000’) elevation.
Venezuela recorded its hottest national temperature on record on September 29th when a reading of 41.4°C (106.5°F) was measured at Coro. The previous national record was 41.0°C at Maracaibo in August 1991.
A very powerful extra-tropical storm impacted the British Isles September 23-26. The highest wind gust reported was 72 mph (116 km/h) at Inverbervie, Scotland on the 25th and the greatest 24-hour rainfall reported was 97.8 mm (3.85”) at Ravensworth, North Yorkshire) on September 24-25. The high winds caused considerable tree and roof damage in Scotland, especially in the Aberdeen area.
Sea foam inundates coastal Aberdeen in Scotland during the ferocious storm of September 23-25 that saw winds gust to 70 mph (110 km/h) in the city. Image from a video still, BBC News.
The temperature extremes for the U.K. during September ranged from a high of 29.3°C (84.7°F) at Writtle, Essex on the 9th to -4.1°C (24.6°F) at Braemar, Scotland on the 23rd.
In France, the weather extremes of the summer (cold and wet in June to mid-July followed by record-breaking heat and drought in August) have decimated the nation’s grape crops and caused wine production to fall to its lowest level in 40 years. Especially hard hit has been the Champagne region. Expect an expensive New Year’s celebration this year.
Wild fires in Spain have burned 1600 square kilometers (615 sq. miles) so far this year with some of the worst fires occurring this past September that was also the driest September on record for the country. About 25 lives have so far been lost.
A deadly flash flood ripped through Adamawa State in northeastern Nigeria on September 15th drowning at least 70. The flood was blamed on heavy rains that forced the breaching of a dam on the Benue River in neighboring Cameroon.
The most powerful typhoon in two years, Super Typhoon Sanba formed in the Western Pacific in mid-September. The storm’s central pressure bottomed out at 900 mb (26.58”) on September 15th and its winds peaked at 175 mph (282 km/h) sustained with gusts to 200 mph (322 km/h). The storm struck Okinawa with wind gusts measured to 155 mph (250 km/h). Fortunately, Sanba weakened prior to making landfall in South Korea where two deaths were reported.
A huge wave smashes into a sea wall in Yeosu City, South Korea as Sanba made landfall nearby on September 17th. Photo from AFP.
Just a week later Super Typhoon Jelawat formed with sustained winds peaking at 155 mph (250 km/h). Okinawa was again directly struck y the storm with wind gusts to 132 mph (212 km/h) reported. The storm eventually passed over Japan’s Honshu Island but only as a strong tropical storm. Tokyo reported wind gusts as high as 70 mph (110 km/h).
The monsoon season, which finally kicked in over portions of India and Pakistan during September bringing, for the most part, beneficial, rains to the region. Jacobabad, Pakistan had only measured 3.2 mm (0.13”) for all of July and August but on September 13-14th a record deluge of 448 mm (17.64”) fell on the city. Of this, 304 mm (11.97”) fell in just 24 hours, an all-time record for the site. Floods in Pakistan claimed at least 450 lives during the month. Flash floods also affected Sikkim in northeastern India resulting in the deaths of at least 30 in the province.
It was a warm month for the country with the national average maximum temperatures being the 3rd highest for a September in the past 63 years. Precipitation was above normal in the north and below normal in the south.
Maximum temperature deciles for Australia during September (top). It was the 3rd warmest for such in 63 years. Precipitation deciles cane seen on the map above. Maps courtesy of the Australian Bureau of Meteorology.
The warmest temperature for the month was 41.9°C (107.4°F) at Curtin Aero, Western Australia on September 23rd and the coldest -9.0°C (15.8°F) at Cooma, New South Wales on September on September 2nd. The greatest calendar rainfall was 97.0 mm (3.82”) at Thredbo Village, New South Wales on Sept. 29th.
NEW ZEALAND/SOUTH PACIFIC
New Zealand’s temperature extremes during September ranged from a high of 25.5°C (77.9°F) at Waiau, South Island on September 30th to a low of -8.1°C (17.4F) at Mt. Ruapehu, North Island on September 13th. The greatest calendar day rainfall was 165 mm (6.50”) at Milford Sound on September 14th.
The coldest temperature in the southern hemisphere and the world during September was -84.2°C (-119.6°F) recorded at Vostok on September 16th. This will almost certainly also end up being the coldest temperature measured on earth for the year 2012.
KUDOS Thanks to Maximiliano Herrera for global temperature extremes data and Jeremy Budd and NIWA for New Zealand weather extremes.
Christopher C. Burt