April 2013 Global Weather Extremes Summary
April was the coolest such since 1997 in the U.S. and since 1989 in the U.K. Flooding rains occurred in the north-central U.S. and in Argentina where 54 people died during a flash flood on April 2-3. Very heavy snowfalls occurred in South Dakota and Minnesota.
Below is a summary some of the month’s highlights.NORTH AMERICA
This past April was the coldest on record for North Dakota and in the top 5 such for much of the north-central portion of the U.S. it was also the coldest April on record for Fairbanks, Alaska where the temperature averaged 14.5°F (8.1°C) below normal.Generally a cold month across the country (the 23rd coldest overall April) with the exception of the Southwest.
The month also featured several historic snowstorms: 17.3” (44 cm) at Bismarck, North Dakota on April 14th was their greatest 24-hour snowfall on record (any month) contributing to the snowiest April on record for the city with a monthly total of 21.8” (55 cm). The airport location at Rapid City, South Dakota picked up 28.2” (72 cm) of snow on April 8-10, the greatest storm total in their records and leading to a monthly record total of 43.4” (110 cm). Duluth, Minnesota endured its single snowiest month (any month) with a 50.8” (129 cm) total (old record was 50.1” in November 1991). A snowstorm on April 19th left a calendar day record of 25.0” (63 cm): at Isabella, Minnesota, the state’s greatest such for the month of April.An all-time 24-hour snowfall buried Bismarck, North Dakota under a 17.3” blanket on 14th.
Photo by Tom Stromme, for the Bismarck Tribune.
Torrential rains in Iowa, Illinois, and Michigan on April 17-18 deluged a large area with 4-8” of precipitation resulting in record flooding for many of the rivers in the region. The heavy rains were partially responsible for Iowa and Michigan reporting their wettest Aprils on record. Grand Rapids, Michigan suffered serious flooding as a result of the mid-month storm and recorded its wettest April ever with a monthly total of 11.10” (282 mm). The same also occurred in Chicago where the April precipitation total of 8.68” (220 mm) edged out their previous wettest April of 1947 (8.33”/212 mm). In contrast, California continued its long winter-spring dry spell with the Jan-April period being its driest such on record. By the end of April the Sierra snowpack was just 18% of normalDry in the Northeast and West and wet in the Midwest and Southeast was the general pattern precipitation-wise this past April across the contiguous U.S.
The coldest temperature in the northern hemisphere during the month was -51.2°C (-60.2°F) at Summit, Greenland on April 18th.SOUTH AMERICA and CENTRAL AMERICA
One of the deadliest floods in Argentinean history occurred in the Buenos Aires-La Plata area on April 3rd following a deluge of over 175 mm (7”) of rain from thunderstorms that moved over the city and its suburbs. At least 54 deaths were directly attributed to the storms. For details on this event see my blog on the subject posted last month. Various modes of travel were employed to navigate the flooded streets of Buenos Aires following torrential rainfall on April 2-3.
Photo by Fernando Sturia.EUROPE
It was a cool month in most of northern Europe and with a hot spell mid-month affecting southern Europe where temperatures peaked at 34.5°C (94.1°F) at a site in Cordoba Province, Spain on April 17th. Cyprus saw readings as high as 36°C (97°F). The Balkans also saw some warm temperatures at the end of the month with April record temperatures of 34.0°C (93.2°F) measured at Banetski Kerlovae, Serbia and 32.5°C (90.5°F) at Zenica, Bosnia on April 30th.
In the U.K. it was the coolest April since 1989. The coldest temperature measured during the month was -11.2°C (11.8°F) at Braemar, Aberdeenshire on April 2nd and the warmest 23.1°C (73.6°F) at Faversham, Kent on April 25th. A fierce storm on April 17-18 brought a wind gust of 84 mph to Aberdaron, Gwynedd and caused an ancient and historic oak tree, known as the ‘Pontfadog Oak’ to topple in the Ceirog Valley of northern Wales. The tree had stood at least since 802 A.D. and was said to have served as a rallying point for a Welsh prince’s army that defeated England’s King Henry II in 1157 A.D. The storm also resulted in the heaviest 24-hour rainfall measured in the U.K. during the month: 63.6 mm (2.50”) at Lusa, Skye Islands on April 17th. The ‘Ancient Tree Forum’ paid its respects to the Pontfadog Oak during March 2012. The historic tree, said by some to be Britain’s oldest, was felled by a storm on April 17th.
Photo by Rob McBride.AFRICA
The warmest temperature measured in the northern hemisphere and the world during April was a reading of 47.0°C (116.6°F) at Matam, Senegal on April 16th. The Seychelles International Airport recorded 34.8°C (94.6°F) on April 10th, the warmest reading ever measured at an inhabited location anywhere in the Seychelles Islands.
Cyclone Imelda pounded Mauritius and Reunion Islands with heavy surf between April 5-10.ASIA
An extreme heat spell in Thailand and Laos resulted with a couple of all-time heat records being broken at two sites in Thailand on April 5th: 42.6°C (108.7°F) at Tha Phra and 41.6°C (106.9°F) at Chainat. The capital of Laos, Vientiane, reached 41.0°C (105.8°F), just 0.1°C (0.2°F) from attaining their all-time heat record. Port Blair, on the India’s Andaman Island, measured its warmest temperature on record with a 36.8°C (98.2°F) reading on April 19th.AUSTRALIA
It was another warm month for Australia, in fact the 8th consecutive month (since September) where both the minimum and maximum temperatures averaged above normal. Precipitation was slightly below normal.Temperature decile maps for April maximum temperatures (top) and precipitation (bottom). It was the 5th warmest April overall nationwide.
Maps courtesy of the Australian Bureau of Meteorology.
The extremes for the month included a 42.6°C (108.7°F) reading at Roebourne, West Australia on April 20th (this was also the warmest temperature measured in the southern hemisphere) and a low of -5.0°C (23.0°F) at Charlotte Pass, New South Wales also on April 20th. The greatest calendar day precipitation amount was 187.4 mm (7.38”) at Edith Farms Road, Northern Territory on April 1st.NEW ZEALAND
The widespread drought that had been plaguing New Zealand this past summer was largely broken by several periods of heavy rainfall. A very intense storm dropped 101 mm (3.98”) in one hour near Richmond, South Island on April 21st and 216 mm (8.50”) in 24 hours.
The warmest temperature measured in New Zealand during April was 31.0°C (87.8°F) at Gisborne, North Island on April 1st and the coolest -5.9°C (21.4F) at Ranfurly, South Island on April 10th.ANTARCTICA
The coldest temperature in the southern hemisphere and the world during April was -76.3°C (-105.3°F) recorded at Dome Fuji on April 3rd. KUDOS
Thanks to Maximiliano Herrera for global temperature extremes and Jeremy Budd and NIWA for the New Zealand extremes.
Christopher C. Burt