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Cyclone Pam’s Toll Remains Uncertain; Great Plains Roast in Record Winter Heat

By: Bob Henson 3:14 PM GMT on March 17, 2015

Four days after Category 5 Tropical Cyclone Pam unleashed its fury on the island nation of Vanuatu, the full extent of damage and casualties is not yet known. Unsettled weather made it impossible for relief flights to reach many of the hardest-hit islands until Tuesday. The United Nations Office for the Coordination of Humanitarian Affairs attributed at least 11 deaths to the storm, revising its toll downward from an earlier estimate of 24 deaths. Somewhat ironically, the nation’s president, Baldwin Lonsdale, was attending the third UN World Conference on Disaster Risk Reduction in Sendai, Japan, when Cyclone Pam struck Vanuatu. In a news conference before returning home, Lonsdale referred to the cyclone as “a monster, a monster. It's a setback for the government and for the people of Vanuatu.” At its peak, Pam's 165 mph winds made it one of only ten Category 5 storms ever rated by the Joint Typhoon Warning Center (JTWC) in the waters east of Australia, and one of only two such storms to make landfall--the other being Cyclone Zoe of 2002, which struck the Solomon Islands. Pam and Zoe are the two most intense cyclones observed in the region since records began in 1970.

Some of the worst damage is expected to be found on the southern islands of Erromango (population 2,000) and Tanna (population 29,000), which were struck head-on by the stronger southeastern portion of the eyewall. Gusts may have topped 160 mph on the western sides of these islands, according to analyses by the British firm Tropical Storm Risk. On Tuesday, Australian military planes reported that more than 80 percent of structures on Tanna Island were partially or completely destroyed. The storm’s weaker southwest eyewall hit the island of Efate, and it appears the capital city, Port Vila, was just far enough west to avoid the worst winds. Still, aerial photos indicate many homes in Port Vila were destroyed, and some 15,000 people on Efate are homeless due to the storm.


Figure 1. This resident of Port Vila, Vanuatu, was injured when hit by masonry due to a shipping container breaking through a concrete wall during Cyclone Pam. Image credit: MR Roderick J. Mackenzie/New Zealand Defence Force, via Getty Images.


How you can help
Relief efforts for Cyclone Pam are still in the process of being organized, but food and water are among the most urgent requirements. The Weather Channel posted this set of agencies that are already welcoming donations to help those affected by Cyclone Pam:
• Red Cross Australia | New Zealand
• UNICEF
Australia | New Zealand
• Oxfam Australia | New Zealand
TEAR Fund
CARE USA
World Vision
Save the Children
Act for Peace

Was climate change a factor?
While there is no sign of any significant increase in tropical cyclone activity across the southwest Pacific in recent decades, Cyclone Pam developed over waters that were up to 2°C warmer than average, boosting the storm’s potential strength. The rise in sea level due to warmer oceans also exacerbates any ocean-related flooding produced by tropical cyclones. At Mashable, Andrew Freedman posted this comprehensive look at the connections between Cyclone Pam and climate change.

Records wilt after another day of summer-like heat across Central Plains
The hottest late-winter airmass on record across the central Great Plains sent temperatures on Monday to absurd values for mid-March. As a trough of low pressure strengthened over the northern Plains, westerly winds were driven downslope from the Colorado Rockies. Already very warm for the elevation and time of year, the air mass warmed even more as it descended toward lower elevations. Both Nebraska and Iowa saw the only 90°F temperatures known to have occurred before the spring equinox in more than a century of record-keeping at the states’ major reporting stations. The heat also persisted in California, where downtown Los Angeles endured its fourth 90°F day in a row--the first time any March has produced four 90°F days, consecutive or otherwise, in records going back to 1877.


Figure 2. High temperatures in the 80s and 90s were widespread across the central U.S. on Monday, March 16. Image credit: NOAA, via Florida State University.

Among the Monday records compiled by Jon Erdman and Nick Wiltgen of the Weather Channel:

All-time March records:
North Platte, NE: 91°F (previous record 88°F on Mar. 31, 1946)
Norfolk, NE: 92°F (tied record 92°F set on Mar. 22, 1910)

Grand Island, NE: 90°F (tied record set eight times before)
Warmest so early in the year:

Lincoln, NE: 90°F
Sioux City, IA: 90°F
Broken Bow, NE: 90°F

Goodland, KS: 89°F
Concordia, KS: 89°F
Omaha, NE: 88°F
Des Moines, IA: 84°F (tie)
Denver, CO: 81°F
Colorado Springs, CO: 80°F

Canada's Charlottetown and Saint John trump Boston in snowiest-winter sweepstakes
The same nor’easter that put Boston over the top for its snowiest winter on record produced the same result--with much more drama--in the largest cities of two Canadian provinces. By late Monday, the paralyzing storm had delivered an estimated 55 cm (21.7”) to the provincial capital of Prince Edward Island, Charlottetown. The city's official total snowfall on Sunday of 47.6 cm (18.7") sent the city’s snow total for the winter to 463 cm (182”), almost twice the total observed in Boston. Charlottetown’s previous seasonal record, 451.3 cm (177.7”), had been set just last winter. In the province of New Brunswick, Saint John climbed to a seasonal total of 431 cm (170”) on Sunday, beating the record of 424 cm (167”) set in 1962–63. Yet another storm will paste the Canadian Maritimes on Wednesday, bringing as much as 20 cm (8”) of additional snow to Charlottetown.

Bob Henson


Figure 3. Several feet of snow can be found in the backyards of Charlottetown, Prince Edward Island, where the latest snowstorm pushed the city’s seasonal snowfall total above 15 feet. Image credit: Ann Thurlow.

tropical cyclone Heat

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.