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Australia Endures Another Dangerous Fire Weather Day; Lorenzo Dissipates

By: Dr. Jeff Masters, 3:23 PM GMT on October 24, 2013

Sydney, Australia and the Blue Mountains have endured a second day of dangerous fire weather conditions without a devastating fire catastrophe ensuing. The high temperature in Sydney on Thursday hit 73°F, with sustained winds of 30 mph gusting to 41 mph, and a humidity as low as 7%. The temperature was nearly 20°F cooler than on Wednesday, but the strong winds and low humidity helped fan the 56 fires still burning across the state of New South Wales. Tragically, a fire-fighting aircraft crashed Thursday during a mission to douse one of the fires, killing the pilot and starting a new fire. The fires have burned more than 120,000 hectares (300,000 acres), and have a perimeter of about 1,600 km (990 miles), and are being blamed for two deaths and over $97 million in damage. Australia has just had its hottest September on record, and the 12-month period ending in August 2013 set a record for the hottest 12-month period in Australian history. Australia's warmest summer and 3rd warmest winter on record occurred during this 12-month period. It has also been quite dry in the fire region over the past few months, with sol moisture levels in the lowest 10% historically. However, the latest drought statement from the Bureau of Meteorology is not showing that long-term drought conditions exist.


Figure 1. Volunteer Christelle Gilmore cares for 'Phoenix', an orphaned baby Swamp Wallaby burned in the Springwood fires on October 22, 2013 in Castlereagh, Australia. Photo by Brendon Thorne/Getty Images.

Raymond weakens, moves away from Mexico
Tropical Storm Raymond continues to move away from the coast of Mexico, and will no longer bring heavy rains to the country. Recent satellite loops show that Raymond is a poorly-organized tropical storm, with just a modest area of heavy thunderstorms.


Figure 2. Rainfall over Mexico from October 15 - 23 from Hurricane Raymond totaled close to 10" near Acapulco, as estimated by NASA's TRMM satellite. Fortunately, Raymond did not move ashore, or else the 15+" inches of rain that fell offshore would have fallen over land. Image credit: NASA Goddard Space Flight Center.

Tropical Storm Lorenzo dies in the Middle Atlantic
Tropical Storm Lorenzo has died in the Middle Atlantic, done in by high wind shear. None of the reliable computer models for tropical cyclone genesis are predicting any new storms developing in the coming five days. During the first week of November, the Madden Julian Oscillation (MJO), a pattern of increased thunderstorm activity near the Equator that moves around the globe in 30 - 60 days, will bring rising air over the Caribbean, increasing the odds of a tropical storm developing then.

Typhoons Francisco and Lekima weaken
Typhoon Francisco has weakened to a tropical storm, and is bringing heavy rains to Japan as it stays offshore and heads northeast, parallel to the coast. Super Typhoon Lekima, which stayed at Category 5 status for a day and a half, has now weakened to a Category 4 storm with 150 mph winds. Satellite loops show that Lekima is still an impressive typhoon with a prominent eye surrounded by a solid ring of eyewall clouds with very cold cloud tops. Lekima is predicted to recurve to the northeast without affecting any land areas. While Lekima was at peak strength between 12 and 18 UTC on Wednesday, its eye expanded greatly in size while the storm stayed at Category 5 strength, something that is very unusual to see (thanks to Scott Bachmeier of the University of Wisconsin CIMSS for the info and animation.)


Figure 3. MODIS satellite image of Super Typhoon Lekima, taken at approximately 01:05 UTC on October 24, 2013. At the time, Lekima was a Category 5 super typhoon with winds of 160 mph. Image credit: NASA.

Jeff Masters

Fire Hurricane

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