Australia Avoids a Fire Catastrophe; Raymond Spares Mexico; Lekima a Cat 5

Sydney, Australia and the Blue Mountains to its west endured extreme fire weather conditions on Wednesday without catastrophe, as "aggressive" and "high-risk" fire fighting strategies kept the 71 fires burning in New South Wales from causing major devastation. "The broader risk to a much larger, more widespread population has certainly eased," said Shane Fitzsimmons, a fire official for the region. The fire conditions in the region were about as bad as it gets on Wednesday. The high temperature in Sydney hit 92°F, with sustained winds of 34 mph gusting to 47 mph, and a humidity as low as 4%. Temperatures are expected to be cooler on Thursday, but westerly winds blowing from the dry interior of Australia will still be blowing strongly, keeping fire danger extreme. Insurance claims from the huge fires that have ravaged areas just west of Sydney over the past week are already set to exceed $97 million (U.S. dollars), according to The Insurance Council of Australia, even though the worst-hit areas have not been assessed yet. This price tag already makes the disaster Australia's fifth most expensive fire on record, according to EM-DAT, the international disaster database. Wunderground's weather historian Christopher C. Burt has a new post on the history of Australian wild fires.


Figure 1. Smoke from fires burning over Southeast Australia streams out over the ocean near Sydney, Australia, due to strong westerly winds. MODIS photo taken at 03:15 UTC on October 23, 2013. Image credit: NASA

Fires worsened by Australia's hottest September on record
Australia has just had its hottest September on record, and the 12-month period ending in September 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 soil moisture levels in the lowest 10% historically for this time of year. However, the latest drought statement from the Bureau of Meteorology is not showing that long-term drought conditions exist.


Figure 2. Running means for the departure of temperature from average (the anomaly) for Australia for 12-month periods ending 31 August 2013. Vertical grid lines mark 12-month periods commencing January 1920, January 1930, etc. Australian temperatures are now, on average, more than 1°C warmer than during the 1950s. Image credit: Australian Bureau of Meteorology.

Climate Change and Australian fires
“Climate change is increasing the risk of more frequent and longer heat waves and more extreme hot days, as well as exacerbating bushfire conditions.” So said the independent non-profit Australia Climate Council in a report on the record September 2013 heat in Australia. In April 2013, the group (then called the Australia Climate Commission) published a report, "The Critical Decade: Extreme Weather", which gave an excellent overview of climate change and wild fires in Australia. According to the report, " many regions have already experienced an increase in extreme fire weather as indicated by changes in the Forest Fire Danger Index (FFDI). The main contributors to this increase are prolonged periods of low rainfall and the increased frequency and intensity of extreme heat. The FFDI increased significantly at 16 of 38 weather stations across Australia between 1973 and 2010, with none of the stations recording a significant decrease. The increase has been most prominent in southeast Australia, and has been manifest as a longer duration fire season, with fire weather extending into November and March. The opportunity for fuel reduction burning is reducing as fire seasons have become longer. Overall, this means that fire prone conditions and vulnerability to fire are increasing. The projected increases in hot days across the country, and in consecutive dry days and droughts in the southwest and southeast, will very likely lead to increased frequencies of days with extreme fire danger in those regions."

Australia's Climate Commission was defunded after the new government led by Prime Minister Tony Abbott took power in September 2013, writes Brian Kahn at climatecentral.org. However, the commissioners banded together and used crowd-funding to raise $1 million to start the non-profit Climate Council, a nonprofit organization aimed at providing climate information on Australia to the public. The Council is planning to release a report specifically about wildfires in November 2013. Australian Prime Minister Tony Abbott, who is a volunteer fire fighter, and famously said in 2009 that the science behind climate change is “absolute crap”. On Wednesday, he remarked: "Climate change is real, as I've often said, and we should take strong action against it. "But these fires are certainly not a function of climate change--they're just a function of life in Australia."

Raymond weakens to a tropical storm; threat diminishes for Mexico
Tropical Storm Raymond continues to spin just offshore of Acapulco, Mexico, but its top winds have weakened to 65 mph. As of 8 am EDT Wednesday, Raymond was stationary, and centered about 190 miles west-southwest of Acapulco. Raymond brought 7.05" of rain Saturday through Tuesday to Acapulco. All watches and warnings have been discontinued for the coast of Mexico, but Raymond is expected to bring an additional 1 - 2" of rain to the coast. Raymond is in an area with weak steering currents, but a ridge of high pressure is forecast to build in later Wednesday and force the storm west-southwestwards, away from the coast. Recent satellite loops show the weakening trend of Raymond, and wunderblogger Lee Grenci has a new post discussing the causes.


Figure 3. MODIS satellite image of Hurricane Raymond, taken at approximately 2:30 pm EDT on October 22, 2013. At the time, Raymond was a Category 1 hurricane with winds of 75 mph. Image credit: NASA.

Tropical Storm Lorenzo in the Atlantic no threat
Tropical Storm Lorenzo continue to head eastwards into the Middle Atlantic, and will not be a threat to any land areas. Satellite loops show that Lorenzo has a small area of heavy thunderstorms, which are being pushed to the southeast side of Lorenzo's center of circulation by strong upper-level winds out of the northwest that are creating high levels of wind shear. The shear is forecast to remain in the high range through Friday, which will likely destroy the storm by then.

Typhoon Francisco weakening, but will still bring heavy rain to Japan
Typhoon Francisco continues to weaken, due to cool waters and increasing wind shear, and is now a Category 1 storm with 80 mph winds. Francisco is traversing a large cool patch of ocean left behind by the churning action of Typhoon Wipha last week. Francisco will make its closest approach to Japan on Thursday and Friday, and will likely be a tropical storm undergoing transition to an extratropical storm. Although the latest computer model guidance keeps Francisco well offshore from Japan, the storm will still bring plenty of tropical moisture over Japan, which will be capable of causing mostly minor flooding problems.

Super Typhoon Lekima reaches Category 5 strength
The Western Pacific has made up for a slow start to its typhoon season, and has now cranked out its third Category 5 super typhoon of the year. Super Typhoon Lekima intensified to Category 5 status about 1,500 miles southeast of Japan at 18 UTC on Tuesday, joining Super Typhoon Francisco, Super Typhoon Usagi, and Tropical Cyclone Phailin as the four members of 2013's Category 5 club. Four Cat 5s is a fairly typical number of these top-end storms for Earth to experience in one year. Satellite loops show 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.


Figure 4. MODIS satellite image of Typhoon Francisco (left) and Super Typhoon Lekima (right), taken at approximately 02 UTC on October 23, 2013. At the time, Lekima was a Category 5 super typhoon with winds of 160 mph, and Typhoon Francisco was at Category 1 strength with 80 mph winds. Image credit: NASA.

Jeff Masters