Atmospheric Happenings: October 26 – 27, 2010

Weather map showing the lowest barometric pressure of record not involving a tropical cyclone, as it was recorded on 26 October 2010 at 1129 EDT

Yesterday in the heartland USA National Weather Service meteorologists reported having meassured the lowest atmospheric pressure of record not involving a tropical cyclone; a reading of 956 mb was recorded yesterday at 1129 EST in a sector of the storm front reaching from Alabama to Michigan that moved toward the east spawning tornadoes, rain and thunderstorms across a large region of the country.

This record drop in atmospheric pressure appears to be one more extreme eventof the several we have witnessed in recent years, which at least anecdotally appear to be on the increase. Empirical information points to extreme rain events throughout the country, while in other regions drought continues, also shorter but colder and more violent winters over the past few years, and more tropical cyclones reaching category 5 worldwide or undergoing  rapid intensification on a yearly basis. While this is unscientific as a method for determining if extreme weather events have indeed been increasing, it merits our attention and closer study to see if these are indicators of things to come.

Typhoon CHABA moving toward Japan on 27 October 2010 with sustained winds of 127 mph.

Also over the past couple of days just as we say hurricane-tropical storm-tropical depression Richard go over Belize, Guatemala and the Yucatan peninsula to eventually dissipate over the western Gulf of Mexico, we saw the strengthening of tropical cyclone Chaba into a category 3 typhoon as it aims for some of the most populated areas of Japan. And for the first time in several months during 2010 we see a tropical wave generating south of the equator, this one over the Indian ocean, which appears to be strengthening in route to becoming a tropical cyclone on the next day or two. From all of this we can conclude that the tropics continue to be active even as such activity may be shifting from the northern to the southern hemisphere.

Color enhanced infrared satellite view of the Indian ocean on 27 October 2010 showing a strengthening tropical vae about 10 degrees south of the equator, the first such instantance of potential cyclogenesis south of the equator over the past several months of 2010. This appears to potentially mark the initial stages of the "2011" south Indian Ocean hurricane season.

Satellite view of the Atlantic basin for the aviation industry. Marked by the yellow outlines are the three areas of disturbed weather that are showing some potential for further development, which warrant monitoring in days to come. This view also shows the ares of rain and thunderstorms that have been present over Central America and northern Colombia and Venezuela over the past 3 - 4 months.

Shifting our attention back to the larger Atlantic basin on 27 October 2010 we see three waves of disturbed weather, with some potential for tropical cyclone development, which are active over several areas of the Atlantic including one off the coast of northern Brazil almost straddling the equator.

Looking toward the east we see a continuous chain of tropical waves and areas of rain/thunderstorms reaching from the eastern Pacific just off the coast of Nicaragua all the way through Hurricane Alley, the eastern Atlantic and across equatorial Africa. While most of these cells of disturbed weather are larger than those seen just last week, they also appear to be growing closer to  and even beginning to straddle the equator as the shift in seasons marked by the autumn equinox just about five weeks ago is bringing more on the southern hemisphere under more sun light as time progresses toward the winter solstice and the end of 2010. Are these various tropical waves and cells of disturbed weather over the Atlantic signs of what we may expect from a waning 2010 Atlantic hurricane season? Or just some last flashes of tropical activity that may pose no threat to our interests here in Florida and other Gulf or Atlantic USA coastal regions? Only time will tell, meanwhile we’ll do good to monitor these systems closely, to pay attention! To be prepared!! To MITIGATE!!!

Composite satellite view creating a global mosaic from the eastern Pacific to the Indian Ocean showing water vapor in the atmosphere, on 27 October 2010, which helps us visualize those waves and disturbed weather cells that warrant closer monitoring for signs of potential further development in days to come. Notice the region of rain and thunderstorms over Central America, which appears to have been ever present for the past several months, courtesy of La Nina.