Tropical cyclones dot the northern hemisphere in the Atlantic and Pacific Oceans, but none is a serious threat to large land masses. However, one of them is a rare trans-oceanic wanderer which is moving up the list of long-lived storms.
Of more interest to most residents of the northern hemisphere is the change of season.
Fall began, by some definitions, on September First; by others, it will start September 21. But by any measure of the season, the weather pattern is changing from summer to winter, though it might not seem that way in toasty New York.
Let’s go Around The World.
Tropical Cyclone Season Hits Northern Hemisphere Maximum
The statistical peak of the Atlantic hurricane season is September 10. In the eastern Pacific, the maximum in late August has passed.
The western Pacific typhoon season, which runs all year, also peaks in August, but is often active in the fall.
Hurricane/Typhoon Kilo Will Probably Be In The Top Ten For Longevity
Tropical Depression Kilo formed far out in the eastern Pacific Ocean on August 20. It became a hurricane a few days later and, when it crossed the International Date Line, was classified a typhoon. Kilo is now a tropical storm, and this is its 19th day as a tropical cyclone. If the forecast is correct, Kilo will become the tenth longest-lasting tropical cyclone worldwide on Friday, and the seventh longest-lasting in the Pacific Ocean.
Kilo is forecast to curve out to sea east of Japan, then arrive in remote eastern Russia, never having reached any densely populated land area, though its moisture dumped unusual precipitation on Hawaii.
Tropical Activity In The Atlantic Basin
Tropical Storm Grace is following the path of two earlier cyclones across the Atlantic. She is forecast to weaken as she enters the Caribbean Sea. However, this system appears to be heading south of Hispaniola, which tore apart Erika.
If Grace survives the hostile conditions near the Caribbean islands, there is a chance it could develop in the western Caribbean. From there, storms sometimes make their way into the Gulf of Mexico.
An area of disturbed weather in the northern Gulf seems to have no future before it comes ashore in the Florida panhandle. However, this is a reminder that when the Cape Verde season is over, there is a secondary peak of Atlantic basin cyclone activity in the Gulf of Mexico and western Caribbean Sea.
Tropical Cyclone Activity In The Eastern Pacific
Hurricane Linda formed southwest of the Mexican coast and followed a common route parallel to the shore. At one time, forecasts gave Linda a chance to curve into Baja California, but now it is certain the storm will veer out to sea. Some moisture from Linda could work its way into southern California and Arizona, but most of the rain will probably fall in Mexico.
Western Pacific Relatively Quiet
With Kilo expected to curve east of Japan, the only other tropical threat is Tropical Storm Etau, expected to pass close to Kyoto.
Winds will probably be of moderate tropical storm strength — nothing this part of Japan isn’t accustomed to — and impacts should be minimal.
September Heat Wave Bakes Northeast
The downward bend in the jet stream that brought relief from the fire-inducing hot and dry weather in California last week has an associated upward bend in the east. Temperatures in the 90s have reached into central new England where normals for the dates are in the low 70s. Tomorrow will likely be the last day that any place north of Washington, D.C. sees the thermometer register 90 until next summer.
Record temperatures are possible in Boston and New York on Wednesday. After that, the jet stream pattern will reverse, with a dip in the east and a bulge in the west. Long-range forecasts show that this see-saw will continue, as the conflicting areas of warm water in the Pacific — El Niño in the tropics and the warm pool, sometimes called the ‘blob,’ in the Gulf of Alaska — battle for dominance.
Europe Has Cooled Since Summer Heat Waves, But Warmth Could Return
Much of Europe, particularly Spain, suffered through a record hot July. but August was moderate and the pleasant temperatures have continued into September.
The cause of the heat wave is thought to be a pool of cold water in the northeast Atlantic Ocean. The cold water cools the air above and lowers the pressure, inducing southerly winds over Europe.
Long-range forecasts indicate that the warm flow will return for the last half of September.
Snow In The US In Early September
The dip in the jet stream in the American northwest last week brought an unusual early-September snowfall to the mountains of Washington state. Snow in the high Cascades, which rise to 14,000 feet, is not unusual in September, but some places as low as 7,000 feet above sea level reported snow on Saturday.
The Season Is Changing Fast
Parts of South America, Africa, and Australia will welcome the increasing sunshine associated with the sun’s crossing the equator on the equinox. But in the northern hemisphere, winter is now in full view. Will it be like last year in Boston? Let’s just wait and see.
What are the changes taking place in your neighborhood?
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