At 10:29 p.m. Eastern Daylight Time on September 22, the sun will shine directly down on the equator a little north of Papua New Guinea. This event will usher in astronomical fall (meteorological fall started Sept. 1) in the northern hemisphere.
The Equinox: September 2014
September 22 will be the day of the equinox — equal night — although if you look for times of sunrise and sunset in New York City, you will find the date on which they are 12 hours apart is September 27. This is because sunrise is most commonly defined as the time when the first ray of sun appears and it takes a few minutes for the disk (more relevantly half the disk) of the sun to rise (and set).
At the equator, there is actually never any equal night and day by the definition commonly used. Once you get far enough of the equator to have an actual equal night, the date on which it occurs gets later with increasing latitude.
Most people probably don’t care exactly when the equinox occurs, astronomically, meteorologically, or rhetorically. They just want to know if it will be a cold winter.
Decoded Science will only predict that this winter will not be as severe as last. Though the weather pattern that caused such havoc in the central and eastern US last winter has persisted through the summer, there are signs of change. The polar vortex looks like it wants to migrate eastward. The incipient El Nino, which has waxed and waned in the last month, could tip the balance and make winter rainy rather than snowy across much of the US.
So far, the jet stream has stubbornly kept a ridge over Europe, but changes in one part of the globe affect many others. Currently the jet stream has established a wave pattern that allows the broad ridge over Europe to remain in place, and the temperatures over the continent will remain above normal for the foreseeable future..
Hurricane Edoouard is far out in the middle of the Atlantic Ocean and no threat to land. It has reached category three status, making it the first major hurricane of the Atlantic season. Edouard might eventually curl back to the southwest and impact the Azores Islands, but no mainland area will be affected.
Hurricane (Now Tropical Storm) Odile
Odile is the real deal. The hurricane tracked northwest, tantalizingly close to the Mexican coast, then nudged just far enough to the northeast to smack the southern tip of Baja California with a nasty blow. Blossoming quickly as it approached Cabo San Lucas, the storm reached category three strength of 125 miles per hour at landfall.
Odile is now a tropical storm over the central portion of Baja, which is largely uninhabited, but the focus of interest is on the moisture associated with Odile and whether it will impact the southwest US, as Norbert’s moisture did just last week.
Current forecasts call for the remnants of Odile to move into southern Arizona on Thursday; the circulation should still be discernible on Friday in east-central Arizona.
Arizona and New Mexico could be subject to a deluge equal to or even greater than the one from Norbert (which was augmented by the remnants of Gulf of Mexico Tropical Storm Dolly). Southern California might get some beneficial rain, but not nearly enough to alleviate the drought.
Tropical Storm Polo
Yet another tropical cyclone has developed in the breeding ground south of Mexico. Tropical Storm Polo will roughly follow the path of Norbert and Odile, but at this time the path is expected to be seaward enough to keep the storm away from Mexico.
The Philippines are often affected by hurricanes, so by their standards, Kalmaegi might be considered run-of-the-mill. But though it didn’t pack the punch of last year’s Super-Typhoon Haiyan and this year’s Super-Typhoon Rammasun, both with winds over 150 miles per hour, Kalmaegi still managed to kill ten people and cause widespread damage to the rice crop.
Top winds were ‘only’ 81 miles per hour, and the storm passed through rather quickly — 20 miles per hour — which helped minimize damage.
Kalmaegi is not done. The typhoon weakened a little due to its interaction with land, but then entered the South China Sea, where water temperatures are high. Fortunately for those in the path of Kalmaegi, atmospheric conditions were not conducive to strengthening, so the storm is a minimal typhoon as it enters China and then Vietnam.
Businesses are closed in Hong Kong today, and the storm center will pass within 40 miles of Hanoi on Wednesday with tropical storm force winds near the center. Flooding rains will accompany the circulation far inland across northern Vietnam and China, with rain especially heavy in the mountains.
The Search for MH370
Fifty-six ‘hard objects’ have been identified by sonar in the Indian Ocean west of Perth, Australia. They could be debris from missing Malaysian Airlines flight MH370, or they could be debris from a ship, or they could be just rock outcrops. The weather should improve in the search area as spring sets in. Still this is the hostile Indian Ocean, and even in midsummer, seas are typically rough. They call this the roaring 40s (for the latitude), and there’s a reason.
Scottish Referendum On Independence
The Scots will vote on whether to change their national address from United Kingdom to Scotland on Thursday. The weather should be conducive to a big vote: temperature in the 60s with just a chance of some spotty rain. Which side this helps we don’t know, but the election is forecast to be very close.
Keep An Eye On The Weather; It’s Interesting
The season is changing fast. Every day brings something new to see, weather-wise. What’s going on where you are?
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