The past week featured an over-hyped celestial disappointment, the strongest hurricane ever in the month of May, sandstorms in China, and a deluge in Texas.
Coming up: the World Cup starts in Brazil in two weeks, the jet stream stays stuck in a ‘blocked’ pattern, and summer starts with a heat wave in India. Let’s go around the world.
The Camelopardalids: A Lot Of Lost Sleep And A Few Good Meteors
The Camelopardalids, a much-ballyhooed meteor shower, was generally considered a bust, despite good viewing conditions in large parts of the US and Canada.
There were a few streaks of light, and a handful of long and spectacular trails. But the hoped-for explosion of shooting stars did not materialize. As Decoded Science reported on Friday, these meteor events are notoriously fickle. This one depended on Jupiter tugging the debris from the long-ago passage of a comet into the earth’s orbit. He apparently didn’t pull hard enough.
Hopefully this disappointment won’t deter anyone from trying to view the next good meteoric display: the Perseids in mid-August. That meteor shower is much more reliable than the Camelopardalids — and certainly easier to pronounce.
Hurricane Amanda Sets A Record
Hurricane Amanda formed off the south coast of Mexico on May 24, and rapidly intensified into the strongest hurricane ever observed in May.
Top winds just brushed up against category five status (157 miles per hour or greater). As of the 5 a.m. (EDT) advisory on May 27, Amanda was still a category three storm, with top winds of 125 miles per hour. The storm will weaken rapidly, and dissipate within a couple of days. However, the moisture from Amanda could reach the southern US by the weekend.
Flooding In Texas
The slow-moving weather system which has barely budged from the southwest for many days has dropped more rain on most of Texas since May 10 than fell in all of 2014 prior to that date. The rain is bringing some relief from the severe drought, but in many spots it was too much of a good thing, with flash flooding occurring as up to three inches of rain fell in a single hour. As the trough that’s causing this weather moves slowly east, rainfall, possibly enhanced by the moisture from Amanda, could be heavy across the southern states for the rest of the week.
Sandstorms In China Worst In 18 Years
Sand blowing over northwest China from the Gobi Desert in Mongolia is common in the spring. But the sandstorm on May 25, 2014 was the worst in 18 years, prompting schools to close and residents to wear masks, as the sand was so thick that it reduced visibility to 50 feet. The sand sometimes reaches Beijing, though the effect there is less noticeable, since smog is normally so heavy that the sand is just an added nuisance.
World Cup Weather
With the World Cup only two weeks away, there is almost as much attention focused on the weather forecast as on the readiness of the stadiums.
One of the reasons Brazil was chosen for this event was the likelihood of Goldilocks weather — not too hot, not too cold, not much rain. Last week, the temperature nudged 90 degrees in Rio, but July is the dead of winter in the southern hemisphere, with its marine-tempered climate (81% of the southern hemisphere is ocean; average water temperature at Brazil’s latitude is 72 degrees).
This should guarantee moderate temperatures and light rainfall, as Brazil is in a zone of dry weather that circles the globe. In the United Sates, only the desert southwest gets less rain in July than Rio’s inch and a half. Light precipitation occurs about one day in four, but heavy rain only one day in a hundred.
Indian Heat Wave And The Coming Monsoon
May is normally the hottest month in India, as residents await the cooling effect of monsoon rains. This year is hotter than most, with temperatures routinely passing 110 degrees in the center and north of the country.
The temperatures in India have generally been above normal all winter, in keeping with the trend of warm weather everywhere except in the continental United States. The daytime high temperature in Mumbai has now reached or exceeded the average for 100 consecutive days.
The forecast calls for temperatures to exceed 115 degrees in inland locations before the monsoon begins in early June.
The Jet Stream Is Temporarily Out Of Order
Instead of the normal west to east motion with embedded waves, the current jet stream features many closed vortices: Omega blocks and cutoff low pressure centers. These features move only very slowly and the weather has been stuck for several weeks. The features that are causing heavy downpours over Texas and the heat wave in India will persist for at least several more days. The forecast for the next three weeks indicates the sluggish pattern will continue well into June.