The week is full of weather news.
Hot, then rainy in Brazil, but clearing in time for the start of the World Cup; a new tropical storm; iffy weather for a space launch; choking heat in Arizona and smoke in Florida; monsoon relief from the heat in India — and more. Let’s go around the world.
World Cup To Start With Perfect Conditions; Give The Weatherman Credit
The start of the World Cup is just two days away. Meteorologists, after much waving of magic wands and genuflecting to the weather gods, are confidently predicting fine weather in Brazil for the most famous sporting event in the world.
No repeat of the past weekend’s ninety-degree heat is anywhere in the forecast; a weak low pressure system moving through the area today with showers should be well away by the time of Thursday’s opening match between Brazil and Croatia.
The Indian Monsoon And A Temperature Reversal
Monsoon winds from the Indian Ocean are just reaching some of the rainiest and hottest places in the world. India has five seasons: fall, winter, spring, summer, and monsoon. Temperatures peak in May (summer), and monsoon begins from early to late June, depending on the location and the particular year.
Delhi, the Indian capital located in the interior north of the country, has been sweltering: The last five days have seen temperatures soar over 110, and the forecast is for another five of the same — then the wind will shift. Strictly speaking, a monsoon, though associated in the public’s mind with rain, is a wind phenomenon. When the wind shifts from north to south in Delhi, there will be no rain — but the temperature will fall more than ten degrees because the new wind direction will bring air that crossed the cool Indian Ocean.
Though the monsoon wind will be moisture-laden, there will not be enough instability in the atmosphere to cause anything but occasional showers. The heavier rain, still modest by monsoonal standards, comes to Delhi in July and August.
Cherrapunji, in the far east of India and much closer to the ocean than Delhi, receives nearly a thousand inches of rain per year, most of it in the monsoon months. The onset of the monsoon drops the temperature about fifteen degrees. That onset occurred yesterday, and with it the downpours started.
Why does Cherrapunji get so much rain and Delhi so much less? While Delhi is only 600 feet above sea level, Cherrapunji is at elevation 5,000 feet in the foothills of the Himalayas. No need to wait for instability here; the motion of the air up the mountain forces the water vapor to condense and fall as rain, because temperature drops with altitude and cold air cannot hold as much water vapor as warm air.
Cherrapunji’s daytime maximum temperature has rarely been below 85 degrees for the last three months, but for the next month the mercury is not likely to rise above 80. And it will rain every day in a biblical deluge.
Western US Heat Wave
Inland California, all of Arizona, and parts of New Mexico and Nevada are sweltering; temperatures are five to ten degrees above the normal (which is hot enough at this time of year). Death Valley reached 120 degrees on Monday, and Phoenix could top 110 today.
The forecast shows the possibility of cooler air moving in later in the week, with temperatures declining to the comfortable (all things are relative) high 90s in much of the desert.
Trouble In The Tropics
The pool of very warm water south of the southern coast of Mexico has spawned another tropical storm, Cristina, which will probably become the second hurricane of the eastern Pacific season on Wednesday. As Amanda (the season’s first hurricane) did, Cristina will eventually face a hostile environment as it moves west and northwest over much colder water. The storm is no threat to land and will weaken and dissipate by the end of the week.
June is normally an inactive month for tropical development in the Atlantic basin. Right now, water temperatures are below normal in much of the Gulf of Mexico, which is where we would expect to see most of the action in June.
There is no correlation between the number of June tropical storms and the activity for the rest of the season.
Florida Weather News, Column One: A Space Launch
A SpaceX Falcon 9 rocket will take off from Cape Kennedy Thursday night to put six communications satellites into orbit. Anyone within about 200 miles can see the rocket trail if the sky is clear.
The rainy season has not set in yet in south Florida, though showery weather is increasing. It is possible that the launch will go off without any threatening weather, but thunderstorms can pop up any afternoon and some can produce strong winds and frequent lightning. If the launch has to be delayed, the window for getting off the ground closes at 10.01 p.m.
Florida Weather News, Column Two: Brush Fire
At the southern end of the state, Gold Coast residents woke up Monday to choking smoke, courtesy of a wildfire in the Everglades, which is starved of water and partially covered with dry vegetation. In its pristine condition, the Everglades was a ‘river of grass,’ with water flowing slowly year-round. After the confinement of Lake Okeechobee, conversion of land south of the lake to agriculture, and the diversion of water to the crops, the river of grass became a parched brush waiting for a fire to happen, especially in the late spring and early summer — after the dry winter and before the heavy rains of summer.
Some rain fell Monday afternoon, and as soon as the rain sets in for real, the smoky season will be over. But the many problems created by the diversion of water from the Everglades and the confinement of Lake Okeechobee will continue: Salt water intrusion; Destruction of estuaries on both coasts by dumping of water when the lake level gets too high; Continued loss of wildlife habitat. It is unlikely that the Everglades can ever be restored to anything like its natural condition.
This Week’s Weather
From smoky conditions in Florida to cooler temperatures in the desert, this week’s weather will have a little something for everyone. What’s the weather like where you’re located?
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