Monsoon ends, El Niño on the way
People who felt the change in the air late this week were right: the monsoon officially ended Thursday in Arizona.
However, this winter could bring another rainy season as the National Oceanic and Atmospheric Administration announces the onset of another El Niño weather event.
A large low-pressure system ushered in windy, cooler and drier fall-like weather late this week, prompting the National Weather Service to confirm the end of the monsoon occurred Thursday. Wind is out of the southwest, another indicator.
The monsoon typically begins in early July and ends in mid-September here. The Weather Service disagreed with some other forecasters about when the monsoon started this year.
Rainfall in June through August at the National Weather Service's official measuring site in Prescott totaled 4.96 inches, or only 75 percent of the 108-year average of 6.57 inches.
September's rain looks as though it will be better. As of the end of the monsoon, it already was unofficially 1.94 inches or 113 percent of the average of 1.71 inches.
Prescott's forecast is for sunny skies through Friday, except for a 10 percent chance of rain Wednesday and Thursday.
The 2006 June through August period was the second-warmest on record for the continental U.S., at 2.4 degrees above the average, the National Oceanic and Atmospheric Administration announced Thursday. And the months of January through August were the warmest on record.
A blistering heatwave broke more than 2,300 daily records across the country in July. That included Prescott heat records or ties on July 21, 22 and 24.
At the same time that the National Weather Service made the call on the end of the monsoon, its NOAA counterparts announced the onset of a weak El Niño in the Pacific Ocean. This periodic warming in sea surface temperatures typically brings above-average precipitation and temperatures to Arizona during the winter.
The El Niño could strengthen into a moderate event by winter, forecasters said.
The last El Niño occurred only two winters ago, causing widespread flooding in Yavapai County.
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