Phoenix 2019 weather: Was it a cool, dry year?
The numbers don’t tell the entire story on climate
At first glance, 2019 looked like a cool, dry, just-about-average year for Phoenix.
The year-end report from the National Weather Service office in Phoenix showed that the average temperature (when you take the average high and low and divide by two) of 74.9 degrees was 0.2 degree below normal while the official rain gauge at Sky Harbor Airport totaled 5.93 inches, 2.1 inches below normal. But those numbers didn’t tell the entire story.
While the temperatures turned out to be close to what we typically see (2019 ranked 28th warmest on the all-time list), that was because cooler-than-normal months early and late in the year were balanced out by a long, hot summer.
And when it came to rain, it seemed as if someone was holding an umbrella over the gauge at the airport while other parts of the Valley experienced plenty of wet days.
An up-and-down year
Mark O’Malley, a meteorologist with the National Weather Service in Phoenix, said 2019 was a series of peaks and valleys.
“One interesting stat we found was the first three months of the year were the coolest on record in Phoenix since 1998,” O’Malley said. “However, the monsoon was one of the hotter ones on record."
He also said the Valley and Arizona overall did fairly well during the monsoon and other rain events in 2019.
“When you look at the city as a whole, it was a little wetter than the airport would indicate,” he said. “If you look at precipitation maps there is a little hole around Phoenix where it was somewhat drier. But the suburbs away from the center actually had a wetter-than-average 2019."
The 3rd hottest summer on record
The average high temperature for Phoenix in 2019 was 86.2 degrees, which was a half degree below normal and 39th on the all-time list for that statistic.
The average low for the year was 63.6 degrees, which was a tenth of a degree above normal and tied for 22nd on the all-time list.
The first three months of the year were cool, with an average temperature of 58.7 degrees. Normal for January through March is 60.5. May was another cool month (the average temperature of 76.2 was 5.9 degrees below normal) before things began to heat up over the summer. June, July and August wound up being the third hottest summer (for meteorologists summer starts on June 1 and ends Aug. 31) on record with an average temperature of 94.9. The record for Phoenix in summer is 95.1 set in 2013 and 2015.
Cooler weather returned at year’s end, with October and December averages falling slightly below normal.
Though the year overall was close to normal, those cool months stood out when compared to recent history. Since 2010, Phoenix has experienced five of the 10 hottest years on record.
“When it comes down to it, last year was pretty much an average year,” O’Malley said. “It only seemed like it was cooler because the prior 10 years were so much hotter.
"If you break the year down, it started off very cool, May was very cool, the summer was very hot, and it got a little cooler toward the end of the year. It was kind of like this roller coaster of extremes where in a lot of the past 10 years, almost the entire year has been warm.”
A dry year? Not everywhere
According to the rain gauge at Sky Harbor, Phoenix was pretty dry in 2019 with only 5.93 inches of rain compared to the 8.03 inches that is normal for the city.
However, that wasn’t the case at several other National Weather Service reporting stations in the area:
❚ Deer Valley Airport was close to normal with 10.12 inches of rain. Normal is 10.76.
❚ Tempe got 10.36 inches, compared to its normal 9.33 inches.
❚ Litchfield Park had 10.36 inches
(1.03 above normal).
❚ An east Mesa station received 13.8 inches (2.15 over normal).
❚ Carefree recorded 16.83 inches (3.76 above normal).
❚ Apache Junction had 19.1 inches
(5.82 above normal).
O’Malley said much of that inconsistency was due to the nature of the monsoon. “That’s just the way the summer thunderstorms go,” he said. “That’s every year. There will be a year when the airport gets a deluge and the West Valley will get hardly anything. We’ve seen that before as well.”