Arizona DOT traffic camera on Interstate 10 west of Phoenix on Monday morning. (Weather Underground)

Update at 12:57 p.m. ET: Phoenix Sky Harbor International has now totaled 3.29 inches of rain since midnight on Monday, and scattered showers are still pushing through the region. This is by far the wettest day on record in the weather site’s 119-year reporting history.

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Severe storms pummel the Southwest causing flash flooding and power outages in California and Arizona. (Reuters)

It’s the wettest day on record in the Phoenix, Ariz., metro area Monday, as a surge of tropical moisture from former Hurricane Norbert is fueling incredible rainfall in the Arizona desert. Weather records in Phoenix date back to 1895.

Monday surpassed the rainiest calendar day on record at Phoenix Sky Harbor International, which has received over three inches of rain since the early morning hours. The previous record of 2.91 inches was set in 1933.

Putting this event into perspective, the National Weather Service in Phoenix writes that the average rainfall for the entire monsoon season is 2.71 inches.

Rainfall totals of two to four inches are widespread across greater Phoenix, and the deluge is not expected to let up until at least mid-morning, mountain time. Post-Tropical Cyclone Norbert, formerly a hurricane, is located off the Baja California coast on Monday morning, channeling warm, moist air northward into the Southwest desert, which is fueling the record-setting precipitation.


Mean sea level pressure and precipitable water from the ECMWF model, valid Monday morning. Norbert, formerly a hurricane, has been pushing tropical moisture (color scale) north from the coast of Baja California. (WeatherBell)

A flash flood warning is in effect until 10:30 a.m. MT in the greater Phoenix area as heavy rain is expected to continue there until mid-morning.

Dozens of schools are closed on Monday morning, and Arizona Public service has reported approximately 10,000 customers are without power, as well.

Images from Arizona Department of Transportation traffic cameras paint a grim picture of the early morning commute in the Phoenix area.