AZ Monsoon: Historic Rain Event Expected In Tucson; NWS

TUCSON, AZ — A potentially historic rain event is expected to hit the Tucson area Thursday afternoon, lingering through Saturday.

That's the takeaway from National Weather Service meteorologist Rob Howlett, who compared the upcoming weather pattern as being the first true monsoon flood event to hit the region since the 2006 floods.

The 2006 event saw 10.6 inches of rain fall on top of Mt. Lemmon on July 31 alone, producing devastating flooding across the region.

"There's going to be multiple rounds [of rain] Thursday through Saturday, including during the overnight hours," Howlett said. "And that's one of the things that we really want to stress here. We're all used to those typical [monsoon] time frames of the afternoon and evening, but we're looking at a good chance of having nocturnal events as well."

A flash flood watch has been issued for all of Pima, Cochise, Santa Cruz, Graham, Greenlee and Pinal counties, from Thursday through Saturday evenings, in connection with the storms.

Certain areas of Southern Arizona will see more rainfall than others, Howlett said, with a potential for anywhere from three-to-five inches of rain over the three-day period.

Storms will be capable of producing winds in excess of 40 MPH, with flash flood warnings expected for the region as the week progresses, Howlett said.

"Our take-home message really is that all of our guidance is showing us that this is going to be an unusual event, compared to what we've seen," Howlett said. "So all the indicators are there that we should see an unexpected amount of rainfall."