We called for a 30% chance of scattered storms through midnight. We did not anticipate activity lingering well into the overnight hours for Metro Tucson. So what happened?
Above is the Tucson upper air data from 5 PM yesterday. The area between the dark red dashed line and red solid line indicates an unstable atmosphere. As great meteorological mind Bob Maddox pointed out in his blog earlier today, considerable lift was needed to get storms fired up. Thanks to repeated rounds of mountain storms, outflow winds provided the needed lift.
For much of Tucson, last night was a saguaro soaker. Over 0.75″ rain officially at the airport between 5 PM Monday and 3 AM today. The mountains were crushed with 2-5″ of rainfall, which caused some running washes/streams during the morning commute. Casa de Beamish in Oro Valley received 1.25″ rain, with the bulk of it coming down around 1 AM. I know the timing because it woke me & my family up! Click here for the complete list of rain totals compiled by the fine folks at NWS Tucson.
Not too many severe wind reports from last night, but a pair of microbursts took down trees in Oro Valley and near La Paloma. Phoenix took the brunt of the nastiness, with 30 severe wind/damage reports. Many of these reports came from the Arizona State Fairgrounds area & around Arizona State University. Colleague Dr. Matt Pace at 12 News says last night’s storms in The Valley have a 4-20% chance of happening every year. This is the second time in as many weeks Phoenix saw a widespread severe wind event.
With hindsight being 20/20, I’d grade my Tucson forecast from yesterday with a “C-“. We saw the scattered action. But the timing was off & it had a bit more of an impact than expected.