A classic severe weather set-up delivered Monsoon 2016’s most widespread metro storm event.
Much of southern Arizona woke up to cloud cover yesterday, which quickly eroded after sunrise. This set the stage for the Great Basin High pattern to work its magic. By early afternoon, thunderstorms were breaking out along the Mogollon Rim. Brisk 15-20 MPH steering winds at the mid-levels guided convection toward the valley floors of the Sonoran Desert.
Storms arrived in Tucson around 6 PM, as outflow winds in excess of 60 MPH tore through the eastern half of the metro. The bulls-eye for wind damage was centered near Davis-Monthan Air Force Base. Power poles were taken down near Camino Seco & Escalante, part of the reason over 20,000 Tucsonans lost electricity at the height of the storms.
In all, 9 severe wind reports were tallied by the Storm Prediction Center. Of these reports, Nogales registered the highest wind gust at 71 MPH around 5:10 PM.
The first round of storms exited Metro Tucson by 7:30 PM, followed up by two more rounds of storms during the late night hours. Officially, Tucson International Airport picked up 0.55″ rain. Places like the northeast metro, Catalina Foothills and Davis-Monthan AFB recorded 0.75-1.20″ rainfall. As quick as storms moved in, they exited. This helped mitigate any flash flooding issues.
Overall, a fairly well-forecast event yesterday. Primetime for metro storms was expected to be around 4-9 PM & that’s exactly what occurred. In hindsight, the third round of storms was under-forecast (I had 10%). However, overnight Monsoon storms are tough to pinpoint accurately due to subtle triggers in the atmosphere.