A major winter storm will affect much of AZ through the rest of today lasting into the afternoon hours on Friday. The main disturbance, currently across central CA/NV, will continue to dig south into AZ while pulling moisture off the Pacific feeding a steady stream of shower/storm activity through the period. This long duration event will bring widespread light/moderate rain to the lower deserts and significant mountain snow above 3K-4K feet. Travel north and east into the high country during this time is not recommended with treacherous driving conditions and road closures likely.
For today plan on wet and soggy conditions with steady valley rain/mountain snow. Daytime temperatures will briefly warm into the 50˚F-52˚F range in between rain showers, but generally linger in the upper 40s. Breezy S/SW winds will hover in the 7-14mph range with greater localized gusts. The table below has precipitation details through Fri morning. We do expect to see localized runoff in area washes and possibly minor urban flooding (water ponding on roadways/low lying areas) later today into the overnight hours. However, with mainly snow expected above 3K-4K feet, this should limit a greater runoff/flooding threat along the foothills/higher terrain zones. Conditions will be monitored closely the remainder of the day and updates/statements will be issued if necessary.
For tomorrow plan on lingering convective showers into the afternoon hours. Some parts of the Valley could even see some frozen precipitation (graupel/sleet). High temperatures will again remain in the upper 40s to low 50s with continuing breezy conditions. We’ll have more tomorrow, but feel free to follow us on our social media feeds for the latest updates.