Midlevel flow is very moist, but the lower desert is quite dry. The Phoenix sounding is drier at 500 mb than any of the nearby soundings and is stable. A large MCS occurred during the night over Sonora and may indicate that low level moisture is nearby. Flow aloft above 400 mb is northwesterly and fairly strong. P chart of the 12 UTC sounding from Luke Air Force Base on July 10, 1994.
Wind speeds are in knots.
The small box indicates the location of Phoenix, and the Salt and Verde River Basins are outlined. Observed Weather Isolated thundershowers occurred over the northeast and southeast areas of the state with a bit higher coverage over the White Mountains.