The water vapor loop shows that the pronounced tropical wave which moved into eastern Mexico yesterday continues to move westward. Several of the models are picking this feature up but weakening it and making it quite diffuse. However, it now shows up in the winds at several levels and will probably brush across at least southern portions of the state tomorrow afternoon and evening. I think that this will lead to a chance for severe storms tomorrow over the southern third of the state. P chart of the 1300 UTC sounding from Luke Air Force Base on July 25, 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 Storms did develop along the Rim and moved toward the valley. A weak outflow moved down toward the valley from the North, but did not appear to affect the temperatures or power loads for the valley.