Synopsis: A good portion of the County west and southwest of the Phoenix metropolitan picked up beneficial rains between a 0.10” and 0.33” on Tuesday. It really was a stark contrast between wet and dry conditions with Downtown Phoenix being the general west/east split. The best moisture lift tied to the low pressure circulation tracked too far south of Phoenix to include eastern portions of the County for rainfall. The cyclonic circulation has now even passed south of the International Border into the northern Gulf of California. This weather disturbance is associated with a larger upper level trough draped across the Desert Southwest and northern Mexico. It takes a couple days for the trough to lift northeastward and get carried away by the Westerlies. That leaves AZ in a seasonably cool and mostly sunny setup through Thursday. A West Coast high pressure ridge then exerts more influence heading into the weekend. Friday is looking fantastic in the Valley with cool mornings in the mid to upper 40s and widespread low 70s for highs. Occasional high clouds do spill over from the Pacific, as well.
Today: A dry and cool to start for the month of February. Morning lows are in the low to mid-40s. Mostly sunny skies and some breeziness (10-25 mph) out of the north over mainly higher terrain features are the weather highlights for the Valley. The threat for precipitation in south-central AZ has ended today, but the cooler air mass caught in a sluggish trough occupying the Desert Southwest prevents any kind of significant warmup for the time being. The afternoon will likely run a couple degrees below the seasonal norm of 69°F.
Thursday: Expect little variation in weather conditions from what is observed today. A more noticeable warmup begins entering Friday, just in time for the upcoming weekend.