Today should be the last day without chance precipitation in the forecast. Expect breezy but warm conditions today. A series of weak weather disturbances (troughs of low pressure) will move across Arizona over the coming week. The result will be cooler
temperatures and periods of scattered showers and thunderstorms through Sunday.
Additional notes for the weather nuts out there:
This series of troughs is seen on one of our products from the GFS model,
This represents flow patterns and precipitation at 500 mb (about 18,000 ft). The air moves pretty much parallel to the black contours, from west to east. A trough of low pressure is where the flow is turning cyclonically (counterclockwise). As these upper troughs move over our location, the atmosphere often becomes unstable (less resistance to vertical motion) making showers and thunderstorms possible. The forecast amount of precipitation is indicated in the legend below the map. Because this model is at a fairly coarse spatial resolution, precipitation amounts are overly optimistic J. You will also note a tendency for troughs to form over Arizona during the current week. This will keep us a tad on the cool side. The stronger the upper trough, the cooler the weather. As you can see from the loop, most of the weather action (precipitation) happens under upper flow from the south or southwest, just east of these troughs. This is typically the case for mid-latitude upper troughs.
Dr. Mark Sinclair