Light Showers Across Pima County

There were light showers and sprinkles across the area last evening and during the night. Most places recorded only a Trace (as we did here at house). There were 10 of 92 ALERT stations that recorded 0.04" or more for past 24-hours. These were in the Catalinas and the southwest sector of the network - 3 sites measured just over 3/10 of an inch.

This morning the tropical moisture plume has reached into the Southwest, with PW greater than an inch (greens) over most of southwestern Arizona (29 mm here at TWC this morning). The GPS system on campus has been down for quite a long while. Above is blended PW analysis from CIRA at Colorado State valid at 12 UTC.

The early WRF-NAM forecasts the plume to move across southern Arizona tomorrow and also to weaken as it does. Forecast below is of PW on the 5.4 km grid and is valid at 5 am MST.

The best chances for area-wide rainfall occur tomorrow as what is left of the Pacific cyclone moves across Arizona as a weak short-wave. The WRF-NAM forecast above is for composite radar echoes and is valid at 9 am MST on Thursday the 4th. Below is the WRF-NAM forecast of rainfall amounts through 11 pm on Thursday night, with some decent amounts forecast for lower elevations. Last rainfall here at the house was back on October 19th - so some real rain would be very nice.