July Rainfall Summary - Updated

First some data from here and several others who sent me their totals for July. At the house (just northwest of intersection of Prince and Country Club) I measured only 0.60 inches. In my 17 years of record here this is the second driest July, with driest being 0.49 inches in 2000. There was measurable rain on 9 days, but maximum daily amount was only 0.11 inches on two different days. During the summer such a small amount will keep the top soil damp for only minutes to an hour during the day. It's not surprising that when I walked this morning open soil along the Rillito remains powder dry. Other reports:

Russ Scott - 1.14 inches - (near Tucson and Glenn)

Ron Holle - 1.64 inches - (in Oro Valley, bit north of Naranja and just east of La Cholla) 

Jim Toth - 1.27 inches - (about 1.25 miles northeast of 1st & River)

Santa Rita Abbey (from Sister Pam) - 3.09 inches (about 5 miles north-northwest of main junction in Sonoita)

Art Douglas - 6.14 inches - (Ash Canyon, elev. 5200 ft, south of Sierra Vista and west of Hereford)

The monthly totals from the Pima County ALERT network provide a nice overview of rainfall totals for July across the metro Tucson area and nearby mountain/desert locations. The metro west sector above shows the dry hole in north part of city along the Rillito.

The 0.04 inches for the Santa Cruz at Valencia site appears somewhat suspect, with rain measured during only one hour during the entire month.

The Catalinas sector (below) indicates a wet month over the mountains, but with only Mt. Lemmon site coming in wetter than Ash Canyon, which is at a much lower elevation than Mt. Lemmon.

The metro east sector (above) indicates another dry zone in the southeast part of city along I-10 (see sector at bottom also). The southwest sector (below) shows a nice wet area over the Santa Ritas and to the west of the mountains, where elevations are somewhat higher. At bottom, the southeast sector (with few gauges) shows higher rain amounts along the east edge of the network. 

If we don't consider the gauge with 0.04 inches, there is still over an order of magnitude range for the July rainfall totals - very hard to generalize the character of the month for eastern Pima County, given this kind of variance.