Posted August 8, 2010, 8:49 PM.

In Temecula, July was the coolest in at least the past decade, with an average high temperature of 85.6°F more than a degree cooler than the next coolest July, 86.9°F in 2001. A similar start in August (with an average high of 86.6°F, four degrees below normal) would make it the coolest of the last decade as well, if it continues.

Hemet registered an average high of 94.2°F for the first week of August, two degrees below normal. July was only one degree below normal. Located just west of the mountains, the eastern valleys have not been as cool, with high pressure generally over the deserts so far this summer.

Fallbrook (80°F),, De Luz (81°F) and Murrieta (86°F) were a full five degrees below normal for the first week of August.

Riverside (89°F) was running four degrees below the normal average high.

Lake Elsinore (97°F), Menifee (95°F) were two degrees below average highs for August to date.

The cooler than normal weather is a by-product of a series of upper level low pressure troughs that have hung out of the west coast. The series of troughs have also mostly kept monsoonal moisture out the inland valleys, except for a few days in July. They've also led to a number of days with morning low clouds extending inland, something that is not frequent for this time of the year.

Forecasts from the Climate Prediction Center, however, have weather returning to normal in about a week, and perhaps venturing above normal for the rest of the month.