Napa Valley Weather: Napa Valley July Weather
July in the Napa Valley starts off with a bang as the annual July 4th parade ushers in the holiday in downtown Calistoga. This is truly a community event and has a long and colorful history of floats, bands and all out fun. Put your chairs out early and stake your claim on the sidewalk for the best view in the house. The Napa County Fair runs through July 4th and offers world-class music acts and every thing from a Destruction Derby to a Rodeo.
In the town of Napa, the average temperature in July is 68 degrees, while the average high is 82 degrees and the average low temperature is 51 degrees. The average rainfall for July is 0.1 inches. Temperatures and rainfall in Yountville and Oakville, several miles north of Napa, would be roughly the same as in Napa.
In July, the average temperature in Calistoga is 71 degrees, the average high is 88, and the average low is 52 degrees. The average rainfall in Calistoga for July is 0.1 inches. These figures reflect a close approximation to those in St. Helena, just eight miles south of Calistoga.
July truly marks the beginning of Summer in Napa Valley, with daytime highs in the 80’s and sometimes exceeding 90 degrees. Temperatures will be several degrees warmer as you head north from Napa. However, regardless of how hot it gets during the day, the temperatures will invariably cool down substantially during the evenings to the mid 50’s and even the 40’s. It is ideal sleeping weather, and it will be the rare night in July when air-conditioning is needed. Moreover, if you are coming from the east or mid-west, and are used to humid summer days, you will be pleasantly surprised to learn that the summer climate in Napa Valley is extremely dry, with little or no humidity.
If you are planning to watch the 4th of July fireworks, you might consider bringing a light sweater, as chances are excellent that temperatures will dip to to the 50’s during the evening.