|Mean, Daytime Diffs||−0.7||−1.2||−2.7||−4.0||−4.3||−6.8||−11.4||−12.4||−10.6||−3.3||−0.8||−0.9||Valley is warmer in the day, esp in Summer||Mean, Nighttime Diffs||5.4||4.7||2.8||1.4||2.4||1.9||0.6||−0.4||1.1||1.9||7.2||4.1||Valley is colder at night, esp in Winter|
The daily daytime SD's vary between 3 degrees (winter) and 5 degrees (summer). The daily nighttime SD's vary between 2 degrees (summer) and 3.5 degrees (winter).
The main difference "boils" down to about 10 degrees warmer weather from Jul through Sep (85 instead of 75). The rest is modest—difference that can be felt in benchmark direct comparisons, but that you would not notice day-to-day.
Define Summer as approximately June through October; winter as approximately Nov through April. Visually: