Dry weather this morning will turn humid this afternoon as high pressure slides offshore and the wind starts coming out of the south. The high this afternoon will be right near the normal of 84 degrees. That means this month will be the 8th or 9th warmest July on record. July rainfall is going to wind up more than 1.5 inches below normal, and a far cry from the drenching we got in June.
Speaking of a drenching, we might have one tomorrow. The humidity is going to get thicker and thicker overnight and into Thursday. That may translate into a few showers tomorrow morning, but the best chance of rain late starts in the afternoon as a shortwave disturbance passes overhead and the jet stream switches from a flat flow to a trough. That jet stream configuration will work to pull the humid air near the surface upward and, in this case, probably cause a low pressure system to develop along the coast. The amount of humidity and lifting expected should result in showers and thunderstorms, some with heavy rain, from late Thursday afternoon into Friday morning. Tomorrow's high will only be in the upper 70s thanks to overcast skies.
Once that storm leaves Canadian high pressure will arrive and that should provide pleasant weather for the weekend. We're looking at mostly sunny skies with highs in the lower to mid 80s from Friday through Sunday.