TIMELINE: Record highs almost certain again with dangerous heat risk across Bay Area

SAN FRANCISCO (KGO) -- Heat risk is major to extreme Wednesday with the extreme risk in our hills as the Bay Area heat wave enters its third day.

WATCH: Heat wave vs. heat exhaustion - how to tell the difference

Meteorologist Drew Tuma explains the symptoms of heat stroke and heat exhaustion -- and how to tell the difference.

There will be widespread 90s and 100s Wednesday afternoon with record highs almost certain again.

There will also be moderate to poor air quality again with a Spare the Air day.

VIDEO: Extreme heat dangers and safety tips: What you need to know

AccuWeather has tips for making it through a prolonged heat wave.

The heat wave will continue Thursday for a fourth day with advisories and warnings set to expire Thursday night. However, there will likely be an extension or a fresh round of heat warnings and advisories this weekend for hot weather.

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