August Just Set a Global Heat and Humidity Record-and It Wasn't Close

Key Points:

• August 2026 was the warmest and most humid August on record globally, with temperatures 2.97°F (1.65°C) above pre-industrial levels and unprecedented atmospheric moisture, according to climatologists Zeke Hausfather and Ben Noll.
• The global precipitable water level reached 1.08 inches (2.74 cm), the highest ever recorded, contributing to extreme weather events including a heat dome in the U.S. and deadly flash floods in the Grand Canyon.
• Rising global temperatures increase atmospheric water vapor, intensifying precipitation extremes through the "expanding atmospheric sponge" effect, where the atmosphere holds 7% more moisture per degree Celsius of warming.
• The strong El Niño event, projected to peak in December with sea surface temperatures 7.2°F (4°C) above average, is amplifying global warming and moisture levels, raising the likelihood that 2026 will be the warmest year on record.
• Increased atmospheric moisture is expected to cause unusually stormy and wet conditions across many regions, including the U.S., Europe, eastern Asia, and South America, heightening risks of extreme rainfall and flooding in the near future.