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Just What Season Is It Anyway?

Many people consider Labor Day as the last weekend of the summer, signaling the end of hot weather and the beginning of the school year. Climatologists define their seasons to be three months long, so that autumn starts on September 1 and ends on November 30, summer starts on June 1st and ends on August 31st, etc. The astronomical first day of autumn starts at the precise moment of the autumnal equinox, which in the Northern Hemisphere can either occur on September 22nd or 23rd. Likewise, the first day of summer starts at the summer solstice (June 20 or 21).

While one might expect the summer solstice to be the hottest day of the year, that day usually occurs in July or August. This lag in our climate from an astronomical standpoint has to do with the high heat capacity of the oceans. The ocean takes a long time to heat up and cool down as compared with the atmosphere. Right now, the ocean is acting as a heat source, fighting against the colder weather that we would otherwise have with the shorter days and lower angle of the sun above the horizon.

Dry, pleasant weather continues through today and tomorrow. Weather forecast models have cooler temperatures and rain for the end of the work week, but the exact time and amount for rain remain uncertain.

Extended Forecast

Today: Mostly sunny. High 77°F (25°C).

Tonight: Partly cloudy. Low 61°F (16°C).

Tomorrow: Partly sunny. High 70°F (21°C).

Thursday: Cloudy with a chance of rain. High 64°F (18°C).

Friday: Cloudy with a chance of rain. High 62°F (17°C).