Seal Beach (CA) Temperature by Month
The average annual maximum temperature in Seal Beach, California, United States of America is 22°C (72°F), with daytime highs ranging from 19°C (66°F) in December to 26°C (79°F) in September. This page covers monthly averages, day-night differences, and how Seal Beach compares to cities worldwide.
Seal Beach Monthly Temperatures
The weather in Seal Beach changes moderately throughout the year, offering enough variation to appreciate each season. Nights are cooler, with lows ranging from 18°C (64°F) to 8°C (46°F).
The chart below illustrates the average maximum day and minimum night temperatures in Seal Beach by month:
Low temperatures are most often recorded between 4 AM and 6 AM, while highs typically occur around 3 PM. September, the city's warmest month, sees 278 hours of sunshine.
The chart below shows the average temperature throughout the year:
Temperature: Seal Beach vs the United States of America
The map below shows the annual temperature across the United States of America. You can also select individual months if you want to compare a specific time of year.
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Seal Beach vs World: Temperature Compared
Seal Beach's average annual maximum temperature is 22°C (72°F). To put that in context, here's how it compares to a few well-known destinations:
Barcelona, Spain has an annual average of around 21°C (70°F), with warm summers and mild, fairly short winters.
Zermatt, Switzerland averages just 4°C (39°F) annually due to its altitude, with very cold winters and cool summers even at its warmest.
Shanghai, China averages 21°C (70°F) a year, with warm summers, mild winters, and a noticeable spring and autumn.
Tokyo, Japan averages 21°C (70°F) a year, with hot summers, cool winters, and a well-defined cherry blossom spring.
What Does the Temperature Feel Like in Seal Beach?
Temperature alone doesn't tell the whole story — humidity plays a big role in how warm or cold it actually feels. High humidity in summer makes the heat feel more intense, particularly once temperatures climb above 25°C. In winter, the same humidity can make cold air feel sharper than the thermometer suggests.
In Seal Beach, December is the coolest month, with average highs of 19°C (66°F) and humidity around 52% — considered moderate. In September, the warmest month, temperatures average 26°C (79°F) with 67% humidity — conditions that feel high. For a full picture, see our humidity page.
Climate temperature data is typically calculated as a 30-year average. This smooths out year-to-year variability and gives a more reliable picture of what a place is actually like, rather than what happened in any single unusual year.
The readings come from a range of sources — land-based weather stations, ocean buoys, ships, and satellites. That data is collected by weather services around the world, then pooled, quality-checked, and averaged to produce the climate records you see here.
Whether a city sits on the coast or deep inland makes a significant difference to its climate. Coastal areas tend to have more stable temperatures year-round — large bodies of water absorb heat slowly in summer and release it gradually in winter, keeping extremes in check. Cities far from the sea don't benefit from that buffer, which is why continental climates tend to have hotter summers and colder winters than their coastal counterparts at the same latitude.
For more on Seal Beach's weather — including monthly rainfall, sunshine hours, and humidity — visit our Seal Beach climate page.
