Climate averages 1991–2020

Santa Barbara weather
in September.

A hot, very dry month: the 3rd warmest and the 3rd driest of the year.

Long-term climate patterns, not a forecast for a particular trip.

Average high 29.6°C Daytime mean, September
Average low 18.8°C Night-time mean, September
Rainfall 2.3 mm fewer than one day with ≥1 mm
Daylight 12 h Sunrise to sunset, per day
Every month in Santa Barbara · average highYear overview

September is a hot month in Santa Barbara: daytime highs average 29.6°C and nights cool to about 18.8°C. By daytime temperature it is the 3rd warmest of the 12 months.

Expect about 2.3 mm of rain on fewer than one day, which makes September a very dry month (the 3rd driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 25 min on an average September day.

The nearest other city in this atlas is Ventura (40 km away). In September its highs average 25.9°C, 3.6°C cooler than Santa Barbara, with 3.1 mm of rain.

Among the 498 cities listed in the United States, Santa Barbara ranks joint 145th of 498 for the warmest September highs and joint 33rd of 498 for the driest September (rainfall, lowest first). The mean September high of those 498 cities is 26.9°C; Santa Barbara is 2.7°C warmer than that mean.

From September to October, average highs fall by 3.2°C to 26.4°C, and monthly rainfall rises from 2.3 mm to 18 mm.

The annual picture

September in context

30-year average
Average highAverage low°C
Average daily high and low temperatures by month The same values are available in the monthly table below. Lines show mean daily maxima and minima, not a forecast interval. 5101520253035 JanFebMarAprMayJunJulAugSepOctNovDec

Monthly rainfall

Average total · mm
Average monthly rainfall totalsEach bar is a mean monthly total over 1991–2020. Full numbers are in the table. JanFebMarAprMayJunJulAugSepOctNovDec 1000

Averages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated

Every month, side by side

Santa Barbara climate table

1991–2020
Monthly climate averages for Santa Barbara, 1991–2020
MonthAverage highHigh / lowAverage lowRainfall mm/monthRain days ≥1 mm/dayDaylight hours/dayDay­light h/day
January 19.1°C9.2°C9.2°C936.210.110 h
February 19.0°C9.3°C9.3°C946.710.911 h
March 20.6°C10.3°C10.3°C705.811.912 h
April 22.7°C11.8°C11.8°C243.013.013 h
May 25.1°C14.3°C14.3°C101.813.914 h
June 27.9°C17.0°C17.0°C2.00.514.414 h
July 30.0°C19.9°C19.9°C2.70.714.214 h
August 30.7°C20.4°C20.4°C0.80.213.413 h
September, selected 29.6°C18.8°C18.8°C2.30.512.412 h
October 26.4°C15.5°C15.5°C181.911.311 h
November 22.4°C11.9°C11.9°C263.010.410 h
December 18.9°C9.1°C9.1°C615.19.910 h

Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.

Compare places

September in nearby cities

Distance from Santa Barbara

Read the numbers correctly

Climate, not a promise.

These patterns help compare months. They cannot tell you the weather on a specific day of your trip.

Sources, method and limits

How these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Santa Barbara) is explained once on the Santa Barbara year overview and on the Sources, method and limits page.