Climate averages 1991–2020

Riyadh weather
in September.

A very hot, very dry month: the 4th warmest and one of the driest of the year.

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

Average high 39.4°C Daytime mean, September

Average low 24.2°C Night-time mean, September

Rainfall <1 mm Almost no rain

Daylight 12 h Sunrise to sunset, per day

September is a very hot month in Riyadh: daytime highs average 39.4°C and nights cool to about 24.2°C. By daytime temperature it is the 4th warmest of the 12 months.

Rain is very rare: less than 1 mm falls in a typical September (one of the driest months of the year). Daylight, from sunrise to sunset, lasts about 12 h 19 min on an average September day.

The nearest other city in this atlas is Al Kharj (86 km away). In September its highs average 40.5°C, 1.0°C warmer than Riyadh, with almost no rain (under 1 mm).

Among the 35 cities listed in Saudi Arabia, Riyadh ranks joint 6th of 35 for the warmest September highs and joint 1st of 35 for the driest September (rainfall, lowest first). The mean September high of those 35 cities is 36.0°C; Riyadh is 3.4°C warmer than that mean.

From September to October, average highs fall by 5.5°C to 33.9°C, and monthly rainfall stays under 1 mm.

The annual picture

September in context

30-year average

Average highAverage low°C

Monthly rainfall

Average total · mm

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

Every month, side by side

Riyadh climate table

1991–2020

Monthly climate averages for Riyadh, 1991–2020
Month	Average highHigh / low	Average low	Rainfall mm/month	Rain days ≥1 mm/day	Daylight hours/dayDaylight h/day
January	19.8°C7.4°C	7.4°C	11	2.0	10.811 h
February	23.1°C9.6°C	9.6°C	5.4	1.5	11.311 h
March	27.3°C13.7°C	13.7°C	11	1.9	12.012 h
April	33.1°C19.0°C	19.0°C	14	2.7	12.713 h
May	38.6°C24.1°C	24.1°C	1.9	0.6	13.313 h
June	41.6°C26.0°C	26.0°C	0	0.0	13.614 h
July	42.6°C27.3°C	27.3°C	0	0.0	13.514 h
August	42.5°C27.2°C	27.2°C	0	0.0	13.013 h
September, selected	39.4°C24.2°C	24.2°C	0	0.0	12.312 h
October	33.9°C19.8°C	19.8°C	0.9	0.2	11.612 h
November	26.3°C13.9°C	13.9°C	11	2.1	11.011 h
December	21.3°C8.9°C	8.9°C	9.1	1.7	10.611 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 Riyadh

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 Riyadh) is explained once on the Riyadh year overview and on the Sources, method and limits page.