Climate averages 1991–2020

Rustaq weather
in September.

A very hot, very dry month: the 5th warmest and the 2nd driest of the year.

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

Average high 39.0°C Daytime mean, September

Average low 28.7°C Night-time mean, September

Rainfall 1.7 mm fewer than one day with ≥1 mm

Daylight 12 h Sunrise to sunset, per day

September is a very hot month in Rustaq: daytime highs average 39.0°C and nights cool to about 28.7°C. By daytime temperature it is the 5th warmest of the 12 months.

Expect about 1.7 mm of rain on fewer than one day, which makes September a very dry month (the 2nd driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 18 min on an average September day.

The nearest other city in this atlas is As Suwayq (51 km away). In September its highs average 37.7°C, 1.3°C cooler than Rustaq, with almost no rain (under 1 mm).

Among the 12 cities listed in Oman, Rustaq ranks 3rd of 12 for the warmest September highs and 10th of 12 for the driest September (rainfall, lowest first). The mean September high of those 12 cities is 36.7°C; Rustaq is 2.3°C warmer than that mean.

From September to October, average highs fall by 3.6°C to 35.4°C, and monthly rainfall rises from 1.7 mm to 2.7 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

Rustaq climate table

1991–2020

Monthly climate averages for Rustaq, 1991–2020
Month	Average highHigh / low	Average low	Rainfall mm/month	Rain days ≥1 mm/day	Daylight hours/dayDaylight h/day
January	24.6°C15.6°C	15.6°C	14	2.5	10.911 h
February	27.1°C17.2°C	17.2°C	14	2.2	11.411 h
March	30.7°C20.3°C	20.3°C	20	2.7	12.012 h
April	36.2°C24.9°C	24.9°C	13	1.8	12.713 h
May	40.9°C28.7°C	28.7°C	2.3	0.7	13.313 h
June	42.3°C30.9°C	30.9°C	5.0	0.2	13.514 h
July	41.7°C31.5°C	31.5°C	6.0	0.4	13.413 h
August	40.8°C30.6°C	30.6°C	1.0	0.3	12.913 h
September, selected	39.0°C28.7°C	28.7°C	1.7	0.3	12.312 h
October	35.4°C25.3°C	25.3°C	2.7	0.7	11.612 h
November	29.8°C20.9°C	20.9°C	11	1.3	11.011 h
December	26.0°C17.5°C	17.5°C	14	2.2	10.711 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 Rustaq

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