Climate averages 1991–2020

Hagåtña weather
in September.

A hot, very wet month: the joint 4th warmest and the 11th driest of the year.

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

Average high 28.3°C Daytime mean, September

Average low 26.1°C Night-time mean, September

Rainfall 314 mm 27 days with ≥1 mm

Daylight 12 h Sunrise to sunset, per day

September is a hot month in Hagåtña: daytime highs average 28.3°C and nights cool to about 26.1°C. By daytime temperature it is the joint 4th warmest of the 12 months.

Expect about 314 mm of rain on roughly 27 days, which makes September a very wet month (the 11th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 13 min on an average September day.

The nearest other city in this atlas is Saipan (221 km away). In September its highs average 27.1°C, 1.2°C cooler than Hagåtña, with 298 mm of rain.

From September to October, average highs fall by 0.1°C to 28.3°C, and monthly rainfall falls from 314 mm to 279 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

Hagåtña climate table

1991–2020

Monthly climate averages for Hagåtña, 1991–2020
Month	Average highHigh / low	Average low	Rainfall mm/month	Rain days ≥1 mm/day	Daylight hours/dayDaylight h/day
January	27.3°C25.8°C	25.8°C	71	14.7	11.411 h
February	27.1°C25.6°C	25.6°C	52	11.5	11.712 h
March	27.4°C25.7°C	25.7°C	45	10.2	12.012 h
April	27.9°C26.1°C	26.1°C	67	11.1	12.412 h
May	28.4°C26.4°C	26.4°C	81	15.0	12.713 h
June	28.6°C26.5°C	26.5°C	140	20.4	12.913 h
July	28.4°C26.2°C	26.2°C	272	28.4	12.813 h
August	28.3°C26.1°C	26.1°C	350	29.2	12.613 h
September, selected	28.3°C26.1°C	26.1°C	314	27.2	12.212 h
October	28.3°C26.1°C	26.1°C	279	27.5	11.812 h
November	28.3°C26.5°C	26.5°C	175	21.5	11.512 h
December	27.9°C26.3°C	26.3°C	93	16.8	11.311 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 Hagåtña

Saipan in SeptemberNorthern Mariana Islands · 221 kmHigh 27.1°C · Low 24.8°C · 298 mm rain

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