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Jamestown has a hot semi-arid climate.
Dry country, big sun, modest rain — here's what that means in plain terms.
What this climate feels like
The four things a regular visitor actually wants to know:
Highs near 75°F in March.
Lows near 58°F in August.
About 17 in of rain a year. Wettest in June.
Cloudy skies much of the year.
What "hot semi-arid" means
Climate scientists sort every place on Earth into about 30 climate types, based on how hot, cold, wet and dry it is across the year. Jamestown's type — hot semi-arid — sits in the broad family of dry climates — deserts and steppes.
Researchers write climate types as a short letter code. Here is what each letter means:
Cities with the same climate as Jamestown
A hot semi-arid climate (BSh) — these recognizable cities share it. If you know one of them, you know roughly what to expect.
Jamestown sits near a climate boundary
This city's climate sits within about 2 °C of the next type along. A slightly cooler or warmer decade could change which side of the boundary it lands on — but the lived weather doesn't change at the line.
Has Jamestown's climate type changed?
Stable — Jamestown's climate has held the same type between the 1971–2000 and 1991–2020 normals. The label is steady; the climate beneath it is still warming.
What this climate means for you
Native grasses, drought-tolerant shrubs and hardy fruit trees (figs, pomegranate, olives) do well. Vegetable gardens need irrigation.
Cool half of the year is comfortable; summer is hot and dusty. Watch for wet-season storms during the short rainy stretch.
Hot, dry and dusty — drought is a recurring issue. Comfortable winters; tough, sun-blasted summers.
Where these numbers come from
The climate type and the month-by-month figures on this page are computed from Jamestown's measured 30-year climate normals (1991–2020) — the same official records behind Jamestown's main climate page, so the two always agree.
Long-range climate maps measure things slightly differently and can place a city in a neighbouring category. Where they differ, this page uses the measured station record as the climate today.
Methodology & sources
Temperature & precipitation — 1991–2020 normals computed from 30 years of daily observations at St. Helena Is., a weather station, about 6 km from the city centre. The underlying daily records come from NOAA's global station network.