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Weather extremes

How extreme does St. Thomas's weather get?

The hottest, coldest, wettest and snowiest days St. Thomas has recorded — the outer limits of what its weather can do, and how far they sit beyond a normal day.

Based on 21 years of daily weather observations (2004–present), from the London Cs Ont station 29 km away. Updated through August 2025 — an all-time extreme only changes when a more extreme day actually occurs, so some dates are old. That is normal, not stale data.

The four kinds of extreme

The hottest, coldest, wettest and snowiest single days St. Thomas has recorded — each shown against what a normal day that time of year looks like.

🔥 Hottest day
98°F Jul 22, 2011

The three most extreme on record

1 98°F Jul 22, 2011
2 97°F Jul 18, 2012
3 97°F Jul 21, 2011
❄️ Coldest night
-19°F Feb 16, 2015

The three most extreme on record

1 -19°F Feb 16, 2015
2 -17°F Feb 17, 2014
3 -17°F Jan 28, 2005
🌧️ Most rain in one day
3.79 in Sep 21, 2013

The three most extreme on record

1 3.79 in Sep 21, 2013
2 2.76 in Jan 30, 2019
3 2.71 in Sep 11, 2014

In plain terms

Across the record, St. Thomas has reached as high as 98°F and as low as −19°F. A single day has delivered over 4 inches of rain. Those are the outer edges worth knowing if you are moving here, planning a trip, or thinking about a house.
Methodology & sources

Temperature & precipitation — 1991–2020 normals computed from 26 years of daily observations at ST Thomas Wpcp, a weather station, about 2 km from the city centre. The underlying daily records come from NOAA's global station network.

How we build these numbers →