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Mystic climate
Typical historical weather for Mystic, United States, averaged across 10 years of hourly climate data. Pick a date for a specific day.
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Annual average
11.7°C
across all months
Warmest month
28.4°C
Jul average high
Coolest month
-3.6°C
Jan average low
Annual rainfall
1251mm
total per year
Mystic is typically hottest in July and coolest in January, a swing of about 32°C across the year. About 29% of annual rainfall falls in the three wettest months (December is typically wettest, June driest).
Monthly averages
Average daily high/low temperature (band) and monthly rainfall (bars).
| Month | Avg high | Avg low | Rainfall | Wet days | Humidity | Wind | Cloud | Solar |
|---|---|---|---|---|---|---|---|---|
| Jan | 3.8°C · record 10.4–20.4°C | -3.6°C · record -20.2–-3.5°C | 99mm | 10 | 65% | 3.8 m/s | 57% | 2.1 kWh/m² |
| Feb | 5.5°C · record 9.2–19.7°C | -2.6°C · record -23.9–-8.3°C | 91mm | 11 | 66% | 3.7 m/s | 60% | 2.9 kWh/m² |
| Mar | 9.4°C · record 14–21.3°C | 0.7°C · record -14.7–-3°C | 106mm | 11 | 60% | 3.9 m/s | 58% | 4.2 kWh/m² |
| Apr | 14.3°C · record 17.5–32.6°C | 5.3°C · record -5.6–1.2°C | 109mm | 11 | 63% | 3.7 m/s | 63% | 5 kWh/m² |
| May | 19.9°C · record 24.3–33.1°C | 10.5°C · record 1.4–6.8°C | 104mm | 12 | 69% | 3.2 m/s | 65% | 5.8 kWh/m² |
| Jun | 25.2°C · record 29–38°C | 15.6°C · record 6.7–11.7°C | 85mm | 10 | 71% | 3 m/s | 60% | 6.3 kWh/m² |
| Jul | 28.4°C · record 31.6–38.3°C | 19.7°C · record 13.2–16.7°C | 129mm | 12 | 74% | 2.8 m/s | 59% | 6.1 kWh/m² |
| Aug | 27.4°C · record 29.8–34.7°C | 18.6°C · record 10.1–15.3°C | 104mm | 12 | 74% | 2.8 m/s | 58% | 5.5 kWh/m² |
| Sep | 23.6°C · record 27.5–34.5°C | 14.8°C · record 5.4–9.6°C | 101mm | 9 | 76% | 3 m/s | 58% | 4.2 kWh/m² |
| Oct | 18.1°C · record 24.1–30.5°C | 9.3°C · record -3.6–4.8°C | 109mm | 10 | 75% | 3.4 m/s | 53% | 3.1 kWh/m² |
| Nov | 11.6°C · record 18.1–26°C | 2.5°C · record -11.3–-1.4°C | 86mm | 9 | 66% | 3.7 m/s | 47% | 2.3 kWh/m² |
| Dec | 5.9°C · record 13–16.9°C | -1.7°C · record -15–-6.9°C | 129mm | 10 | 68% | 3.6 m/s | 56% | 1.7 kWh/m² |
"Avg high"/"Avg low" is the mean daily high/low for that month, averaged across every year on file. The "record" figure alongside it is a different statistic — the single hottest (or coldest) hour ever recorded during that month across all years — so it can sit above or below the average and does not describe the average's year-to-year spread. A "wet day" is any day with at least 1.0mm of rain.
Year to year
Annual average temperature, 2016–2025.
Across these 10 years, the annual average has moved by about +0.27°C per decade. That’s a short window for a reliable long-term climate trend — treat it as indicative, not definitive.
Annual rainfall has moved by about -127.95mm per decade over the same period.
2025 (the most recent year on file) averaged 11.216258664762615°C, below the 9-year baseline of 11.76°C by 1.56 standard deviations.
Typical extremes per year
Rainy days
127.7 days
≥1.0mm rain
Heavy rain days
15.3 days
≥20mm rain
Extreme heat days
0 days
daily high ≥40°C
Frost days
89 days
daily low ≤0°C
Averaged across 10 years on file. Thresholds match PastClimate's data pipeline definitions — see data & sources.
Records on file
Ranked across 10 years of data currently on file (2016–2025).
Hottest day
38.3°C
28 July 2020
2020 was 0.91 SD above the 9-year average that year
Coldest day
-23.9°C
15 February 2016
2016 was 0.24 SD above the 9-year average that year
Wettest day
105.4mm
11 December 2024
2024 was 0.48 SD above the 9-year average that year
Windiest day
10m/s
2 March 2018
2018 was 0.81 SD below the 9-year average that year
See the detail: Mystic on 11 December 2024.
Nearby cities
Norwich
Same ERA5 grid cell
New London
Same ERA5 grid cell
Ledyard
Same ERA5 grid cell
Groton
Same ERA5 grid cell
Conning Towers-Nautilus Park
Same ERA5 grid cell
Preston City
Same ERA5 grid cell
Want a side-by-side view instead? Compare Mystic with another city.
Frequently asked questions about Mystic's climate
What is the hottest month in Mystic?
July is typically the warmest month in Mystic, with an average high of 28.4°C. January is typically the coolest, averaging -3.6°C overnight.
How much does it rain in Mystic?
Mystic gets about 1251mm of rain a year on average, with roughly 29% of it falling in the three wettest months (December is typically the wettest, June the driest).
How many extremely hot or cold days does Mystic have?
On average, Mystic sees about 0 day(s) a year at or above 40°C and about 89 day(s) at or below 0°C, based on 10 years of data.
Is Mystic getting warmer?
Across the 10 years on file (2016–2025), the annual average temperature has moved by about +0.27°C per decade. That's a short window for a reliable long-term climate trend — treat it as indicative, not definitive.
What is the hottest day on record for Mystic?
The hottest day on file is 28 July 2020 at 38.3°C, out of 10 year(s) searched.
Data & provenance
↓ Download monthly CSVData source & coverage — ERA5 reanalysis, 2016–2025 (10 years)details
- Source
- ERA5 reanalysis, accessed via the Copernicus Climate Change Service (C3S) Climate Data Store
- Data type
- Reanalysis — a physically consistent reconstruction combining a forecast model with historical observations, not a live station reading or a forecast
- Coverage
- 2016–2025 (10 years) for United States
- Location
- Mystic — 41.500°, -72.000°, ERA5 grid cell center, 16.4 km from requested point
- Time zone
- America/New_York
- What's shown here
- Monthly and annual averages, and dated extreme-value records, derived from an hourly base record.
- Spatial resolution
- 0.25° (~25 km) distributed grid — ERA5's native model resolution is finer; this is the publicly distributed regridded product
- Version / refreshed
- Methodology v2026.07 · data last refreshed December 31, 2025
- Limitations
- A model reconstruction, not a station observation — hyper-local extremes (a single storm cell, an urban heat pocket) can differ from a nearby gauge. See the full methodology.
- Attribution
- Generated using Copernicus Climate Change Service information
Cite this data
PastClimate (2026-07-17). Historical climate data for Mystic, United States (41.50°N, 72.00°W), derived from ERA5 (Hersbach et al., 2023, Copernicus Climate Change Service). Retrieved from https://www.pastclimate.com/
PastClimate. (2026). Historical climate data for Mystic, United States [Data set]. Derived from ERA5 (Copernicus Climate Change Service). Retrieved July 17, 2026, from https://www.pastclimate.com/
"Historical Climate Data for Mystic, United States." PastClimate, derived from ERA5 (Copernicus Climate Change Service), July 17, 2026, www.pastclimate.com.
@misc{pastclimate,
author = {PastClimate},
title = {Historical climate data for Mystic, United States},
year = {2026},
note = {Derived from ERA5 (Hersbach et al., 2023), Copernicus Climate Change Service. Accessed 2026-07-17},
url = {https://www.pastclimate.com/}
}Notice something wrong with this data? Report a data issue.