Groton weather in August: Groton, Connecticut: normal highs, lows, rain and records for August
Groton in August has a normal high of 79°F and a normal low of 64°F, a daily mean of 72°F, falling from 80°F on the 1st to 78°F by the 31st. Measurable precipitation falls on 10 days in a normal August, 3.32 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 26°C and low of 18°C, 84 mm of precipitation in August.
- NOAA stationGroton New London Airport
- Station IDUSW00014707
- Location41.33°N 72.05°W
- Elevation10 ft (3 m)
- Population10,160
- Jan 38° 23°
- Feb 40° 25°
- Mar 47° 31°
- Apr 56° 39°
- May 65° 49°
- Jun 74° 58°
- Jul 80° 65°
- Aug 79° 64°
- Sep 74° 57°
- Oct 63° 46°
- Nov 53° 37°
- Dec 44° 29°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is Groton in August?
The normal high is 79°F and the normal low 64°F, for a daily mean of 71.5°F. August is 0.8°F cooler than July and 6.3°F warmer than September. August is the 2nd warmest month of the year in Groton and the 5th wettest. Across the month the normal high falls 2°F, from 80°F on August 1 to 78°F on August 31. From one year to the next August's mean temperature typically moves about 1.9°F either way (NOAA's standard deviation), so roughly two Augusts in three average between 70°F and 73°F.
Bars above: each day's normal high to low. Columns below: the chance of 0.01 inch or more of precipitation that day, on a scale of 0 to 100% (highest 33%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| August 1 | 80°F | 65°F | 33% | 16% |
| August 8 | 80°F | 65°F | 32% | 17% |
| August 15 | 79°F | 64°F | 32% | 16% |
| August 22 | 79°F | 63°F | 30% | 16% |
| August 31 | 78°F | 62°F | 29% | 15% |
Every day of August: normal high, low and chance of precipitation (warmest afternoon August 1, coldest night August 31)
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in | Daylight |
|---|---|---|---|---|---|
| August 1 | 80°F | 65°F | 33% | 16% | 14 h 20 min |
| August 2 | 80°F | 65°F | 33% | 16% | 14 h 20 min |
| August 3 | 80°F | 65°F | 33% | 16% | 14 h 20 min |
| August 4 | 80°F | 65°F | 33% | 16% | 14 h 20 min |
| August 5 | 80°F | 65°F | 33% | 16% | 14 h 20 min |
| August 6 | 80°F | 65°F | 33% | 17% | 14 h 10 min |
| August 7 | 80°F | 65°F | 33% | 17% | 14 h 10 min |
| August 8 | 80°F | 65°F | 32% | 17% | 14 h 10 min |
| August 9 | 80°F | 65°F | 32% | 17% | 14 h 10 min |
| August 10 | 80°F | 65°F | 32% | 17% | 14 h |
| August 11 | 80°F | 65°F | 32% | 17% | 14 h |
| August 12 | 80°F | 65°F | 32% | 17% | 14 h |
| August 13 | 80°F | 64°F | 32% | 17% | 14 h |
| August 14 | 80°F | 64°F | 32% | 16% | 14 h |
| August 15 | 79°F | 64°F | 32% | 16% | 13 h 50 min |
| August 16 | 79°F | 64°F | 31% | 16% | 13 h 50 min |
| August 17 | 79°F | 64°F | 31% | 16% | 13 h 50 min |
| August 18 | 79°F | 64°F | 31% | 16% | 13 h 50 min |
| August 19 | 79°F | 64°F | 31% | 16% | 13 h 40 min |
| August 20 | 79°F | 63°F | 30% | 16% | 13 h 40 min |
| August 21 | 79°F | 63°F | 30% | 16% | 13 h 40 min |
| August 22 | 79°F | 63°F | 30% | 16% | 13 h 40 min |
| August 23 | 79°F | 63°F | 30% | 15% | 13 h 30 min |
| August 24 | 79°F | 63°F | 30% | 15% | 13 h 30 min |
| August 25 | 79°F | 63°F | 30% | 15% | 13 h 30 min |
| August 26 | 78°F | 63°F | 29% | 15% | 13 h 30 min |
| August 27 | 78°F | 62°F | 29% | 15% | 13 h 20 min |
| August 28 | 78°F | 62°F | 29% | 15% | 13 h 20 min |
| August 29 | 78°F | 62°F | 29% | 15% | 13 h 20 min |
| August 30 | 78°F | 62°F | 29% | 15% | 13 h 20 min |
| August 31 | 78°F | 62°F | 29% | 15% | 13 h 10 min |
- Normal high
- 79°FAugust average
- Normal low
- 64°FAugust average
- Precipitation
- 3.32 inmonth total
- Days with precipitation
- 100.01 inch or more
- Days at 90°F or more
- 1
- Daylight
- 14 h 20 min to 13 h 10 minAugust 1 to August 31
- Days at 70°F or more
- 31
- Days at 80°F or more
- 14
- Sunshine
- 79%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USW00014707; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain in Groton in August?
On a given August day the chance of 0.01 inch or more is 31% on average, highest around August 1 (33%). In all, 3.32 in falls on 10 days of a normal August, 1 of them with an inch or more.
In a normal August in Groton, 1 days reach 90°F.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USW00014707.
What are the records for August in Groton?
The warmest August temperature on this station's record (since 1999) is 93°F, on August 14, 2016; the coldest is 47°F, on August 21, 2000. The wettest August brought 6.80 in (2006).
The August mean against the 1991-2020 normal of 71.5°F: 2021 73.0°F (+1.5), 2022 76.0°F (+4.5), 2023 72.1°F (+0.6), 2026 71.5°F (at normal). 3 of 4 ran warmer than normal.
| August | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 73.0°F | +1.5°F | 1.15 in |
| 2022 | 76.0°F | +4.5°F | 2.55 in |
| 2023 | 72.1°F | +0.6°F | 3.12 in |
| 2026 | 71.5°F | at normal | 4.88 in |
Source: records: ACIS, station USW00014707; recent months: ACIS, station USW00014707. Records and recent months use complete months only.
How does August in Groton compare across Connecticut?
Across the 13 places PlainClimate covers in Connecticut, August normal highs run from 76°F in Norfolk to 83°F in Hartford; Groton's is 79°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.