Connecticut climate by month
January highs across Connecticut range from 36°F in Waterbury to 39°F in Mystic; July highs from 81°F in Mystic to 85°F in Hartford. The most common best months across these cities are May, June, September.
Connecticut weather month by month
Average of the 5 Connecticut cities on this site, computed from NOAA's unrounded values (so it can differ by a degree from averaging the rounded city figures); individual cities differ, sometimes a lot.
| Month | High | Low | Wet days | Snow |
|---|---|---|---|---|
| January | 38°F | 22°F | 11 | 10.0 in |
| February | 40°F | 23°F | 9 | 12.1 in |
| March | 47°F | 30°F | 11 | 8.0 in |
| April | 59°F | 40°F | 11 | 1.3 in |
| May | 69°F | 50°F | 12 | 0.0 in |
| June | 78°F | 59°F | 11 | 0.0 in |
| July | 83°F | 65°F | 10 | 0.0 in |
| August | 82°F | 64°F | 10 | 0.0 in |
| September | 75°F | 57°F | 9 | 0.0 in |
| October | 64°F | 45°F | 10 | 0.2 in |
| November | 53°F | 36°F | 10 | 1.3 in |
| December | 43°F | 28°F | 11 | 7.7 in |
Regional differences
Warmest and coolest Connecticut city each month
| Month | Warmest | Coolest | Best month for |
|---|---|---|---|
| January | Mystic 39°F | Waterbury 36°F | – |
| February | Mystic 41°F | Waterbury 39°F | – |
| March | Hartford 48°F | Waterbury 47°F | – |
| April | Hartford 60°F | Mystic 57°F | – |
| May | Hartford 71°F | Mystic 66°F | 4 cities |
| June | Hartford 80°F | Mystic 75°F | 1 city |
| July | Hartford 85°F | Mystic 81°F | – |
| August | Hartford 83°F | Mystic 80°F | – |
| September | Hartford 76°F | Mystic 74°F | 2 cities |
| October | Bridgeport 64°F | Stamford 63°F | – |
| November | Bridgeport 54°F | Waterbury 52°F | 1 city |
| December | Mystic 44°F | Waterbury 41°F | – |
By normal daily high. "Best month for": how many of the 5 cities have it among their best months by our comfort score.
Frost and humidity across Connecticut
- Earliest typical last frostBridgeport: Apr 5
- Latest typical last frostWaterbury: Apr 26
- Most muggy daysMystic: 45 a year
- Fewest muggy daysWaterbury: 30 a year
All Connecticut cities
| City | Jan high | Jul high | Wet days/yr | Snow/yr | Best months |
|---|---|---|---|---|---|
| Bridgeport | 38°F | 83°F | 125 | 33.6 in | May, Jun, Sep |
| Hartford | 37°F | 85°F | 128 | 51.7 in | May |
| Mystic | 39°F | 81°F | 127 | 24.5 in | Nov |
| Stamford | 37°F | 83°F | 124 | 33.6 in | May |
| Waterbury | 36°F | 84°F | 123 | 59.1 in | May, Sep |
Also covered: New Haven (see Bridgeport). These cities use the same weather stations as the city named.