Weather World
Holtsville Monthly Climate Averages
January |
February |
March |
April |
May |
June |
July |
August |
September |
October |
November |
December |
| Hi 39°F Lo 30°F | Hi 40°F Lo 30°F | Hi 46°F Lo 36°F | Hi 54°F Lo 45°F | Hi 63°F Lo 54°F | Hi 72°F Lo 64°F | Hi 80°F Lo 72°F | Hi 79°F Lo 71°F | Hi 73°F Lo 65°F | Hi 64°F Lo 56°F | Hi 53°F Lo 44°F | Hi 45°F Lo 36°F |
| 13 mph | 12 mph | 12 mph | 11 mph | 10 mph | 9 mph | 9 mph | 9 mph | 10 mph | 12 mph | 12 mph | 13 mph |
| 4.3 in | 5 in | 5.4 in | 5 in | 4.8 in | 4.7 in | 5.4 in | 4.8 in | 4.5 in | 5.8 in | 4.3 in | 6.9 in |
| 71% | 73% | 71% | 72% | 77% | 76% | 76% | 73% | 73% | 71% | 69% | 73% |
| 45% | 48% | 46% | 45% | 43% | 37% | 34% | 33% | 36% | 41% | 37% | 48% |
| 30.0 in | 30.0 in | 30.0 in | 30.0 in | 30.0 in | 29.9 in | 30.0 in | 30.0 in | 30.0 in | 30.0 in | 30.1 in | 30.1 in |
| 22 | 19 | 23 | 23 | 24 | 23 | 24 | 24 | 24 | 24 | 24 | 23 |
| 7 | 7 | 7 | 6 | 7 | 7 | 7 | 7 | 6 | 7 | 6 | 7 |
| 3 | 3 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 |
| 0 | 1 | 1 | 0 | 1 | 1 | 0 | 0 | 0 | 1 | 0 | 1 |
| 1 | 2 | 2 | 3 | 5 | 6 | 6 | 6 | 4 | 4 | 2 | 2 |
| 180 | 152 | 176 | 171 | 198 | 217 | 243 | 240 | 216 | 188 | 201 | 165 |
January |
February |
March |
April |
May |
June |
July |
August |
September |
October |
November |
December |
| Hi 4°C Lo -1°C | Hi 4°C Lo -1°C | Hi 8°C Lo 2°C | Hi 12°C Lo 7°C | Hi 17°C Lo 12°C | Hi 22°C Lo 18°C | Hi 27°C Lo 22°C | Hi 26°C Lo 22°C | Hi 23°C Lo 18°C | Hi 18°C Lo 13°C | Hi 12°C Lo 7°C | Hi 7°C Lo 3°C |
| 20 km/h | 20 km/h | 20 km/h | 18 km/h | 16 km/h | 15 km/h | 14 km/h | 14 km/h | 16 km/h | 19 km/h | 20 km/h | 20 km/h |
| 109 mm | 128 mm | 137 mm | 127 mm | 123 mm | 119 mm | 137 mm | 122 mm | 115 mm | 148 mm | 110 mm | 175 mm |
| 71% | 73% | 71% | 72% | 77% | 76% | 76% | 73% | 73% | 71% | 69% | 73% |
| 45% | 48% | 46% | 45% | 43% | 37% | 34% | 33% | 36% | 41% | 37% | 48% |
| 1017 mb | 1017 mb | 1017 mb | 1015 mb | 1016 mb | 1014 mb | 1014 mb | 1016 mb | 1018 mb | 1017 mb | 1019 mb | 1018 mb |
| 22 | 19 | 23 | 23 | 24 | 23 | 24 | 24 | 24 | 24 | 24 | 23 |
| 7 | 7 | 7 | 6 | 7 | 7 | 7 | 7 | 6 | 7 | 6 | 7 |
| 3 | 3 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 |
| 0 | 1 | 1 | 0 | 1 | 1 | 0 | 0 | 0 | 1 | 0 | 1 |
| 1 | 2 | 2 | 3 | 5 | 6 | 6 | 6 | 4 | 4 | 2 | 2 |
| 180 | 152 | 176 | 171 | 198 | 217 | 243 | 240 | 216 | 188 | 201 | 165 |
| Month |
| Avg. Temperatures |
| Avg. Wind Speed |
| Avg. Precipitation |
| Average Humidity |
| Avg. Cloud Cover |
| Pressure Average |
| Average Dry Days |
| Avg. Precip. Days |
| Avg. Snow Days |
| Average Fog Days |
| Average UV Index |
| Avg. Hours of Sun |
Averages are based on historical weather data from the past 10 years.