Climate of NW3
Much like the rest of London, NW3's climate is a function of its proximity to the European continent, its position close to the North Atlantic and North Sea, the Urban Heat Island effect, and London's northerly latitude. With the prevailing wind being broadly south-westerly, bringing tropical maritime air, London has consistent rainfall throughout the year, relatively low sunshine totals, few snow days, and a lack of temperature extremes - those generally coming when the wind switches to the Arctic north or polar north-east (cold), or to the continental south or south-east (heat).
Thunderstorms are infrequent and generally weak compared with those of the near continent. The main weather hazards in NW3 are strong winds, dense fog, and the occasional heat wave or icy cold snap. Although not subject to river flooding (NW3 is home to inner London's highest point, Whitestone Pond, 134 m), brief flash flooding has occurred from localised slow-moving thunderstorms.
Long-term Climate Averages
These are estimates for the long-term average conditions at NW3, derived from data for 1991-2020 - the WMO standard reference period - from nearby official Met Office sites (Heathrow and Northolt), adjusted for local differences.
| Temperature / °C | Rain / mm | Wind Speed / mph |
Days Of | Days Of Snow | Wet Hours |
Sun Hrs (% of max) |
|||||||
| Min | Max | Mean | Range | Rainfall | >1mm Days |
Air Frost | Thun der |
Lying | Falling | ||||
| Jan | 3.0 | 7.8 | 5.4 | 4.8 | 59 | 11 | 5.2 | 6 | 0.4 | 2.5 | 5 | 67 | 69 (30%) |
| Feb | 3.0 | 8.2 | 5.6 | 5.2 | 45 | 9 | 5.1 | 6 | 0.3 | 2.5 | 5 | 52 | 78 (31%) |
| March | 4.3 | 10.9 | 7.6 | 6.6 | 39 | 10 | 5.2 | 3 | 0.6 | 0.4 | 4 | 53 | 113 (34%) |
| April | 6.0 | 14.3 | 10.2 | 8.3 | 42 | 10 | 4.9 | 0.7 | 1 | 0.2 | 2 | 46 | 161 (43%) |
| May | 9.0 | 17.8 | 13.4 | 8.8 | 46 | 9 | 4.7 | 0 | 2 | 0 | 0 | 40 | 189 (43%) |
| June | 12.0 | 20.9 | 16.4 | 8.9 | 47 | 9 | 4.4 | 0 | 3 | 0 | 0 | 37 | 194 (43%) |
| July | 14.2 | 23.0 | 18.6 | 8.8 | 46 | 8 | 4.3 | 0 | 2.5 | 0 | 0 | 34 | 195 (43%) |
| Aug | 14.1 | 22.5 | 18.3 | 8.4 | 54 | 8 | 4.0 | 0 | 2.5 | 0 | 0 | 38 | 185 (45%) |
| Sep | 11.5 | 19.1 | 15.3 | 7.6 | 50 | 9 | 3.9 | 0 | 2 | 0 | 0 | 41 | 147 (43%) |
| Oct | 8.6 | 14.8 | 11.7 | 6.2 | 65 | 11 | 4.1 | 0.3 | 1 | 0 | 0 | 49 | 118 (40%) |
| Nov | 5.5 | 10.7 | 8.1 | 5.2 | 67 | 10 | 4.6 | 2 | 0.4 | 0.3 | 1 | 63 | 84 (35%) |
| Dec | 3.6 | 8.2 | 5.9 | 4.6 | 57 | 11 | 5.1 | 5 | 0.3 | 1 | 3 | 62 | 65 (30%) |
| Winter | 3.2 | 8.1 | 5.6 | 4.9 | 161 | 31 | 5.1 | 17 | 1 | 6 | 13 | 181 | 212 (30%) |
| Spring | 6.4 | 14.3 | 10.4 | 7.9 | 127 | 29 | 4.9 | 3.7 | 3.6 | 0.6 | 6 | 139 | 463 (40%) |
| Summer | 13.4 | 22.1 | 17.8 | 8.7 | 147 | 25 | 4.2 | 0 | 8 | 0 | 0 | 109 | 574 (44%) |
| Autumn | 8.5 | 14.9 | 11.7 | 6.3 | 182 | 30 | 4.2 | 2.3 | 3.4 | 0.3 | 1 | 153 | 349 (40%) |
| Sum | 617 | 115 | 23 | 16 | 6.9 | 20 | 582 | 1598 (40%) | |||||
| Annual | 7.9 | 14.8 | 11.4 | 7.0 | 51 | 9.5833333333333 | 4.6 | 1.9166666666667 | 1.3333333333333 | 0.575 | 1.6666666666667 | 48.5 | 133.16666666667 (40%) |
| Range | 11.2 | 15.2 | 13.2 | 4.3 | 28 | 3 | 1.3 | 6 | 2.7 | 2.5 | 5 | 33 | 130 |
A day-by-day progression of the temperature averages can be found here.