Rounded, Reading is located at 51° north, 1° west. This puts it above the equator a generous distance, but below the polar section of the world. Overall, this city gets just a hint of chilliness from being closer to the Pole than the equator. Specifically, it is in the Temperate Climate Zone.
The temperature of Reading usually ranges around 2-6 degrees Celsius, generating a slightly colder climate than hangs around freezing, at least during the colder part of the year. Because of this, Reading pertains a slightly cooler climate, though not an uncomfortable one, with a bit of humidity. That could chain to several other things: snow, rain, and other types of precipitation.
Taking in the fact that there isn't much heat to evaporate water, Reading is an almost constantly overcast place, with only about 10 days that aren't cloudy and raining. The average amount (in mm) of rain that Reading receives in the colder months of the year averages out to about 60. This points to a more drab, overcast climate.
For the most part, Reading is an almost-flat plains with small hills bumping along its surface. For this reason, the climate of the city should be widely unaffected by anything land-wise; there are no mountains in that area of the UK to block the wind or weather.
Reading has an elevation of 200 ft (61 meters). Combined with its flat topography, it is plenty easy for wind to sweep right over it, pushing plenty of clouds over the land as well. As it is not that high above sea level, it isn't extremely cold like Mt. Kilimanjaro; rather, it has a slightly warmer temperature because of this, though it retains a bit of coolness.
LARGE BODIES OF WATER
To the Northeast and Southwest of Reading are several bodies of water. As water helps moderate the temperature of nearby land, this adds to the balanced climate of slightly uncomfortable humid and overcast weather of this city.
As there aren't really any oceans or seas near Reading, this factor doesn't really affect it much, if at all. If anything, it might bring a bit of Polar temperature, but that would be unlikely.