Castlereagh Weather in January

Castlereagh in January sees low daytime temperatures of 9°C (48°F) and nighttime lows of 4°C (39°F). Rainfall is fairly high this month at around 91 mm (3.6 in), so pack a rain jacket to stay dry.

Rainfall in Castlereagh in January

Past climate data indicates that roughly 20 days will see rain, totalling around 91 mm (3.6 in) for the month. This is a month with many wet days but modest rainfall totals, so showers are generally light and easy to manage.

Temperature in Castlereagh in January

January in Castlereagh sees highs of 9°C (48°F) and lows of 4°C (39°F) overnight. During January, the winter season is in full swing. Cold conditions persist throughout the day, so warm clothing is important from the moment you head outside. At 4°C (39°F) overnight, it gets properly cold after dark. On the bright side, cold nights tend to make for excellent sleeping conditions. The temperatures in January are often the mildest compared to the rest of the year.

Sunshine in Castlereagh in January

The city usually sees around 45 hours of sunlight, indicating fewer sunny days.

Wind Speed in Castlereagh in January

Wind speeds average 5 m/s (10 knots) during January. At this speed, gentle to moderate breezes make small trees sway and the wind creates whitecaps on water bodies. Daily variations range from moderate winds to stronger breezes, creating excellent conditions for sailing, kite flying and wind sports.

Average water temperature in January

The water sits at 8°C (46°F) this month, which is well below what most people consider swimmable. Wetsuits help, but expect it to still feel cold.

If you prefer dry days with pleasant temperatures, January may not be the ideal month to visit Castlereagh. Our weather planner can help you explore destinations with more pleasant weather conditions.

Select a Month

Check the conditions for any month of the year.

• January
• February
• March
• April

• May
• June
• July
• August

• September
• October
• November
• December

For a detailed overview over the year and the best time to visit the United Kingdom, check out our Castlereagh's climate page.

Castlereagh Temperature in January

Min Temperature 4°C (39°F)  

Max Temperature 9°C (48°F)  

Water Temperature 8°C (46°F) *  

Chance of Rain 66%  

Precipitation 91 mm (3.6 in)  

Rainy days 20 days  

Humidity 89% *  

Windspeed 5 m/s (10 knots) *  

Sunshine 45 hours *  

Percentage Sunshine 18% *  

* Data from: Belfast, Ireland (24 KM, 15 Miles).

What to Wear in Castlereagh in January

We recommend to layer up for chilly conditions in Castlereagh in January. You could start with thermal underwear or a good base layer to keep your core warm on the cooler days this month. Maybe also add a sweater or fleece, and top it off with a windproof jacket. High rain levels are expected, so pack waterproof gear and an umbrella or poncho. With water temperatures around 8°C (46°F), the water is quite cold for swimming. You can skip the swimwear unless you're particularly tough. Sunglasses aren't essential this month, though you might want them for the occasional bright moment.

What To Do in Castlereagh in January

We rated the following activities from 1 (least suitable) to 10 (best) to do.

Swimming

4/10

Cycling

4/10

Walking

4/10

Camping

4/10

Outdoor sports

4/10

Select a Month

Check the conditions for any month of the year.

• January
• February
• March
• April

• May
• June
• July
• August

• September
• October
• November
• December

For a detailed overview over the year and the best time to visit the United Kingdom, check out our Castlereagh's climate page.

More climate data for Castlereagh

Temperature Rainfall Sunshine Humidity Wind Speed Water Temp

See the full Castlereagh climate overview or explore weather in the United Kingdom.