Castle Semple Loch

Lake Freshwater loch used for sailing and wildlife habitats

Loch in Scotland’s Clyde area used for sailing, rowing and watersports, bordered by walking routes and a country park. Visitors launch small craft or follow shoreline paths.

Main image

Castle Semple Loch is a freshwater loch in Renfrewshire, Scotland, lying beside the village of Lochwinnoch and forming the core of a larger country park. It is a well-used recreational resource for sailing, watersports and birdwatching.

The loch has public access points and an adjacent visitor area offering trails, picnic facilities and watersports services. The shoreline includes reedbeds and wetland habitats that are important for wildfowl and migrating birds, and the loch is a regular site for community sailing and outdoor recreation.

Historically the loch takes its name from the Castle Semple estate that occupied the area; the grounds are now managed for public access and nature conservation within a country-park framework. The loch sits in the lowland west-central belt of Scotland, within Renfrewshire and close to the settlement of Lochwinnoch.

  • Birdwatching: The loch and surrounding country park are popular for birdwatching, with reedbeds and shoreline habitats attracting wildfowl and waders.
  • Recreation and facilities: The site supports organised watersports and community sailing activities, with facilities at the park for launching small craft.

What to See #

  • Loch waters: Open water of the loch used for sailing, canoeing and other non-motorised watersports, with several launch points along the shore.
  • Country Park and visitor centre: Adjacent Country Park and visitor facilities offering trails, picnic areas and a watersports centre that supports training and boat hire.
Castle Semple Loch
Castle Semple Loch, Renfrewshire, Scotland
55.7833, -4.6000

How to Get to Castle Semple Loch #

The loch is a short drive from Paisley and Glasgow (roughly 30-40 minutes by car). Regional buses serve nearby towns; on-site parking is available at designated access points.

Tips for Visiting Castle Semple Loch #

  • Bring binoculars-the loch is worth watching for waterfowl and otters in the early morning.
  • There are pleasant walking loops around Lochwinnoch that link with the loch; combine forest paths with lochside views.
  • Check local angling regulations if fishing-the loch is used by local clubs.

Best Time to Visit Castle Semple Loch #

Late spring through summer is best for outdoor activities and the longest daylight hours.

Late spring-summer
May-August · 10-20°C (50-68°F)
Long days for walking and water activities; peak time for sailing clubs.
Autumn
September-October · 6-15°C (43-59°F)
Changing light and quieter paths-good for birdwatching.

Weather & Climate near Castle Semple Loch #

Climate

Castle Semple Loch's climate is classified as Oceanic - Oceanic climate with cool summers (peaking in July) and cold winters (coldest in February). Temperatures range from 1°C to 18°C. Abundant rainfall (1345 mm/year), wettest in January.

Best Time to Visit
JuneJulyAugust
Temperature & Rainfall
Temperature Range
27°
Warmest Month
-8°
Coldest Month
Monthly Conditions

January

January is cold with highs of 6°C and lows of 1°C. The wettest month with heavy rain (153 mm), mostly overcast skies, and breezy conditions.

32 Poor

Comfort

Feels Like Cold
C
Temperature
95%
Humidity
Very Humid

Weather

153 mm
Rainfall
6.0 m/s
Wind
Breezy
0.0
UV Index
Low
7.6h daylight

February

February is the coolest month with highs of 6°C and lows of 1°C. Significant rainfall (106 mm) and mostly overcast skies.

40 Poor

Comfort

Feels Like Cold
C
Temperature
94%
Humidity
Very Humid

Weather

106 mm
Rainfall
5.7 m/s
Wind
Light Breeze
0.1
UV Index
Low
9.4h daylight

March

March is cold with highs of 8°C and lows of 2°C. Significant rainfall (118 mm) and mostly overcast skies.

42 Poor

Comfort

Feels Like Cold
C
Temperature
91%
Humidity
Very Humid

Weather

118 mm
Rainfall
5.6 m/s
Wind
Light Breeze
0.3
UV Index
Low
11.7h daylight

April

April is cold with highs of 10°C and lows of 3°C. Moderate rainfall (70 mm) and mostly overcast skies.

54 Acceptable

Comfort

Feels Like Cold
C
Temperature
11°
87%
Humidity
Very Humid

Weather

70 mm
Rainfall
4.7 m/s
Wind
Light Breeze
0.6
UV Index
Moderate
14.0h daylight

May

May is cold with highs of 14°C and lows of 6°C. Moderate rainfall (71 mm) and mostly overcast skies.

56 Acceptable

Comfort

10°
Feels Like Cold
10°C
Temperature
14°
84%
Humidity
Very Humid

Weather

71 mm
Rainfall
4.5 m/s
Wind
Light Breeze
1.0
UV Index
High
16.0h daylight

June

June is cool with highs of 16°C and lows of 8°C. Moderate rainfall (72 mm) and mostly overcast skies.

62 Good

Comfort

12°
Feels Like Cool
12°C
Temperature
16°
85%
Humidity
Very Humid

Weather

72 mm
Rainfall
4.3 m/s
Wind
Light Breeze
1.2
UV Index
High
17.1h daylight

July

July is cool with highs of 18°C and lows of 10°C. Regular rainfall (83 mm) and mostly overcast skies.

60 Good

Comfort

14°
Feels Like Cool
14°C
Temperature
10° 18°
86%
Humidity
Very Humid

Weather

83 mm
Rainfall
4.0 m/s
Wind
Light Breeze
1.1
UV Index
High
16.6h daylight

August

August is cool with highs of 17°C and lows of 10°C. Significant rainfall (101 mm) and mostly overcast skies.

58 Acceptable

Comfort

14°
Feels Like Cool
14°C
Temperature
10° 17°
88%
Humidity
Very Humid

Weather

101 mm
Rainfall
4.0 m/s
Wind
Light Breeze
0.9
UV Index
Moderate
14.8h daylight

September

September is cool with highs of 15°C and lows of 8°C. Significant rainfall (130 mm) and mostly overcast skies.

50 Acceptable

Comfort

12°
Feels Like Cool
12°C
Temperature
15°
90%
Humidity
Very Humid

Weather

130 mm
Rainfall
4.6 m/s
Wind
Light Breeze
0.5
UV Index
Moderate
12.6h daylight

October

October is cold with highs of 12°C and lows of 6°C. Significant rainfall (150 mm) and mostly overcast skies.

46 Poor

Comfort

Feels Like Cold
C
Temperature
12°
92%
Humidity
Very Humid

Weather

150 mm
Rainfall
4.9 m/s
Wind
Light Breeze
0.2
UV Index
Low
10.3h daylight

November

November is cold with highs of 9°C and lows of 3°C. Significant rainfall (146 mm) and mostly overcast skies.

40 Poor

Comfort

Feels Like Cold
C
Temperature
94%
Humidity
Very Humid

Weather

146 mm
Rainfall
5.2 m/s
Wind
Light Breeze
0.1
UV Index
Low
8.1h daylight

December

December is cold with highs of 7°C and lows of 2°C. Significant rainfall (145 mm) and mostly overcast skies.

36 Poor

Comfort

Feels Like Cold
C
Temperature
95%
Humidity
Very Humid

Weather

145 mm
Rainfall
5.3 m/s
Wind
Light Breeze
0.0
UV Index
Low
6.9h daylight

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