Tonight in Merthyr Tydfil
Great sleeping conditions
You'll sleep well.
Sleep Score
8
⁄10
Comfortable
Overnight low
9°C
Cold — layer up
Stickiness
15°C
Slightly muggy
Cooling by 4am
3.8°C
Moderate cooling
Tonight's plan
Cold overnight — ideal for sleep depth if your bedroom stays above 16°C.
Windows
Open
Cool air tonight — let it in
Heating
Not needed
Cool but comfortably above the 16°C floor — duvet does the work
Bedding
Thick duvet + extra layer
Cold night — your body needs insulation to maintain core temperature
Fan
Not needed
Cool enough without — save the electricity
Based on temperature, dew point, wind, and overnight cooling
Why this matters
9°C is cool — ideal for sleep depth. Research shows deeper slow-wave sleep in cooler bedrooms, as long as the room stays above about 16°C. If your bedroom drops below that, sleep quality starts to decline again.
The week ahead
Sat will be the best night, tonight the worst.
Merthyr Tydfil · next 7 nights
Every night this week looks comfortable.