Happy Morning!
"Mild air, grey skies, and the occasional threat of drizzle — London in spring is never quite predictable, but today offers one of its more generous offerings."
Sky Overcast Mostly cloudy all day
Morning Low 12°C Feels cool outside
Wind Moderate Breezy at times
Rain Risk 20% Carry an umbrella
What to Expect Today in London
Thursday, 21 May 2026 is shaping up to be a typically British spring day — cool and overcast, with a thick layer of cloud holding firm across the city. Londoners woke to a temperature of around 12°C (54°F), but as the day progresses the mercury is expected to climb to a pleasant 23°C (73°F), making it one of the warmer days of the week.
The cloud cover is expected to persist throughout the morning and much of the afternoon, keeping direct sunshine at bay. However, there is a 20% chance of light rain — low enough to go about your day normally, but just enough to warrant tucking a compact umbrella into your bag. Wind conditions are moderate, so open coats and lightweight layers are the order of the day.
How Temperatures Will Move Through the Day
The morning hours (6am–9am) will feel noticeably cool at around 12–14°C, so a light jacket or a mid-layer is strongly advisable for commuters. By midday, temperatures should rise to approximately 18–20°C, offering a comfortable feel if the clouds thin out even briefly. The peak of 23°C is expected in the early afternoon, making it the warmest point of the day before a gentle dip through the evening back to around 15–17°C.
For context, the UK average for May is typically 17–18°C, so today's high is slightly warmer than normal — a welcome sign as the city heads towards summer. If you are planning outdoor activities, the early afternoon window (12pm–3pm) will be your best bet for warmth.
Precautions Before You Head Out
While today is not a severe weather day, a few simple steps will keep you comfortable and prepared throughout the day.
Layer Up for the Morning
At 12°C, early mornings can feel cool, especially in the wind. A light jacket, cardigan, or mid-layer over a t-shirt is ideal. You can always remove a layer as temperatures climb later in the day.
Pack a Compact Umbrella
With a 20% chance of rain, it won't definitely rain — but London's weather is famously changeable. Carrying a small foldable umbrella in your bag costs nothing and keeps you dry if a brief shower develops, particularly in the late afternoon.
Apply Sun Protection if Outdoors
Even on cloudy days, UV rays penetrate cloud cover — particularly as we move into late May. If you plan to spend extended time outdoors (parks, sports, cycling), apply a light SPF to exposed skin.
Stay Hydrated
As afternoon temperatures approach 23°C, it is easy to underestimate how much water your body needs, especially during physical activity. Carry a water bottle and drink regularly throughout the day.
Allow Extra Time for Commuting
Wet roads — even from light drizzle — can slow road traffic and increase braking distances. If you are driving, allow a little extra time and ensure your windscreen wipers are in good condition.
Pet Owners: Watch Paw Temperature
If you have dogs, morning walks on damp pavements are generally comfortable for your pet today. However, if temperatures spike and you walk in the early afternoon, check that pavements haven't heated up significantly before headingout.
Today in a Nutshell
Today is a quintessential spring day in London — cool to start, pleasantly mild by afternoon, and with just enough cloud to keep things interesting. It is not a day to stay indoors. With temperatures peaking at 23°C, a light jacket, a folded umbrella, and a bottle of water are all you really need.
Check back with WeatherLondon.uk throughout the day for updates, and keep an eye on our weekend forecasts as the city prepares for what could be a memorably warm end to May.
