How Hot Will It Be Tomorrow? Reading UK Temperature Forecasts and Feels-Like

"How hot will it be tomorrow?" spikes on our search logs the moment the first warm spell of summer looks likely, and as June 2026 opens it is climbing fast. The honest answer is that the headline number on your phone is only half the story. The temperature a forecast shows you is measured in the shade, two metres off the ground, and it tells you very little about how the day will actually feel in direct sun, in a breeze, or in a humid city street. This guide shows you how to read a UK temperature forecast properly, why "feels-like" often matters more than the real figure, and how far ahead those numbers can be trusted.

The Short Answer

If you only remember three things:

1. The forecast temperature is an air temperature in the shade. Standing in direct June sun can feel 5 to 10C warmer than the number suggests.
2. Feels-like is the figure to plan your day around. It folds in wind and humidity, and in summer it is usually the more useful of the two.
3. For "how hot tomorrow?", same-day and next-day forecasts are reliable to within a degree or two. Beyond 5 days, treat the exact figure as a trend, not a promise.

If you want the reasoning, read on.

What the Temperature Number Actually Measures

When the Met Office temperature guide gives you "24C at 3pm", that reading follows a strict international standard. It is the air temperature measured in the shade, in a ventilated screen, at roughly 1.25 to 2 metres above open grass, away from buildings and tarmac.

That standard exists so that a reading in Aberdeen is comparable to one in Aberystwyth. The catch is that almost nobody spends their afternoon standing in a ventilated screen over open grass.

In practice, on a clear June afternoon:

• Direct sunlight can add the equivalent of 5 to 10C to how warm your skin feels.
• A south-facing patio or pavement radiates stored heat back at you, pushing it higher still.
• A city centre runs warmer than the surrounding countryside, often by 3 to 5C overnight, because of the urban heat island effect.

So a "pleasant 22C" forecast can mean a sweltering walk down a sun-trapped high street, or a chilly wait at an exposed, breezy bus stop. The number is right; it is just answering a narrower question than the one you asked.

Why Feels-Like Usually Matters More

Most modern apps show a second figure, the feels-like or apparent temperature. This is the one I plan my day around in summer, and it is worth understanding why.

Feels-like adjusts the raw air temperature for two things your body actually responds to:

• Wind: moving air strips heat from your skin. A brisk coastal breeze can make 19C feel like 15C.
• Humidity: when the air is already moist, sweat evaporates more slowly, so your body cannot shed heat. On a muggy day, 27C can feel like 31C.

In winter, feels-like is dominated by wind chill. In summer, the driver flips to humidity, which is why a warm, sticky, still day in late July often feels far worse than a hotter but drier and breezier one. The same logic explains the difference between a comfortable 28C in dry inland air and an oppressive 26C in humid southern England.

Real Temperature vs Feels-Like: A Summer Example

When the two figures diverge by 3C or more, trust the feels-like for deciding what to wear and whether to be out in the middle of the day.

When a Warm Spell Becomes a Heatwave

There is an official threshold, and it is not the same everywhere in the UK. The Met Office defines a heatwave as at least three consecutive days where the daily maximum meets or exceeds a county-specific threshold.

That threshold ranges from 25C across much of the north and west to 28C in and around London, reflecting what is unusual for each area rather than a single national number. It is why the headlines can call something a heatwave in Yorkshire while London shrugs at the same temperature.

If a genuine hot spell is forecast, the UK Health Security Agency and Met Office issue heat-health alerts, usually 24 to 48 hours ahead. Those are a better signal that the heat is serious than any single forecast figure, in the same way storm warnings beat a generic rainfall forecast.

How Reliable Is "How Hot Tomorrow?"

Temperature is one of the most predictable parts of a forecast, more so than the exact timing of rain. For the full picture see our guide on how accurate weather forecasts really are, but in brief:

• Today and tomorrow: maximum temperature is usually accurate to within 1 to 2C. Trust it.
• 2 to 3 days: still very good for the daily high, give or take a couple of degrees.
• 4 to 5 days: reliable for the broad trend, warm or cool, less so for the exact peak.
• Beyond 7 days: treat any specific figure as a guide to the pattern, not a plan.

Temperature holds up better than rain timing because it is driven by large, slow-moving air masses rather than small convective showers. If a forecast says 29C in four days, the warmth is likely; whether it peaks at 27C or 31C is the part still in flux.

A Quick Routine for Reading a Summer Forecast

Here is the 60-second check I run before a hot day out:

1. Read the feels-like, not just the air temperature. That is your real planning number.
2. Check the wind. Light wind plus high sun plus humidity is the recipe for an uncomfortable day, even at modest air temperatures.
3. Look at the overnight low. A warm night above 18C means homes and cities do not cool down, which matters for sleep and for anyone vulnerable to heat.
4. Cross-check two sources. I compare the Met Office against BBC Weather; when both agree on a hot day, it is a safe bet.
5. Watch for a heat-health alert. If one is issued, take the heat seriously regardless of the headline number.

For why some summers turn hot and dry while others stay grey and unsettled, our UK weather patterns explained guide covers the air masses and jet stream behind it.

Frequently Asked Questions

What is the difference between temperature and feels-like?

Temperature is the air temperature measured in the shade to an international standard. Feels-like adjusts that figure for wind and humidity to estimate how warm or cold it actually feels on your skin. In summer, humidity tends to push feels-like above the air temperature; a strong breeze pushes it below.

Why does it feel hotter than the forecast says?

The forecast temperature is measured in the shade, away from buildings. In direct summer sun, on hot pavements, or in a humid, still city, it can feel several degrees warmer. Direct sunlight alone can add the equivalent of 5 to 10C to how your skin perceives the heat.

How hot does it have to be for a heatwave in the UK?

The Met Office uses county-specific thresholds of three or more consecutive days at or above a daily maximum that ranges from 25C in much of the north and west to 28C around London. There is no single national number, which is why the same temperature can be a heatwave in one region and not another.

How accurate is the temperature forecast for tomorrow?

Very accurate. Next-day maximum temperatures are typically right to within 1 to 2C, because temperature is driven by large, slow-moving air masses. It is far more reliable than the exact timing of showers at the same range.

Should I trust a 14-day temperature forecast?

Use it for the trend, not the exact figure. A 14-day outlook is useful for spotting whether a warm or cool spell is coming, but the specific daily high two weeks out can easily shift by several degrees as the models update.

The Honest Answer to "How Hot Will It Be Tomorrow?"

Read the feels-like figure, glance at the wind and the overnight low, and trust the next-day number to within a degree or two. The headline temperature is accurate, but it is measured in the shade for a weather station, not for you standing on a sun-baked pavement. Pair the air temperature with feels-like and you will dress for the day you actually get.

And if you just want to know whether to grab a brolly, sun cream, or a jacket for your own town, that is the whole point of doineedabrolly.co.uk: a simple, location-specific answer pulled from Met Office data and updated through the day.