How GoodDayTo scores your day

The short version

GoodDayTo combines real forecast data with activity-specific rules. A good day for drying laundry is not automatically a good day for cycling, a picnic or stargazing, so each activity uses different weather signals and different tolerances.

The result is a planning score from 0 to 100. Scores of 75 or higher are shown as GO, scores from 50 to 74 as WAIT, and lower scores as NOT TODAY. These are practical planning recommendations, not safety clearances or professional advice.

Why we score a window instead of one perfect hour

Weather tools can be misleading if they cherry-pick a single unusually good hour. GoodDayTo searches upcoming conditions and scores usable multi-hour windows. The window score blends the average score with the weakest hour in that period, so a shower, gusty hour or temperature spike cannot disappear inside an otherwise attractive average.

Weather signals we use

• Temperature and apparent temperature — used differently for physical activities, outdoor jobs and leisure.
• Precipitation probability and measured forecast precipitation — especially important for laundry, washing a car, riding and picnics.
• Wind and wind gusts — critical for cycling, motorcycling and exposed outdoor activities.
• Relative humidity — particularly useful for estimating whether outdoor laundry conditions are favourable.
• Cloud cover — important for stargazing and relevant to beach conditions.
• UV index — used as a caution factor for exposed physical activities and beach weather.
• Day/night status — used where visibility and daylight materially change the activity.
• Weather codes — thunderstorm signals can cap scores rather than letting a good temperature hide a serious weather concern.

Activity-specific logic

Every activity has its own scoring model. Laundry benefits from lower humidity, low rain risk and a useful breeze. Running values comfortable apparent temperature and manageable wind. Cycling and motorcycling penalise rain, wind and gusts more heavily. Football rewards comfortable, drier conditions with manageable wind, while playground visits also account for UV and practical daylight. Exterior painting strongly penalises rain risk, high humidity and stronger wind because a single dry hour is not enough for a useful working window. BBQ and picnic scoring cares about rain, outdoor comfort and wind. Beach scoring values warm conditions while treating strong wind and very high UV as cautions.

GoodDayTo also shows the main factors that helped or hurt the live score. That explanation is generated from the same forecast values used by the score, so the displayed reasons are not generic filler.

Does the time actually make sense?

GoodDayTo also considers whether an activity normally makes sense at that time of day. A technically dry, calm evening should not make Golf the best evening suggestion, just as a clear afternoon should not make Stargazing a daytime recommendation. GoodDayTo also checks whether that time of day makes practical sense for the activity.

Golf, lawn mowing, gardening, exterior painting and outdoor laundry strongly favour normal daytime hours. Hiking, cycling, motorcycling, beach visits, playground trips and kite flying favour daylight but can allow some evening flexibility. Football and tennis can extend into early evening, but GoodDayTo does not assume floodlights. BBQ and picnic naturally fit afternoon and evening, while dog walking and running are more flexible. Stargazing is deliberately restricted to evening and night conditions when darkness is appropriate.

These rules are designed around typical everyday use, not absolute bans. A lit driving range, night run or twilight ride can still be possible in real life; GoodDayTo simply avoids presenting those edge cases as the default best activity for most people.

Safety caps

Some conditions should not be treated as just another small deduction. When thunderstorm codes, freezing drizzle or rain, snow, fog, very strong gusts or extreme apparent temperatures appear in the relevant forecast, GoodDayTo can cap affected activity scores where those conditions materially change the activity. This prevents an otherwise pleasant temperature from producing an unrealistically positive result.

Local warnings, road conditions, beach flags, currents, lightning alerts, trail closures and official emergency information can still override any GoodDayTo result. Always use local official information where safety matters.

Stargazing is different

Stargazing needs more than a generic night-time weather forecast. When astronomy data is available, GoodDayTo combines cloud, rain and wind with astronomical darkness, moon phase, moon illumination and whether the moon is above the horizon. Bright moonlight can reduce the visibility of faint objects even under a clear sky.

We do not currently pretend to measure local light pollution, atmospheric seeing or transparency from the browser. Those limitations are stated because a trustworthy score should be clear about what it does not know.

What GoodDayTo does not claim

GoodDayTo is not a certified safety system, a medical heat-risk service, a marine forecast, a road-surface sensor or a substitute for official warnings. The score is a practical interpretation of available forecast inputs for everyday planning.

We also avoid inventing readings that a browser or forecast provider cannot genuinely supply. If a future activity needs data we cannot measure reliably, we will either add a legitimate source, state the limitation clearly, or not claim to score that factor.

Location and privacy

You can search for a town or allow the browser to provide your location. The site uses the resulting location to request forecast data. Favourites and unit preferences are stored locally in the browser so they can work without creating an account. Shared result text does not include latitude or longitude.

Why the model will keep improving

GoodDayTo is designed to be auditable. We review activity thresholds, edge cases and user intent before adding new activities. When the scoring method changes materially, we update this methodology and the relevant activity guidance rather than silently changing the meaning of the score.