How GoodDayTo judges garden-watering weather
Watering is not simply better when the sky is dry. If meaningful rain is likely soon, watering may be unnecessary. If the afternoon is very hot, more water can be lost to evaporation. If wind is strong, sprinklers and fine spray can drift away from the area you intended to water. GoodDayTo combines those forecast signals and favours calmer, cooler periods with a lower chance of rain.
The model prefers morning and early evening because those periods often reduce evaporation compared with the hottest part of the day. It does not claim that one schedule is correct for every plant. Containers, new seedlings, mature trees, lawns and drought-tolerant plants can need very different amounts of water.
The most important missing input is the soil itself. A weather API cannot feel whether the root zone is dry. The score therefore answers a narrower question: if you already know watering is needed, when does the forecast make the job more practical?
Why forecast rain lowers the score
GoodDayTo treats a rising rain probability and measured precipitation as reasons to wait because natural rainfall may do some or all of the job. That does not mean every forecast shower will deliver enough water. A brief light shower can wet the surface without reaching deeper roots, so the actual garden still needs checking.
Why wind and heat matter
Stronger wind can make overhead watering uneven and increase drift. High temperature and strong sun can increase evaporation from exposed surfaces. The model therefore tends to favour a calmer morning or evening when those conditions are available.
What the score cannot know
GoodDayTo cannot see soil moisture, plant species, root depth, irrigation design, mulch, recent manual watering, water pressure, local drought restrictions or hosepipe bans. It also cannot tell whether forecast rainfall actually reaches your property at the predicted amount. Check the soil and follow local water-use rules before acting on the score.
- Rain probability
- Measured precipitation
- Air temperature
- Wind & gusts
- UV index
- Time of day
Practical checks before you go
- Check the soil before watering; a dry surface does not always mean the root zone is dry.
- Follow local watering restrictions even when GoodDayTo shows GO.
- Water the plant zone rather than automatically watering every part of the garden.
Frequently asked questions
Why can a sunny afternoon score lower than the morning?
Heat, UV and evaporation can make the afternoon less efficient, while a cooler calm morning may waste less water.
Does WAIT mean rain will definitely water the garden enough?
No. It means forecast conditions make waiting reasonable; actual rainfall amount and soil moisture still need checking.
Can I use this for pots and containers?
Yes as a weather-timing guide, but containers can dry much faster than garden soil and may need their own schedule.
Does GoodDayTo know about hosepipe bans?
No. Local restrictions must be checked separately and always take priority.
What if rain is forecast later?
A later shower can be a good reason to wait, but forecast rain may be lighter or more local than expected. Check the soil and reassess after the rain rather than assuming the forecast amount reached every plant.