Rain warnings

A rain warning turns on shortly before rain reaches your location and stays on while it rains. You set how early, and optionally how much rain is worth a warning: "Laundry, 60 minutes ahead", "Windows, 15 minutes ahead, only for a heavy burst". Add as many as you like.

Rain warnings need no blueprint and no template: each one is a device with two entities that an automation can trigger on.

Adding a warning

Open Settings > Devices & services > DWD Precipitation, then select Add rain warning on the location's entry. The form asks for:

Field	Default	Meaning
Name		What the warning is for, such as Laundry. Each warning of a location needs its own name
Lead time	30 min	How many minutes before the rain the warning turns on, from 5 to 120 in steps of 5
Minimum rain in total	empty	Only warn about a rain event that brings at least this much, measured and forecast (mm)
Minimum rain in the wettest hour	empty	Only warn about an event whose wettest hour brings at least this much (mm)
Minimum rain in the wettest 10 minutes	empty	Only warn about an event whose wettest 10 minutes bring at least this much (mm), for short heavy bursts
With several minimums	one is enough	Whether an event has to reach one of the minimums you set, or all of them

Leave all minimums empty to be warned about every rain event.

To change a warning later, open its menu on the entry and select Reconfigure. Deleting it removes its device and entities. Adding, changing or deleting a warning reloads the integration; the values come back within a few seconds.

Entities

Each warning is a device of its own, named after the location and the warning: a warning Laundry at the location Home is the device Home Laundry with:

Entity	Entity id	States
Rain warning	binary_sensor.home_laundry_rain_warning	on while it rains or is about to, off otherwise
Rain warning status	sensor.home_laundry_rain_warning_status	dry, soon or rain

The status sensor has the details as attributes; the on/off entity has none.

Status	Meaning
rain	a rain event that passes the warning's minimums is falling now
soon	none is, but one that passes them starts within the lead time
dry	neither

Renaming a warning renames its device and entities; the entity ids stay as they were, so your automations keep working.

Both entities are unknown while there is nothing to judge yet, for example for a few seconds after a restart, and unavailable when the radar forecast is out of date, like the other forecast sensors.

Attributes

Attribute	Description
event_id	The id of the rain event the warning is about, as in Rain events
start	When that event starts (or started), ISO-8601 in UTC
mm	Its total: measured so far plus forecast, in mm
peak_1h	The rain in its wettest hour, in mm
peak_10min	The rain in its wettest 10 minutes, in mm
type	The measured precipitation type of the event, such as rain or snow, as in Rain events; null while it is only forecast, since DWD forecasts no type

All of them are null while the status is dry, and none is recorded in history.

How a warning decides

A warning has no rain logic of its own: it reads the rain events the integration tracks for the location, the same events the Rain events sensor shows. So what counts as rain is the option Only count rain heavier than in the Rain events and rain warnings section, and the forecast reaches two hours ahead.

• The lead time counts from when the radar data arrives in Home Assistant. The data comes every 5 minutes, so a warning can turn on up to 5 minutes later than the lead time says. DWD's data is already a few minutes old when it arrives (see Release timing), so a short lead time leaves less time than it suggests: use at least 10 or 15 minutes for anything that takes a while.
• The minimums are compared with the event's total: what has fallen so far plus what is forecast. An upcoming event has only its forecast.
• Once an event has reached the minimums, it keeps counting until it has ended, even if a later forecast makes it smaller. A shower does not switch the warning off and on again just because its forecast changed.
• A forecast often loses a small shower for one release and finds it again in the next. A warning that was soon stays soon for that one release; if the shower is still missing in the next one, the warning goes back to dry.
• These two memories are kept in memory only. After a restart, an event is judged again on its current values.

Good to know

• Rain warnings use the rain-events tracker, but not the Rain events sensor: they work with the option Add the "Rain events" sensor off. While a location has a warning, the integration fetches the radar analyses it missed (a small part of each file) and keeps a small record of recent rain on disk. Deleting the last warning, with that option off, deletes that record.
• The amounts are radar only, like the Rain events they come from.
• Rain warnings need Home Assistant 2025.4 or newer.