· Updated
Set Up Weather Alerts on Your Home Weather Station
By Lennart Steen · Hands-on guides from the people building the platform
Your weather station collects data every minute, but you do not have time to watch it constantly. The real value comes from being notified when something important happens: a temperature drop that signals a frost risk, a wind gust that might damage property, a pressure fall that announces a storm, or an air quality spike that affects health.
This guide shows how to set up automated weather alerts for your Davis station, from built-in options to more flexible approaches.
What do you need for any alert system?
Every weather alert system needs three things. A condition is what you want to hear about: a reading crossing a level, a reading moving too fast, or an event such as rain starting. A delivery channel is how the notification reaches you, usually email or a webhook. The third is simply a station that is online and reporting. When the condition is met, the system sends the notification.
The data always comes from your station, so it needs to be online and reporting to WeatherLink. From there, an alert system (whichever of the three options below you pick) checks the readings and sends the notifications.
Option 1: Pro Weather alerts
If you use Pro Weather, alerts come built in with the Pro plan and the free trial, and configuring one takes about a minute:
- Open your Pro Weather dashboard and go to Alerts
- Under Alert me when, choose a condition
- Enter a threshold, if that condition needs one
- Choose how to be notified (email, webhook, or both) and whether it should repeat while it lasts
- Choose Add alert
You can add up to 25 alerts per site, and the full option-by-option walkthrough is in the alerts documentation.
There are 42 conditions, in three kinds:
| Kind | What it covers |
|---|---|
| Threshold | A reading crosses a level you set: temperature, feels-like, dew point, humidity, pressure, wind gust and average, rain today and rain rate, UV, solar, PM2.5, PM10, CO₂, soil, leaf wetness, lightning, water leaks, and station health (data age, battery, reception) |
| Rate of change | A reading moves faster than you allow: pressure falling or rising over 3 hours, temperature falling or rising over 1 hour |
| Event | Something happens, no threshold needed: it started raining, an all-time record was broken, a reading was rejected as a spike, a weather-service upload is failing |
The rate-of-change alerts are the actual storm signals, and a plain threshold cannot express them: a 3 hPa pressure fall in 3 hours is the classic gale warning at sea, whatever the absolute reading is.
Delivery is email, a signed webhook, or both, per alert. The webhook posts JSON to your own server with an HMAC-SHA256 signature so your receiver can verify the request really came from your station's alerts, which turns an alarm into an action: close a greenhouse vent, flip a smart plug, post to a chat room. The docs carry a verification snippet.
The alerts are latched: you get one notification per episode, and the alert re-arms only once the condition clears (with at least 30 minutes between notifications), so a value hovering around your threshold does not flood your inbox. For conditions where a reminder is useful, such as a station that has gone offline or a frost that lasts all night, set While it lasts to repeat every hour, 3, 6 or 12 hours, or once a day, for as long as it stays true.
What the most-used alerts are good for:
| Alert | Typical uses |
|---|---|
| Temperature (above/below) | Frost warnings in spring and fall, heat warnings, greenhouse and cold-frame monitoring |
| Wind gust above | Damaging gusts, documenting wind events, calling off unsafe outdoor plans |
| Rain rate above, it started raining | Heavy rain that could indicate flooding, knowing when a shower arrives |
| Pressure falling (3 h) | The storm signal: a front or low approaching, hours before the wind does |
| PM2.5 above | Wildfire smoke events, poor air quality days, local pollution spikes |
| Data older than | The one every site should have: it tells you your station went quiet |
Two of these deserve a closer look. For frost, do not set the threshold at freezing itself: your temperature sensor sits well above the ground, where the air is often warmer than the grass below it, so a lawn can frost while the thermometer still reads +2 °C. Our guide to predicting frost with your weather station covers what threshold to pick and why the dew point matters. For wind, alert on gusts rather than the average: gusts are what do the damage, and they routinely run well above the sustained wind speed. Wind gusts vs sustained wind explains the difference.
Option 2: WeatherLink paid plan alerts
The WeatherLink Pro and Pro+ subscriptions include their own alert system. You can configure email and push notifications through the WeatherLink dashboard based on threshold-style conditions.
The limitation is that these alerts are tied to the WeatherLink platform and its interface. Your notifications come from WeatherLink, not from your own site or service, and they are only included if you pay for one of the upgraded plans.
Option 3: DIY alerts with the WeatherLink API
For maximum flexibility, you can build your own alert system using the WeatherLink v2 API. This is the most technical option but allows you to:
- Send alerts to multiple channels: email, SMS, Slack, Discord, or a custom webhook
- Apply complex logic, such as combining multiple sensor readings
- Log alert events to your own database for analysis
- Control every aspect of how and when notifications are sent
The basic approach is to periodically fetch current conditions from the API, compare the readings against your threshold values, and send a notification when a threshold is crossed. You could deploy this as a small script on a Raspberry Pi, a serverless function, or a scheduled task. You will need a v2 API key, which is free to generate from your WeatherLink account.
How do the alert options compare?
| Feature | Pro Weather alerts | WeatherLink alerts | DIY API alerts |
|---|---|---|---|
| Setup time | Minutes, in-dashboard | Minutes, in WeatherLink | Hours of development |
| Notification channel | Email + signed webhooks | Email + push | Any (email, SMS, webhook) |
| Conditions | 42: thresholds, rate-of-change, events | Thresholds | Any logic you write |
| Repeat behavior | Latched per episode, optional re-notify (1 h to daily) | Platform-defined | You implement |
| Cost | Included with Pro Weather | Requires WeatherLink Pro/Pro+ | Free + your development time |
| Maintenance | None | None | You maintain the script |
Which alert option should you choose?
For most Davis owners, Pro Weather alerts hit the sweet spot: they are quick to configure, require no coding, and cover far more conditions than the readings on the dashboard, including the rate-of-change storm signals and station health checks. The latching behavior means you get notified when something changes without being spammed, and the webhook option covers the "make something happen" cases without writing a polling script.
If you need alerts routed to SMS or a chat platform directly, or want to combine multiple sensors with custom logic, a DIY approach with the WeatherLink API gives you full control. Just be aware that you are taking on the development and maintenance of that system. A middle path exists too: point a Pro Weather webhook at a few lines of your own code, and you get custom routing without building the polling and threshold logic yourself.
If you already have a WeatherLink Pro or Pro+ subscription, their built-in alerts may already meet your needs, but they are tied to the WeatherLink ecosystem.
Common questions
Can my weather station send me a text when it freezes?
Not directly, since a Davis station has no way to message you on its own. But its data reaches WeatherLink, and any service that can read the WeatherLink v2 API can watch it and notify you. Pro Weather sends email alerts, which most phones surface as notifications, and its webhooks can drive an SMS gateway; the WeatherLink app can send push notifications on paid plans; and a DIY script can send true SMS through a gateway service.
What does it mean that alerts are latched?
A latched alert fires once when its condition is met and then stays quiet until the condition has cleared and re-arms, instead of emailing you every five minutes for as long as it lasts. You learn when a frost starts without forty identical messages overnight. If you do want reminders while a condition persists, such as a station that has gone offline, Pro Weather's While it lasts setting repeats the notification every 1, 3, 6 or 12 hours, or once a day.
What temperature should I set a frost alert for?
Above freezing: 2 °C (36 °F) is a sensible starting point. Your temperature sensor sits well above the ground, and on calm, clear nights the ground can be several degrees colder than the air at sensor height. An alert at 2 °C gives you time to protect plants before the lawn actually frosts. Pro Weather also has a sharper tool for the same job: a rate-of-change alert for temperature falling fast over an hour, which catches the evening the ground is about to freeze.
How do I stop false alarms from sensor glitches?
Set spike limits. In Pro Weather these live under Calibration: the largest change you accept between two consecutive readings. A momentary sensor drop-out or radio glitch that jumps further than the weather can is dropped before it reaches your alerts, and there is even an event alert that tells you a reading was rejected, since a failing sensor usually spikes before it dies. In a DIY script, the equivalent is a few extra lines of state-keeping that require a sustained condition before notifying.
Ready to set up alerts?
If you use Pro Weather, open your dashboard and configure your first alert. It takes about a minute, and Data older than is the one worth adding to every site, because it is the alert that tells you all the others have gone blind. Not on Pro Weather yet? Start your site and your alerts will be ready alongside your live weather page in about five minutes.