Have you ever wished you’ve been prepared in the morning if it’s going to rain later in the day? This way, you wouldn’t forget to take your umbrella to work. The weather forecast is what you need. But we’re all humans, and sometimes you forget to look at it, especially during a busy morning.

This post will show you how to create a Python script to get the weather forecast. Specifically, it will generate the notification to let you know if it’s going to rain today. We will get the weather forecast for the day from Open Weather, send a notification to the Telegram messenger, and then schedule the code to run every day at 7.00 in the morning using Seamless Cloud. The script is less than 20 lines of code, so even if you don’t know Python – you will be able to implement it yourself. Let’s get started.

Getting the weather forecast

We’re going to use https://openweathermap.org/ to get the weather forecast using Python. It is free to use. The only thing you need to do is to create an account to get your API key. Please sign up here. After you’ve signed up, you can find your API key on this page. Save it somewhere. We’re going to use it later.

It takes time for the API key to be activated. I waited for around 30 minutes. If the Python script returns an error that looks like “Invalid API key. Please see http://openweathermap.org/faq#error401 for more info.” you need to wait a bit before it gets activated.

Set up a messenger to receive notifications

We’re going to use Telegram to receive notifications. You would need to create a bot that will send messages. Please follow the documentation and create the bot. You need to create a channel, make it public, and invite the bot into the channel.

This is an example of a channel that I’ve created. In this case, the channel name is rain_forecast. Note that the text at the top (“Rain Forecast”) is just for display purposes. To address our channel from Python, we need to use @rain_forecast as a channel name.

The code

Okay, here is the code.

import os

import requests

WEATHER_API_KEY = os.getenv('WEATHER_API_KEY')
LATITUDE = os.getenv('LATITUDE')
LONGITUDE = os.getenv('LONGITUDE')
BOT_API_KEY = os.getenv('BOT_API_KEY')
CHANNEL_NAME = os.getenv('CHANNEL_NAME')

if __name__ == '__main__':
    resp = requests.get(
        f"https://api.openweathermap.org/data/2.5/onecall?lat={LATITUDE}&lon={LONGITUDE}&APPID={WEATHER_API_KEY}")
    forecast = resp.json()['daily'][0]
    today_weather = forecast['weather'][0]['description']
    if 'rain' in today_weather:
        requests.get(f'https://api.telegram.org/bot{BOT_API_KEY}/sendMessage',
                     params={'chat_id': CHANNEL_NAME,
                             'text': 'It\'s going to rain today' + u'\U00002614' + ', take your umbrella with you!'})

You can also find the full version of the code here.

Script Parameters

At the top of the file, we have declared five variables. The first one is WEATHER_API_KEY – this is the key from your Open Weather account. LATITUDE and LONGITUDE are coordinates for the location where you live (to get them, just google “<your city name> coordinates”). BOT_API_KEY is the key you’ve got during the Telegram bot set up. CHANNEL_NAME is the name of the public channel you’ve created with @ at the beginning. In my case, it’s @rain_forecast. You would need to enter the name of your channel that you’ve created.

How the script works

The first request in the script is the call to Open Weather API. Then we get the description of the weather forecast for the current day. It will contain the word rain if it’s expected to rain. If we find the word rain – we make a request to the Telegram API asking to send a message from our bot. That’s it!

Scheduling the script to run daily

You may have noticed that this blog post is a part of the Seamless Cloud blog. We’re developing a platform for automating routine tasks using Python. Executing a Python code on schedule is a prevalent use case.

You can sign up here. In fact, on our platform, you don’t even have to write any Python code to use the script from this article. Just go to the Templates tab and find a template that’s called “Get a notification if it’s going to rain today.” Hover over it and click “Use.”

The last thing is to fill out the Parameters – values I’ve described in the Script Parameters section.

After you fill in all the Parameters, click Run, and make sure everything works. You can also set up a schedule for this code to run. For example, I’ve set up the script to be executed every day at 7.00 AM.

This is how the notification looks like:

Congratulations! You’ve learned how to get a weather forecast using Python and make it actionable. As a next step, you can make the script more complicated by analyzing more weather data. You can find documentation about Open Weather API here. There are many things you can do. The sky is the limit.

You can read more of our blog here.