Build a Raspberry Pi Weather Station that Emails Daily Weather Data

Turn your Raspberry Pi into a reliable personal weather station that sends you real‑time temperature, humidity, and rainfall updates via email. This guide walks you through the required hardware, wiring, housing, and coding steps to get your station up and running in just a few hours.

1. Supplies

• Raspberry Pi B (or newer model) with power supply
• Ethernet cable (or Wi‑Fi adapter for wireless setups)
• Prototyping breadboard and jumper wires
• Humidity & temperature sensor – DHT11 (or the more accurate DHT22)
• Analog rain gauge (e.g., a simple tipping bucket)
• Weather‑proof enclosure (polycarbonate or acrylic)
• Hot glue gun & glue sticks
• Drill with a selection of bits (for mounting the gauge and wiring)
• Optional: BME280 or BMP280 barometric pressure sensor (for future rain‑chance calculations)

2. Assemble the Circuit

Connect the components as follows:

• Power: Attach the sensor’s VCC pin and the rain gauge’s power input to the Pi’s 3.3V pin.
• Ground: Connect the sensor’s GND to a Pi ground pin.
• Data Lines: Wire the DHT11 data pin to GPIO 16 (or any free GPIO). Hook the rain gauge’s data output to additional GPIO pins (e.g., GPIO 7, 13, 15, 18).

3. Build the Housing

1. Drill mounting holes in the rain gauge at 1", 1.5", 2", 2.5", and a bottom hole for drainage. 2. Carve out slots in the enclosure for the Ethernet and power cables, as well as the sensor leads. 3. Secure the gauge to the back of the housing with hot glue, ensuring the drainage holes remain open. 4. Route the sensor and gauge wires through the housing, sealing all penetrations with hot glue to keep moisture out. 5. Place the Raspberry Pi and the breadboard inside the enclosure, connect the Ethernet and power cables, and power on.

4. Program the Humidity Sensor

Install the Adafruit DHT library:

git clone https://github.com/adafruit/Adafruit_Python_DHT.git
cd Adafruit_Python_DHT
sudo apt-get install build-essential python-dev
sudo python setup.py install

Test the sensor with a simple script:

import Adafruit_DHT as dht
sensor = dht.DHT11
pin = 16
humidity, temperature = dht.read_retry(sensor, pin)
print(f"Humidity={humidity:.1f}%  Temp={temperature:.1f}°C")

If the output shows valid values, the sensor is wired correctly.

5. Automate Email Reports

Install mailx (or msmtp) to send emails from the Pi. Create a cron job that runs the sensor script every 30 minutes and pipes the output to an email address:

*/30 * * * * /usr/bin/python /home/pi/weather.py | mailx -s "Pi Weather Update" you@example.com

Adjust the cron schedule to suit your reporting frequency.

6. Future Enhancements

When you’re ready, add a BME280 or BMP280 sensor for barometric pressure. With the pressure trend, you can calculate the probability of rainfall and include it in your email alerts.

Happy building and enjoy the daily weather data straight to your inbox!