Libraries I am using for this example:
Adafruit DHT Sensor Library
Adafruit Unified Sensor Library
Some of the posts discussing this topic:
https://forum.arduino.cc/t/not-getting-negative-temperature-readings/664195
https://forum.arduino.cc/t/dht22-negative-temperature/695993
https://forum.arduino.cc/t/my-dht11-data-reading-value-temperature-humidity-got-negatif-and-ac-temp-zero-in-oled/932992