Heihe's winters are harsh, with temperatures plummeting as low as -38°C in January and staying below freezing until March. Spring brings a gradual warming, with temperatures slowly rising above 0°C by May. Summers are mild, with highs around 34°C in July, but temperatures drop significantly by autumn. Autumn is cool and crisp, with temperatures returning to near-freezing levels by November. Winters return by December, bringing extreme cold once again.