How do I interpret an image of a spectrogram of an audio wind signal?
The almost steady colored part between 1 s and 35 s, and below about 30 Hz may be the sign of a   low-frequency, continuous noise that seems to be common to mild winds. There seems to be occasional gusts of wind around 12 s to 17 s or 22 s to 25 s. However, the needle aspect of the  spectrogram coefficients may suggest to modify the window, and the little information on frequencies above 256/512 Hz would suggest to look closer at the low frequencies, possibly with a linear frequency scale to better see details.