Using Radios in Noisy, Windy or Wet Conditions
No radio can differentiate between the spoken word and background or wind noise, (although radios with Digital Signal Processing are pretty good at this). The Mic picks up the loudest sound and transmits that sound while suppressing the weaker sound. If your voice is weaker than the background noise then other users will hear the noise.
Make sure the Mic is close to your lips no more than 2cm (1 inch). This will ensure your voice is louder than the Noise.
Turn you back to the wind to shelter the Mic. In very windy conditions cup the Mic to your mouth.
Machine or Music Noise
Follow the procedures above and if possible move a few metres away from the noise source. Sound levels decline rapidly with distance.
Rain and Wet
If a drop of water blocks the Mic port the Mic will become 'deaf' i.e. not as sensitive and your voice will sound fainter to other radio users.
Shake the radio to remove excess water and possibly blowing on the Mic will help clear the Port too.