Muddy weather is mountain bike weather. To avoid mud flying right into your face while riding, the Canadians from Race Face have developed the Mud Crutch:
Simply mount it to the fork of your bike and you're protected from mud and water splashes.
• to be mounted between fork bridge and fork crown via velcro fastener
• dimensions: for 80-120 mm travel (small), for 120-160 mm travel (medium), for 160-203 mm travel (large)
• material: Mylar