Inches -99 1901-2000 base period 1901-2000 4801 Wyoming CD 1. Yellowstone Drainage 11.0 81 9.91 1.09 4802 Wyoming CD 2. Snake Drainage 15.21 89 13.52 1.69 4803 Wyoming CD 3. Green and Bear Drainage 4.34 70 4.37 -0.03 4804 Wyoming CD 4. Big Horn 3.24 37 3.87 -0.63 4805 Wyoming CD 5. Powder, Little Mo and Tongue Drainages 1.96 9 3.21 -1.25 4806 Wyoming CD 6. Belle Fourche Drainage 1.64 7 3.04 -1.4 4807 Wyoming CD 7. Cheyenne Niobrara Drainage 1.28 7 2.39 -1.11 4808 Wyoming CD 8. Lower Platte 1.87 19 2.85 -0.98 4809 Wyoming CD 9. Wind River 3.13 31 3.95 -0.82 4810 Wyoming CD 10. Upper Platte 3.11 45 3.54 -0.43