Observation · Historical context · Practical responses
American West
Water Observatory
Explore the American West's water conditions alongside its historical moisture record. Read drought coverage, selected river and well observations, mountain snow, and Colorado River reservoir context together; then connect local conditions to practical water and land investments.
Historical moisture balance
1934: a geographic view of drought.
Drier ← PDSI → Wetter · Census geographic outlines · Annual averages can hide severe individual months.
Colorado
-4.82Annual PDSI in 1934
The historical chart shows statewide annual averages of NOAA's monthly Palmer Drought Severity Index for 1895–2025, using years with all twelve valid months. Negative values indicate drier conditions; positive values indicate wetter conditions. Compare periods with the 1930s for context. Similar index values do not establish similar erosion, impacts, or future risk.
A moisture index is not groundwater storage, water allocation, or a forecast of another Dust Bowl.
Colorado · 131 complete years
Shaded band: 1930–1939. Historical similarity alone does not establish similar soil erosion or future risk.
Accessible data table · 1934
| State | Annual PDSI |
|---|---|
| Washington | -0.64 |
| Oregon | -2.73 |
| California | -2.14 |
| Nevada | -4.59 |
| Idaho | -3.77 |
| Montana | -2.07 |
| Wyoming | -6.34 |
| Utah | -5.12 |
| Arizona | -2.75 |
| Colorado | -4.82 |
| New Mexico | -3.69 |
| North Dakota | -5.23 |
| South Dakota | -6.11 |
| Nebraska | -5.6 |
| Kansas | -5.47 |
| Oklahoma | -2.2 |
| Texas | -2.78 |
NOAA record retrieved Oct 6, 2026. Download original monthly file ↗