Start with the answer
Hydrologists pay in Tucson, AZ and Washington-Arlington-Alexandria, DC-VA-MD-WV
The May 2025 BLS OEWS median for Hydrologists is $81,640 per year in Tucson, AZ. It is $152,730 per year in Washington-Arlington-Alexandria, DC-VA-MD-WV. Tucson, AZ is 46.5% below Washington-Arlington-Alexandria, DC-VA-MD-WV on the published median.
Both rows use SOC 19-2043 and the same annual wage metric. Median means the middle of each area's published wage spread. It is not one worker's pay. The larger median is not proof that one place gives a better job or a better result. It is one wage fact from one source period.
BLS lists 80 wage and salary jobs in Tucson, AZ and 50 in Washington-Arlington-Alexandria, DC-VA-MD-WV. Those are survey job counts, not open posts. Read pay, job scale, local share, and price level as separate facts before you make a choice.
Evidence: bls-oews-may-2025 · Rule: same-soc-same-metric-pair · nominal-median-gap · employment-not-openings