The column integrated water vapor (CWV)‐based local wave activity (LWA) is adapted to examine the response of the hydrological cycle and extremes of the Asian summer monsoon in CMIP5 simulations under the RCP8.5 forcing scenario. A tight linear relationship between CWV LWA ( urn:x-wiley:00948276:media:grl58169:grl58169-math-0001) and its sink ( urn:x-wiley:00948276:media:grl58169:grl58169-math-0002, which measures the intensity of the local hydrological cycle and extremes, affords a simple scaling framework for the hydrological cycle intensity in terms of the contributions from (i) ratio of moisture participating in the hydrological cycle, (ii) stirring length scale, (iii) background moisture gradient, and (iv) hydrological cycling rate. Future CWV LWA over the broad Asian monsoon region shows a large increase (~35%), attributable largely to the increase of the background moisture. The scaling analysis reveals a distinct mix of the contributing factors for the increase in urn:x-wiley:00948276:media:grl58169:grl58169-math-0003 between East Asian and Indian monsoon regions, despite both experiencing sizable increase of urn:x-wiley:00948276:media:grl58169:grl58169-math-0004.