If you can add some dummy values to those two columns, UWG will run fine, and won’t change the results. The original UWG model incorporated the latent heat impact from precipitation in it’s heat balance, but was later remove due to its difficulty in validation, the poor quality precipitation data from weather sensors, and (it was assumed) the marginal impact it has on heat island outcome.
The absolute humidity is internally derived in UWG based on the relative humidity, temperature and air pressure, so should also have no impact.
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