Abstract

The extreme values of precipitation and temperature are an important measure of the effects of weather and climate on the region. Changes in these parameters under future climate conditions could lead to substantial impacts on hydrologic conditions and, potentially, on water management. Global climate models provide the main guidance in assessing future climate impacts, but these models cannot adequately simulate the weather, terrain, and land-­‐surface processes that produce local extremes of temperature and precipitation. Recent developments with regional climate models have provided more realistic simulations of extreme events under climate change scenarios. For this report, we have examined the projected future changes in extreme events over the areas critical to Seattle City Light’s operations using simulations from a regional climate model.