Initializing the Weather Research and Forecasting (WRF) Model in Complex Coastal Regions

Coastal counties of the US are home to approximately 40% of the nation’s population. These people often experience different day-to-day weather than people in nearby non-coastal counties. However, NWP often struggles to accurately capture coastal circulations that can lead to changes in temperature, humidity, clouds, and precipitation. Our research focuses on improving coastal forecasting and the simulation of sea breeze circulations in regions with complex geography. Through numerous numerical studies of sea breeze circulations in the Mid-Atlantic region and Florida, we determined that careful initialization of the Weather Research and Forecasting model through the WRF Preprocessing System (WPS) is critical for achieving more accurate results. For example, sea breeze circulations are very sensitive to the spatial resolution of the coastline and the land-sea temperature gradient. Despite having a community of 39,000 registered users, there are very few WRF studies that supplement the default geographic input data with high-resolution datasets (land use, elevation, etc.) that exist elsewhere or including historical SST data in their model. This may occur in part because such tasks are not straightforward and require additional technical knowledge. This presentation will provide details on incorporating higher spatial resolution land and sea-surface datasets. We will discuss the issues that we ran into, how we handled these challenges, and ultimately quantify the improvements by statistically validating the model with observational data.