Temperature advection at the surface can be estimated by examining the degree to which the geostrophic wind at the surface crosses the 1000 mb to 500 mb thickness contours. If the wind flows from larger to smaller thickness values, warm air advection is probably occurring. If the wind flows from smaller to larger thickness values, cold air advection is probably occurring. The guidance links for this section will take you to National Weather Service numerical model predictions. Multi-panel plots for each model are displayed.  Examine each model's forecast mean sea level pressure and 1000 mb to 500 mb thickness patterns.