Boundary Layer » Maximum Temperature Forecasting Maximum Temperature, U.S. Air Force Method
There are several ways to forecast maximum temperature from a single sounding. The U.S. Air Force developed a simple method to make such forecasts, depending on sky conditions. The method works for locations fairly near sea level, away from water, and not expecting an air mass change. We examine this technique below.
If no inversion is present between 4,000 and 6,000 feet (1200-1825 m) above the surface:
- From the morning sounding (1200 UTC in North America), find the temperature at 850 hPa (T850).
- Clear/scattered clouds: Proceed from T850 dry adiabatically to the surface to get TMAX.
- Broken clouds/overcast: Proceed from T850 moist adiabatically to the surface to get TMAX.
If an inversion is present between 4,000 and 6,000 feet (1200-1825 m) above the surface:
- Find the temperature (T) at the warmest point (top) of the inversion.
- From that point, proceed dry adiabatically to the surface.
- The resulting temperature at the surface is TMAX.