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To close, I'd like to review a few forecasting techniques for convection.
The first point I'd like to make is that the atmosphere is rarely very unstable at 12Z, when the morning rawinsondes are launched. This presents a problem if you're trying to forecast convection that afternoon.
Remember the Fort Worth soundings? The only place the temperature really changed was near the ground, because of diurnal heating and cooling. Meteorologists will often assume that the temperature much above the ground doesn't change much, and will get forecasted or actual surface temperatures and dew points for mid-afternoon and compare the temperature of that parcel, if lifted, with the 12Z sounding.
Another technique, becoming more and more widespread, is to take the data from a numerical model and construct complete forecasted soundings. Stability can be assessed from these forecasted soundings, or the boundary layer air temperature and dew point can be corrected first using observations or forecasts.
Once you've got your mid-afternoon temperature forecast or model forecast, you might want to know something about the convection it might produce. In the previous module, you learned how to estimate cloud base: that's just the height at which the lifted air parcel becomes saturated. How about cloud top? You can determine that from the sounding as the height at which the lifted air parcel finally becomes stable again. That point is called the equilibrium level. If the thunderstorm will be producing an anvil, this is the height at which the anvil will be located.
Technically, ascending air hits the equilibrium level with considerable vertical velocity, and continues ascending a ways before it comes to a stop and sinks back down. The portion of the cloud produced by this process is called the overshooting top, and such a cloud feature marks the location of the strongest updraft.
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