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FREEZING LEVEL CALCULATION:

Per FAA "A standard temperature lapse rate is when the temperature decreases at the rate of approximately

Easy enough to use this to calculate freezing level.

**3.5 °F**or 2 °C per thousand feet up to 36,000 feet"Easy enough to use this to calculate freezing level.

CLOUD BASE CALCULATION:

"As moist, unstable air rises, clouds often form at the altitude where temperature and dew point reach the same value. When lifted, unsaturated air cools at a rate of

Also pretty easy.

**5.4 °F**per 1,000 feet and the dew point temperature decreases at a rate of 1 °F per 1,000 feet. This results in a convergence of temperature and dew point at a rate of 4.4 °F. Apply the convergence rate to the reported temperature and dew point to determine the height of the cloud base."Also pretty easy.

But wait does air cool at 3.5F or 5.4F per 1,000ft??

I think the issue here is whether we're talking about dry lapse rate or saturated lapse rate. Or an average. Per wikipedia, looks like 5.4F is dry, wet is 2.7F.

So my question is, wouldn't it be better to calculate freezing level by using 5.4F until you get to cloud base (which is saturation level) and then switch to 2.7F?