Ticker for February 18, 2002

                
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February 18, 2002  February 18, 2002  February 18, 2002  February 18, 2002


The Wet Bulb Effect: It's Not Just For Frozen Precip

A few weeks ago, the Ticker discussed the "wet bulb effect", by which
evoprating precipitation caused temperatures to plummet.  The full text
is here:

https://content.mesonet.org/ticker/archive/tickselect.cgi?mo=02&da=05&yr=2002

A movie of this afternoon's Mesonet temperature observations demonstrates
that the wet bulb effect shows up quite well at moderate temps, too:

https://content.mesonet.org/ticker/archive/20020218/tair.mov
(*warning* it's about 380 KB!)

Very, very light precipitation (not enough to accumulate) is associated
with that travelling blob of lower temperatures.  It doesn't take much
evaporation to drop temperatures, given the right conditions.