Midwest's growing crops help boost humidities
The country's most humid air sits over a large swath of the Midwest on Friday -- more
humid over sections of the Heartland than the perennially muggy Gulf Coast. That's not
an accident. The Midwest is home to much of this country's most productive cropland
and crops send moisture airborne through a process known as transpiration -- the
evaporation of water from the leaves of plants. Strolling by a mature cornfield, you'll
feel a surge of moisture. Dew points, the preferred measure of moisture among
meteorologists, are expected to reach the 70s later Friday in Chicago and could surge
to near 80 degrees in sections of Missouri and Iowa -- a level most often associated
with tropical rain forests.
Truly hot weather continues to be a surprisingly rare commodity this summer in
Chicago. The highest temperature to occur has been 91 degrees. Not a single summer
in the past 80 years (since 1928) has failed to produce a higher temperature.
DOLLY'S TORNADO-PRODUCTION SPARSE BUT ITS RAINFALL HAS BEEN PLENTIFUL
The remnants of Hurricane Dolly managed only two twisters Thursday -- surprisingly
few for a landfalling Gulf Coast tropical cyclone. However, rains have been prolific.
Laguna Madre, Texas, was hit by more than 16 inches of rain.
--Tom Skilling, Chief Meteorologist, WGN-TV/Chicago Tribune