UpDate - Vol. 12, No. 39, Page 7
August 19, 1993
State climatologist details July's extreme, hot weather
July climatic conditions in Delaware were truly unusual, according to
Daniel J. Leathers, Delaware state climatologist in the University of
Delaware's Center for Climatic Research.
Leathers shared the following preliminary data for the month of July:
* July 1993 was the seventh hottest July on record for the state
over the last 99 years. (Record keeping began in 1895.)
* The preliminary estimate of the monthly mean temperature for the
state is 78.5 degrees Fahrenheit, or 2.6 degrees above the
99-year mean. The monthly mean temperature is the average of the
daily temperatures for a given month.
* Wilmington recorded 15 days with temperatures at or above 90 F. A
period of eight consecutive days, July 7 through 14, had maximum
temperatures of at least 90 F.
* Wilmington recorded its second highest July cooling degree day
total on record. A cooling degree day is an estimate of the
energy needed for cooling or refrigeration.
* Rainfall was extremely variable across the state. Wilmington
recorded near normal conditions with 4.04 inches, just slightly
below normal. Other areas of the state, especially southern
Delaware, did not fare as well. For example, the Dover area
recorded only about 2.5 inches of rainfall, more than 1.5 inches
below normal, and localized rainfall reports from Sussex County
indicated less than 1 inch for the month.
* Indices representing agricultural conditions across the state
continue to be poor at the end of July. In New Castle County, the
Palmer Drought Severity Index, which measures prolonged drought
or wetness, indicates a continuance of mild drought. The Crop
Measure Index, a measure of short-term drought or wetness,
indicates abnormally dry conditions for crop development. In Kent
and Sussex counties, the Palmer Drought Severity Index indicates
that moderate drought conditions are in progress, and the Crop
Measure Index indicates drought conditions, with severe water
shortages for non-irrigated crops.
The Center for Climatic Research, located in the University's
Department of Geography, brings together scientists from across the campus
for interdisciplinary projects in basic and applied climatology. Research
currently under way ranges from studies concerning the association between
human health and global climate change to detailed investigations of the
climate of the northeast United States.