Cool temps continuing in July
Send a link to a friend
[JULY 12, 2004]
June temperatures averaged 70 degrees, 1.9 degrees below normal --
the 30th coldest June since 1895 -- and now July is following this
same pattern, with temperatures for the first nine days of July
averaging 2.4 degrees below normal," said
Jim Angel, state climatologist with the
Illinois State Water Survey,
a division of the Illinois Department of Natural Resources.
Since April 1, there have been 1,462
growing degree-days statewide compared with 1,440 such days normally
during this period. Growing degree-days, based on the number of days
with temperatures above a 50-degree threshold, are used to estimate
the rate of growth rate of crops.
Temperature extremes last month ranged
from 96 degrees at Hutsonville on June 12 to 40 degrees at Mount
Carroll on June 26. That's quite a jump but no surprise. The first
18 days of June were 2.2 degrees above normal, while the last 12
days were 8 degrees below normal. The last 12 days were the second
coldest end of June since 1900, beat only by June 19-30, 1902, which
was 10.3 degrees below normal.
June rainfall throughout Illinois was
87 percent of normal: 3.57 inches. Joliet reported the heaviest
one-day total: 4.02 inches on June 12. Hoopeston reported the
heaviest monthly total: 9.23 inches. So far July has been wetter
than normal: 1.78 inches compared with 1.09 inches normally. As a
result, soil moisture in the top 6 inches is 75 percent to 150
percent of normal in most of the state. Southeastern Illinois is the
only dry area, with the soil moisture site at Olney reporting just
under 50 percent of normal in this top soil layer as of July 6, the
last day surveyed.
[to top of second column in
The National Weather Service called for
above normal temperatures and precipitation this week, followed by
cooler, drier conditions. "This means that July precipitation could
end up being at or above normal with temperatures at or below
normal," Angel said.
"Historically, there is a weak positive correlation between July and
August temperatures (for example, a cool August is somewhat more
likely to follow a cool July) but almost no correlation between July
and August rainfall. In fact, last year August was very dry after a
wet July," he said.
State Water Survey news release]