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This Month's Daily Statistics
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SUBJECT: It was the warmest of times; it was the coldest of times
(sometimes during the same day)
Saint Cloud October 1999 weather summary
After a month of roller-coaster temperatures, October 1999 in St.
Cloud averaged nearly normal temperatures for the month. The average
temperature was within 0.2 degrees of normal. However, the daily record
tells a different story. The high temperature was more than 10 degrees off
the daily normal on 13 days during the month (9 above, 4 below). The low
temperature was more than 10 degrees off the daily normal on 8 days
(1 above, 7 below). This combination produced an October average
high temperature 1.5 degrees above normal and an average October low
2.0 degrees below normal.
The wild swings from warm to cold were produced by being
located near the jet stream while some awfully warm air stayed in the High
Plains and some very cold air drained out of northern Canada. The close
proximity allowed both types of air into Minnesota during the month.
The very dry conditions (.85 inch below normal; only .46 of rainfall
until October 29) also helped to create extremes. Dry air has a weaker
"greenhouse effect" than moist air since water vapor absorbs some of the sun's
warmth on the way to the ground during the day. At night, water vapor also
absorbs some of the outgoing Earth's radiation and sends it back. So, air with
less moisture will tend to have more extremes (warmer daytime highs, colder
nighttime lows), much like a desert climate.
While the normal October daily temperature range (difference
between high and low temperatures) is 23 degrees, October 1999 had 14 days
with at least a 30 degree sprea, six of which had a spread of at least
35 degrees. The wildest day was on the 9th with a morning low of 37,
followed by an afternoon high of 79.
SUMMARY FOR OCTOBER 1999 OCT 1999 NORMAL
TEMPERATURE
Average high temperature (F) 58.9 57.4
Average low temperature (F) 32.4 34.4
Average temperature (F) 45.7 45.9
Warmest high for this month (F) 77 on the 7th
Coolest high for this month (F) 45 on the 1st (broke record; see below)
Mildest low for this month (F) 77 on the 7th
Coldest low for this month (F) 18 on the 24th
Record temperatures (F):
Daily coldest high: 45 on the 1st (old record: 46 in 1944)
PRECIPITATION (in)
October 1.36 2.21
Greatest in 24 hours (Oct 1999) 0.78 on the 29th
