More on Our Wet July, 1997
Topic:  Preliminary July Climate Summary

I am not the only one who is happy to say goodbye and good 
riddance to July's weather.  In brief, it started out stormy
(windy with severe thunderstorms) and cold (near record cold
the first week), followed by ugly (cloudy) and wet (frequent
and excessive rainfall), then oppressive humidity (dew points 
above 75 degrees F) with abundant mosquitos and mold.  I was 
provoked to write the following cynical verse about summer: 

    Summertime isn't always so sublime. 
    Sometimes it's a crime. 
    Wet basements. Damaged pavements. Insurance claimants. 
    Saturated soil. Cars that boil. Food that spoils. 
    Broken trees. July freeze. Plant disease. 
    Running fans. Watering bans. Sweaty hands. 
    Too much heat. Cannot sleep. Feeling cheap. 
    Soccer rainout. Broken downspout. Many chores to count. 
    Downed wires. Irritable drivers. Patience that tires. 
    Forecasters mistakes. Hard to take. Give 'em a break. 

July was one of the wettest on record for many locations. The
preliminary data suggest it was the 7th wettest July for 
the state as a whole, averaging all reports.  In central
and east central Minnesota it was perhaps the wettest July
ever, with numerous reports of total rainfall in excess of
10 inches.  The following communites set rainfall records
for the month: Delano at 10.19 inches, Hutchinson at 9.33 
inches, Hastings at 13.51 inches, and Faribault with 8.71 
inches.  Many other locations recorded 10 inches or greater,
ranking second behind the two other wet Julys of 1987 and 
1972. The Twin Cities with 12.48 inches was second only to
17.9 inches recorded for July of 1987.

Climate Division mean July rainfall for 1997 and the associated
historical ranking for the period 1896-1997 (from preliminary
data through MCC)...

CD 4  5.37 inches, 8th wettest
CD 5  9.43 inches, wettest
CD 6  9.63 inches, wettest
CD 8  7.13 inches, 4th wettest
CD 9  8.20 inches, 2nd wettest

Other CDs were not ranked in the top 10 historically.

Rainfall intensity records were approached or exceeded as well,
with numerous storms around the state dumping over 2 inches per
hour and one storm (July 1st) in the Twin Cities exceeding 3 
inches per hour, which surpasses the 100 year return period 
for 1 hour intensity.  Some of these intense storms also 
delivered hail to western Minnesota counties, particularly 
Swift and Chippewa.

Rainfall frequency records we also broken.  Rosemount recorded 
20 days with measurable rainfall, MSP 17 days, La Crosse 17 days,
St Cloud 16 days, and Red Wing 15 days.  These all equalled or
exceeded the station record for most wet days in the month of July.

Lastly, several high dew point records were broken for numerous
communities around the state.  Dew points in the high 70s, and 
even 80 degrees F were common during the second half of the month.
Locally, the St Paul Climatological Observatory recorded 231 hours 
with dew points of 70 degrees F or greater during July.  The 
average annual number of hours with dew points this high is only 97.
Dew points of 75 degrees F or greater were recorded for 52 hours 
during the month, compared to an annual average for the Twin Cities
of only 10 hours.  No wonder everybody's air conditioning bills are
so high.  

Mark Seeley
Professor and Extension Climatologist
Department of Soil, Water, and Climate
University of Minnesota
St Paul, MN  55108

Ph.  (612) 625-4724
FAX  (612) 625-2208


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Last modified: August 1, 1997