Monthly Climatological Summary
Norman 3SE, Cleveland Co., OK (Lat 35^10'57"N, Lon 97^25'27"W, elev 1130)
April 2002
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Temperature Precipitation Snow AM PM
Max Min Water Snow Depth Wx Wx
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01 76.8 45.5 .00 0.0 0 SKC FEW
02 69.6 45.9 .00 0.0 0 OVC OVC
03 51.1 32.4 .00 0.0 0 SCT SCT
04 62.8 34.2 .00 0.0 0 SKC SCT
05 66.2 37.4 .00 0.0 0 SCT OVC
06 57.0 47.1 .27 0.0 0 -RA TSRA
07 55.8 47.7 1.31 0.0 0 +TSRA +TSRA
08 62.4 50.2 .01 0.0 0 OVC -RA
09 69.8 46.9 .00 0.0 0 SKC SCT
10 73.8 47.8 .00 0.0 0 SCT SCT
11 77.7 55.9 .00 0.0 0 BKN SCT
12 71.6 55.8 .25 0.0 0 TSRA SCT
13 71.1 58.3 1.00 0.0 0 +TSRA SCT
14 79.7 56.1 .00 0.0 0 FG SCT
15 83.1 63.1 .00 0.0 0 SCT BKN
16 77.4 67.6 .03 0.0 0 -RA SCT
17 85.3 68.4 .00 0.0 0 BKN BKN
18 81.9 67.6 .00 0.0 0 OVC OVC
19 80.2 57.0 .01 0.0 0 OVC -RA
20 76.3 56.8 .04 0.0 0 -DZ FG -TSRA
21 71.4 53.1 .02 0.0 0 -RA BKN
22 76.6 44.6 .00 0.0 0 SCT SCT
23 79.0 60.4 .00 0.0 0 OVC BKN
24 80.2 56.1 .00 0.0 0 SCT SCT
25 66.9 47.5 .44 0.0 0 OVC RA
26 52.2 47.7 .14 0.0 0 -DZ -DZ FG
27 81.1 49.8 .03 0.0 0 -TSRA FG SCT
28 73.8 54.9 .00 0.0 0 BKN BKN
29 80.6 53.8 .00 0.0 0 OVC OVC
30 87.8 62.4 .00 0.0 0 OVC OVC
KEY TO AM/PM WX: SKC - sky clear, FEW - few clouds, SCT -
partly cloudy, BKN - mostly cloudy, OVC - overcast, RA -
rain, TSRA - thunderstorm with rain, FG - fog, DZ - drizzle.
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Means and Totals for April 2002
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Average Maximum Temperature: 72.6
Average Minimum Temperature: 52.4
Mean Temperature: 62.5
Maximum Temperature: 87.8 (4-30-02)
Minimum Temperature: 32.4 (4-03-02)
Days with max temperature 90.0F+: 0 Year: 0
Days with max temperature <32.0F: 0 Year: 4
Days with min temperature <32.0F: 0 Year: 46
Days with min temperature <0.0F: 0 Year: 0
Precipitation: 3.55 Year: 9.72
Greatest one-day precipitation: 1.31 (4-07-02)
Snowfall: 0.0 Year: 2.4
Greatest one-day snowfall: 0.0
Maximum snow depth at midnight: 0
Days with measureable pcpn: 12 Year: 30
Days with pcpn 1.00"+: 2 Year: 3
Days with measureable snowfall: 0 Year: 3
Days with snowfall 1"+: 0 Year: 1
Days with glaze ice: 0 Year: 2
Days with damaging wind: 0 Year: 2
Days with hail: 0 Year: 1
Days with thunderstorms: 6 Year: 11
Days with fog: 4 Year: 8
NOTICE: All temperatures are in degrees Fahrenheit and all precipitation values in inches. Snowfall totals denoted by an asterisk indicate hail.
Summary....April 2002 featured numerous days with rain and thunderstorms in Oklahoma, but very few days with severe weather. Even on days when winds in the upper levels of the atmosphere were favorable for severe storms to form, the potential for severe storms was repeatedly killed by factors such as too much cool air near the surface, too much hot air in the mid-levels of the atmosphere, and too much cloud cover. The only significant severe weather to occur in Oklahoma during the month did so from the 16th-18th. Several tornadoes touched down in Fort Worth and Arlington TX and in southern Oklahoma on the 16th. Numerous rotating thunderstorms developed in far western Oklahoma on the 17th, a few of which dropped baseball sized hail. A couple of these storms went on to produce tornadoes in northwestern Oklahoma into the early morning hours of the 18th.
Turlock CA tied for its second driest April the past 15 years, only receiving .07 inch of rain during the whole month. Turlock also had .07 inch in April 1989, and had just .01 inch in April 1992. Average rainfall for April is .86 inch. The 2001-02 season total is at 10.83 inches, and with two months to go for the rainy season, Turlock is not likely to reach its annual average of 13.25 inches (average rainfall for May and June combined is 1.02 inches).
Assuming by then that the atmosphere finally begins to realize that it's no longer March, I will begin my storm chase vacation on May 14. Hopefully the atmosphere will also have realized by then that Tornado Alley is in the Plains - and not from Missouri and Illinois to Pennsylvania and Maryland. What a strange tornado season this has been....