Monthly Climatological Summary
Norman 3SE, Cleveland Co., OK (Lat 35^10'57"N, Lon 97^25'27"W, elev 1130)
April 2001
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Temperature Precipitation Snow AM PM
Max Min Water Snow Depth Wx Wx
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01 69.1 35.4 .00 0.0 0 BKN BKN
02 78.8 59.4 .00 0.0 0 BKN BKN
03 84.7 63.3 .00 0.0 0 BKN BKN
04 84.2 62.8 T 0.0 0 -DZ FG BKN
05 83.3 65.8 T 0.0 0 BKN -DZ
06 80.8 67.5 T 0.0 0 OVC -SHRA
07 80.8 57.0 .00 0.0 0 OVC SKC
08 82.8 63.5 .00 0.0 0 BKN BKN
09 85.8 64.2 .00 0.0 0 BKN BKN
10 80.1 67.8 .01 0.0 0 OVC -TSRA
11 73.6 53.2 .70 0.0 0 +TSRA BLDU
12 70.5 42.1 .00 0.0 0 BKN BKN
13 76.6 44.6 .00 0.0 0 BKN BKN
14 67.5 58.3 .38 0.0 0 +TSRA OVC
15 74.1 55.6 .00 0.0 0 SKC FEW
16 72.1 46.6 .00 0.0 0 BKN BKN
17 58.6 38.5 .00 0.0 0 BKN SKC
18 66.7 34.5 .00 0.0 0 BKN BKN
19 74.5 52.0 .00 0.0 0 BKN BKN
20 79.5 64.9 .00 0.0 0 OVC OVC
21 77.9 67.6 .00 0.0 0 OVC OVC
22 80.1 63.0 .05 0.0 0 OVC TSRA
23 66.9 46.4 .00 0.0 0 FEW FEW
24 71.4 39.9 .00 0.0 0 SKC SKC
25 79.3 46.9 .00 0.0 0 SKC SKC
26 82.2 52.5 .00 0.0 0 SKC SKC
27 79.5 53.4 .00 0.0 0 SKC FEW
28 80.1 50.0 .00 0.0 0 SKC SCT
29 80.8 53.2 .00 0.0 0 SKC SCT
30 81.1 56.5 T 0.0 0 BKN -SHRA
KEY TO AM/PM WX: SKC - sky clear, FEW - few clouds, SCT -
partly cloudy, BKN - mostly cloudy, OVC - overcast, SHRA -
rain shower, TSRA - thunderstorm with rain, DZ - drizzle,
FG - fog, BLDU - blowing dust
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Means and Totals for March 2001
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Average Maximum Temperature: 76.8
Average Minimum Temperature: 54.2
Mean Temperature: 65.5
Maximum Temperature: 85.8 (4-09-01)
Minimum Temperature: 34.5 (4-18-01)
Days with max temperature 90.0F+: 0 Year: 0
Days with max temperature <32.0F: 0 Year: 3
Days with min temperature <32.0F: 0 Year: 39
Days with min temperature <0.0F: 0 Year: 0
Precipitation: 1.14 Year: 7.04
Greatest one-day precipitation: .70 (4-11-01)
Snowfall: 0.0 Year: 1.5
Greatest one-day snowfall: 0.0
Maximum snow depth at midnight: 0
Days with measureable pcpn: 4 Year: 27
Days with pcpn 1.00"+: 0 Year: 1
Days with measureable snowfall: 0 Year: 1
Days with snowfall 1"+: 0 Year: 1
Days with glaze ice: 0 Year: 5
Days with damaging wind: 3 Year: 5
Days with hail: 0 Year: 1
Days with thunderstorms: 4 Year: 11
Days with fog: 1 Year: 13
NOTICE: All temperatures are in degrees Fahrenheit and all precipitation values in inches. Snowfall totals denoted by an asterisk indicate hail.
Summary....A warm, windy, cloudy, and humid first half of the month helped central Oklahoma finish the month of Apr 2001 quite a bit warmer than average. Several powerful low pressure centers developed over Colorado during the month, which helped bring several bouts of gusty winds and humid Gulf of Mexico air to the area. Persistent cloud cover and warm air 1 to 2 miles above the ground tended to supress thunderstorm activity - which contributed to generally below average precipitation across the region. The only real rainfall of significance here occurred early on the 11th as high based thunderstorms moved over the area. These thunderstorms created their own "cool front" as the air underneath the thunderstorms cooled from all of the rain falling through it. As this "cool front" interacted with warmer air, new storms developed in southeastern Oklahoma which went on to produce five tornadoes. Later that day, gusty southwest winds kicked up a huge dust storm over much of the area. On the 14th, an isolated storm tracked from Blair to Purcell and dropped hail up to golf ball size. A line of thunderstorms went through the entire state on the 22nd. Golf ball sized hail was reported west of Norman, but no hail was observed here on the southeast part of the city. The last week of the month was very uneventful - with little in the way of clouds, wind, or humidity.
Turlock CA had 1.52 inches of rain in Apr 2001, and at 13.39 inches for the season they have surpassed the annual average of 13.25 inches. The Central Valley of CA had about as many days with thunderstorms as central Oklahoma did during the month - even my brother has seen more severe weather than I have this year! On Apr 7, my brother drove from Turlock to Fresno to watch the Grizzlies game. Near Atwater, he saw a funnel cloud that looked like "a little golf tee that was about half way to the ground". Minutes before the game was scheduled to start in Fresno, a massive hailstorm hit the stadium and lasted for about 40 minutes. Some of the hailstones were about the size of dimes. The game was cancelled although the weather was calm in Fresno for the rest of the evening.
My annual storm chase trip will be from May 14-22 so there will be some gaps in next month's report. Hopefully by this time next month I will have reclaimed bragging rights from my brother. :-)