Monthly Climatological Summary
Norman 3SE, Cleveland Co., OK (Lat 35^10'57"N, Lon 97^25'27"W, elev 1130)
May 2003
------------------------------------------------------------------
Temperature Precipitation Snow AM PM
Max Min Water Snow Depth Wx Wx
------------------------------------------------------------------
01 75.6 59.9 .00 0.0 0 BKN OVC
02 79.2 57.0 .00 0.0 0 BKN BKN
03 82.8 56.8 .00 0.0 0 OVC BKN
04 92.3 65.8 .00 0.0 0 BKN FEW
05 90.0 51.8 .00 0.0 0 SKC FEW
06 88.3 62.4 .00 0.0 0 BKN BKN
07 84.2 53.8 T 0.0 0 SCT -SHRA
08 88.0 71.8 .03 0.0 0 -TSRA TS
09 93.7 70.9 T 0.0 0 SCT -TSRA
10 89.2 62.8 .03 0.0 0 BKN TSRA
11 75.2 48.7 .00 0.0 0 SKC BKN
12 82.6 48.4 .00 0.0 0 SKC BKN
13 84.6 64.0 T 0.0 0 OVC -SHRA
14 83.3 67.5 .02 0.0 0 -TSRA BKN
15 84.4 64.2 .00 0.0 0 FG OVC
16 81.0 62.1 .09 0.0 0 TSRA -SHRA
17 74.8 59.5 T 0.0 0 -DZ BKN
18 85.6 56.7 .00 0.0 0 FG SCT
19 92.5 58.1 .52 0.0 0 SCT +TSRA
20 62.2 54.5 .49 0.0 0 +TSRA OVC
21 RA
22
23 TSRA
24 87.1 TSRA
25
26 53.1 (.18)
27 .00 0.0 0 SCT SCT
28 88.7 52.7 .00 0.0 0 SKC SCT
29 93.4 61.9 .00 0.0 0 SKC FEW
30 101.8 70.9 .00 0.0 0 SCT SCT
31 82.2 64.6 .00 0.0 0 BKN SCT
KEY TO AM/PM WX: SKC - sky clear, FEW - few clouds, SCT -
partly cloudy, BKN - mostly cloudy, OVC - overcast, RA -
rain, SHRA - rain shower, TS - thunderstorm, TSRA - thunderstorm
with rain, DZ - drizzle, FG - fog.
------------------------------------------------------------------
Means and Totals for May 2003
------------------------------------------------------------------
Average Maximum Temperature: 84.9
Average Minimum Temperature: 60.0
Mean Temperature: 72.5
Maximum Temperature: 101.8 (5-30-03)
Minimum Temperature: 48.4 (5-12-03)
Days with max temperature 90.0F+: 6 Year: 6
Days with max temperature <32.0F: 0 Year: 4
Days with min temperature <32.0F: 0 Year: 51
Days with min temperature <0.0F: 0 Year: 0
Precipitation: 1.36 Year: 7.82
Greatest one-day precipitation: .52 (5-19-03)
Snowfall: 0.0 Year: 5.0
Greatest one-day snowfall: 0.0
Maximum snow depth at midnight: 0
Days with measureable pcpn: 9 Year: 34
Days with pcpn 1.00"+: 0 Year: 1
Days with measureable snowfall: 0 Year: 4
Days with snowfall 1"+: 0 Year: 2
Days with glaze ice: 0 Year: 5
Days with damaging wind: 1 Year: 2
Days with hail: 0 Year: 4
Days with thunderstorms: 9 Year: 21
Days with fog: 2 Year: 10
NOTICE: All temperatures are in degrees Fahrenheit and all precipitation values in inches. Snowfall totals denoted by an asterisk indicate hail.
Summary....May 2003 will be forever remembered in central Oklahoma as the month the Oklahoma City area was hit by tornadoes on consecutive days. What may be overlooked is how some parts of the state hardly received any rain for most of the month. Despite all of the severe weather around the state in late April through mid May, my location somehow only managed to receive just .20 inch of rain between Apr 20 and May 18. Relief from the dry spell finally arrived on May 19-20, as thunderstorms repeatedly passed overhead following a cold frontal passage and dropped 1.01 inches of rain. Haze and smoke significantly reduced visibility across the region throughout the first two weeks of the month, as southerly winds fed a humid, smoke filled airmass from the southern Gulf of Mexico into the area. A northwesterly flow aloft took hold over the region after the 20th, bringing clearer, drier airmasses into the region. Thanks to this northwest flow, conditions through the end of the month were mostly cool and dry, although things got quite warm at the end of the month. Our high of 101.8F on the 30th was the first time the temperature exceeded 100F here since Aug 9, 2001.
STORM CHASE NOTES FOR MAY 2003.....
May 4.....Intercepted storm near McAlester OK. winds were out of the north when I was in McAlester, but a few miles up the road in Alderson I noticed the winds were out of the south. Shortly thereafter, railroad cars were reportedly blown off the tracks in Alderson. Got into some dime sized hail in Hartshorne, then tried keeping up with the storm as it raced through the hilly, forested terrain of southeastern Oklahoma. Storm got way ahead of me during this time and I was never able to catch up with it again.
May 8.....Heard report of tornado going through Moore as I was getting off work, and tried to catch up with it as it raced east of the Oklahoma City area. Even though I was 9 miles away, I could not even see the storm producing the tornado due to the horrible visibility, and could not keep up with the storm due to its fast movement.
May 15....Got a late start and ended up missing the tornadoes in the Texas and Oklahoma panhandles. Had trouble deciding whether or not to go after the existing storms in the Oklahoma panhandle or new storms trying to develop southeast of Amarillo TX, but in the end made a stab at the existing storms in the Oklahoma panhandle. Storms had weakened by the time I got there.
We called off our storm chase vacation this year. My chase partners came to Norman to pick me up on the 19th, and we drove to Amarillo TX the next day to get in position for a possible chase the day after that. We then realized that conditions would not be conducive for thunderstorms with sustained rotation or tornadoes for up to a week, so we ended up going home. Things looked so bad I ended up driving to Turlock CA for a couple of days - no thunderstorms there but it was a bit on the warm side (98F on the 23rd). Turlock had not received any rain in almost three weeks, and there was already .02 inch worth of bugs and dust in the rain gauge when I arrived on the 22nd. Turlock received .78 inch of rain at the beginning of the month, which brought the season rainfall total to 12.02 inches.