National Weather Service United States Department of Commerce

Severe Thunderstorms and Flooding from the Southern Plains to the Great Lakes; Record Heat in the East

Widely scattered severe thunderstorms may produce damaging winds, hail, and flash flooding from the southern Plains into the lower Great Lakes. Elevated to locally critical fire weather conditions will persist across portions of the Southwest and Southern High Plains due to gusty winds and dry conditions. An early-season heatwave will challenge temperature records across the eastern U.S.. Read More >

KMAF Aviation Climatology

The following values are percent of occurrence of different flying weather conditions.

The data was derived from 31 years of data (1973-2004).

Skip marginal visual flight rule occurrence table.

Ceiling between 1000-3000 feet and/or Visibility between 3-5 miles (MVFR)
Hour Jan Feb Mar Apr May Jun July Aug Sep Oct Nov Dec Ann
1 am 7 % 6 % 6 % 4 % 4 % 1 % 1 % 2 % 4 % 5 % 5 % 5 % 4.2%
4 am 6 % 6 % 7 % 5 % 5 % 2 % 1 % 2 % 4 % 6 % 7 % 6 % 4.8%
7 am 6 % 7 % 10 % 7 % 9 % 3 % 2 % 1 % 5 % 8 % 8 % 7 % 6.1%
10 am 7 % 8 % 10 % 11% 12% 9 % 4 % 3 % 9 % 9 % 8 % 8 % 8.2%
1 pm 8 % 8 % 12 % 12% 16% 13% 8 % 7 % 14% 11% 10% 8 % 6.6%
4 pm 8 % 8 % 10 % 10% 12% 10% 7 % 7 % 12% 12% 9 % 6 % 8.7%
7 pm 9 % 9 % 8 % 7 % 7 % 5 % 4 % 3 % 9 % 9 % 8 % 8 % 7.2%
10 pm 8 % 8 % 7 % 4 % 5 % 2 % 2 % 2 % 5 % 5 % 7 % 7 % 5.2%

Skip instrument flight rule occurrence table.

Ceiling greater than or = 500 feet to less than 1000 feet and/or Visibility greater than or = to 1mile to less than 3 miles (IFR)
Hour Jan Feb Mar Apr May Jun July Aug Sep Oct Nov Dec Ann
1 am 3 % 3 % 2 % 1 % 1 % 0 % 0 % 0 % 2 % 2 % 3 % 3 % 1.7%
4 am 3 % 4 % 2 % 1 % 1 % 0 % 0 % 0 % 2 % 3 % 3 % 4 % 1.9%
7 am 4 % 5 % 3 % 1 % 1 % 1 % 1 % 1 % 3 % 4 % 5 % 4 % 2.8%
10 am 4 % 7 % 4 % 4 % 3 % 1 % 2 % 2 % 4 % 6 % 5 % 4 % 3.8%
1 pm 6 % 7 % 4 % 6 % 5 % 2 % 2 % 2 % 5 % 7 % 6 % 3 % 4.6%
4 pm 7 % 6 % 4 % 3 % 2 % 1 % 1 % 1 % 5 % 6 % 5 % 5 % 3.8%
7 pm 5 % 6 % 3 % 1 % 1 % 0 % 0 % 0 % 3 % 3 % 4 % 4 % 2.5%
10 pm 4 % 3 % 2 % 2 % 1 % 0 % 1 % 0 % 2 % 2 % 2 % 4 % 1.9%

Skip low instrument flight rule occurrence table.

Ceiling greater than or = to 200 feet to less than 500 feet and/or Visibility greater than or = to 1/2 mile to less than 1 mile (LIFR)
Hour Jan Feb Mar Apr May Jun July Aug Sep Oct Nov Dec Ann
1 am 4 % 2 % 1 % 0 % 0 % 0 % 0 % 0 % 0 % 0 % 2 % 2 % 0.9%
4 am 4 % 2 % 1 % 1 % 0 % 0 % 0 % 0 % 1 % 1 % 2 % 2 % 1.2%
7 am 4 % 3 % 2 % 1 % 1 % 0 % 0 % 0 % 2 % 2 % 3 % 2 % 1.7%
10 am 5 % 4 % 2 % 1 % 1 % 0 % 0 % 0 % 3 % 3 % 5 % 4 % 2.3%
1 pm 6 % 5 % 3 % 2 % 1 % 1 % 1 % 1 % 4 % 4 % 6 % 4 % 3.2%
4 pm 6 % 5 % 2 % 1 % 1 % 0 % 0 % 0 % 2 % 2 % 4 % 4 % 2.3%
7 pm 4 % 2 % 1 % 0 % 0 % 0 % 0 % 0 % 1 % 1 % 2 % 2 % 1.1%
10 pm 3 % 2 % 0 % 1 % 0 % 0 % 0 % 0 % 0 % 0 % 2 % 1 % 0.8%

Skip very low instrument flight rule occurrence table.

Ceiling less than 200 feet and/or Visibility less than 1/2 mile (VLIFR)
Hour Jan Feb Mar Apr May Jun July Aug Sep Oct Nov Dec Ann
1 am 1 % 1 % 1 % 0 % 0 % 0 % 0 % 0 % 0 % 0 % 1 % 1 % 0.4%
4 am 3 % 2 % 1 % 0 % 0 % 0 % 0 % 0 % 0 % 0 % 1 % 2 % 0.8%
7 am 4 % 2 % 1 % 0 % 0 % 0 % 0 % 0 % 0 % 1 % 2 % 3 % 1.1%
10 am 6 % 4 % 1 % 1 % 0 % 0 % 0 % 0 % 0 % 2 % 3 % 3 % 1.7%
1 pm 5 % 6 % 2 % 1 % 1 % 0 % 0 % 0 % 1 % 3 % 3 % 4 % 2.2%
4 pm 3 % 3 % 0 % 0 % 0 % 0 % 0 % 0 % 0 % 0 % 1 % 2 % 0.8%
7 pm 1 % 1 % 0 % 0 % 0 % 0 % 0 % 0 % 0 % 0 % 0 % 1 % 0.3%
10 pm 1 % 0 % 0 % 0 % 0 % 0 % 0 % 0 % 0 % 0 % 1 % 0 % 0.2%

Skip marginal visual flight ruleand below occurrence table.

Ceiling less than or = to 3000 feet and/or Visibility less than or = to 5 miles
Hour Jan Feb Mar Apr May Jun July Aug Sep Oct Nov Dec Ann
1 am 15% 12% 10% 5 % 5 % 0 % 0 % 0 % 0 % 0 % 1 % 1 % 0.4%
4 am 16% 14% 11% 0 % 6 % 0 % 0 % 0 % 0 % 0 % 1 % 2 % 0.8%
7 am 18% 17% 16% 0 % 11% 0 % 0 % 0 % 0 % 1 % 2 % 3 % 1.1%
10 am 22% 23% 17% 1 % 16% 0 % 0 % 0 % 0 % 2 % 3 % 3 % 1.7%
1 pm 25% 26% 21% 1 % 1 % 0 % 0 % 0 % 1 % 3 % 3 % 4 % 2.2%
4 pm 24% 22% 16% 0 % 0 % 0 % 0 % 0 % 0 % 0 % 1 % 2 % 0.8%
7 pm 19% 18% 12% 0 % 0 % 0 % 0 % 0 % 0 % 0 % 0 % 1 % 0.3%
10 pm 16% 13% 9 % 0 % 0 % 0 % 0 % 0 % 0 % 0 % 1 % 0 % 0.2%

Skip instrument flight rules and below occurrence table.

Ceiling less than 1000 feet and/or Visibility less than 3 miles
Hour Jan Feb Mar Apr May Jun July Aug Sep Oct Nov Dec Ann
1 am 8% 12% 4% 1 % 1 % 0 % 0 % 0 % 2 % 2 % 6 % 6 % 3.5%
4 am 10% 8% 4% 2 % 1 % 0 % 0 % 0 % 3 % 4 % 6 % 8 % 3.8%
7 am 12% 10% 6% 2 % 2 % 1 % 1 % 1 % 5 % 7 % 10% 9 % 5.5%
10 am 15% 15% 7% 6 % 4 % 1 % 2 % 2 % 7 % 11% 13% 11% 7.8%
1 pm 17% 18% 9% 9 % 7 % 3 % 3 % 3 % 10% 14% 15% 11% 9.9%
4 pm 16% 14% 6% 4 % 3 % 1 % 1 % 1 % 7 % 8 % 10% 11% 6.8%
7 pm 10% 9% 4% 1 % 1 % 0 % 0 % 0 % 4 % 4 % 6% 7 % 3.8%
10 pm 8% 5% 2 % 3 % 1 % 0 % 1 % 0 % 2 % 2 % 5% 5 % 2.8%

Skip low instrument flight rules and below occurrence table.

Ceiling less than 500 feet and/or Visibility less than 1 mile
Hour Jan Feb Mar Apr May Jun July Aug Sep Oct Nov Dec Ann
1 am 4 % 2 % 1 % 0 % 0 % 0 % 0 % 0 % 0 % 0 % 2 % 2 % 0.9%
4 am 4 % 2 % 1 % 1 % 0 % 0 % 0 % 0 % 1 % 1 % 2 % 2 % 1.2%
7 am 4 % 3 % 2 % 1 % 1 % 0 % 0 % 0 % 2 % 2 % 3 % 2 % 1.7%
10 am 5 % 4 % 2 % 1 % 1 % 0 % 0 % 0 % 3 % 3 % 5 % 4 % 2.3%
1 pm 6 % 5 % 3 % 2 % 1 % 1 % 1 % 1 % 4 % 4 % 6 % 4 % 3.2%
4 pm 6 % 5 % 2 % 1 % 1 % 0 % 0 % 0 % 2 % 2 % 4 % 4 % 2.3%
7 pm 4 % 2 % 1 % 0 % 0 % 0 % 0 % 0 % 1 % 1 % 2 % 2 % 1.1%
10 pm 3 % 2 % 0 % 1 % 0 % 0 % 0 % 0 % 0 % 0 % 2 % 1 % 0.8%

 

Ceiling less than 200 feet and/or Visibility less than 1/2 mile
Hour Jan Feb Mar Apr May Jun July Aug Sep Oct Nov Dec Ann
1 am 1 % 1 % 1 % 0 % 0 % 0 % 0 % 0 % 0 % 0 % 1 % 1 % 0.4%
4 am 3 % 2 % 1 % 0 % 0 % 0 % 0 % 0 % 0 % 0 % 1 % 2 % 0.8%
7 am 4 % 2 % 1 % 0 % 0 % 0 % 0 % 0 % 0 % 1 % 2 % 3 % 1.1%
10 am 6 % 4 % 1 % 1 % 0 % 0 % 0 % 0 % 0 % 2 % 3 % 3 % 1.7%
1 pm 5 % 6 % 2 % 1 % 1 % 0 % 0 % 0 % 1 % 3 % 3 % 4 % 2.2%
4 pm 3 % 3 % 0 % 0 % 0 % 0 % 0 % 0 % 0 % 0 % 1 % 2 % 0.8%
7 pm 1 % 1 % 0 % 0 % 0 % 0 % 0 % 0 % 0 % 0 % 0 % 1 % 0.3%
10 pm 1 % 0 % 0 % 0 % 0 % 0 % 0 % 0 % 0 % 0 % 1 % 0 % 0.2%