Dangerous Heat in the Central and Eastern U.S.; Severe Thunderstorms in the Plains to the Upper Midwest

A significant and dangerous heat wave will expand from the Central U.S. into the Eastern U.S and linger through much of the work week. Numerous daily record highs and warm lows are likely. Severe thunderstorms are possible from the southern Plains through the Upper Mississippi Valley. Fire weather concerns are expected to persist across the Four Corners region. Read More >

Hazardous Weather Conditions

Hazardous Weather Outlook

Current conditions at

Mason City Municipal Airport (KMCW)

Lat: 43.15°NLon: 93.33°WElev: 1188ft.

Fair

82°F

28°C

Humidity	63%
Wind Speed	S 16 G 23 mph
Barometer	29.84 in (1008.7 mb)
Dewpoint	68°F (20°C)
Visibility	10.00 mi
Heat Index	85°F (29°C)
Last update	22 Jun 9:53 pm CDT

More Information:

Local Forecast Office More Local Wx 3 Day History Hourly Weather Forecast

Extended Forecast for

Grafton IA

Tonight
Low: 75 °F
Increasing
Clouds and
Breezy
Monday
High: 83 °F
Chance
T-storms then
Showers
Likely
Monday Night
Low: 63 °F
Chance
T-storms then
Showers
Likely
Tuesday
High: 76 °F
Showers
Likely
Tuesday Night
Low: 64 °F
Showers
Likely then
Showers
Wednesday
High: 85 °F
Showers then
T-storms
Wednesday Night
Low: 67 °F
Showers
Thursday
High: 83 °F
Showers
Likely
Thursday Night
Low: 63 °F
Showers
Likely

Detailed Forecast

Tonight

Increasing clouds, with a low around 75. Breezy, with a south southwest wind 15 to 18 mph, with gusts as high as 31 mph.

Monday

A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1pm. Partly sunny, with a high near 83. South southwest wind 10 to 15 mph becoming northwest in the afternoon. Winds could gust as high as 23 mph. Chance of precipitation is 70%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

Monday Night

A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 2am. Increasing clouds, with a low around 63. North northeast wind 5 to 8 mph. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

Tuesday

Showers likely, with thunderstorms also possible after 10am. Mostly cloudy, with a high near 76. Northeast wind around 8 mph. Chance of precipitation is 70%. New rainfall amounts between a quarter and half of an inch possible.

Tuesday Night

Showers and possibly a thunderstorm. Low around 64. East wind around 6 mph. Chance of precipitation is 90%. New rainfall amounts between a quarter and half of an inch possible.

Wednesday

Showers and possibly a thunderstorm. High near 85. Chance of precipitation is 80%. New rainfall amounts between a quarter and half of an inch possible.

Wednesday Night

Showers and possibly a thunderstorm. Low around 67. Chance of precipitation is 80%.

Thursday

Showers likely and possibly a thunderstorm. Partly sunny, with a high near 83. Chance of precipitation is 70%.

Thursday Night

Showers likely and possibly a thunderstorm before 1am, then a chance of showers and thunderstorms after 1am. Mostly cloudy, with a low around 63. Chance of precipitation is 60%.

Friday

A 30 percent chance of showers after 1pm. Mostly sunny, with a high near 84.

Friday Night

A 30 percent chance of showers and thunderstorms. Partly cloudy, with a low around 65.

Saturday

A 30 percent chance of showers and thunderstorms. Mostly sunny, with a high near 88.

Saturday Night

Showers and thunderstorms likely. Partly cloudy, with a low around 69. Chance of precipitation is 60%.

Sunday

A 40 percent chance of showers and thunderstorms. Partly sunny, with a high near 87.