Forecast Information
Dated: 353 PM CDT THU JUL 29 2010
Expires: 430 AM CDT FRI JUL 30 2010
Includes the Counties: - Lyon
- Sioux
- Rock
- Minnehaha
- Lincoln
Includes the Cities: - Rock Rapids
- George
- Inwood
-
Larchwood
- Orange City
- Sioux Center
- Luverne
- Sioux Falls
-
Canton
- Lennox
- Tea
- Harrisburg
National Radar Composite
US 1-Day Observed Precipitation
National Ultrviolet Index (UVI)
Description of ICAO "KFSD"
- KFSD is at: Sioux Falls, Foss Field
- In the state of: (SD)
- In the country of United States (US)
- Station Latitude = 43.58N (decimal)
- Station Longitude = 96.75W (decimal)
- Station Elevation = 435 (meters)
- Time Zone = Central Daylight Time (CDT)
- Time Zone Offset from GMT = -5* (hours)
* Including Daylight Saving Time
The International Civil Aviation Organization (ICAO), an agency of the United Nations, codifies the principles and techniques of international air navigation.
The ICAO Code is a 4-letter airport code used to determin current conditions at that location at the time of request.
Current Conditions
Rain
Temp: 65°F
Humidity:
90%
Wind Speed:
SE 8.1 MPH (7 KT)
Barometer:
30.13 in.
Dewpoint:
62°F
Heat Index:
65°F
Wind Chill:
65°F
Updated: 4:56 PM CDT THU JUL 29 2010
Tonight
- Jul 29 2010 Chance Of T-Storm / Lo: 69°F / Pop: 80%

Mostly cloudy. Chance of thunderstorms in the evening...Then widespread thunderstorms after midnight. Some thunderstorms May produce heavy rainfall. Lows in the upper 60s. Southeast winds 5 to 15 mph. Chance of rain 80 percent.
Moon Phase: Waning Gibbous Moon
Sunset: 8:52 PM CDT
Dusk: 9:25 PM CDT
Friday
- Jul 30 2010 Chance Of T-Storm / Hi: 81°F / Pop: 50%

Mostly cloudy with chance of thunderstorms mainly in the morning...Then partly cloudy. Highs in the lower 80s. South winds 5 to 10 mph. Chance of rain 50 percent.
Dawn: 5:41 AM CDT
Sunrise: 6:14 AM CDT
Friday Night
- Jul 30 2010 Partly Cloudy / Lo: 65°F

Partly cloudy. Lows in the mid 60s. Southeast winds around 5 mph in the evening becoming light and variable.
Moon Phase: Waning Gibbous Moon
Sunset: 8:51 PM CDT
Dusk: 9:24 PM CDT
Saturday
- Jul 31 2010 Partly Cloudy / Hi: 89°F

Partly cloudy. Highs in the upper 80s. South winds 5 to 10 mph.
Dawn: 5:42 AM CDT
Sunrise: 6:15 AM CDT
Saturday Night
- Jul 31 2010 Partly Cloudy / Lo: 69°F

Partly cloudy. Lows in the upper 60s. Southeast winds 5 to 10 mph.
Moon Phase: Waning Gibbous Moon
Sunset: 8:50 PM CDT
Dusk: 9:22 PM CDT
Sunday
- Aug 01 2010 Chance Of T-Storm / Hi: 89°F / Pop: 20%

Partly cloudy. A 20 percent chance of thunderstorms in the afternoon. Highs in the upper 80s.
Dawn: 5:43 AM CDT
Sunrise: 6:16 AM CDT
Sunday Night
- Aug 01 2010 Chance Of T-Storm / Lo: 69°F / Pop: 50%

Mostly cloudy with a 50 percent chance of thunderstorms. Lows in the upper 60s.
Moon Phase: Last Quarter Moon
Sunset: 8:49 PM CDT
Dusk: 9:21 PM CDT
Monday
- Aug 02 2010 Chance Of T-Storm / Hi: 85°F / Pop: 40%

Partly sunny with a 40 percent chance of thunderstorms. Highs in the mid 80s.
Dawn: 5:44 AM CDT
Sunrise: 6:17 AM CDT
Monday Night
- Aug 02 2010 Chance Of T-Storm / Lo: 65°F / Pop: 20%

Mostly cloudy with a 20 percent chance of thunderstorms in the evening...Then partly cloudy after midnight. Lows in the mid 60s.
Moon Phase: Waning Crescent Moon
Sunset: 8:47 PM CDT
Dusk: 9:20 PM CDT
Tuesday
- Aug 03 2010 Partly Cloudy / Hi: 81°F

Partly cloudy. Highs in the lower 80s.
Dawn: 5:46 AM CDT
Sunrise: 6:18 AM CDT
Tuesday Night
- Aug 03 2010 Chance Of T-Storm / Hi: 81°F / Lo: 65°F / Pop: 20%

Partly cloudy with a 20 percent chance of thunderstorms. Lows in the mid 60s. Highs in the lower 80s.
Moon Phase: Waning Crescent Moon
Sunset: 8:46 PM CDT
Dusk: 9:18 PM CDT
Wednesday
- Aug 04 2010 Chance Of T-Storm / Hi: 81°F / Lo: 65°F / Pop: 20%

Partly cloudy with a 20 percent chance of thunderstorms. Lows in the mid 60s. Highs in the lower 80s.
Dawn: 5:47 AM CDT
Sunrise: 6:19 AM CDT
Wednesday Night
- Aug 04 2010 Chance Of T-Storm / Lo: 65°F / Pop: 30%

Mostly cloudy with a 30 percent chance of thunderstorms. Lows in the mid 60s.
Moon Phase: Waning Crescent Moon
Sunset: 8:45 PM CDT
Dusk: 9:17 PM CDT
Thursday
- Aug 05 2010 Chance Of T-Storm / Hi: 85°F / Pop: 20%

Partly cloudy with a 20 percent chance of thunderstorms. Highs in the mid 80s.
Dawn: 5:48 AM CDT
Sunrise: 6:20 AM CDT
Sun & Moon Information Definitions
Moon Phase: The phases of the Moon are related to (actually, caused by) the relative positions of the Moon and Sun in the sky. For example, New Moon occurs when the Sun and Moon are quite close together in the sky. Full Moon occurs when the Sun and Moon are at nearly opposite positions in the sky - which is why a Full Moon rises about the time of sunset, and sets about the time of sunrise, for most places on Earth.
Waning Gibbous Moon: The Moon appears to be more than one-half but not fully illuminated by direct sunlight. The fraction of the Moons disk that is illuminated is decreasing.
Twilight: Also known as "Dawn" preceding Sunrise and "Dusk" following Sunset. There are three kinds of twilight defined: civil twilight, nautical twilight, and astronomical twilight. For computational purposes, civil twilight begins before sunrise and ends after sunset when the geometric zenith distance of the center of the Sun is 96 degrees - 6 degrees below a horizontal plane. The corresponding solar zenith distances for nautical and astronomical twilight are 102 and 108 degrees, respectively. That is, at the dark limit of nautical twilight, the center of the Sun is geometrically 12 degrees below a horizontal plane; and at the dark limit of astronomical twilight, the center of the Sun is geometrically 18 degrees below a horizontal plane.
Sunrise and sunset: For computational purposes, sunrise or sunset is defined to occur when the geometric zenith distance of center of the Sun is 90.8333 degrees. That is, the center of the Sun is geometrically 50 arcminutes below a horizontal plane. For an observer at sea level with a level, unobstructed horizon, under average atmospheric conditions, the upper limb of the Sun will then appear to be tangent to the horizon. The 50-arcminute geometric depression of the Sun's center used for the computations is obtained by adding the average apparent radius of the Sun (16 arcminutes) to the average amount of atmospheric refraction at the horizon (34 arcminutes).
Accuracy of rise/set computations: The times of rise and set phenomena cannot be precisely computed, because, in practice, the actual times depend on unpredictable atmospheric conditions that affect the amount of refraction at the horizon. Thus, even under ideal conditions (e.g., a clear sky at sea) the times computed for rise or set may be in error by a minute or more. Local topography (e.g., mountains on the horizon) and the height of the observer can affect the times of rise or set even more. It is not practical to attempt to include such effects in routine rise/set computations.