Alton, Illinois Weather Conditions

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Current Conditions

  • 60°
  • Clear
  • Wind: Calm
  • Humidity: 91%
  • Visibility: 10.0 miles
  • Dew Point: 57°
  • Pressure: 29.96 in. 0

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Next 12 Hours

1  am
4  am
7  am
10  am
1  pm
Clear
Clear
Clear
Clear
Clear
Clear
Clear
Clear
Partly Cloudy
Partly Cloudy
64°
61°
57°
73°
84°
Forecast data from the National Digital Forecast Database.

5 Day Forecast

  • Tuesday
  • Partly Cloudy
  • High: 84 °
  • Low: 55 °
  • Partly Cloudy
  • Wednesday
  • Chance of a Thunderstorm
  • High: 84 °
  • Low: 66 °
  • Chance of a Thunderstorm
  • Thursday
  • Thunderstorm
  • High: 82 °
  • Low: 57 °
  • T-Storms
  • Friday
  • Chance of Rain
  • High: 73 °
  • Low: 43 °
  • Chance of Rain
  • Saturday
  • Partly Cloudy
  • High: 72 °
  • Low: 52 °
  • Partly Cloudy

Forecast for Alton, Illinois

Updated: 10:00 PM CDT on September 29, 2014

  • Tuesday

    Clear in the morning, then partly cloudy. High of 84F. Winds less than 5 mph.

  • Tuesday Night

    Partly cloudy in the evening, then clear. Low of 55F. Winds from the ESE at 5 to 10 mph.

  • Wednesday

    Clear in the morning, then partly cloudy. High of 84F. Winds from the SSE at 5 to 10 mph. Chance of rain 20%.

  • Wednesday Night

    Partly cloudy with a chance of a thunderstorm and a chance of rain, then thunderstorms and rain showers after midnight. Low of 66F. Winds from the SSE at 5 to 10 mph. Chance of rain 60% with rainfall amounts near 0.2 in. possible.

  • Thursday

    Overcast with thunderstorms and rain showers. High of 82F. Winds from the South at 5 to 10 mph. Chance of rain 70% with rainfall amounts near 0.4 in. possible.

  • Thursday Night

    Overcast with thunderstorms, then a chance of a thunderstorm and rain after midnight. Fog overnight. Low of 57F. Winds from the SW at 5 to 10 mph. Chance of rain 70% with rainfall amounts near 1.2 in. possible.

  • Friday

    Partly cloudy with a chance of rain. High of 73F. Breezy. Winds from the WNW at 15 to 20 mph. Chance of rain 30%.

  • Friday Night

    Clear in the evening, then partly cloudy. Low of 43F. Winds from the WNW at 5 to 15 mph.

  • Saturday

    Partly cloudy. High of 72F. Winds from the SW at 5 to 10 mph.

  • Saturday Night

    Clear. Low of 52F. Winds from the SSW at 5 to 15 mph.

  • Sunday

    Clear. High of 75F. Winds from the WSW at 5 to 10 mph.

  • Sunday Night

    Partly cloudy. Fog overnight. Low of 57F. Winds from the West at 5 to 10 mph.

  • Monday

    Partly cloudy. High of 75F. Winds less than 5 mph.

  • Monday Night

    Partly cloudy. Fog overnight. Low of 46F. Winds less than 5 mph.

  • Tuesday

    Clear. High of 73F. Winds from the SSW at 5 to 10 mph shifting to the WNW in the afternoon.

  • Tuesday Night

    Clear. Fog overnight. Low of 46F. Winds less than 5 mph.

  • Wednesday

    Partly cloudy with a chance of a thunderstorm. Fog early. High of 73F. Winds less than 5 mph. Chance of rain 40%.

  • Wednesday Night

    Partly cloudy with a chance of a thunderstorm. Fog overnight. Low of 50F. Winds from the SSW at 5 to 10 mph. Chance of rain 40%.

  • Thursday

    Clear. High of 70F. Winds from the SW at 5 to 10 mph.

  • Thursday Night

    Clear. Low of 50F. Winds less than 5 mph.

  • Friday

    Clear. High of 64F. Winds less than 5 mph.

  • Friday Night

    Clear. Fog overnight. Low of 50F. Winds less than 5 mph.

Personal Weather Stations

Personal Weather Stations [Add your weather station!]

Location: Alton, IL

Updated: 12:54 AM CDT

Temperature: 60.8 °F Dew Point: 59 °F Humidity: 95% Wind: Calm Pressure: 29.40 in Hourly Precipitation: 0.00 in Graphs

Location: Alton - Beacon, Alton, IL

Updated: 12:54 AM CDT

Temperature: 65.4 °F Dew Point: 61 °F Humidity: 85% Wind: Calm Pressure: 29.92 in Hourly Precipitation: 0.00 in Graphs

Location: Alton - Christian Hill Area, Alton, IL

Updated: 12:50 AM CDT

Temperature: 67.6 °F Dew Point: 59 °F Humidity: 74% Wind: Calm Pressure: 29.90 in Hourly Precipitation: 0.00 in Graphs

Location: MesoWest US-67 @ Clark Bridge IL US ILDOT, Alton, IL

Updated: 12:25 AM CDT

Temperature: 62 °F Dew Point: 62 °F Humidity: 99% Wind: Calm Pressure: - Hourly Precipitation: 0.00 in Graphs

Location: Alton - Rock Gate Estates, Alton, IL

Updated: 12:54 AM CDT

Temperature: 61.8 °F Dew Point: 60 °F Humidity: 94% Wind: Calm Pressure: 29.96 in Hourly Precipitation: 0.00 in Graphs

Location: Milton Area - Oscar, Alton, IL

Updated: 12:44 AM CDT

Temperature: 60.7 °F Dew Point: 60 °F Humidity: 96% Wind: Calm Pressure: 29.89 in Hourly Precipitation: 0.00 in Graphs

Location: Brecht Ln, Godfrey, IL

Updated: 12:51 AM CDT

Temperature: 59.4 °F Dew Point: 58 °F Humidity: 95% Wind: Calm Pressure: 29.81 in Hourly Precipitation: - Graphs

Location: WEST ALTON, West Alton, MO

Updated: 12:50 AM CDT

Temperature: 62.2 °F Dew Point: - Humidity: - Wind: North at - Pressure: - Hourly Precipitation: - Graphs

Location: Godfrey River Aire Subdivision, Godfrey, IL

Updated: 12:54 AM CDT

Temperature: 59.1 °F Dew Point: 57 °F Humidity: 94% Wind: Calm Pressure: 29.89 in Hourly Precipitation: 0.00 in Graphs

Location: APRSWXNET East Alton IL US, Wood River, IL

Updated: 12:28 AM CDT

Temperature: 64 °F Dew Point: 59 °F Humidity: 83% Wind: Calm Pressure: 29.97 in Hourly Precipitation: 0.00 in Graphs

Location: Rosewood Heights, East Alton, IL

Updated: 12:54 AM CDT

Temperature: 63.2 °F Dew Point: 59 °F Humidity: 85% Wind: Calm Pressure: 29.89 in Hourly Precipitation: 0.00 in Graphs

Location: Foster Township, Alton, IL

Updated: 12:52 AM CDT

Temperature: 58.5 °F Dew Point: 58 °F Humidity: 98% Wind: Calm Pressure: 29.90 in Hourly Precipitation: - Graphs

Location: Jersey County along IL 111, Brighton, IL

Updated: 12:54 AM CDT

Temperature: 61.0 °F Dew Point: 54 °F Humidity: 78% Wind: Calm Pressure: 29.62 in Hourly Precipitation: 0.00 in Graphs

Location: Timber Ridge, Godfrey, IL

Updated: 12:50 AM CDT

Temperature: 57.9 °F Dew Point: 57 °F Humidity: 96% Wind: Calm Pressure: 29.93 in Hourly Precipitation: 0.00 in Graphs

Location: MesoWest NAMOK1 IL US UPR, Granite City, IL

Updated: 11:45 PM CDT

Temperature: 67 °F Dew Point: - Humidity: - Wind: Calm Pressure: - Hourly Precipitation: 0.00 in Graphs

Location: Grand Ave, Edwardsville, IL

Updated: 12:53 AM CDT

Temperature: 62.1 °F Dew Point: 60 °F Humidity: 94% Wind: Calm Pressure: 29.88 in Hourly Precipitation: 0.00 in Graphs

Location: Riverwood Place, Florissant, MO

Updated: 12:54 AM CDT

Temperature: 60.6 °F Dew Point: 59 °F Humidity: 94% Wind: Calm Pressure: 29.94 in Hourly Precipitation: 0.00 in Graphs

Location: Nickel Plate Trail, Edwardsville, IL

Updated: 12:50 AM CDT

Temperature: 61.6 °F Dew Point: 60 °F Humidity: 95% Wind: Calm Pressure: 29.92 in Hourly Precipitation: 0.00 in Graphs

Location: EAST GRANITE, Granite City, IL

Updated: 12:42 AM CDT

Temperature: 65.8 °F Dew Point: 62 °F Humidity: 87% Wind: Calm Pressure: 29.90 in Hourly Precipitation: - Graphs

Location: MesoWest SHPMAN IL US UPR, Shipman, IL

Updated: 12:05 AM CDT

Temperature: 61 °F Dew Point: - Humidity: - Wind: Calm Pressure: - Hourly Precipitation: 0.00 in Graphs

Location: Piasa, Piasa, IL

Updated: 12:42 AM CDT

Temperature: 61.9 °F Dew Point: 58 °F Humidity: 87% Wind: Calm Pressure: 29.89 in Hourly Precipitation: 0.00 in Graphs

Location: Barbarotto Compound, Maryville, IL

Updated: 12:54 AM CDT

Temperature: 61.4 °F Dew Point: 59 °F Humidity: 91% Wind: Calm Pressure: 29.85 in Hourly Precipitation: 0.00 in Graphs

Location: 1 Mile South of St. Louis Lambert Airport, Woodson Terrace, MO

Updated: 12:54 AM CDT

Temperature: 62.8 °F Dew Point: 60 °F Humidity: 89% Wind: Calm Pressure: 29.94 in Hourly Precipitation: 0.00 in Graphs

Location: Rolling Meadows Dr, Maryville, IL

Updated: 12:54 AM CDT

Temperature: 63.7 °F Dew Point: 57 °F Humidity: 79% Wind: Calm Pressure: 29.29 in Hourly Precipitation: 0.00 in Graphs

Location: Polestar Boating Center, St. Charles, MO

Updated: 12:54 AM CDT

Temperature: 65.2 °F Dew Point: 64 °F Humidity: 96% Wind: Calm Pressure: 29.99 in Hourly Precipitation: 0.00 in Graphs

Location: St. Ann, MO, St. Ann, MO

Updated: 12:41 AM CDT

Temperature: 61.0 °F Dew Point: 58 °F Humidity: 89% Wind: Calm Pressure: 29.87 in Hourly Precipitation: - Graphs

Location: Liberty Place, Troy, IL

Updated: 12:42 AM CDT

Temperature: 60.2 °F Dew Point: 58 °F Humidity: 92% Wind: Calm Pressure: 29.32 in Hourly Precipitation: 0.00 in Graphs

Location: Hamel, IL 55/140, Worden, IL

Updated: 12:54 AM CDT

Temperature: 58.1 °F Dew Point: 56 °F Humidity: 91% Wind: Calm Pressure: 28.46 in Hourly Precipitation: 0.00 in Graphs

Location: BLAIR STREET, St. Louis, MO

Updated: 12:50 AM CDT

Temperature: 69.8 °F Dew Point: - Humidity: 75% Wind: North at - Pressure: 29.43 in Hourly Precipitation: - Graphs

Location: MesoWest I -55/64/70 @ Poplar St Bridge IL US ILDOT, Fairmont City, IL

Updated: 12:25 AM CDT

Temperature: 67 °F Dew Point: 63 °F Humidity: 87% Wind: Calm Pressure: - Hourly Precipitation: 0.00 in Graphs

MSN Maps of:

Temp: Dew Point: Humidity Wind Pressure Hr Precip -

NWS Forecaster Discussion




Area forecast discussion...updated aviation 
National Weather Service St Louis MO 
1151 PM CDT Mon Sep 29 2014 


Update: 
issued at 915 PM CDT Mon Sep 29 2014 


Despite a cold front dropping down and entering the far northern 
portions of the forecast area (northeast MO and west- central il) 
late tonight, it should move thru dry. However, area of low 
stratus has developed behind the front in northern Illinois and based on 
relationship to front, is expected to affect some portions of the 
far northern forecast area towards daybreak and shortly after 
sunrise. Things a bit muddier after that, but should see the 
southward stratus advance slow and halt during the morning with 
the stratus probably scattering during the day. Have adjusted 
cloud forecast accordingly, with areas to the south of the front, 
including areas near the I-70 corridor and to the south of there 
remaining clear. 


Otherwise, remainder of the forecast on track with no adjustments 
needed to temps or rain chances. 


Tes 


&& 


Short term: (through late tonight) 
issued at 315 PM CDT Mon Sep 29 2014 


Another tranquil dry night on tap for the area. Weather features 
we have been discussing the last few days remain the same. The 
east-west cold front currently stretching across southern Wisconsin 
into South Dakota will drop into northern MO and central Illinois 
overnight in response to the digging trof moving into the Great 
Lakes and downstream amplification. This front should reach near a 
Columbia-St. Louis-Effingham line by 12z. Weak high pressure and 
light winds will continue ahead of the front for a good part of 
the night resulting in another round of overnight lows primarily 
in the 50s. 


Glass 


Long term: (tuesday through next monday) 
issued at 315 PM CDT Mon Sep 29 2014 


Not many changes needed to the previous forecast as it continues 
to blend well with the latest thoughts and nwp guidance. Still 
looking at a tranquil dry period Tuesday and Tuesday night. The 
cold front will sag southward across eastern MO through the Ohio 
Valley Tuesday as high pressure builds through the Great Lakes, 
while retreating northward across the plains region in response to 
the migratory surface low. No sensible weather with the front 
other than suppressing the temperatures a few degrees. 


Active weather remains centered on the Wednesday night-Thursday night 
period as the deep western upper trof progresses into the nations 
midsection. There are some questions initially Wednesday into 
Wednesday night on the rate of eastward spread of precipitation as 
the NAM and local WRF are quite a bit slower than the other operational 
models. At this time I am favoring the more agressive GFS/ECMWF. An 
intensifying and veering southwesterly low level jet and associated the pre- 
frontal warm advection regime, along with weak impulses moving 
across the region within the southwest flow aloft, would suggest 
more progressive nature to the convection/mesoscale convective system on Wednesday night. 
Thunderstorms will remain likely Thursday/Thursday night as the 
main short wave trof and attendant cold move across the region. Much 
cooler weather remains on track in the wake of the cold front Friday 
into Saturday with gusty northwest winds on Friday. Temperatures 
return to seasonable normals on Sunday. 


Glass 


&& 


Aviation: (for the 06z tafs through 06z Tuesday night) 
issued at 1151 PM CDT Mon Sep 29 2014 


Weak cold front to continue sliding south towards forecast area 
early this morning. Some low stratus has developed behind this 
boundary. Short range models want to bring stratus into KUIN 
towards daybreak, then slowly break it up. For now will just add 
scattered/broken mention to KUIN by 11z Tuesday, then scatter out by 
16z Tuesday. As for rest of taf sites, just light and variable winds 
becoming easterly as boundary slides through. 


Specifics for kstl: 
weak cold front to continue sliding south towards forecast area 
early this morning. Some low stratus has developed behind this 
boundary. Short range models want to bring stratus near Metro area 
then break it up. For now will leave out mention. Just have light 
and variable winds becoming easterly as boundary slides through by 
midday today. 


Byrd 
&& 


Lsx watches/warnings/advisories: 
MO...none. 
Illinois...none. 
&& 


$$ 
Weather forecast office lsx 



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