Dekalb, Illinois Weather Conditions

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Current Conditions

  • 81°
  • Clear
  • Wind: SW 7 mph
  • Humidity: 58%
  • Visibility: 10.0 miles
  • Dew Point: 65°
  • Pressure: 29.89 in. 0
  • Heat Index: 82

Select a Section

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Next 12 Hours

4  pm
7  pm
10  pm
1  am
4  am
Mostly Cloudy
Mostly Cloudy
Thunderstorm
T-storms
Thunderstorm
T-storms
Thunderstorm
T-storms
Thunderstorm
T-storms
82°
77°
70°
68°
66°
Forecast data from the National Digital Forecast Database.

5 Day Forecast

  • Wednesday
  • Thunderstorm
  • High: 84 °
  • Low: 66 °
  • Thunderstorm
  • Thursday
  • Thunderstorm
  • High: 88 °
  • Low: 70 °
  • T-Storms
  • Friday
  • Chance of a Thunderstorm
  • High: 88 °
  • Low: 68 °
  • Chance of T-Storms
  • Saturday
  • Chance of a Thunderstorm
  • High: 90 °
  • Low: 73 °
  • Chance of T-Storms
  • Sunday
  • Partly Cloudy
  • High: 88 °
  • Low: 70 °
  • Partly Cloudy

Forecast for Dekalb, Illinois

Updated: 4:00 PM CDT on August 20, 2014

  • Wednesday

    Partly cloudy. High of 84F. Winds from the West at 5 to 10 mph. Chance of rain 20%.

  • Wednesday Night

    Mostly cloudy with thunderstorms and rain showers. Low of 66F. Winds less than 5 mph. Chance of rain 70% with rainfall amounts near 0.3 in. possible.

  • Thursday

    Overcast with thunderstorms and rain showers, then a chance of a thunderstorm and a chance of rain in the afternoon. High of 88F with a heat index of 93F. Winds from the South at 5 to 10 mph. Chance of rain 60%.

  • Thursday Night

    Partly cloudy with a chance of a thunderstorm and a chance of rain. Low of 70F. Winds from the SSW at 5 to 10 mph. Chance of rain 20%.

  • Friday

    Partly cloudy with a chance of a thunderstorm and a chance of rain. High of 88F with a heat index of 95F. Winds from the WSW at 5 to 10 mph. Chance of rain 30%.

  • Friday Night

    Partly cloudy with a chance of a thunderstorm and rain. Fog overnight. Low of 68F. Winds from the WSW at 5 to 10 mph. Chance of rain 50%.

  • Saturday

    Overcast with a chance of a thunderstorm and rain. Fog early. High of 90F with a heat index of 108F. Winds less than 5 mph. Chance of rain 70% with rainfall amounts near 0.3 in. possible.

  • Saturday Night

    Overcast with a chance of a thunderstorm and rain in the evening, then mostly cloudy. Low of 73F. Winds from the ESE at 5 to 10 mph. Chance of rain 40%.

  • Sunday

    Partly cloudy. High of 88F with a heat index of 95F. Winds from the South at 5 to 10 mph.

  • Sunday Night

    Partly cloudy with a chance of a thunderstorm. Low of 70F. Winds from the SW at 5 to 10 mph. Chance of rain 40%.

  • Monday

    Partly cloudy. High of 84F. Winds less than 5 mph.

  • Monday Night

    Partly cloudy. Fog overnight. Low of 61F. Winds less than 5 mph.

  • Tuesday

    Mostly cloudy with a chance of a thunderstorm. Fog early. High of 81F. Winds less than 5 mph. Chance of rain 40%.

  • Tuesday Night

    Partly cloudy with a chance of a thunderstorm. Fog overnight. Low of 59F. Winds from the SSE at 5 to 10 mph. Chance of rain 60% with rainfall amounts near 0.3 in. possible.

  • Wednesday

    Partly cloudy with a chance of a thunderstorm. Fog early. High of 81F. Winds from the SSW at 5 to 10 mph. Chance of rain 60%.

  • Wednesday Night

    Mostly cloudy with a chance of a thunderstorm. Fog overnight. Low of 61F. Winds from the SW at 5 to 10 mph. Chance of rain 60% with rainfall amounts near 0.2 in. possible.

  • Thursday

    Mostly cloudy with a chance of a thunderstorm. Fog early. High of 72F. Winds less than 5 mph. Chance of rain 20%.

  • Thursday Night

    Partly cloudy. Low of 57F. Winds less than 5 mph.

  • Friday

    Clear. High of 70F. Winds less than 5 mph.

  • Friday Night

    Clear. Low of 55F. Winds less than 5 mph.

  • Saturday

    Clear. High of 72F. Winds less than 5 mph.

  • Saturday Night

    Clear. Low of 55F. Winds less than 5 mph.

  • Sunday

    Clear. High of 72F. Winds less than 5 mph.

  • Sunday Night

    Clear. Low of 55F. Winds less than 5 mph.

Severe Weather Alert Descriptions

 Public Information Statement  Statement as of 10:18 am CDT on August 20, 2014


... Morning rainfall Roundup...

   the following are rain amounts for the previous 24-hours
   as measured in the morning by NWS cooperative observers
   and cocorahs observers.
   Observations are usually taken between 6 and 8 am.

   24-hour rainfall amounts
       for wednesday(08/20/14)...


Illinois rain
location (county): fall (in)

Chicago 5ne (cook)... ... ... ... ... ... ... ... ... 1.59
Seneca 2ssw (la salle)... ... ... ... ... ... ... ..0.92
Morris 6ese (grundy)... ... ... ... ... ... ... ... .0.82
Oak Park 2s (cook)... ... ... ... ... ... ... ... ... 0.72
Braceville (grundy)... ... ... ... ... ... ... ... ..0.71
Coal City 4nnw (grundy)... ... ... ... ... ... ... .0.66
Carbon Hill 3.1n (grundy)... ... ... ... ... ... ..0.66
Morris 2sse (grundy)... ... ... ... ... ... ... ... .0.62
South Wilmington (grundy)... ... ... ... ... ... ..0.61
Mundelein 2wnw (lake)... ... ... ... ... ... ... ... 0.57
Oak Park 1sw (cook)... ... ... ... ... ... ... ... ..0.56
Wilmington 6nw (will)... ... ... ... ... ... ... ... 0.50
Chenoa 4nnw (livingston)... ... ... ... ... ... ... 0.49
Bradley 1sw (kankakee)... ... ... ... ... ... ... ..0.48
Kankakee (kankakee)... ... ... ... ... ... ... ... ..0.45
Marseilles (la salle)... ... ... ... ... ... ... ... 0.45
Streator (livingston)... ... ... ... ... ... ... ... 0.41
Dwight 4nnw (grundy)... ... ... ... ... ... ... ... .0.39
La Grange Park 1ssw (cook)... ... ... ... ... ... .0.34
Romeoville (will)... ... ... ... ... ... ... ... ... .0.34
Coal City (grundy)... ... ... ... ... ... ... ... ... 0.33
Bourbonnais 2nne (kankakee)... ... ... ... ... ... 0.32
Flossmoor (cook)... ... ... ... ... ... ... ... ... ..0.31
Dwight (livingston)... ... ... ... ... ... ... ... ..0.30
Bourbonnais 3e (kankakee)... ... ... ... ... ... ..0.28
Chebanse (kankakee)... ... ... ... ... ... ... ... ..0.26
Bourbonnais (kankakee)... ... ... ... ... ... ... ..0.24
Bonfield 4wsw (kankakee)... ... ... ... ... ... ... 0.24
Crete 3e (will)... ... ... ... ... ... ... ... ... ... 0.23
Plainfield 2sse (will)... ... ... ... ... ... ... ..0.23
Pontiac 1se (livingston)... ... ... ... ... ... ... 0.22
Morris (grundy)... ... ... ... ... ... ... ... ... ... 0.22
River Forest 1sse (cook)... ... ... ... ... ... ... 0.21
Glencoe (cook)... ... ... ... ... ... ... ... ... ... .0.21
Homewood (cook)... ... ... ... ... ... ... ... ... ... 0.21
Bonfield 4nne (kankakee)... ... ... ... ... ... ... 0.21
Plainfield 3se (will)... ... ... ... ... ... ... ... 0.21
Manhattan 2se (will)... ... ... ... ... ... ... ... .0.21
Joliet 2n (will)... ... ... ... ... ... ... ... ... ..0.21
Pontiac (livingston)... ... ... ... ... ... ... ... .0.21
Joliet 2nne (will)... ... ... ... ... ... ... ... ... 0.20
St Anne (kankakee)... ... ... ... ... ... ... ... ... 0.20
Botanic Gardens (cook)... ... ... ... ... ... ... ..0.19
Joliet 3wnw (will)... ... ... ... ... ... ... ... ... 0.19
Winnetka 1s (cook)... ... ... ... ... ... ... ... ... 0.18
Elgin 2w (kane)... ... ... ... ... ... ... ... ... ... 0.18
Joliet (will)... ... ... ... ... ... ... ... ... ... ..0.18
Homer Glen 1ene (will)... ... ... ... ... ... ... ..0.17
Milford (iroquois)... ... ... ... ... ... ... ... ... 0.17
New Lenox 1ne (will)... ... ... ... ... ... ... ... .0.16
Plainfield 5sw (kendall)... ... ... ... ... ... ... 0.15
Beach Park 1w (lake)... ... ... ... ... ... ... ... .0.15
New Lenox 4se (will)... ... ... ... ... ... ... ... .0.15
Chicago 6ese (cook)... ... ... ... ... ... ... ... ..0.14
Alsip (cook)... ... ... ... ... ... ... ... ... ... ... 0.14
Lockport 1se (will)... ... ... ... ... ... ... ... ..0.14
Lake Villa 1ssw (lake)... ... ... ... ... ... ... ..0.13
Wadsworth 1sse (lake)... ... ... ... ... ... ... ... 0.13
Manhattan 5ene (will)... ... ... ... ... ... ... ... 0.13
midway (cook)... ... ... ... ... ... ... ... ... ... ..0.13
Channahon (will)... ... ... ... ... ... ... ... ... ..0.12
Kankakee 3se (kankakee)... ... ... ... ... ... ... .0.12
New Lenox 2se (will)... ... ... ... ... ... ... ... .0.12
Plainfield 1sw (will)... ... ... ... ... ... ... ... 0.12
Orland Park 5wnw (will)... ... ... ... ... ... ... .0.12
Manhattan (will)... ... ... ... ... ... ... ... ... ..0.12
Wheeling (cook)... ... ... ... ... ... ... ... ... ... 0.12
Elgin (kane)... ... ... ... ... ... ... ... ... ... ... 0.11
Kankakee (kankakee)... ... ... ... ... ... ... ... ..0.11
Oak Lawn (cook)... ... ... ... ... ... ... ... ... ... 0.11
Palos Park 1sw (cook)... ... ... ... ... ... ... ... 0.11
Elgin 1s (kane)... ... ... ... ... ... ... ... ... ... 0.11
Waukegan (lake)... ... ... ... ... ... ... ... ... ... 0.11
Glenwood 2ese (cook)... ... ... ... ... ... ... ... .0.10
Chicago Ridge (cook)... ... ... ... ... ... ... ... .0.10
Marseilles 5wnw (la salle)... ... ... ... ... ... .0.10
Ottawa (la salle)... ... ... ... ... ... ... ... ... .0.10
Schaumburg 3wsw (cook)... ... ... ... ... ... ... ..0.09
Oak Lawn 2wnw (cook)... ... ... ... ... ... ... ... .0.09
Oak Park 1nne (cook)... ... ... ... ... ... ... ... .0.09
Westmont 1sse (du page)... ... ... ... ... ... ... .0.09
Homer Glen 4wnw (will)... ... ... ... ... ... ... ..0.09
Wilmington 3se (will)... ... ... ... ... ... ... ... 0.09
Fairbury (livingston)... ... ... ... ... ... ... ... 0.08
Downers Grove 2se (du page)... ... ... ... ... ... 0.08
Streator 1s (livingston)... ... ... ... ... ... ... 0.08
Lake Zurich (lake)... ... ... ... ... ... ... ... ... 0.08
Lansing (cook)... ... ... ... ... ... ... ... ... ... .0.08
Orland Hills 1se (cook)... ... ... ... ... ... ... .0.07
Park Forest 1sw (cook)... ... ... ... ... ... ... ..0.07
Bolingbrook 3ne (du page)... ... ... ... ... ... ..0.07
Minooka (grundy)... ... ... ... ... ... ... ... ... ..0.07
midway coop (cook)... ... ... ... ... ... ... ... ... 0.07
ohare (cook)... ... ... ... ... ... ... ... ... ... ... 0.07
Lansing (cook)... ... ... ... ... ... ... ... ... ... .0.06
Elk Grove Village 2wsw (cook)... ... ... ... ... .0.06
Burr Ridge 2sw (du page)... ... ... ... ... ... ... 0.06
Ashkum 5.6e (iroquois)... ... ... ... ... ... ... ..0.06
Lincolnshire 1.3wsw (lake)... ... ... ... ... ... .0.06
Spring Grove 2n (mchenry)... ... ... ... ... ... ..0.06
Westmont (du page)... ... ... ... ... ... ... ... ... 0.06
Marseilles 6wnw (la salle)... ... ... ... ... ... .0.05
Channahon 1nne (will)... ... ... ... ... ... ... ... 0.05
Oak Lawn 2se (cook)... ... ... ... ... ... ... ... ..0.04
Marseilles 3nw (la salle)... ... ... ... ... ... ..0.04
Plainfield (will)... ... ... ... ... ... ... ... ... .0.04
Elmhurst 1ese (du page)... ... ... ... ... ... ... .0.03
Elmhurst 2se (du page)... ... ... ... ... ... ... ..0.03
Buffalo Grove 2n (lake)... ... ... ... ... ... ... .0.03
Sheridan 3sse (la salle)... ... ... ... ... ... ... 0.03
New Lenox 2se (will)... ... ... ... ... ... ... ... .0.03
New Lenox 3e (will)... ... ... ... ... ... ... ... ..0.03
Hoffman Estates 5w (cook)... ... ... ... ... ... ..0.02
Park Ridge 1wnw (cook)... ... ... ... ... ... ... ..0.02
Glenview 1sw (cook)... ... ... ... ... ... ... ... ..0.02
Arlington Heights 2nnw (cook)... ... ... ... ... .0.02
Lincolnwood 2e (cook)... ... ... ... ... ... ... ... 0.02
Waukegan 2n (lake)... ... ... ... ... ... ... ... ... 0.02
Antioch 3wsw (lake)... ... ... ... ... ... ... ... ..0.02
Peotone (will)... ... ... ... ... ... ... ... ... ... .0.02
Naperville 4ssw (will)... ... ... ... ... ... ... ..0.02
Joliet lock/dam (will)... ... ... ... ... ... ... ..0.02
Peotone (will)... ... ... ... ... ... ... ... ... ... .0.02
Yorkville 2se (kendall)... ... ... ... ... ... ... .0.02
Elgin (kane)... ... ... ... ... ... ... ... ... ... ... 0.01
Schaumburg 2e (cook)... ... ... ... ... ... ... ... 0.01
Worth (cook)... ... ... ... ... ... ... ... ... ... ... 0.01
Bartlett 1se (du page)... ... ... ... ... ... ... ..0.01
Gibson 3wnw (ford)... ... ... ... ... ... ... ... ... 0.01
St. Charles 6nw (kane)... ... ... ... ... ... ... ..0.01
Gurnee 2ne (lake)... ... ... ... ... ... ... ... ... .0.01
Gurnee 2w (lake)... ... ... ... ... ... ... ... ... ..0.01
Ottawa 2n (la salle)... ... ... ... ... ... ... ... .0.01
Mendota 2se (la salle)... ... ... ... ... ... ... ..0.01
Algonquin 1n (mchenry)... ... ... ... ... ... ... ..0.01
Barrington (lake)... ... ... ... ... ... ... ... ... trace
West Chicago (du page)... ... ... ... ... ... ... .trace
Park Ridge (cook)... ... ... ... ... ... ... ... ... trace
Aurora 4se (du page)... ... ... ... ... ... ... ... trace
Lisle (du page)... ... ... ... ... ... ... ... ... ..Trace
Lisle 1se (du page)... ... ... ... ... ... ... ... .Trace
Naperville 1nw (du page)... ... ... ... ... ... ..trace
Lombard 1nnw (du page)... ... ... ... ... ... ... .trace
Watseka 6.9wnw (iroquois)... ... ... ... ... ... .trace
Yorkville 1w (kendall)... ... ... ... ... ... ... .trace
Winthrop Harbor (lake)... ... ... ... ... ... ... .trace
Ottawa 1nw (la salle)... ... ... ... ... ... ... ..trace
La Salle (la salle)... ... ... ... ... ... ... ... .Trace
Plainfield 3nnw (will)... ... ... ... ... ... ... .trace
Mundelein (lake)... ... ... ... ... ... ... ... ... .trace
Rockford (winnebago)... ... ... ... ... ... ... ... trace
Watseka (iroquois)... ... ... ... ... ... ... ... ..trace

Indiana rain
location (county): fall (in)

Remington (jasper)... ... ... ... ... ... ... ... ... 1.70
Remington (jasper)... ... ... ... ... ... ... ... ... 0.91
Kentland 1nnw (newton)... ... ... ... ... ... ... ..0.71
Kentland (newton)... ... ... ... ... ... ... ... ... .0.63
Earl Park 2sse (benton)... ... ... ... ... ... ... .0.50
de motte 4sw (jasper)... ... ... ... ... ... ... ... 0.41
Kentland 2sse (newton)... ... ... ... ... ... ... ..0.35
de motte 6s (jasper)... ... ... ... ... ... ... ... .0.30
Rensselaer 5e (jasper)... ... ... ... ... ... ... ..0.27
Wheatfield 3s (jasper)... ... ... ... ... ... ... ..0.26
Fair Oaks 6sw (newton)... ... ... ... ... ... ... ..0.21
Wheatfield 2ene (jasper)... ... ... ... ... ... ... 0.20
Lake Village 2w (newton)... ... ... ... ... ... ... 0.19
Kouts 2wsw (porter)... ... ... ... ... ... ... ... ..0.16
(w9opr)wheatfield 1ene (jasper)... ... ... ... ..0.15
Lake Village 8se (newton)... ... ... ... ... ... ..0.14
Rensselaer 10nne (jasper)... ... ... ... ... ... ..0.11
Wheatfield 5w (jasper)... ... ... ... ... ... ... ..0.11
de motte 1ssw (jasper)... ... ... ... ... ... ... ..0.10
Rensselaer (jasper)... ... ... ... ... ... ... ... ..0.10
de motte 1nnw (jasper)... ... ... ... ... ... ... ..0.09
St. John (lake)... ... ... ... ... ... ... ... ... ... 0.09
Morocco (newton)... ... ... ... ... ... ... ... ... ..0.08
Hobart 1nnw (lake)... ... ... ... ... ... ... ... ... 0.07
Rensselaer 5nw (jasper)... ... ... ... ... ... ... .0.06
Hobart 1ssw (lake)... ... ... ... ... ... ... ... ... 0.06
Chesterton 1ene (porter)... ... ... ... ... ... ... 0.05
Gary 5ene (lake)... ... ... ... ... ... ... ... ... ..0.03
brook 4w (newton)... ... ... ... ... ... ... ... ... .0.03
(kb9f)valparaiso 4s (porter)... ... ... ... ... ..0.03
(w9mal)merrillville 2nnw (lake)... ... ... ... ..0.02
Portage 1ese (porter)... ... ... ... ... ... ... ... 0.02
Porter 1s (porter)... ... ... ... ... ... ... ... ... 0.02
Crown Point (lake)... ... ... ... ... ... ... ... ... 0.01
Valparaiso 1se (porter)... ... ... ... ... ... ... Trace
Valparaiso 4sw (porter)... ... ... ... ... ... ... Trace
Valparaiso (porter)... ... ... ... ... ... ... ... .Trace



Personal Weather Stations

Personal Weather Stations [Add your weather station!]

Location: South DeKalb, DeKalb, IL

Updated: 3:24 PM CDT

Temperature: 82.9 °F Dew Point: 70 °F Humidity: 66% Wind: Calm Pressure: 29.82 in Hourly Precipitation: 0.00 in Heat Index: 87 °F Graphs

Location: Northern Illinois University, DeKalb, IL

Updated: 3:24 PM CDT

Temperature: 83.5 °F Dew Point: 68 °F Humidity: 60% Wind: Calm Pressure: 29.76 in Hourly Precipitation: 0.00 in Heat Index: 87 °F Graphs

Location: Rob's Horsepower Haven, DeKalb, IL

Updated: 3:24 PM CDT

Temperature: 87.0 °F Dew Point: 69 °F Humidity: 56% Wind: Calm Pressure: 29.82 in Hourly Precipitation: 0.00 in Heat Index: 92 °F Graphs

Location: DeKalb, IL

Updated: 3:18 PM CDT

Temperature: 82.0 °F Dew Point: 69 °F Humidity: 64% Wind: SSW at 8.0 mph Pressure: 29.81 in Hourly Precipitation: - Heat Index: 85 °F Graphs

Location: Sycamore, IL

Updated: 3:24 PM CDT

Temperature: 85.0 °F Dew Point: 67 °F Humidity: 55% Wind: SSW at 3.0 mph Pressure: 29.85 in Hourly Precipitation: 0.00 in Heat Index: 88 °F Graphs

Location: MesoWest MALTA1 IL US UPR, Malta, IL

Updated: 2:25 PM CDT

Temperature: 83 °F Dew Point: - Humidity: - Wind: Calm Pressure: - Hourly Precipitation: 0.00 in Heat Index: 81 °F Graphs

Location: MesoWest IL-64 @ Virgil Drainage Ditch IL US ILDOT, Sycamore, IL

Updated: 12:26 PM CDT

Temperature: 85 °F Dew Point: 74 °F Humidity: 71% Wind: SW at 6 mph Pressure: - Hourly Precipitation: 0.00 in Heat Index: 93 °F Graphs

Location: Heron Creek, Sycamore, IL

Updated: 3:24 PM CDT

Temperature: 83.4 °F Dew Point: 66 °F Humidity: 56% Wind: Calm Pressure: 29.88 in Hourly Precipitation: 0.00 in Heat Index: 86 °F Graphs

Location: OG Heron Creek, Sycamore, IL

Updated: 3:24 PM CDT

Temperature: 83.3 °F Dew Point: 68 °F Humidity: 59% Wind: WNW at 8.1 mph Pressure: 29.83 in Hourly Precipitation: 0.00 in Heat Index: 86 °F Graphs

Location: The Rockin' N, Waterman, IL

Updated: 3:24 PM CDT

Temperature: 85.1 °F Dew Point: - Humidity: - Wind: North at - Pressure: 29.81 in Hourly Precipitation: - Heat Index: - Graphs

Location: Out On the Farm, Clare, IL

Updated: 3:21 PM CDT

Temperature: 84.1 °F Dew Point: 71 °F Humidity: 64% Wind: SW at 1.0 mph Pressure: 29.83 in Hourly Precipitation: 0.00 in Heat Index: 89 °F Graphs

Location: Ellen Oaks Subdivision, Genoa, IL

Updated: 3:24 PM CDT

Temperature: 82.2 °F Dew Point: 69 °F Humidity: 64% Wind: SSW at 3.0 mph Pressure: 29.83 in Hourly Precipitation: 0.00 in Heat Index: 86 °F Graphs

Location: Country Meadows, Kirkland, IL

Updated: 3:23 PM CDT

Temperature: 84.0 °F Dew Point: 68 °F Humidity: 58% Wind: SW at 8.0 mph Pressure: 29.79 in Hourly Precipitation: 0.00 in Heat Index: 87 °F Graphs

Location: MesoWest ELBRN1 IL US UPR, Elburn, IL

Updated: 1:40 PM CDT

Temperature: 87 °F Dew Point: - Humidity: - Wind: Calm Pressure: - Hourly Precipitation: 0.00 in Heat Index: 84 °F Graphs

Location: Genoa Road, Genoa, IL

Updated: 3:11 PM CDT

Temperature: 82.3 °F Dew Point: 71 °F Humidity: 69% Wind: Calm Pressure: 29.84 in Hourly Precipitation: 0.00 in Heat Index: 87 °F Graphs

Location: Columbine Square, Elburn, IL

Updated: 3:24 PM CDT

Temperature: 85.1 °F Dew Point: 71 °F Humidity: 63% Wind: SSE at 1.0 mph Pressure: 29.79 in Hourly Precipitation: 0.00 in Heat Index: 90 °F Graphs

Location: Prairie Highlands, Elburn, IL

Updated: 3:20 PM CDT

Temperature: 83.3 °F Dew Point: 70 °F Humidity: 64% Wind: West at 1.0 mph Pressure: 29.84 in Hourly Precipitation: 0.00 in Heat Index: 87 °F Graphs

Location: Cheval-De-Selle, Elburn, IL

Updated: 3:14 PM CDT

Temperature: 80.6 °F Dew Point: 69 °F Humidity: 67% Wind: NNW at 2.7 mph Pressure: 29.78 in Hourly Precipitation: - Heat Index: 84 °F Graphs

Location: MesoWest I-39 @ MP 81 / Lee County IL US ILDOT, Steward, IL

Updated: 12:25 PM CDT

Temperature: 80 °F Dew Point: 66 °F Humidity: 63% Wind: NE at 5 mph Pressure: - Hourly Precipitation: 0.00 in Heat Index: 82 °F Graphs

Location: Hampshire, IL, Hampshire, IL

Updated: 3:24 PM CDT

Temperature: 84.1 °F Dew Point: 68 °F Humidity: 59% Wind: West at 9.0 mph Pressure: 29.86 in Hourly Precipitation: 0.00 in Heat Index: 87 °F Graphs

Location: K9GPC, Rochelle, IL

Updated: 3:24 PM CDT

Temperature: 88.7 °F Dew Point: -10 °F Humidity: 2% Wind: Calm Pressure: 29.12 in Hourly Precipitation: 0.00 in Heat Index: 85 °F Graphs

Location: CamptonHillsWeather.com Central Kane County, St Charles, IL

Updated: 3:24 PM CDT

Temperature: 84.7 °F Dew Point: 70 °F Humidity: 62% Wind: WNW at 1.0 mph Pressure: 29.85 in Hourly Precipitation: 0.00 in Heat Index: 89 °F Graphs

Location: Campton Hills, Campton Hills, IL

Updated: 3:24 PM CDT

Temperature: 87.8 °F Dew Point: 67 °F Humidity: 51% Wind: Calm Pressure: 29.85 in Hourly Precipitation: 0.00 in Heat Index: 91 °F Graphs

Location: Windswept Acres, Marengo, IL

Updated: 3:19 PM CDT

Temperature: 83.8 °F Dew Point: 69 °F Humidity: 62% Wind: SW at 5.0 mph Pressure: 29.81 in Hourly Precipitation: 0.00 in Heat Index: 88 °F Graphs

Location: Hidden Farms Estates, Marengo, IL

Updated: 3:21 PM CDT

Temperature: 83.9 °F Dew Point: 69 °F Humidity: 61% Wind: WNW at 2.0 mph Pressure: 29.84 in Hourly Precipitation: 0.00 in Heat Index: 88 °F Graphs

Location: Mill Creek, Geneva, IL

Updated: 3:22 PM CDT

Temperature: 82.4 °F Dew Point: 69 °F Humidity: 63% Wind: WNW at 1.0 mph Pressure: 29.79 in Hourly Precipitation: 0.00 in Heat Index: 86 °F Graphs

Location: Mill Creek (NE), Geneva, IL

Updated: 3:24 PM CDT

Temperature: 82.8 °F Dew Point: 69 °F Humidity: 64% Wind: Calm Pressure: 29.82 in Hourly Precipitation: 0.00 in Heat Index: 87 °F Graphs

Location: MesoWest FLAGG1 IL US UPR, Ashton, IL

Updated: 1:15 PM CDT

Temperature: 81 °F Dew Point: - Humidity: - Wind: Calm Pressure: - Hourly Precipitation: 0.00 in Heat Index: 79 °F Graphs

Location: WB9NJJ, Rochelle, IL

Updated: 3:24 PM CDT

Temperature: 86.2 °F Dew Point: 45 °F Humidity: 24% Wind: Calm Pressure: 29.58 in Hourly Precipitation: 0.00 in Heat Index: 83 °F Graphs

Location: Plano, Plano, IL

Updated: 3:11 PM CDT

Temperature: 85.8 °F Dew Point: 70 °F Humidity: 59% Wind: Calm Pressure: 29.82 in Hourly Precipitation: 0.00 in Heat Index: 90 °F Graphs

Location: Creek Side, Elgin, IL

Updated: 3:24 PM CDT

Temperature: 90.2 °F Dew Point: 68 °F Humidity: 49% Wind: WNW at 1.8 mph Pressure: 28.98 in Hourly Precipitation: 0.00 in Heat Index: 95 °F Graphs

Location: Waterford Oaks, North Aurora, IL

Updated: 3:24 PM CDT

Temperature: 83.5 °F Dew Point: 71 °F Humidity: 65% Wind: West at 5.0 mph Pressure: 29.83 in Hourly Precipitation: 0.00 in Heat Index: 88 °F Graphs

Location: West Batavia, Batavia, IL

Updated: 3:20 PM CDT

Temperature: 83.1 °F Dew Point: 71 °F Humidity: 66% Wind: WNW at 3.0 mph Pressure: 29.81 in Hourly Precipitation: 0.00 in Heat Index: 88 °F Graphs

Location: Dover Ridge, Geneva, IL

Updated: 3:24 PM CDT

Temperature: 83.3 °F Dew Point: 68 °F Humidity: 60% Wind: WNW at 9.2 mph Pressure: 29.82 in Hourly Precipitation: 0.00 in Heat Index: 86 °F Graphs

Location: Rural--2.75 mi WSW Sandwich, IL, Sandwich, IL

Updated: 3:19 PM CDT

Temperature: 82.9 °F Dew Point: 66 °F Humidity: 56% Wind: Calm Pressure: 29.87 in Hourly Precipitation: 0.00 in Heat Index: 85 °F Graphs

Location: Gilberts, IL, Gilberts, IL

Updated: 3:24 PM CDT

Temperature: 84.6 °F Dew Point: 66 °F Humidity: 54% Wind: NNW at 6.0 mph Pressure: 30.08 in Hourly Precipitation: 0.00 in Heat Index: 87 °F Graphs

Location: Belvidere, Belvidere, IL

Updated: 3:23 PM CDT

Temperature: 91.9 °F Dew Point: 69 °F Humidity: 47% Wind: WSW at 2.7 mph Pressure: 29.59 in Hourly Precipitation: - Heat Index: 97 °F Graphs

MSN Maps of:

Temp: Dew Point: Humidity Wind Pressure Hr Precip -

NWS Forecaster Discussion




Area forecast discussion 
National Weather Service Chicago/Romeoville Illinois 
258 PM CDT Wednesday Aug 20 2014 


Discussion... 
320 am CDT 


Short term...through Wednesday night... 


For the remainder of the overnight hours...conditions will remain 
quiet with high pressure overhead and the pesky upper low lifting 
into the upper Great Lakes and any associated convection moving well 
to the east. Under clear skies and light winds...expect that some 
locations could see some fog development...mainly low lying and 
sheltered areas. Do not expect widespread dense fog as dewpoint 
depressions are still 3-5 degrees in many places. Conditions will 
remain quiet into Wednesday but upper ridging building over the 
Central Plains and across the middle and upper Mississippi Valley 
while the upper low continues to lift to the northeast is signaling 
the beginning of a significant warming trend...more like the true 
dog days of Summer that the unseasonably cool weather that the area 
has see for much of this Summer. Accompanying the upper ridging and 
increasing temperatures aloft will be an increase of low level 
moisture. The Bermuda high is in place over the eastern Gulf of Mexico while 
a trough of low pressure is developing over the Central Plains. 
This is setting up a return flow of moisture from a wide open Gulf 
of Mexico...with 20-30kt 850mb winds with trajectories off of the 
western Gulf of Mexico pointing right into the Midwest. Under ample sunshine 
for most of the day today...there should be little trouble mixing 
down the warmer air aloft...where 850mb temperatures should be around 
18-20c. So...the area will see highs today in the middle to upper 
80s. With dewpoints in the middle to upper 60s...the maximum heat index 
today should be in the upper 80s to lower 90s. While these heat 
index values are not anywhere near headline levels...they are 
certainly much higher than has been seen for the bulk of the 
Summer. 


Showers and thunderstorms will become an increasing concern through 
the afternoon and into Wednesday night. Early this morning...there 
is ongoing convection over the upper Missouri Valley associated with 
a shortwave over topping the upper ridge. Expect that this activity 
should slide southeast of the County Warning Area this morning...moving through southern 
Iowa/northern MO and into central/southern Illinois. The models are consistent in 
developing a warm front extending east from a deepening low over the 
Dakotas through the middle Mississippi Valley by early Wednesday 
evening. This should be the focus for rain showers/thunderstorms and rain spreading into the 
region from southwest to northeast through the evening and overnight 
hours Wednesday night. Have maintained a more broadbrushed 
appearance to the weather/pop/qpf grids for Wednesday night due to some 
concern with timing of the precipitation spreading northward as there is still some 
uncertainty in the models as far as timing the leading edge of the 
precipitation...but have gone with likely probability of precipitation as confidence is higher in the 
potential for precipitation. Confidence is just a little lower in the onset 
time. While the severe potential will be low...a greater concern 
will be locally heavy rainfall. As southwesterly flow and warm/moist 
advection increases through Wednesday night...the model guidance is 
indicating precipitable waters  around 2 inches over the area. With upper level 
winds from just above the surface through the column expected to be 
around 25-30kt...the thunderstorm activity should be progressive. 
So...while locally heavy rainfall is quite possible...widespread 
flooding is not anticipated though localized Urban and Small Stream 
advisory type flooding remains a possibility. 


Krein 


Thursday through Sunday... 
main concern in the medium term will reside on the 
placement/strength of the 500mb ridge poised to setup across the 
Ozarks. Guidance has been consistently suggesting an atmospheric 
river developing across the northern plains and becoming oriented 
along the northern periphery of the middle-level ridge...then turning 
southeast across the alleghenies in Pennsylvania. Concern does arise 
with the fact that medium range guidance has demonstrated a reduced 
level of confidence with spread in how amplified the ridge will 
become...which could be starting to hint that the active ring-o-fire 
may end up closer to the forecast area Thursday ngt/Fri. At this time 
have only made minor adjustments with the probability of precipitation...and expect a 
channel of likely probability of precipitation to be lifting north Thursday midday into wisc by 
Thursday night. Current oper solutions still favor this scenario...plus 
850mb temperatures will be steadily warming and should limit the coverage of 
convection/precip. 


Then into Friday solutions suggest the top of the ridge may begin to 
flatten. Local arw8km also hints that the active zone may be 
drifting south and could be over the forecast area Friday aftn/eve. 
Then for Sat ridge remains overhead...but it still looks possible 
for chance probability of precipitation to start the weekend. The one consistency through the 
Thursday-Sat timeframe...the heat/humidity. While precipitable water values continue 
to hover in the 1.6-1.8" range...the forecast dew points are expected 
to linger in the low to perhaps middle 70s for many locations thur-Sat. 
Surface temperatures are prognosticated to push well into the 80s...and perhaps warmer 
yet depending on cloud cover/precip. The combination of anomalously 
high dew points and surface temperatures in the upper 80s/near 90 would signal heat 
index values in the middle/upper 90s to perhaps the low 100s south of 
I-80...mainly Fri-sun. 


Early next week... 
ensembles and oper solutions continue to point towards the hot/humid 
airmass breaking down and transitioning back to a middle Continental U.S./Great 
Lakes trough. Monday will likely still be a hot/humid day. Guidance has 
demonstrated some confidence/consistency in a frontal boundary 
approaching the region Monday ngt/Tue...with much cooler air beginning 
to drive south across the northern plains Tuesday...and arriving across 
the County warning forecast area towards the middle of next week. 


Beachler 


&& 


Aviation... 


//Ord and mdw concerns...updated 20z... 


* lake breeze turning winds east/northeast this evening. 
* Low chance for thunderstorms and rain this afternoon/evening...then better chance 
for thunderstorms and rain overnight. 


Bmd 


//discussion...updated 18z... 


A frontal boundary straddles central Illinois this afternoon with 
convection ongoing near the front. SW to west-southwest winds are in place 
across the terminals this afternoon with a few sporadic gusts to 
around 20 knots. Winds will slowly veer to the west-northwest through the 
afternoon and a Late Lake breeze is expected to push across the 
terminals this evening turning winds to the northeast/east. A 
cumulus field has developed across far northern and northeast 
Illinois...north of the cirrus shield to our south and is showing 
some signs of vertical growth. Several higher res models do hint at 
isolated to widely scattered thunderstorms this afternoon where the 
cumulus field is currently in place. Coverage should remain low enough to 
preclude any mention in the taf at this time. Better chances for 
thunderstorms will develop tonight as the front starts to lift 
north. A low level jet will develop to our west with resulting 
convection tracking east towards the terminals late tonight. 
Thunderstorm probabilities will continue Thursday morning into early 
afternoon with the frontal boundary over northern Illinois and 
models suggesting that the area will remain unstable. Coverage is a 
concern so will maintain a prob30 for now. 


Bmd 


//Ord and mdw confidence...updated 20z... 


* high confidence in winds through early this evening...then low 
confidence in wind direction this evening and overnight. 
* Low confidence in thunderstorms and rain this afternoon/evening...then medium-high 
confidence in thunderstorms and rain late tonight into Thursday morning. 


Bmd 


//outlook for Ord/mdw for 00z Friday-12z Wednesday...updated 12z... 


* Thursday night through Tuesday...periodic chances for thunderstorms and rain. 


Krein 


&& 


Marine... 
158 PM CDT 


Fairly light wind regime is expected through the weekend with weak 
pressure gradient expected with high pressure over the St Lawrence 
valleys region and a trough of low pressure over the northern and 
Central Plains. A quasi-stationary warm front will extend east from 
the low into the lower Great Lakes region...with the position of the 
warm front likely being modulated at times by convective complexes. 


Izzi 


&& 


Lot watches/warnings/advisories... 
Illinois...none. 
In...none. 
Lm...none. 
&& 


$$ 


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