Thursday: Cloudy, then gradually becoming mostly sunny, with a high near 69. Northeast wind around 15 mph, with gusts as high as 20 mph.
Thursday Night: Mostly clear, with a low around 55. East wind 10 to 15 mph.
Friday: Sunny, with a high near 71. East wind 10 to 15 mph, with gusts as high as 20 mph.
Friday Night: Mostly clear, with a low around 53. East wind 5 to 10 mph.
Saturday: Sunny, with a high near 76.
Saturday Night: Mostly clear, with a low around 59.
Sunday: Sunny, with a high near 82.
Sunday Night: Mostly clear, with a low around 64.
Labor Day: Sunny, with a high near 82.
Monday Night: A chance of showers and thunderstorms. Mostly cloudy, with a low around 59.
Tuesday: Partly sunny, with a high near 71.
Tuesday Night: Partly cloudy, with a low around 52.
Wednesday: A slight chance of showers. Mostly sunny, with a high near 68.
Area Forecast Discussion below ad ...
AREA FORECAST DISCUSSION
National Weather Service Chicago/Romeoville, IL
GO Current Forecast Discussion
ARCHIVED
302 PM CDT Wed Aug 30 2017
.SHORT TERM... 302 PM CDT
Through Thursday...
For the remainder of the afternoon and through the evening, conditions across the area will remain quiet, with the only significant concern being how far inland a lake breeze boundary will penetrate. Latest radar ans satellite imagery indicate that a lake breeze has formed and is pushing inland from Lake Michigan. Temperatures should begin to drop off following the passage of the boundary, likely dropping into the 60s late this afternoon while temperatures across the remainder of the area climb into the upper 70s to around 80 F. There is a small chance for an isolated shower with the enhanced tcu along the boundary, but conditions should otherwise remain dry under partly sunny skies. Into the evening, the lake breeze should wash out and winds will settle back to light and variable as the region remains under a week gradient into the evening. Much of the cloud cover is diurnally driven, so skies should become mostly clear, at least for a while.
A cold front is pushing through northern Wisconsin and south down Lake Michigan. The models have been, and continue to trend a little slow with the progression of the front, as is fairly common with cold fronts pushing down the lake. Expect that there will continue to be an area of showers and thunderstorms along the front through the evening, but as the boundary reaches northern Illinois, which is expected to be arnd 1-2AM CDT, any thunder along the boundary should weaken and the coverage of showers should diminish as the front will be moving through the area at a diurnally unfavorable time for frontally induced weak convection. There will be a chance for some scattered showers through the early morning hours, but coverage will likely be sparse. As the front pushes into central IL/IN durg the late morning and into the afternoon hours, there should be an uptick in convective activity, but expect that the front will be south of the CWA before any convective activity begins.
Following the passage of the cold front, cool, moist flow off of Lake Michigan will bring overcast skies for the morning and early afternoon hours before high pressure spreading across the upper Great Lakes region helps to clear skies out in the afternoon. Under the cool nely flow, temperatures tomorrow should be well below normal, with highs along the lake front only in the middle to upper 60s and middle 70s inland.
&&
.LONG TERM... 210 PM CDT
Thursday night through Wednesday...
The long term forecast will see a number of frontal systems cross the area leading to periodic rain chances later in the holiday weekend and early next week before a cooler and drier pattern sets up for mid week. The Thursday cool front will be south of the area by evening with high pressure settling over the Great Lakes. Meanwhile, the remnants of Harvey will be working up the Ohio Valley, and , at this point, may only result in some increased higher level cloud cover over the extreme southeastern part of the forecast area Friday. The high will combine with the Harvey remnants to supply a steady easterly breeze Friday which will kee Pthe beach hazards going through about midday or so when winds begin to settle down. Highs will only be in the lower 70s with lakeshore areas having a tough time reaching 70. A southerly flow will set up allowing for warmer highs in the mid and upper 70s Saturday. Further warming will occur for Sunday with highs around 80. An upper trough will move east-southeast across the Canadian Prairies into the upper Mississippi River Valley Saturday as the surface high splits and is pushed out of the area. A weak cool front will cross the area Sunday but loses much of its focus as it arrives. The frontal passage looks largely dry Sunday but will have to keep an eye on low potential for some spotty shower activity. Will not see much cooling behind the front so Monday will see highs similar to Sunday. Another upper trough will be moving across central Canada with an associated surface low dragging a cold front across the area. Timing on this differs among the medium range models so will need to better identify where in the Monday afternoon to Monday night time frame it will pass and bring a chance for some rain. Once clear of the area, another upper trough will dig and amplify into the region bringing much cooler air aloft with 850 millibar temps falling to around 4 or 5 Celsius resulting in highs in the upper 60s to around 70 Wednesday. It also looks like lake effect showers will develop.
MDB
&&
.AVIATION... For the 18Z TAFs...
Several forecast concerns for the period, including lake breeze timing this afternoon...a cold front passage and associated wind shift, pcpn chances and mvfr cigs late tonight into tomorrow morning and then wind trends following the frontal passage.
With a weak pressure still in place, a lake breeze is expected to develop this afternoon. Latest high res model guidance suggests that the wind shift to ely should occur at ORD/MDW by btwn 19-20z with wind speed of 7-9 kt following the wind shift. The wind field should then settle into lgt/vrbl again by arnd sunset.
The remainder of forecast concerns will be associated with a cold front moving south through Wisconsin and Lake Michigan late tonight. Have only made some minor adjustments to the going forecast. Have continued the trend of speeding up the frontal passage and associated impacts given the tendency for these types of systems to progress faster than the model guidance would suggest. So, even though the model guidance is trending a little faster than previous runs, still feel that the front`s progression should still trend a little faster. Confidence is moderate with the timing of the fropa and the chances for mvfr cigs behind the front given the fetch of cool, moist air off of Lake Michigan in nely flow. The biggest question is pcpn coverage. Have relatively high confidence that there will be at least bkn shra coverage as the front moves south through Wisconsin, but the timing of the fropa through nrn IL/IN is diurnally unfavorable for widespread pcpn and the guidance does reflect the trend of pcpn coverage diminishing as the front pushes through the terminal areas late tonight. Pcpn coverage should then increase again durg the late morning and afternoon hours as it moves into cntrl IL/IN, but by that point, any pcpn should be well south of the terminals.
Winds will shift northeasterly behind the front and speeds will gradually increase to 10-15kts, with ocnl higher gusts likely.
&&
.MARINE... 234 PM CDT
A cold front will continue to drop down the lake this evening bringing a shift to north to northeast winds behind it. High pressure will build in behind the front Thursday morning keeping a stiff northeast wind across much of the lake into Friday morning. Will continue the small craft advisory for the Illinois nearshore waters and add the Indiana nearshore waters as well. Will start the small craft advisory tonight and continue it into Friday afternoon. The center of the high moves across northern lower Michigan later Friday allowing winds to diminish then turn southerly Saturday. A weakening cool front turns winds southwest Saturday night and then northwest Sunday morning as weak high pressure then slides to the southwest of the lake. A stronger low pressure system passes north of the lake Monday bringing stronger southerly winds before a cold front turns them northerly Monday or Monday night. Timing of this may change somewhat as it gets closer. Northerly winds persist through mid week.
MDB
&&
.LOT WATCHES/WARNINGS/ADVISORIES... IL...Beach Hazards Statement...ILZ006-ILZ014...4 AM Thursday to 4 PM Friday.
IN...Beach Hazards Statement...INZ001-INZ002...4 AM Thursday to 4 PM Friday.
LM...Small Craft Advisory...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744- LMZ745...4 AM Thursday to 4 PM Friday.
MORE BELOW
+ + + + + +
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NWS Forecast Chicago (O'Hare)
nexrad.chgowx.com
(NEXRAD Radar Chicago)
Arlingtoncardinal.com/radar
(Chicagoland Weather Radar)
Arlingtoncardinal.com/clouds
(Satellite Cloud Cover East United States)
Arlingtoncardinal.com/usforecastchart
(US Weather Forecast Chart)
Arlingtoncardinal.com/uvindex
Ultraviolet Index/UV Index
Arlingtoncardinal.com/sun
Chicagoland Sunrise, Sunset and Solar Information for Chicago area
Arlingtoncardinal.com/moon
Chicagoland Moonrise, Moonset and Lunar Phase information for Chicago area
Full climate/weather details chicagoweatherstation.com
(Desktop Mac/PC links)
Chicago record high temperatures
Chicago record low temperatures
Chicago extreme records
Chicago normal temperatures
Chicago Weather Radar
Chicago Weather Forecast
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Arlington Heights Weather Forecast
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allergy.chgowx.com
Chicago allergy weather
arthritis.chgowx.com
Chicago arthritis weather
respiratory.chgowx.com
Chicago respiratory weather
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Hazardous Weather Outlook National Weather Service Chicago/Romeoville IL 353 PM CDT Wed Aug 30 2017
ILZ003>006-008-010>014-019>023-032-033-039-INZ001-002-010-011-019- 312100- Winnebago-Boone-McHenry-Lake Illinois-Ogle-Lee-De Kalb-Kane- DuPage-Cook-La Salle-Kendall-Grundy-Will-Kankakee-Livingston- Iroquois-Ford-Lake Indiana-Porter-Newton-Jasper-Benton- 353 PM CDT Wed Aug 30 2017 /453 PM EDT Wed Aug 30 2017/
THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH CENTRAL ILLINOIS... NORTHEAST ILLINOIS AND NORTHWEST INDIANA.
.DAY ONE...Tonight.
WEATHER HAZARDS EXPECTED:
Limited Fog Risk late tonight. High Swim Risk late tonight.
DISCUSSION:
A cold front will settle across the area tonight, with winds becoming breezy from the northeast late. The northeast fetch will build waves along the Illinois and Indiana shores after midnight, making for dangerous swim conditions by morning. Patchy fog is possible overnight.
.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.
Thursday... Limited Fog Risk early. High Swim Risk. Friday... High Swim Risk. Monday... Limited Thunderstorm Risk.
.SPOTTER INFORMATION STATEMENT...
Spotter activation will not be necessary through tonight.
&&
$$
Beach Hazards Statement LAKESHORE HAZARD MESSAGE...CORRECTED NATIONAL WEATHER SERVICE CHICAGO IL 356 PM CDT WED AUG 30 2017
ILZ006-014-310415- /O.CON.KLOT.BH.S.0016.170831T0900Z-170901T2100Z/ LAKE IL-COOK- 356 PM CDT WED AUG 30 2017
...BEACH HAZARDS STATEMENT REMAINS IN EFFECT FROM LATE TONIGHT THROUGH FRIDAY AFTERNOON...
* LOCATION...ILLINOIS LAKE MICHIGAN BEACHES.
* FORECAST WAVE HEIGHTS...4 TO 6 FEET.
* STRONG RIP CURRENTS AND STRUCTURAL CURRENTS EXPECTED.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
LIFE THREATENING WAVES AND CURRENTS ARE EXPECTED AT THE BEACHES. PEOPLE VISITING THE BEACHES SHOULD STAY OUT OF THE WATER.
RIP CURRENTS ARE POWERFUL CHANNELS OF WATER FLOWING QUICKLY AWAY FROM SHORE, WHICH OCCUR MOST OFTEN AT LOW SPOTS OR BREAKS IN SANDBARS. RIP CURRENTS CAN SWEEP YOU INTO DEEPER WATER.
STRUCTURAL CURRENTS FORM ALONG PIERS WHERE LONGSHORE CURRENTS AND WAVE ACTION FLOW INTO THE STRUCTURE. STRUCTURAL CURRENTS CAN SWEEP YOU INTO DEEPER WATER ALONG THE PIER STRUCTURE.
EXPOSED BEACHES ARE MORE LIKELY TO EXPERIENCE THE MOST SIGNIFICANT WAVE AND CURRENT IMPACTS. IMPACTS AT BEACHES WITH PROTECTIVE BREAKWALLS OR JETTIES WILL BE SUBJECT TO THE ORIENTATION OF STRUCTURES AS WELL AS WIND AND WAVE DIRECTION.
FOR INFORMATION ON SWIM ADVISORIES OR BANS AT CHICAGO BEACHES VISIT: WWW.CPDBEACHES.COM.
LAKESHORE HAZARD MESSAGE...CORRECTED
NATIONAL WEATHER SERVICE CHICAGO IL
356 PM CDT WED AUG 30 2017
ILZ006-014-310415-
/O.CON.KLOT.BH.S.0016.170831T0900Z-170901T2100Z/
LAKE IL-COOK-
356 PM CDT WED AUG 30 2017
...BEACH HAZARDS STATEMENT REMAINS IN EFFECT FROM LATE TONIGHT
THROUGH FRIDAY AFTERNOON...
* LOCATION...ILLINOIS LAKE MICHIGAN BEACHES.
* FORECAST WAVE HEIGHTS...4 TO 6 FEET.
* STRONG RIP CURRENTS AND STRUCTURAL CURRENTS EXPECTED.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
LIFE THREATENING WAVES AND CURRENTS ARE EXPECTED AT THE BEACHES.
PEOPLE VISITING THE BEACHES SHOULD STAY OUT OF THE WATER.
RIP CURRENTS ARE POWERFUL CHANNELS OF WATER FLOWING QUICKLY AWAY
FROM SHORE, WHICH OCCUR MOST OFTEN AT LOW SPOTS OR BREAKS IN
SANDBARS. RIP CURRENTS CAN SWEEP YOU INTO DEEPER WATER.
STRUCTURAL CURRENTS FORM ALONG PIERS WHERE LONGSHORE CURRENTS AND
WAVE ACTION FLOW INTO THE STRUCTURE. STRUCTURAL CURRENTS CAN
SWEEP YOU INTO DEEPER WATER ALONG THE PIER STRUCTURE.
EXPOSED BEACHES ARE MORE LIKELY TO EXPERIENCE THE MOST
SIGNIFICANT WAVE AND CURRENT IMPACTS. IMPACTS AT BEACHES WITH
PROTECTIVE BREAKWALLS OR JETTIES WILL BE SUBJECT TO THE
ORIENTATION OF STRUCTURES AS WELL AS WIND AND WAVE DIRECTION.
FOR INFORMATION ON SWIM ADVISORIES OR BANS AT CHICAGO BEACHES
VISIT: WWW.CPDBEACHES.COM.