|
Marine Weather and Tides
Version 3.4 |
3/3/2018 - There is a new GOES Satellite for the east coast that required rewriting that part of the code. Please report any issues. 6/25/2017 - NOAA is having a major issue that impact the 7 day forecast load times. Many users are reporting problems. The issue has been reported. 5/23/2017 - Worked with NOAA again to speed up the 7 day forecast load times. Thanks to them for being responsive. |
Sunrise 5:52AM | Sunset 7:44PM | Wednesday April 25, 2018 1:12 PM CDT (18:12 UTC) | Moonrise 3:07PM | Moonset 3:55AM | Illumination 79% | ![]() |
Marine Forecasts
EDIT (on/off)  HelpLMZ742 Winthrop Harbor To Wilmette Harbor- Wilmette Harbor To Northerly Island- Northerly Island To Calumet Harbor- 947 Am Cdt Wed Apr 25 2018 .small craft advisory in effect through this evening... Today..North winds to 30 kt diminishing 20 to 25 kt by early afternoon then to 15 to 20 kt late in the afternoon. Sunny. Waves 6 to 9 ft occasionally to 12 ft subsiding to 4 to 6 ft occasionally to 8 ft. Tonight..North winds 10 to 15 kt. Clear. Waves 3 to 6 ft occasionally to 8 ft subsiding to 2 to 4 ft by midnight. Thursday..Southwest winds 5 to 10 kt becoming southeast 10 to 15 kt in the afternoon. Sunny. Waves 1 to 3 ft. Thursday night..South winds 10 to 15 kt becoming north 15 to 25 kt after midnight. Slight chance of showers after midnight. Waves 1 ft or less building to 3 to 5 ft after midnight. | LMZ742 Expires:201804252145;;480350 FZUS53 KLOT 251447 NSHLOT NEARSHORE MARINE FORECAST National Weather Service Chicago/Romeoville IL 947 AM CDT Wed Apr 25 2018 For waters within five nautical miles of shore on Lake Michigan Waves are provided as a range of significant wave heights, which is the average of the highest 1/3 of the waves, along with the average height of the highest 10 percent of the waves which will occasionally be encountered. LMZ740>742-252145- |
7 Day Forecast for Marine Location Near Chicago, IL
Hourly EDIT Helplocation: 41.85, -87.6 debug
Area Discussion for - Chicago, IL
  (on/off)  Help NOTE: mouseover dotted underlined text for definitionFxus63 klot 251751 afdlot area forecast discussion national weather service chicago romeoville, il 1251 pm cdt Wed apr 25 2018 Update 1244 pm cdt have made only minor tweaks to hourly temp wind grids for the afternoon as the going forecast remains on track. Temps continue a slow rise well inland of the lake and highs around 60 are on track. Temps have leveled off in the chicago metro and areas near the lake so forecast highs in the 40s 50s look to be in good shape. Mdb Short term 207 am cdt through tonight... north winds have generally been gusting 20-30 mph with a few gusts to 35 mph behind a cold front crossing the CWA early this morning. This will continue into the daylight hours with an enhanced pressure gradient in place as weak troughing slowly exits central southern illinois. Expect these winds to ease slightly by this afternoon, then quickly diminish tonight as a weak surface ridge builds in from the west. A rather dry airmass per upstream raobs and satellite trends will supports sunny skies today with some passing cirrus and maybe a few cumulus clouds through early afternoon. Guidance has continued to show a slight cool-bias with sunny days over the past week, so have increased MAX temps a couple degrees away from the moderation of lake michigan. MAX temps today are expected to range from the upper 40s along the immediate shore to the low 60s well inland. Kluber Long term 228 am cdt Thursday through Tuesday... the long range features an upper air pattern shift and one to provide a stretch of warmer than normal days. It has been two months since we have had consecutive days with well above normal temperatures (10+ degrees), and even two months since some locations have had one! But that looks highly likely to end early next week. General northwest flow aloft into the weekend will shift west-southwesterly for next week. While some small rain shower chances late Thursday night, and possibly Friday evening, it looks mainly dry through Tuesday. High pressure will move over the area during the day Thursday, with a lake breeze anticipated. Thursday looks like a day with deep mixing and humidity could drop to 25 percent or less in some spots. A cold front will move through the area Thursday night. The best forcing for showers is to the north, but it is possible overnight some are seen in the cwa. The parent upper level feature, indicated by a strong vorticity maximum, drops southeast over the western great lakes Friday afternoon into the evening. This could support spotty showers, mainly in far northeast illinois into northwest indiana, with the better chance again to our northeast. Sunny and low humidity but light wind conditions are expected through the weekend. Upper ridging moves of the area later Sunday |
and the low-level thermal ridge to the immediate west of this ridge then spreads in for Monday. With gradual cyclogenesis across the rockies, and a strengthening surface high offshore of the southeast u.S., well-above normal temperatures are forecast to advect northeast between these features. Climatology for the 850 925 mb temperatures would support local highs well into the 70s, with low 80s in some areas probable by Tuesday and even Wednesday if no showers storms. Have collaborated warmer than the guidance blend during that time. These days look breezy too. Moisture should be on the increase especially by Tuesday, so fire weather concerns at this time look low, but may need to watch how quickly moisture returns on Monday. The setup favors convection across the plains into the upper mississippi valley during the first half of next week. Too far out to say timing for us midweek, but as the upper ridge begins to break down (sometime within Tue night - Thu given current forecast solutions), there will likely be thunderstorm chances. Mtf Aviation For the 18z tafs... tight pressure gradient remains in place but is loosening as surface ridging approaches. As a result, northeast winds remain breezy with gusts into the low 20s which will continue through the afternoon before easing up early this evening. High pressure will be overhead early Thursday allowing for much lighter winds which will favor a southwest direction away from the lake. Expect a lake breeze to develop but it is not clear how far inland across il it will make it before Thursday evening. Will keep it out of ord mdw for now. Winds will likely flip to the southeast Thursday evening but speeds will be light as this occurs. Otherwise,VFR will prevail. Mdb Marine 259 am cdt stout north winds today will gradually ease this afternoon and then rapidly this evening. High waves and hazardous conditions for small craft in the illinois and indiana nearshores will continue into this evening. After brief southwest winds on Thursday, another cold front will drop over the lake Thursday night with a push of north winds to 30 kt behind it. Yet another cold front will push through Friday night, though with weaker northerly winds behind it. Southerly winds will settle in on Sunday and be the rule into next week. Small craft advisory conditions are likely in the illinois and indiana nearshores during the days Monday-Wednesday with strong offshore winds. Mtf Lot watches warnings advisories Il... None. In... None. Lm... Small craft advisory... Il nearshore waters until 10 pm Wednesday. Small craft advisory... In nearshore waters until 1 am Thursday. Visit us at http: weather.Gov chicago (all lowercase) follow us on facebook... Twitter... And youtube at: |
Weather Reporting Stations
EDIT (on/off)  Help NOTE: Click on distance to see the station location on a mapStations | Dist | Age | Wind | Air Temp | Water Temp | Waves | Pressure | DewPt |
CNII2 | 1 mi | 13 min | N 13 G 17 | 45°F | 34°F | |||
OKSI2 | 4 mi | 133 min | N 12 G 16 | 42°F | ||||
CHII2 - Chicago, IL | 5 mi | 23 min | N 17 G 18 | 39°F | 35°F | |||
JAKI2 | 5 mi | 133 min | N 13 G 20 | 43°F | ||||
FSTI2 | 9 mi | 133 min | N 30 | 40°F | ||||
CMTI2 - 9087044 - Calumet, IL | 9 mi | 43 min | NNW 15 G 20 | 43°F | 1019.8 hPa | 36°F | ||
BHRI3 - Burns Harbor, IN | 28 mi | 33 min | NNW 17 G 19 | 39°F | 1020 hPa | |||
WHRI2 - Waukegan Harbor, IL | 37 mi | 33 min | NNE 17 G 19 | 39°F | ||||
MCYI3 - Michigan City, IN | 37 mi | 23 min | NW 20 G 21 | 40°F | 35°F |
Wind History for Calumet Harbor, IL
(wind in knots) EDIT (on/off)  Help1 PM | 2 PM | 3 PM | 4 PM | 5 PM | 6 PM | 7 PM | 8 PM | 9 PM | 10 PM | 11 PM | 12 AM | 1 AM | 2 AM | 3 AM | 4 AM | 5 AM | 6 AM | 7 AM | 8 AM | 9 AM | 10 AM | 11 AM | 12 PM | |
Last 24hr | N G12 | N G13 | N G13 | N G15 | N G10 | N | N G9 | NW G11 | N | N G8 | NW G11 | NW | NW G22 | NW G23 | NW G22 | NW G22 | NW G24 | NW G24 | NW | NW G23 | N G24 | NW G21 | N G24 | N |
1 day ago | N G18 | NW G21 | NW G20 | NW | NW G18 | N G11 | N G7 | NW | NW | N | N | N | N | N | N G9 | N | N | NW G9 | NW G9 | NW | NW G10 | N | NW G15 | NW G15 |
2 days ago | N | N G16 | N G18 | N G17 | N G16 | N G14 | N G14 | N G13 | N G11 | NE G12 | NE G13 | NE G9 | E | N | NE G8 | N | N | N G14 | N | N G15 | N G17 | N G17 | NW G18 | NW G19 |
Airport Reports
EDIT (on/off)  Help Click EDIT to display multiple airportsAirport | Dist | Age | Wind kt | Visibility | Sky/Weather | Temp | DewPt | Humidity | Pressure |
Chicago, Chicago Midway Airport, IL | 9 mi | 80 min | NNE 13 | 10.00 mi | A Few Clouds | 53°F | 32°F | 45% | 1019.9 hPa |
Chicago, Chicago-O'Hare International Airport, IL | 18 mi | 82 min | NE 14 | 10.00 mi | A Few Clouds | 51°F | 30°F | 45% | 1019.8 hPa |
Gary Regional Airport, IN | 19 mi | 88 min | N 16 | 20.00 mi | A Few Clouds | 45°F | 33°F | 66% | 1020 hPa |
Lansing Municipal Airport, IL | 22 mi | 78 min | N 9 G 16 | 10.00 mi | Fair | 46°F | 36°F | 69% | 1020 hPa |
Chicago / Wheeling, Pal-Waukee Airport, IL | 24 mi | 81 min | NNE 15 G 21 | 10.00 mi | Fair | 50°F | 30°F | 46% | 1020.5 hPa |
Wind History from MDW (wind in knots)
1 PM | 2 PM | 3 PM | 4 PM | 5 PM | 6 PM | 7 PM | 8 PM | 9 PM | 10 PM | 11 PM | 12 AM | 1 AM | 2 AM | 3 AM | 4 AM | 5 AM | 6 AM | 7 AM | 8 AM | 9 AM | 10 AM | 11 AM | 12 PM | |
Last 24hr | NE | N | NE | NE | N | NE | NE | NE | NE | N | N | N | N G19 | N | N G25 | N | N | N G21 | N G20 | N | N G23 | N | NE G21 | N |
1 day ago | N | NE | NE | NE | N | N | NE | E | NE | NE | N | Calm | NE | NE | N | E | NE | NE | NE | N | N | E | NE | N |
2 days ago | E | NE G22 | NE | NE | NE | NE | NE | NE | NE | NE | E | E | E | NE | E | NE | NE | NE | NE | NE | NE | NE | NE | NE |
Tide / Current Tables for
EDIT RT Ports Option Weekend mode (on/off) (on/off)  HelpTide / Current Tables for
EDIT (on/off)  HelpWeather Map and Satellite Images
(on/off)  HelpWeather Map
GOES Local Image of EDIT
NOTE: East coast views moved to GEOS-16. They are experimental and not well supported by NOAA so they may not be correct so be warned. This change required redoing a large amount of the GOES code. If the image you are expecting is not showing, please let me know. You may need to use the EDIT function to update your location.
target = "new">Link to Loop

Other links: Northern Pacific Contential US Full GOES-East
Wind Forecast for Chicago, IL (14,3,4,5)
(on/off)  Help![]() | ![]() | ![]() |
Ground Weather Radar Station Chicago, IL
(on/off)  HelpAd by Google
Disclaimer: The information on this web site has not been checked for accuracy. It is for entertainment purposes only and should be independently verified before using for any other reason. There are five sources. 1) Documents and manuals from a variety of sources. These have not been checked for accuracy and in many cases have not even been read by anyone associated with L-36.com. I have no idea of they are useful or accurate, I leave that to the reader. 2) Articles others have written and submitted. If you have questions on these, please contact the author. 3) Articles that represent my personal opinions. These are intended to promote thought and for entertainment. These are not intended to be fact, they are my opinions. 4) Small programs that generate result presented on a web page. Like any computer program, these may and in some cases do have errors. Almost all of these also make simplifying assumptions so they are not totally accurate even if there are no errors. Please verify all results. 5) Weather information is from numerious of sources and is presented automatically. It is not checked for accuracy either by anyone at L-36.com or by the source which is typically the US Government. See the NOAA web site for their disclaimer. Finally, tide and current data on this site is from 2007 and 2008 data bases, which may contain even older data. Changes in harbors due to building or dredging change tides and currents and for that reason many of the locations presented are no longer supported by newer data bases. For example, there is very little tidal current data in newer data bases so current data is likely wrong to some extent. This data is NOT FOR NAVIGATION. See the XTide disclaimer for details. In addition, tide and current are influenced by storms, river flow, and other factors beyond the ability of any predictive program. |