Marine Weather and Tides
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.
5/19/2016 - There were issues with the 3 day airport observation history. I switched to another data source. Let me know if you see any issues with the data feeds.
|Sunrise 6:42AM||Sunset 6:41PM||Tuesday September 26, 2017 1:15 PM CDT (18:15 UTC)||Moonrise 12:51PM||Moonset 10:48PM||Illumination 36%|
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|LMZ741 Winthrop Harbor To Wilmette Harbor- Wilmette Harbor To Northerly Island- Northerly Island To Calumet Harbor- 916 Am Cdt Tue Sep 26 2017 |
Rest of today..Southwest winds 10 to 15 kt. Partly cloudy, with a slight chance of showers in the afternoon. Waves 1 ft or less.
Tonight..Northwest winds 10 to 15 kt increasing to 15 to 20 kt after midnight. A few gusts to 25 kt. Slight chance of showers in the evening. Waves 1 ft or less building to 2 to 4 ft after midnight.
Wednesday..North winds 15 to 20 kt. Mostly Sunny. Waves 3 to 5 ft subsiding to 2 to 4 ft in the afternoon.
Wednesday night..North winds 10 to 20 kt. Mostly clear. Waves 2 to 4 ft.
|LMZ741 Expires:201709262145;;961385 FZUS53 KLOT 261416 NSHLOT NEARSHORE MARINE FORECAST National Weather Service Chicago/Romeoville IL 916 AM CDT Tue Sep 26 2017 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>742-262145-|
7 Day Forecast for Marine Location Near North Riverside, ILHourly EDIT Help
Area Discussion for - Chicago, IL  (on/off)  Help NOTE: mouseover dotted underlined text for definition
|Fxus63 klot 261717|
area forecast discussion
national weather service chicago romeoville, il
1217 pm cdt Tue sep 26 2017
Update 1128 am cdt
one last day of record near record temps appears a go. Ord is 87
and mdw is 89 as of 1130 am one minute obs. With scattered clouds
and southwest winds we should be able to at least tag the 90
degree mark, the current record at ord. Expect increasing clouds
in the afternoon ahead the approaching cold front.
325 am cdt
one more day - this week - of temperatures making a solid run to
near record levels mainly for locations along and east of i-55.
There remains a minimal chance for isolated showers today and
this evening, but overall forcing for any storms high impact
weather looks low.
The main cold front this morning is draped from western wisconsin
through kansas city and slowly inching eastward. Outflow emanating
from showers last night reached northwest north central illinois,
triggering a few showers. Spotty light showers could pop in this
same area into the morning as 20-25 kt south-southwest flow
continues over the old outflow.
The challenge with temperatures today will be clouds. Early
morning satellite imagery depicts high clouds spreading over
northern illinois. Some of this looks to thin later this morning
into early afternoon before re-increasing later, although
predicting mid-high cloud trends is challenging. The approach of
the boundary and increasing precipitable waters to 1.5 inches
should mean some off and on high clouds for the forecast area
today, with north central illinois likely seeing more clouds than
sun. Warm advection areawide and a mild starting point will allow
temperatures to at least reach well into the 80s, and eastern
locations if enough Sun will have a fair chance to reach 90 given
low-level thermal profiles. Boundary layer southwest wind speeds
should be enough to prevent lake breeze cooling today, so
lakefront areas including downtown chicago should see just as warm
As the front moves through the area later today and early this
evening, isolated showers along the general convergence zone are
possible. Ahead of the front in eastern areas, afternoon
temperatures may reach the convective temperatures, but will
depend on dew points. Cannot rule out a stray earlier shower, but
the best chance... Which is still quite low... Should be along the
boundary. Thunder chances are even lower given the general
synoptic pattern of clouds shielding the convergence zone as well
as weak elevated lapse rates.
Northwest winds will pick up some tonight behind the front
steering in gradually cooler and drier air.
325 am cdt
Wednesday through Monday...
noteworthy items for this part of the forecast are another cold
front moving through late Thursday night with a more seasonable
shot of air, but that looks quite brief with increasing potential
for another warm-up into the first week of october.
Northwest winds of 10-15 mph will filter in cooler air on
Wednesday. Morning cloud cover looks to ease in the afternoon due
to a stout subsidence inversion and drying. Lake effect
stratocumulus, at least patches, are likely into northwest
indiana. Both Wednesday and Thursday should see highs in the
lower-mid 70s for most.
A strong upper short wave trough will drop southeast over ontario|
and the great lakes region Thursday night into Friday. Looking at
the model trend of this, it has been further northeast in global
solutions in the past 24 hours. For our area, that means even less
chance for any rain with the system's cold front, as well as a
quicker passage of the cool air.
Friday looks breezy behind the cold front with lake effect
stratocumulus very likely into northwest indiana and possibly
northeast illinois. Moisture depths are shallow, but some
sprinkles or light showers may need to be added to lakeside areas.
Highs are forecast to fall short of 70 in northern areas Friday
and for most on Saturday. Depending on precise high placement,
Friday and Saturday nights should see decent radiational cooling.
Some outlying favorable locations could dip into the upper 30s if
dew points are low enough.
Global solutions are trending warmer for at least the first half
of next week, with upper ridging building back into the area. The
forecast pattern on both the 00z GFS and emcwf, as well as the
locally dry ground and increased sensible heat flux, could favor
highs reaching or topping 80 already by Monday.
For the 18z tafs...
concerns are on shower development ahead of an approaching cold
front, along with maybe a thunderstorm mainly along the western
terminals. There is some chance for MVFR CIGS behind the front
In spite of a decent cold front that will move through this
evening, upper level forcing for precipitation is fairly weak, and
will be the strongest west of the chicago terminals. Therefore
expect the shower activity across iowa to move with the front, but
likely diminish in coverage. Rfd does stand a smaller chance of
thunderstorm, but the window appears small and short lived and
thus we have held the vcsh mention instead of vcts. Expect a
northwest wind shift with the front, with occasional gusts into
the mid teens before they settle to around 10 kt or so. MVFR
ceilings could briefly occur overnight, and there may be some weak
showers, but again very low coverage.VFR will dominate much of
Wednesday on continued northwest wind.
325 am cdt
a cold front passage tonight will end the quieter marine weather,
at least temporarily. Winds will turn northwest behind the front
and increase in speed with gusts around or a little above 25 kt
for much of the open water. A small craft advisory will be needed
for Wednesday along the indiana nearshore for winds and waves and
possibly the illinois nearshore for winds. Winds and waves will
ease some Wednesday night and early Thursday.
A second and more stout cold front will move south across the lake
on Thursday night. This will bring northwesterly 30 kt gusts for
the open water for Friday, and these winds will turn more toward
due north by Friday evening it appears. This means quickly building
waves for the indiana nearshore by Friday morning and the illinois
nearshore shortly after. Winds and waves look to diminish by
Saturday morning or early afternoon at this time.
Lot watches warnings advisories
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Weather Reporting StationsEDIT (on/off)  Help NOTE: Click on distance to see the station location on a map
|Stations||Dist||Age||Wind||Air Temp||Water Temp||Waves||Pressure||DewPt|
|CNII2||11 mi||16 min||SSW 9.9 G 18||88°F|
|OKSI2||12 mi||136 min||WNW 1.9||89°F|
|FSTI2||13 mi||136 min||SSW 11||88°F|
|JAKI2||14 mi||136 min||WSW 9.9||87°F|
|CHII2 - Chicago, IL||14 mi||26 min||SW 19 G 23||87°F||61°F|
|CMTI2 - 9087044 - Calumet, IL||17 mi||46 min||S 8.9 G 12||87°F||1013.6 hPa||63°F|
|45174||22 mi||26 min||SW 9.7 G 14||81°F||73°F||1 ft||66°F|
|WHRI2 - Waukegan Harbor, IL||36 mi||36 min||S 8.9 G 12||81°F|
|BHRI3 - Burns Harbor, IN||38 mi||36 min||SW 13 G 16||85°F||1014.6 hPa|
|45170||46 mi||26 min||SSW 1.9 G 3.9||80°F||73°F||68°F|
|MCYI3 - Michigan City, IN||49 mi||26 min||SW 9.9 G 11||84°F||60°F|
Wind History for Calumet Harbor, IL(wind in knots) EDIT (on/off)  Help
Airport ReportsEDIT (on/off)  Help Click EDIT to display multiple airports
|Chicago, Chicago Midway Airport, IL||5 mi||23 min||WSW 15||10.00 mi||Partly Cloudy||90°F||60°F||37%||1012.5 hPa|
|Chicago, Chicago-O'Hare International Airport, IL||11 mi||25 min||SW 10 G 18||10.00 mi||Partly Cloudy||89°F||61°F||39%||1012.9 hPa|
|Chicago / Wheeling, Pal-Waukee Airport, IL||19 mi||24 min||WSW 8 G 16||10.00 mi||A Few Clouds||91°F||63°F||39%||1013.3 hPa|
|Lewis University Airport, IL||22 mi||41 min||SSW 14 G 18||10.00 mi||Fair||89°F||61°F||39%||1014.6 hPa|
|Chicago / West Chicago, Dupage Airport, IL||24 mi||24 min||SW 12 G 19||8.00 mi||A Few Clouds||89°F||63°F||42%||1013.2 hPa|
Wind History from MDW (wind in knots)
|1 day ago||S||S||SE||E||E||E||E||E||SE||Calm||S||S||S||S||S||S||S||S||S||S||S||S||SE||Calm|
|2 days ago||SE||E||E||E||E||E||E||E||E||E||E||SE||SE||SE||SE||S||S||S||S||S||SW||SW||SW||S |
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Weather Map and Satellite Images(on/off)  Help
|Weather Map ||IR Satellite Image from GEOS|
GOES Local Image of Midwest EDIT
Wind Forecast for Chicago, IL (14,3,4,5)(on/off)  Help
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