Marine Weather and Tides
5/20/2018 -- NOAA is having problems with the data feed that I use to draw the graphs. They are aware of the issue and working to resolve it. Sometimes changing the location by about a mile will give a correct graph. 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.
|Sunrise 5:19AM||Sunset 8:16PM||Friday May 25, 2018 11:23 PM CDT (04:23 UTC)||Moonrise 4:17PM||Moonset 3:33AM||Illumination 86%|
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|LMZ741 Winthrop Harbor To Wilmette Harbor- Wilmette Harbor To Northerly Island- Northerly Island To Calumet Harbor- 909 Pm Cdt Fri May 25 2018 |
Rest of tonight..Southwest winds 5 to 15 kt. Mostly cloudy. Waves 1 ft or less.
Saturday..South winds 5 to 10 kt becoming southeast in the afternoon. Slight chance of showers and Thunderstorms in the afternoon. Waves 1 ft or less.
Saturday night..Southeast winds 5 to 10 kt becoming southwest after midnight. Mostly clear. Waves 1 ft or less.
Sunday..Southwest winds around 5 kt becoming southeast in the afternoon. Sunny. Waves 1 ft or less.
|LMZ741 Expires:201805261015;;533311 FZUS53 KLOT 260209 NSHLOT NEARSHORE MARINE FORECAST National Weather Service Chicago/Romeoville IL 909 PM CDT Fri May 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>742-261015-|
7 Day Forecast for Marine Location Near Evanston, ILHourly EDIT Help
Area Discussion for - Chicago, IL  (on/off)  Help NOTE: mouseover dotted underlined text for definition
|Fxus63 klot 260134|
area forecast discussion
national weather service chicago romeoville, il
834 pm cdt Fri may 25 2018
834 pm cdt
pattern far more reminiscent of mid-summer than may with weak
synoptic forcing convection largely being driven by mcvs. One
weakening MCV from last night's convection is supporting a small
cluster of showers a couple t-storms across east central il,
including our far southern cwa. This activity is likely to weaken
over the next couple hours, likely dissipating by midnight as it
encounters drier and more stable air mass.
Upstream over NE ia and SW wi another area of convection has begun
to show some signs of mesoscale organization, with a qlcs bowing
toward se. The evening sounding from dvn sampled a modestly
unstable environment with CAPE around 1000 j kg, however boundary
layer is currently cooling and atmosphere is beginning to
stabilize. Could see another MCV develop in the bookend of this
developing bow, which could augment the weak ambient shear
environment and help this activity sustain itself as it pushes
into NW il mid-late this evening. Would generally expect a
weakening trend, particularly with the eastern extent of this line
as it encounters a more stable and worked over air mass. Goes-16
1-min IR imagery has shown a tendency for warming cloud tops and
weakening of the convection over SW wi and some cooling cloud tops
(intensification) over ia where instability is greater. Will
likely be a bit of battle of opposing forces the next several
hours as instability axis over eastern ia would tend to support
more of a southward propagation of this convection, while current
storm motion and the development of a MCV would tend to favor more
of a SE motion toward our cwa.
At this point, planning to increase pops far western CWA late this
evening to account for this activity potentially spreading in.
However, given the weaker instability in our area, suspect the
threat of more robust storms should remain west of our cwa, though
certainly lightning and heavy downpours look quite possible.
253 pm cdt
scattered shower and thunderstorm trends are the main forecast
concerns through this evening, with continuation of very warm
summer-like weather persisting into the holiday weekend.
Early afternoon surface analysis depicts weak low pressure over
western il, along a pseudo-warm front extending from along the
mississippi river into far southern il. This weak low, and an area
of thunderstorms over western il, were associated with a mid-
level short wave trough propagating across the region. The primary
low level focus for storms appears to be the warm frontal trough,
further enhanced by differential heating due to cloud cover, and
convective outflow. These storms should continue to move slowly to
the east-northeast across the forecast area through the remainder
of the afternoon and early evening hours, though instability
gradually decreases farther east. This, combined with weak mid-
level lapse rates and weak deep-layer shear, should allow for a
general decrease in intensity and coverage with eastward extent
into early evening as diurnal instability diminishes with sunset.
While SPC has stretched the day 1 marginal severe risk east to the
il in border, overall lack of deep shear and warm thermal
profiles should preclude much of a severe threat, with the main
concern being the potential for isolated wind gusts. Locally heavy
rainfall is likely a greater threat, given slow cell movements
and p-wats approaching 1.80".
High-res cam guidance continues to indicate some potential for
storms currently developing over southeastern mn to develop
southeastward into parts of northwest north central il after
midnight tonight. Forecast soundings, especially from the nam,
suggest substantial elevated CAPE may be present over northwest il
during the early overnight hours, though veering of the h8 winds
and overall lack of deep shear suggests that storms may struggle
to push too far south. 3km wrf, hrrr and arw runs all weaken these
storms as they spread into il during the pre-dawn hours, and have
generally limited mention to low chance pops for these.
Primary mid-level trough passes across the region early Saturday,
with weak height rises developing during the day. While low level
wind fields turn light westerly behind the trough, air mass
remains very warm and moist. While no significant forcing is|
noted, an isolated shower or thunderstorm can't be ruled out
during the peak heating hours of the afternoon where weak low
level convergence of subtle mid-level vort may interact, however
most areas will likely remain dry. With at least partly sunny
conditions, temps should again reach the upper 80's around 90
degrees, with a weak lake breeze likely keeping areas along the
immediate lake michigan shore a little cooler.
231 pm cdt
Saturday night through Friday...
surface high pressure will be across the area Saturday night
while upper ridging to the west slides into the area into Sunday
night. Overnight lows will remain warm with mid and upper 60s
while the heart of the chicago metro see lows around 70, if not
warmer. With the upper ridge pushing in Sunday low and mid level
warming peaks with 850 mb temps around 20c. This supports low 90s
with a few mid 90s possible given that sunshine should be
abundant. Limiting factor from reaching mid 90s may be weak low
level winds. This weak flow will also allow a lake breeze to
develop which should provide some relief from the hottest temps
near the lake. Main question will be how high temps peak before
some modest cooling into the mid upper 80s in the afternoon. Peak
heat index values should be around 95 away from the lake. The
upper ridge broadens for Monday with surface high pressure still
in place so may not see much change from Sunday and may need to
bump high temps up a couple degrees similar to the forecast for
Sunday. Expect either a weak easterly flow on the west side of the
high or a lake breeze to develop keeping lakeshore areas cooler.
The upper ridge starts shifting east Tuesday and an upper trough
will move east across the northern plains. The current sub
tropical low is expected to move into the gulf coast states by
Wednesday will have an impact on pattern evolution and may phase
the northern plains trough. Quiet a few things need to occur
before mid week so confidence in details is low but the area may
get into some precip chances as early as Tuesday and could
continue through mid week. Am fairly confident that a warm
pattern, though not as warm as the next few days, will continue
with highs generally in the 80s. The pattern may favor an easterly
flow or lake breeze development so lakeshore areas look to be
cooler through much of the week.
For the 00z tafs...
vfr conditions expected through the forecast period. S SW winds
will remain generally under 10kts at all sites. A weak lake breeze
should pass ord mdw late Saturday afternoon into the early
evening. At rfd, a cluster of tsra currently over far southeast mn
is expected to remain just west of the terminal, but a few showers
may brush the terminal between 03-07z.
231 pm cdt
south to southwest winds will prevail across the open waters
through the weekend with the strongest winds occurring into this
evening. A weaker flow pattern will allow winds to ease Saturday
and Sunday and will also favor the development of onshore flow
across the illinois and indiana nearshore waters each day. A weak
front drops down the lake later Monday bringing at least a
temporary shift to northeasterly flow. After that the pattern
becomes less certain with the sub tropical system currently off
the yucatan peninsula moving into the gulf coast states early next
week. This may interact with a trough moving across the northern
plains but this is not certain. Do not foresee any major wind
producing systems affecting the lake but wind speed and direction
details from Tuesday onward may change.
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|
|FSTI2||4 mi||143 min||WNW 8||79°F|
|45174||7 mi||33 min||WSW 3.9 G 5.8||70°F||56°F||1 ft||64°F|
|OKSI2||9 mi||143 min||WNW 1 G 2.9||81°F|
|CHII2 - Chicago, IL||10 mi||33 min||SSW 18 G 19||74°F||64°F|
|CNII2||13 mi||23 min||S 7 G 12||76°F||63°F|
|JAKI2||18 mi||143 min||W 2.9 G 4.1||80°F|
|CMTI2 - 9087044 - Calumet, IL||22 mi||53 min||WSW 8 G 12||70°F||1009.5 hPa||65°F|
|WHRI2 - Waukegan Harbor, IL||24 mi||43 min||WSW 4.1 G 6||76°F|
|BHRI3 - Burns Harbor, IN||39 mi||43 min||S 8.9 G 12||76°F||1009.5 hPa|
|KNSW3 - Kenosha, WI||39 mi||83 min||77°F||1008.5 hPa (+0.7)|
|45170||43 mi||33 min||WSW 7.8 G 12||70°F||61°F||1 ft||62°F|
|MCYI3 - Michigan City, IN||46 mi||33 min||S 21 G 24||78°F||58°F|
Wind History for Calumet Harbor, IL(wind in knots) EDIT (on/off)  Help
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|Chicago / Wheeling, Pal-Waukee Airport, IL||12 mi||31 min||SW 4||10.00 mi||A Few Clouds||78°F||64°F||64%||1008.6 hPa|
|Chicago, Chicago-O'Hare International Airport, IL||12 mi||32 min||SW 9||10.00 mi||Overcast||77°F||64°F||64%||1008.3 hPa|
|Chicago, Chicago Midway Airport, IL||17 mi||30 min||SW 6||10.00 mi||Overcast||76°F||66°F||72%||1008.1 hPa|
Wind History from PWK (wind in knots)
|1 day ago||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||S||S||S||S|
|2 days ago||Calm||S||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||SE||E||SE||E||E||E||NE||E||Calm||E |
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GOES Local Image of Midwest 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.
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Wind Forecast for Chicago, IL (0,6,7,8)(on/off)  Help
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