Thursday, June22, 2017 L-36.com


Marine Weather and Tides
North Chicago, IL

Version 3.4
What's New / NOTES
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 5:13AMSunset 8:33PM Thursday June 22, 2017 3:30 PM CDT (20:30 UTC) Moonrise 4:09AMMoonset 6:54PM Illumination 2% Phase: Waning Crescent; Moon at 28 days in cycle
NOTE: Some of the data on this page has not been verified and should be used with that in mind. It may and occasionally will, be wrong. The tide reports are by xtide and are NOT FOR NAVIGATION.
Marine Forecasts
    EDIT      (on/off)   Help
LMZ740 Winthrop Harbor To Wilmette Harbor- Wilmette Harbor To Northerly Island- Northerly Island To Calumet Harbor- 901 Am Cdt Thu Jun 22 2017
.small craft advisory in effect until 7 pm cdt this evening...
Rest of today..Southwest winds increasing to 20 to 25 kt. Partly Sunny. Waves 1 to 3 ft.
Tonight..South winds 15 to 20 kt becoming southwest after midnight, then northwest late. Slight chance of showers and Thunderstorms in the evening, then showers and Thunderstorms likely after midnight. Waves 2 to 4 ft.
Friday..Northwest winds 10 to 15 kt. Slight chance of showers in the morning. Waves 1 to 3 ft.
Friday night..Northwest winds 10 to 20 kt. Partly cloudy. Waves 1 to 3 ft building to 2 to 4 ft after midnight.
LMZ740 Expires:201706222200;;638924 FZUS53 KLOT 221401 NSHLOT NEARSHORE MARINE FORECAST National Weather Service Chicago/Romeoville IL 901 AM CDT Thu Jun 22 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>742-222200-

7 Day Forecast for Marine Location Near North Chicago, IL
   Hourly   EDIT   Help
location: 42.35, -87.79     debug


Area Discussion for - Chicago, IL
      (on/off)   Help   NOTE: mouseover dotted underlined text for definition
Fxus63 klot 221947 cca
afdlot
area forecast discussion... Corrected
national weather service chicago romeoville, il
247 pm cdt Thu jun 22 2017

Short term
225 pm cdt
through Friday...

concerns center around isolated thunderstorm development this
afternoon, and then with a line of storms late this evening and
overnight.

Inhibition gradually continues to erode from the south generally
driven by low level moisture advection soundings. Amdar soundings
still depict some decent capping thanks to fairly warm
temperatures in the 800-700 mb layer, at least closer to chicago
the hrrr now has backed off a bit on the coverage for the
afternoon and early evening, consistent with very little weak
convergence in place and a lack of a larger scale forcing
mechanism. But there is some weak upper forcing pushing in from
the south, thus we maintain an isolated shower and storm mention
for the afternoon early evening. Shear profiles are still fairly
weak during this period thus severe threat is low.

We will hang onto instability through the evening ahead of the
cold front currently draped across the northern plains upper
midwest. Stronger upper level winds will approach the area along
the southern fringes of the upper low across manitoba. Clusters of
storms will continue to develop along and ahead of the front. Any
storms that area able to get going this evening ahead of the front
will form in an axis of 1000+ j kg of MLCAPE and shear in excess
of 30 kt, which keep the threat of hail or locally damaging winds,
mainly across north central il this evening, especially if
anything forms upstream and develops a cold pool while pushing
ahead into the continued unstable airmass. The cold front will
pass through the chicago area after midnight, with the line of
storms passing southeast with it. There are some waves in the
southwest flow aloft that may initially slow the progression of
the front before it gets shoved southeastward late tonight, and
may prevent a solid line, but confidence is pretty high in many
areas seeing some activity. Moisture pooling ahead of the front
would suggest at least some brief heavy downpours in this
scenario, while the more significant flood threat is largely just
to our north northwest.

Quite the airmass change will filter air on Friday, with much
drier air across the upper midwest (note the 40s tds in mn). These
will not get here that quickly but eventually will get in here
this weekend. Still humidity levels will be much lower, and temps
look to top off in the upper 70s to near 80. It may be a bit
cooler along the in shore. Showers and storms look to still be
ongoing tomorrow morning, but guidance is in good agreement of
getting the front through in the afternoon.

Long term
238 pm cdt
Friday night through Thursday...

for the longer term forecast period, general trends remain
consistent with previous runs and the short term forecast period
trends.

By Friday night, the longwave pattern will be trending toward a
higher amplitude with building ridging over the west coast and broad
troughing over the ERN 2 3 of the conus. The broad upper trough
will help contribute to a period of below normal temperatures for
the weekend through early next week. The local area will be under
fast nwly flow aloft, with a series of NRN stream shortwaves
dropping through the nwly flow, sharpening the upper trough and
generating sct showers. Chances for thunderstorms will be low,
though not out of the question for the afternoon hours. The highest
chance for any pcpn through the weekend will likely be Sunday
afternoon into Sunday evening when a stronger shortwave is expected
to drop through the upper mississippi valley and across the upper
great lakes. There are some strength differences noted in the
longer range guidance, with the ECMWF trending stronger than the
gfs gem, though all indicate similar timing. So, will carry chance
pops for the NRN portions of the CWA with some scattered
thunderstorms possible. Any pcpn should be scattered, so the day
should not be a washout. Temperatures for the weekend through early
next week will be below normal, with highs only in the lower 70s
through Monday. With high pressure associated with a dry continental
polar air mass sliding out of canada and across the cntrl plains and
mississippi valley, dewpoints will also be anomalously low for late
june and should only be in the upper 40s to around 50 f.

By Tuesday, the upper ridge is still expected to build east across
the rockies and out over the cntrl CONUS while sfc high pressure
shifts to the east coast. Rising heights aloft and increasingly sly
flow at the sfc will set up a return flow of warm moist air with
temps reaching the upper 70s for Tuesday and the lower 80s for
midweek. Dewpoints should also be on the rise back into the upper
50s to lower 60s.

Aviation
For the 18z tafs...

concerns center around isolated thunderstorm development this
afternoon, and then with a line of storms late this evening and
overnight. MVFR lowVFR clouds will also spread in from the south
through the afternoon and evening. Concern regarding winds
shifting to nnw-n, to possibly nne at ord mdw just behind the
front.

A continuous stream of MVFR or lowerVFR clouds will advect
northward through the afternoon and evening. Guidance suggests
this may briefly come in MVFR and settle toVFR before becoming
predominant MVFR ahead of the cold front tonight.

Convection continues to weaken off to the northwest. There is a
weak convergence axis over northeast il that may trigger a shower
or two that may become a storm as inhibition erodes. Confidence is
too low on coverage to include in the TAF set, as the forcing is
subtle, but will need to monitor. Better chances storms comes
tonight. High confidence in a line of storms moving with the cold
front, with some weakening trend likely after passing the chicago
terminals. Current rap hrrr timing is just slightly later than
previous runs, but 6-7z timing in an around the chicago terminals
seems reasonable. There could be some prefrontal showers or
thunderstorms after 3-4z as well, but confidence is low on this.

Winds may abruptly shift to N or even NE with the front at ord mdw
but look to settle back to NW through the morning. MVFR clouds
lift behind the front.

Kmd

Marine
245 pm cdt
the low over western manitoba will weaken as it crosses ontario
tonight and then continues to quebec Friday. An associated cold
front will sweep across the lake tonight into early Friday
morning with winds becoming west to northwest behind the front.

Westerly winds are expected to continue through early next week.

High pressure should then build in behind the exiting cold front,
spreading across the plains Sunday and the western great lakes
early next week, setting up a period of relatively light and
variable winds. As the high shifts to the east and new low
pressure develops over the northern plains, winds will trend more
southerly and strengthen to arnd 15 to 20 kt by Tuesday. A
strengthening southerly pressure gradient could bring winds up to
30 kt by mid week as high pressure remains parked over the sern
conus and the trough and associated cold front track east across
the plains.

Lot watches warnings advisories
Il... None.

In... None.

Lm... Small craft advisory... Nearshore waters
until 7 pm 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 map
Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
WHRI2 - Waukegan Harbor, IL 1 mi50 min SSW 13 G 21 83°F
45174 16 mi20 min SW 12 G 14 79°F 65°F2 ft67°F
KNSW3 - Kenosha, WI 17 mi30 min SSW 9.9 G 19 85°F 1007.5 hPa (-1.3)
FSTI2 27 mi90 min SSW 29 86°F
OKSI2 32 mi90 min WNW 2.9 87°F
CHII2 - Chicago, IL 32 mi40 min SSW 12 G 13 83°F 69°F
45177 33 mi150 min 65°F
CNII2 35 mi15 min 87°F
JAKI2 41 mi90 min WSW 12 87°F
CMTI2 - 9087044 - Calumet, IL 45 mi42 min S 11 G 13 86°F 1008.1 hPa71°F
45007 - S MICHIGAN 43NM East Southeast of Milwaukee, WI 46 mi40 min SSW 9.7 G 9.7 66°F 61°F2 ft1008.6 hPa (-0.4)64°F
MLWW3 - Milwaukee, WI 48 mi40 min W 4.1 G 6 81°F

Wind History for Calumet Harbor, IL
(wind in knots)    EDIT      (on/off)   Help
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
1
PM
2
PM
Last
24hr
NE8
NE6
G9
E9
E6
E4
E4
NE3
E4
E4
SE1
SE6
S6
G9
S7
G10
S11
G16
SW10
G15
SW6
G10
S8
G13
SW7
G11
S9
G13
SW12
G15
SW8
G16
S12
G16
S12
G18
S7
G11
1 day
ago
N12
G16
N13
G16
E9
E12
G15
E7
E3
--
N5
E5
SE1
NW1
NW2
N2
NE2
N3
--
NE5
NE4
NE5
E4
NE5
G8
NE8
NE7
G11
NE9
2 days
ago
W7
G17
NW5
G9
N7
G12
S1
--
SW3
SW5
SW5
SW6
SW4
SW4
SW3
SW3
SW5
SW4
G7
SW3
SW2
SW7
G10
SW5
G9
SW9
G15
SW7
G12
SW10
G15
SW6
G11
N8
G13

Airport Reports
    EDIT      (on/off)   Help   Click EDIT to display multiple airports
AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Chicago/Waukegan Regional Airport, IL6 mi35 minSW 12 G 2110.00 miPartly Cloudy86°F69°F57%1006.6 hPa
Chicago / Wheeling, Pal-Waukee Airport, IL18 mi38 minSSW 1210.00 miFair86°F71°F61%1008 hPa
Kenosha, Kenosha Regional Airport, WI18 mi37 minWSW 1210.00 miFair85°F66°F53%1007.3 hPa

Wind History from UGN (wind in knots)
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
1
PM
2
PM
3
PM
Last 24hrSE7SE8SE6SE6SE5SE5SE4E3SE4S6S7S6S11SW11SW13
G20
SW7SW9
G17
SW12
G16
SW13SW12SW14
G20
SW14
G22
SW11SW12
G21
1 day agoE5S8CalmNE3S4NW3W3CalmCalmSW3CalmCalmCalmW3CalmSW3Calm4SE7SE7SE8SE8SE8E7
2 days agoN534Calm53W443W3W3CalmCalmSW33SW754W8
G17
56NW4NE14
G25
NE9
G21

Tide / Current Tables for
   EDIT   RT Ports Option   Weekend mode (on/off)   (on/off)   Help
Tide / Current Tables for
   EDIT      (on/off)   Help
Weather Map and Satellite Images
       (on/off)   Help
Weather Map
wmap_A
IR Satellite Image from GEOS
east_satellite

GOES Local Image of Midwest    EDIT
Geos

Wind Forecast for Chicago, IL (16,3,4,5)
      (on/off)   Help

Ground Weather Radar Station Chicago, IL
   (on/off)   Help
weather_mapweather_map weather_map

Ad 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.