Saturday, February27, 2021
Privacy Policy
L-36.com

Marine Weather and Tides
Evanston, IL

Version 3.4
NOTICE
1/26/2021 -- The West Coast Satellite images havd been updated. They now use GEOS-17.
1/1/2021 -- The 7 day forecast are now working well. Thank you NOAA for your support.

Sunrise 6:26AMSunset 5:40PM Saturday February 27, 2021 3:59 PM CST (21:59 UTC) Moonrise 7:11PMMoonset 8:03AM Illumination 99% Phase: Waning Gibbous; Moon at 16 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
LMZ741 Expires:202102280415;;216611 Fzus53 Klot 272059 Nshlot Nearshore Marine Forecast National Weather Service Chicago/romeoville Il 259 Pm Cst Sat Feb 27 2021 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>742-280415- Winthrop Harbor To Wilmette Harbor- Wilmette Harbor To Northerly Island- Northerly Island To Calumet Harbor- 259 Pm Cst Sat Feb 27 2021
.small craft advisory in effect from Sunday afternoon through Sunday evening...
Tonight..South winds 10 to 15 kt becoming southeast in the evening and then east after midnight. Areas of fog after midnight. Chance of showers and patchy drizzle after midnight. Waves 1 ft or less building to 2 to 4 ft.
Sunday..Southeast winds 10 to 15 kt becoming southwest 15 to 20 kt by the late morning and west to 30 kt in the afternoon. Occasional gale force gusts possible in the mid to late afternoon. Areas of fog in the morning. Chance of showers and patchy drizzle in the morning. Waves 2 to 4 ft.
Sunday night..Northwest winds to 30 kt becoming west 10 to 20 kt after midnight. Mostly clear. Waves 2 to 4 ft subsiding to 1 to 3 ft after midnight.
Monday..West winds 10 to 20 kt becoming north 15 to 25 kt in the afternoon. Sunny. Waves 1 to 3 ft building to 3 to 5 ft in the afternoon.
LMZ741


7 Day Forecast for Marine Location Near Evanston, IL
   Hourly   EDIT   Help
location: 42.03, -87.69     debug


Area Discussion for - Chicago, IL
      (on/off)   Help   NOTE: mouseover dotted underlined text for definition
FXUS63 KLOT 272121 AFDLOT

Area Forecast Discussion National Weather Service Chicago/Romeoville, IL 321 PM CST Sat Feb 27 2021

SHORT TERM. 240 PM CST

Through Sunday night .

The 50 isotherm has worked its way north into the CWA today, with Chicago officially reaching that mark. After the harsh wintry conditions of early to mid February, this and the sun are welcome by many. It's actually the latest first 50 in a calendar year since 2015, which was coming out of the coldest February in Chicago in over a century. Mild weather sticks around through early afternoon Sunday before temperatures fall. Concerns in the short term are centered on the potential for dense fog returning late tonight and Sunday morning and then westerly wind gusts to 35 to 40 mph Sunday afternoon.

Sun prevails across much of the CWA this afternoon with the snow cover free areas generally in the lower to mid 50s and the deeper snow covered areas in the upper 30s to mid 40s. A strong southwesterly upper jet of 130+ kt is traversing over the area between a developing downstream upper ridge and a trough moving into the Upper Midwest. This jet will send thicker cirrus our way this evening. Depending on how quickly this moves in, temperatures may drop quickly in the first couple hours after sunset. After that point, thickening clouds and gradually increasing southeast flow should flat-line temperatures and likely result in an overnight gradual climb. The exception would be near the lake and including downtown Chicago where a more easterly wind will likely hold temperatures in the mid 30s.

The Upper Midwest trough will deepen on the aforementioned jet, resulting in gradually increasing mass response within the lower troposphere, namely moisture advection. As the isentropic ascent also increases, the moist layer deepens to the point where likely some drizzle and pockets of rain will be spreading northward overnight. In addition, a low amplitude short wave will move from eastern Oklahoma this afternoon to central Indiana late tonight, with forcing for showers spreading across the southeast forecast area. There is positive MUCAPE of a couple hundred J/kg knocking on the door to the southern CWA on several model solutions, including the 12Z HREF. Lapse rates become pretty mushy quickly with northward extent though, so have not mentioned any thunder at this time. Scattered showers may be experienced further north in the CWA late tonight into Sunday morning.

In tandem with and in part due to the increasing moisture, today's snow melt and sublimation will further add to the boundary layer moisture. This likely was fairly effective today in adding moisture based on the trend in 24-hour snow density observations -- basically all of the moisture had worked its way down into the remaining few inches of snow and that is now melting. With the warm/moist advection regime favoring an advection fog, feel that at least areas of fog are a reasonable forecast trend. Given the conditions observed this morning and with much higher dew points (35-40+) moving northward tonight, certainly feel dense fog may blossom. The easterly onshore flow into Chicago into early Sunday morning would likely further help the potential for dense fog there too. A hindrance to dense fog developing could be the aforementioned showers.

The southerly flow into the morning and the increasing warm/moist advection will force surface temperatures upward. Would expect some southern CWA locations to be near or even 50 by 8 A.M. Sunday morning. This warmth will inch its way northward, probably getting a brief surge late in the morning/early in the afternoon when winds temporarily turn southwest ahead of the system cold front. Could definitely see 60 reached in the southern CWA as the 12Z ECMWF is advertising.

With the rate of cyclogenesis yielding the surface low to deepen to below 1000 mb near Sault Ste. Marie, MI by SUnday afternoon, the cold front will pack a wind punch as it swings eastward over the area. Pressure rises are forecast on the order of 7-9 mb/6 hr, and the cold advection profiles will steepen the lapse rates in the lowest few thousand feet of the atmosphere to allow for good mixing. If the stratocumulus can dissipate, that would increase chances of tagging 40+ mph gusts with regularity in the mid to late afternoon, but that's more of an upper end outcome.

Temperatures will head downward on the westerly winds with high confidence. Wind chills by early Monday morning look to be in the upper single digits to mid teens, which a week ago was nothing, but we will definitely all feel that given current conditions.

MTF

LONG TERM. 240 PM CST

Monday through Saturday .

While temperatures will be slightly below normal on Monday, March certainly won't be coming in like a lion. After the cool start to meteorological spring, the rest of the work week will feature above normal temperatures, warmest Wednesday and Thursday. There are no real weather impact concerns for the upcoming work week into the first weekend of March.

A secondary reinforcing cold front will sweep across the area during the day on Monday, shifting winds to breezy (gusts up to 25 mph) out of the northwest. The 850 mb thermal trough will aim for points northeast of our area, but still glancing blow of ~-10 Celsius into northeastern Illinois. The 500 mb short-wave associated with the secondary front will have an area of light snow with it across central and possibly southern Wisconsin, so could be a bit more cloud cover to the north through early afternoon. Still, should average out mostly sunny to partly cloudy. With the later timing of stronger cold advection than previous model runs, a good amount of strong March sun, and very little if any remaining snow cover for most, expecting highs to range from the mid to upper 30s north to the low to locally mid 40s south of I-80, which is again a bit below normal ~40F high north of I-80 for March 1st.

Strong surface high pressure around 1030 mb will move overhead Monday night, setting the stage for good radiational cooling and possibly one of the last cold nights until later next fall. Forecast lows are in the teens outside Chicago and around 20/low 20s in the city, with typically favored cold spots expected to bottom out in the 11-14F range. The high pressure will shift east on Tuesday, so we should see highs moderate to around normal or slightly above it in the afternoon after the chilly start. Mild air mass overhead and plenty of sunshine will then support highs in the lower to mid 50s Wednesday and mid to upper 50s Thursday (with a key exception described below).

Very weak gradient on Thursday should allow an early season lake breeze to form and keep temps lakeside in the 40s, or cool temps into 40s after wind shift. A backdoor cold front emanating from strong high pressure over the northern Lakes will overtake the lake induced onshore winds Thursday night into Friday. This will be followed by decent cold advection. Thus expect temps 5-10 degrees colder for highs on Friday and seasonably cool temps to start next weekend. With onshore winds, locations near the lake may not get out of the upper 30s Friday and Saturday. Beyond day 7, there is strong agreement in the ensembles in a transition to a western troughing and eastern ridging mid and upper level pattern into the 2nd week of March. This points towards above to well above normal temps for several days, aside from any lake cooling.

Castro

AVIATION. For the 18Z TAFs .

The concerns for the Chicago area airports are:

- Southwest winds becoming southeast early this evening

- Increasing confidence in IFR ceilings developing overnight and persisting through Sunday morning; including potential for high impact LIFR ceilings and visibility

- Drizzle and showers late tonight into early Sunday morning

- Winds becoming strong westerly Sunday afternoon, a few gusts reaching 35 kt possible

Light southwest winds will increase some early this afternoon. With the sun, warmth, and increasing moisture, snow melt will be more aggressive and continue into this evening. This will set the stage overnight for IFR and possible LIFR conditions, especially as a weather system draws even more moisture northward. Stratus will expand north over the area early overnight, and the moisture depth looks sufficient for at least patchy drizzle. Also scattered to numerous showers should be seen in the region, with the highest coverage favored southeast of Chicago (possibly well southeast).

Confidence is high in ceiling under 700 ft, and is increasing in ceilings of 500 ft or lower and that these could linger through much of Sunday morning. As for visibility, at least a light fog is expected but it's concerning given what happened this morning and this even more favorable warm advection/snow melt regime. Visibility under 1SM could certainly unfold. It may depend on how widespread any rain showers are, as showers would likely disrupt visibilities that low.

Late Sunday morning into early afternoon, southwesterly flow will increase as low pressure deepens significantly over the northern Great Lakes. This will result in some lifting/scouring of ceilings and visibility between 16Z-20Z, but how quickly is much too uncertain at this distance. The system cold front will pass turning winds westerly and quite gusty, with high confidence in at least occasional 30+ kt gusts between 20Z-23Z.

MTF

LOT WATCHES/WARNINGS/ADVISORIES. IL . None. IN . None. LM . Small Craft Advisory . LMZ740-LMZ741-LMZ742 . noon Sunday to midnight Monday.

Small Craft Advisory . LMZ743-LMZ744-LMZ745 . noon Sunday to 3 AM Monday.



Visit us at weather.gov/chicago

Follow us on Facebook, Twitter, and YouTube at: www.facebook.com/NWSChicago www.twitter.com/NWSChicago www.youtube.com/NWSChicago


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
FSTI2 4 mi120 min 47°F
OKSI2 9 mi120 min ESE 1.9 G 2.9 51°F
CHII2 - Chicago, IL 10 mi40 min SSE 15 G 17 46°F 38°F
CNII2 13 mi45 min S 8.9 G 9.9 51°F 33°F
CMTI2 - 9087044 - Calumet, IL 22 mi60 min S 6 G 8.9 1017.5 hPa (+0.3)
WHRI2 - Waukegan Harbor, IL 24 mi120 min SE 7 G 11 39°F
BHRI3 - Burns Harbor, IN 39 mi80 min S 4.1 G 6 48°F 1019 hPa
KNSW3 - Kenosha, WI 39 mi60 min S 8.9 G 12 38°F 1017.6 hPa (+0.3)
MCYI3 - Michigan City, IN 46 mi40 min SSE 8.9 G 11 44°F 37°F

Wind History for Calumet Harbor, IL
(wind in knots)    EDIT      (on/off)   Help
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
24hr
SE8
G12
SE9
G14
SE5
G10
SE9
G14
SE6
G10
SE9
G12
S4
G7
S4
SW6
S4
SW5
SW5
SW4
SW5
S8
S7
G10
SW5
G9
SW6
SW7
G11
SW7
G13
S8
S10
S9
G12
S6
G9
1 day
ago
E4
SW5
W4
G8
SW5
SW3
SW4
S4
S2
S2
SW4
S4
S4
S4
S1
SE4
SE7
G11
SE5
G9
SE7
G10
SE12
G16
SE10
G14
SE9
G15
SE8
G11
SE11
G17
SE9
G12
2 days
ago
NW8
G12
N11
G15
NW4
NW1
W2
SW3
SW2
W2
W2
SW3
SW3
W3
SW3
SW2
SW4
SW4
SW4
SW5
SW5
G10
W7
G13
NW9
G15
W7
G10
SW7
G10
E5
G8

Airport Reports
    EDIT      (on/off)   Help   Click EDIT to display multiple airports. Follow links for more data.
AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Chicago / Wheeling, Pal-Waukee Airport, IL12 mi68 minS 610.00 miFair53°F33°F47%1018 hPa
Chicago, Chicago-O'Hare International Airport, IL12 mi69 minSSW 610.00 miPartly Cloudy51°F34°F52%1017.6 hPa
Chicago, Chicago Midway Airport, IL17 mi67 minS 810.00 miPartly Cloudy49°F34°F56%1018.4 hPa

Link to 5 minute data for KPWK

Wind History from PWK (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 24hrS9SE8E4SE4SE6SE8S9S4S7SW3SW5SW4CalmS3S3S5SW4SW7W7SW6SW5S64S6
1 day agoSW7W7W5SW3S3S3S3S4S4CalmCalmCalmCalmCalmCalmCalmS9S5S8S9S13S14S11S9
2 days agoN9NW10
G17
NW4CalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmW3W5W8NW8NW10NW11NW7
G18
NW9SW8

Tide / Current Tables for
   EDIT   Weekend mode (on/off)   (on/off)   Help
Tide / Current Tables for
   EDIT      (on/off)   Help
Weather Map
       (on/off)   Help Weather Map
wmap_A
GEOS Local Image of    EDIT
NOTE: This section has been updated as of 1/26/2021. If the image you are expecting is not showing, please let me know. You may use the EDIT function to update your location.
Link to Loop

Other links: GEOS-West     Contential US     Full GOES-East
Ground Weather Radar Station




Cookie Policy:
This website uses cookies to save your settings. No personal information is saved. I do not collect statistics on your visit. You can disable cookies in your browser if you like but it is not recommended for this site. I do not sell cookies. Go to a bakery for that. In fact I do not sell anything. To disable cookies from L-36.com, please refer to the Help button in your browser.
Privacy Policy:
I do not sell or share any user data or anything else for that matter. The only personal information I save is in the site log which has a line for each page view which includes the IP address your browser sends in the header as well as which page you requested. I use this to block hackers and other bad actors. I do not use this raw data to create profiles on users. I periodically delete the log files. Google supplies the ads on this site. Because I do not track who you are, I cannot customize how these ads are served. They may be personalized to improve the ad experience. If you do not want personalized ads, please adjust the settings on the Google site HERE. NOTE: The best I can determine, this site is not subject to CCPA but I am doing my best to comply anyway.
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 numerous 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.