Marine Forecasts

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7 Day Forecast for Marine Location Near Lincolnwood, IL

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Area Discussion for - Chicago, IL

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FXUS63 KLOT 030457 AFDLOT

Area Forecast Discussion National Weather Service Chicago/Romeoville, IL 1157 PM CDT Thu Apr 2 2020

SHORT TERM. 219 PM CDT

Through Friday .

Temperatures are warming nicely (to around 60) across inland areas this afternoon under mostly sunny skies. While skies have been mostly sunny, expect higher level cloudiness to increase over the area later this afternoon in advance of our next weather system. Skies will thus become mostly cloudy across the area for tonight. A weak mid-level disturbance, noted in the GOES 16 water vapor imagery over northern MO and southern IA, is expected to shift across our area tonight. As it does so, we could have a few light showers develop over northern IL tonight. Overall, this will not be a big deal, but we do have some low end chances for rain overnight, primarily across northern IL.

On Friday we will be awaiting the arrival of a cold front approaching western IL late in the day. Since this front will not move into our western areas until Friday evening, it appears most, if not all of the day Friday will be precipitation free for the area. Instead, it appears the primary threat for rain should hold off until Friday evening. While it is looking dry, there is likely to be more cloud cover around. In spite of this, warmer conditions are expected thanks to a thermal ridge featuring 925 mb temperatures around 11C advecting northward ahead of the approaching front. This should yield afternoon high temperatures into the mid 60s inland from Lake Michigan. Close to the lake, however, onshore winds are likely keep temperatures in the upper 40s to low 50s.

KJB

LONG TERM. 310 PM CDT

Friday Night through Thursday .

A slow moving cold frontal passage will bring rain showers to the area Friday night into Saturday, followed by quiet conditions through Sunday night. Next work week will be mild and unsettled with thunderstorm chances in the first part of the week and then turn cooler later in the week.

Friday Night through Sunday Night:

A narrow plume of anomalous PWATs (about 150-200% of normal) for the time of year of a bit upwards of 1" will be drawn northward with the approach of slow moving cold front from the northwest. A weak frontal wave may initially slow the eastward progress of the front and associated showers. Lower and mid-level convergence and transient frontogenesis along with very modest height falls will drive primarily anafrontal (post-frontal) rain showers. Confidence is high in rain occurrence for the Friday night period, so indicate categorical PoPs gradually translating east-southeastward. Can't completely rule out some embedded thunder, however it appears sub-slight chance mention as instability will be very meager. Relatively steep lapse rates will maximize above 600 mb, so lifting would have to be high up in the column. With probabilistic thunder products sub-mentionable over the area and better chances off to the west/southwest of west/southwest CWA area, opted to remove thunder mention.

There may be some embedded moderate rainfall rates depending on if f-gen is more than transient, with upside potential in rainfall amounts in a narrow swath given presence of well above normal column moisture. NAM hints at this sort of potential, though guidance is mixed. For now, WPC QPF totals around 1/4" appear reasonable and will be able to add detail as needed with subsequent updates. Expansive high pressure ridge building in from the northwest will give the front and associated rain/showers an extra push during the day on Saturday, so there should be fairly quick drying from northwest to southeast across Illinois counties. As such, added some temporal resolution to the PoP grids. Saturday will be 10-15 degrees cooler than Friday away from the lakeshore in the lower to mid 50s and only mid-upper 40s lakeside as winds turn north to northeast behind the front. It appears that Saturday evening through Sunday night will then be dry (minor exception of last showers exiting far southeast early Sunday evening). Sunday will feature partly cloudy skies and moderate back to the mid- upper 50s inland, but stay chilly lakeside in the 40s under continued northeast surface flow.

Castro

Monday through Thursday:

Medium range guidance continues to develop a long wave trough along the west coast early next week, with a broad downstream upper ridge across the eastern CONUS. With quick southwesterly flow aloft, surface low pressure is progged to develop out of the Plains and progress northeast to the western Great Lakes region through mid-week. In the process, a warm front lifts across the region, bringing warmer (potentially 70+ degrees on Tuesday) and more humid air into the region. Shower and thunderstorm potential also increases, with a few periods of unsettled weather likely Monday into early Wednesday.

The pattern is rather messy and thus uncertain as depicted in the guidance and ensembles, with a few to several short-waves traversing the area and large variance on timing. Surface pattern and timing of waves of showers/storms and associated cloud cover will also dictate exactly how mild it gets and possible lakeside cooling. It will take some time to sort out specific details, so confidence is on the low side. Depending on the timing and overall evolution, there may be overlap of stronger flow aloft with sufficient moisture and instability to bring a stronger thunderstorm risk somewhere over the region. It appears that initial cold front passage will occur Tuesday night into Wednesday, possibly followed by a reinforcing shot of cooler air to close out the period. Some guidance indicates a rather stout cold shot for this time of year.

Ratzer/Castro

AVIATION. For the 06Z TAFs . 1157 PM CDT

Light and variable winds with VFR overcast skies will prevail through the overnight hours. A passing shower or two is possible at all but GYY with no obstruction to ceiling or visibility expected. After sunrise, winds will become southeasterly with a reinforcement at MDW/ORD by mid-afternoon with a weak lake-breeze. VFR ceilings may scatter out by mid-afternoon. After sunset tonight, a cold front will sweep through northern Illinois first at RFD/DPA and then at ORD/MDW/GYY. A band of showers is possible along the front, though more impactful will be a downward trend in cigs to low-end MVFR toward the end of the TAF period with pockets of IFR possible. For now, will offer OVC015 with lower cigs possible in later TAF packages. Winds will become northeasterly in the wake of the front, as well. Thunder chances appear low through the entire TAF period.

Borchardt

LOT WATCHES/WARNINGS/ADVISORIES. IL . None. IN . None. LM . None.

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Weather Reporting Stations

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Stations	Dist	Age	Wind	Air Temp	Water Temp	Waves	Pressure	DewPt
OKSI2	3 mi	132 min	ESE 4.1 G 7	46°F
CHII2 - Chicago, IL	4 mi	42 min	S 2.9 G 4.1	41°F				38°F
CNII2	7 mi	27 min	Calm G 1	42°F				34°F
CMTI2 - 9087044 - Calumet, IL	16 mi	54 min	NNE 2.9 G 4.1	41°F			1019 hPa	38°F
MCYI3 - Michigan City, IN	41 mi	42 min	E 2.9 G 4.1	46°F				30°F
KNSW3 - Kenosha, WI	45 mi	72 min	Calm G 1	40°F			1019.6 hPa (-0.0)

Wind History for Calumet Harbor, IL

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12 AM

1 AM

2 AM

3 AM

4 AM

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Last 24hr

E3

E2

SE1

NE3

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E2

E1

E1

SE1

NE3

NE6

NE6

NE7

NE6 G10

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NE6

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NE3

1 day ago

NW8 G14

NW9 G12

NW10 G16

NW9 G15

NW8 G13

NW9 G13

NW8 G11

NW7 G10

N10 G13

NW9 G13

NW10 G13

NW8 G12

NW9 G12

N9 G12

N12 G15

N9 G13

N6 G9

NE5

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NE3

2 days ago

N10 G14

N10 G16

N9 G13

N11 G14

N8 G11

N7 G11

N8 G11

N10

N11 G15

N10 G13

N11 G15

N11 G14

N11 G15

NW11 G18

N13 G18

N12 G16

N11 G15

N11 G14

N10 G15

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Airport Reports

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Airport	Dist	Age	Wind kt	Visibility	Sky/Weather	Temp	DewPt	Humidity	Pressure
Chicago, Chicago Midway Airport, IL	13 mi	19 min	E 4	10.00 mi	Overcast	47°F	30°F	54%	1019.8 hPa
Chicago, Chicago-O'Hare International Airport, IL	14 mi	21 min	N 0	10.00 mi	Overcast	48°F	32°F	54%	1019.3 hPa
Chicago / Wheeling, Pal-Waukee Airport, IL	18 mi	20 min	N 0	10.00 mi	A Few Clouds	46°F	33°F	61%	1019.9 hPa

Link to 5 minute data for KMDW

Wind History from MDW (wind in knots)

1 AM

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Last 24hr

E3

Calm

Calm

Calm

S3

Calm

Calm

Calm

Calm

SE6

E6

SE4

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NE8 G16

E9

E9

--

E8

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--

E7

E4

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E4

1 day ago

N9

N8

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N6

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N5

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N4

NE3

N5

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NE11

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NE4

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E5

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SE3

2 days ago

NE12

NE9

N10

N9 G18

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N13

NE8

N7

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N10

N10

N10

N10

NE11

NE11

N13

N11

N11

N10

N12

N10

N9

N12

N7

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Tide / Current Tables for

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Tide / Current Tables for

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Weather Map

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GEOS 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.
Link to Loop

Other links: Northern Pacific     Contential US     Full GOES-East

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Wind Forecast for Chicago, IL (1,6,7,8)

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Ground Weather Radar Station Chicago, IL

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