Marine Forecasts

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7 Day Forecast for Marine Location Near Hammond, IN

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Area Discussion for - Chicago, IL

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Fxus63 klot 251053 afdlot area forecast discussion national weather service chicago romeoville, il 553 am cdt Sun aug 25 2019 Short term 158 am cdt through tonight... a still mainly quiet weather pattern continues into today, though a cloudier one and a sign of gradually increasing ascent and moisture. With this some spotty sprinkles are possible this afternoon into early evening before scattered showers are likely late this evening into the overnight. Upper and surface ridging are slowly moving east from the region this morning. The upper ridging has been stout with 500 mb heights of 589 dam last evening over the area. This has served as blocking to the west, however a stronger jet of 110+ kt surging across the northwest u.S. This morning will being to impinge into and weaken this ridge as it shifts east. Clouds will gradually thicken today in response and a subtle disturbance near st. Louis this morning will slowly meander north-northeast toward the area. Last evening's soundings showed substantial dry air above 850 mb which will take time to saturate, and thus believe through early evening it will be difficult to get more than spotty sprinkles. The clouds and continued easterly winds will prevent temperatures from moderating much from yesterday, with a 2-3 degree increase expected. On the note of easterly winds, these once again will be providing onshore flow into northeast illinois and lake michigan beach conditions will be close to a high rip current risk. At this time expecting more of a moderate risk, but for locations north of chicago it will be close with 3-4 ft waves forecast. The upper pattern begins to show a little more cohesiveness tonight with a potential vorticity perturbation developing over or just west of the region and low-level flow turning more southerly steering in higher precipitable water air. Moistening on the isentropic surfaces with the stronger lift still looks marginal, likely resulting in only scattered showers. The eastern half of the forecast area may be a little more favored with the aforementioned wave over st. Louis this morning slowly lifting north-northeast serving as one focus, with the greater synoptic forcing still west. Elevated lapse rates are weak because of this so the thunder threat looks limited though cannot rule out an isolated non-severe storm or two overnight south and west. Mtf Long term 434 am cdt Monday through Saturday... the long term forecast period will start out active with periods of showers and thunderstorms lingering into Tuesday morning. Much of the remainder of the period should be dry, though there may be another chance for precipitation for Friday and into next weekend. Showers and thunderstorms should be ongoing across eastern il and northern in Monday morning in response to a southern stream shortwave lifting from the lower missouri valley and across central in and northern in. Showers and thunderstorms will be mostly south of i-80 in il but all of nwrn in will like see some activity. However, some scattered showers and thunderstorms cannot be ruled out for NRN il. As this initial wave continues to lift newd, weak shortwave ridging and mid-level drying may bring a lull in the pcpn for Monday afternoon, though some sct showers may be possible. A strong northern stream shortwave will drop into the well upper midwest by early Monday evening with an associated cold front moving

from ERN ia into nwrn il. In advance of the system, deep layer moisture will continue to increase, with pwats just under 2 inches pooling ahead of the sfc cold front. Steep mid-level lapse rates, a 40 kt low-level jet combined with the high moisture level and moderate instability will bring both chances for severe thunderstorms and localized flooding. Strong winds will be the primary severe threat. Flooding potential should be limited due to the relatively dry conditions over the past few weeks, giving area rivers ample storage capacity. However, some of the latest guidance is suggesting that the progression of the cold front across the region may be slower than previously anticipated, so any heavy rain producing storms may have a longer residence time over a given area, increasing the flooding potential. The cold front is expected to push east of the CWA by late Tuesday morning so there could be some lingering showers over nwrn in through the morning. The entire cwa should be rain-free by the afternoon. Dry and pleasant conditions should return to the area for midweek as a surface high builds across the middle mississippi valley through the ohio valley. High temperatures will be around 80 f for Monday and Tuesday. As the upper level pattern trends toward more high amplitude long wavelength, with upper riding over the west coast and broad upper troughing over the ERN 2 3 conus, the resultant nwly flow general troughiness aloft will keep temperatures below seasonal normals, with highs in the middle to upper 70s for much of the remainder of the period, though highs could reach 80 f on Thursday as weak shortwave riding moves across the area in between a series of weak shortwaves rotating around the base of the main upper low over scntrl sern canada. The next chance for precipitation may come by the end of the week into next weekend with some of the long range guidance suggesting the next frontal passage. However, this guidance is also trending the upper level flow pattern to move zonal across much of the nrn CONUS by the end of the week, so timing of any shortwaves and associated features are low confidence at this time range. Aviation For the 12z tafs... concerns for the chicago area tafs through Monday morning are: - easterly winds increasing to just above 10 kt late this morning with occasional gusts - chance for showers late tonight into early Monday morning, with a small chance for isolated thunderstorms - MVFR clouds likely Monday morning with a chance for ifr high pressure across the eastern great lakes will continue to gradually move away from the area today resulting in increasing easterly winds. Otherwise for today and early this evening, dry air aloft is likely to prevent showers from reaching the tafs during that time though patchyVFR sprinkles may occur. For late this evening into Monday morning, both lift and saturation will gradually improve and scattered showers are favored. Parameters for thunderstorms in the local area look limited through Monday morning, but cannot rule it out with isolated coverage if any can develop. The moistening conditions look supportive of MVFR ceilings and likely some ifr to expand northeast from western illinois during early Monday morning. How far this progresses into the area, especially ifr, is a detail that will have to be analyzed further in time. But the potential for ifr is there, especially in the few hours immediately after any early a.M. Showers. Mtf Lot watches warnings advisories Il... None. In... None. Lm... None. Visit us at http: weather.Gov chicago (all lowercase) follow us on facebook... Twitter... And youtube at:

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Weather Reporting Stations

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Stations	Dist	Age	Wind	Air Temp	Water Temp	Waves	Pressure	DewPt
CMTI2 - 9087044 - Calumet, IL	8 mi	48 min	ESE 6 G 8.9	69°F			1019.8 hPa	55°F
JAKI2	12 mi	138 min	Calm G 2.9	70°F
CNII2	17 mi	33 min	ESE 9.9 G 11	72°F				57°F
BHRI3 - Burns Harbor, IN	18 mi	38 min	ESE 6 G 8	70°F			1021.3 hPa
45177	20 mi	138 min			73°F	1 ft
CHII2 - Chicago, IL	21 mi	28 min	ESE 16 G 18	69°F				60°F
OKSI2	21 mi	138 min	SSE 4.1 G 7	71°F
FSTI2	26 mi	138 min	SE 16	67°F
45170	29 mi	28 min	ESE 9.7 G 9.7	66°F	65°F	1 ft		57°F
MCYI3 - Michigan City, IN	32 mi	28 min	E 6 G 8.9	68°F				54°F
45174	37 mi	28 min	ESE 12 G 16		72°F	3 ft	1019.4 hPa

Wind History for Calumet Harbor, IL

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E10 G14

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Airport Reports

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Airport	Dist	Age	Wind kt	Visibility	Sky/Weather	Temp	DewPt	Humidity	Pressure
Gary Regional Airport, IN	4 mi	33 min	SE 8	10.00 mi	Mostly Cloudy	70°F	51°F	53%	1020.7 hPa
Lansing Municipal Airport, IL	7 mi	43 min	SE 6	10.00 mi	Fair	68°F	55°F	63%	1021 hPa
Chicago, Chicago Midway Airport, IL	18 mi	85 min	SE 9	10.00 mi	Mostly Cloudy	68°F	54°F	61%	1020.1 hPa

Link to 5 minute data for KGYY

Wind History from GYY (wind in knots)

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Tide / Current Tables for

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Tide / Current Tables for

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Weather Map and Satellite Images

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GOES 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.
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Wind Forecast for Chicago, IL (11,2,3,4)

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Ground Weather Radar Station Chicago, IL

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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.