Wednesday, April26, 2017 L-36.com


Marine Weather and Tides
Winthrop Harbor, IL

Version 3.4
What's New / NOTES
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.
3/12/2015 - Added section for Gulf current for users in the GMZ marine zones.
This was requested by a user. If you have requests, please let me know.

Sunrise 5:50AMSunset 7:47PM Wednesday April 26, 2017 6:51 AM CDT (11:51 UTC) Moonrise 6:20AMMoonset 8:07PM Illumination 0% Phase: New Moon; Moon at 0 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
LMZ646 Wind Point Wi To Winthrop Harbor Il- 326 Am Cdt Wed Apr 26 2017
.small craft advisory in effect through this evening...
Today..South wind 10 to 15 knots with gusts to around 20 knots. Chance of showers until late afternoon. Slight chance of Thunderstorms in the late morning and afternoon. Rain showers likely late in the afternoon. Waves 3 to 5 feet.
Tonight..South wind 10 to 15 knots becoming southwest 5 to 10 knots after midnight, then rising to 10 to 15 knots early in the morning. Slight chance of Thunderstorms through around midnight. Rain showers through the night. Waves 2 to 4 feet subsiding to 1 to 2 feet after midnight.
Thursday..West wind 10 to 20 knots becoming 15 to 20 knots in the late morning and afternoon. Chance of rain in the morning. Waves 1 to 2 feet.
Thursday night..Southwest wind 10 to 15 knots with gusts to around 20 knots becoming west 5 to 10 knots after midnight. Mostly cloudy. Waves around 1 foot.
LMZ646 Expires:201704261615;;282736 FZUS53 KMKX 260826 NSHMKX NEARSHORE MARINE FORECAST NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI 326 AM CDT WED APR 26 2017 FOR WATERS WITHIN FIVE NAUTICAL MILES OF SHORE ON LAKE MICHIGAN LMZ646-261615-

7 Day Forecast for Marine Location Near Winthrop Harbor village, IL
   Hourly   EDIT   Help
location: 42.47, -87.82     debug


Area Discussion for - Chicago, IL
      (on/off)   Help   NOTE: mouseover dotted underlined text for definition
Fxus63 klot 261143
afdlot
area forecast discussion
national weather service chicago/romeoville, il
643 am cdt Wed apr 26 2017

Short term
245 am cdt
through Thursday...

a bit more active day is expected today across the region with a
series of upper level lows spinning across the plains with heavy
rain a considerable concern, along with some risk for severe
weather especially later today/this evening.

The presence of altocumulus castellanus clouds Tuesday afternoon
is well understood looking at the dvn/ilx 0z soundings. While
these are still very dry downstairs they depict the presence of
the elevated mixed layer with 700-500 mb lapse rates very steep,
8-9 deg/km but very high based above 700 mb. Instability therefore
was pretty small, but weak shortwave energy was able to tap into
this to trigger a few storms across northwest indiana Tuesday
evening. The sgf sounding, indicative of the airmass to some of
the area headed our direction, depicts 1000 j/kg of CAPE and near
50 kt of deep layer shear. This coupled with -20c height of about
21k ft suggests that there are several thunderstorms concerns
later today.

Water vapor satellite depicts a fairly strong wave across
oklahoma with some weaker waves ahead of it, and these will
continue northeast through north central illinois this morning
where the best t-storm threat would be. Current showers to our
west are in a minimum of mid level lapse rates and thus no
thunder. Rap forecasts of instability creep up as this stronger
wave well southwest shifts in the coming hours, but does not get
too high with this wave. The airmass is still on the drier side
with this lead wave, so expect a decent cut off to the eastern
extent of thunderstorms this morning, but expect there could
certainly be some high based showers farther east as well. There
could be some hail with the stronger storms, but the main storms
should be through before instability increases to the levels of
severe concerns. Expect some weakening as the low level jet
wanes through the morning with a downtick likely.

More significant height falls will occur this afternoon as the
upper lows spread eastward, the upper level jet will also undergo
some strengthening indicating a system getting stronger, and
providing good forcing for ascent ahead of an advancing cold
front. This forcing will come atop and increasingly unstable
airmass mainly due to advection, but it will limited farther
north and especially west of i-55 due likely significant cloud
cover which could keep convection coverage less initially. Plus,
there are some weaker lapse rates aloft that will creep in from
the west across illinois this afternoon and some stability with
the approaching cold front which will mitigate the severe threat
for areas northwest, but these do look to recover some later. Still will
need to watch any leading cells that remain discrete as they could
pose a localized severe threat.

The moisture transport kicks into a bit of higher gear tonight as
instability is waning, though instability will get nudged up some
at least before late evening, especially along the i-55 and
eastward corridor. This is the period where any line/bowing
segments lifting up from likely more active convection to the
south pose a more significant severe concern, as when this occurs
the low level shear really increases. The low level shear/helicity
values get fairly large as well. Instability will weaken later
this evening as we trend to a heavy rain threat as soundings
depict a very deep and saturated profile with pw values from
1.3-1.5" for several hours but little much less instability. There
will also be a very strong frontogenesis with the encroaching
cold front that it could really dump rain for a few hours. This
may end up for many areas being a more significant concern than
the severe threat. Overnight the upper low will still shift
through with some lingering fgen, so in spite of the cold front
stabilizing things overnight, modest rains could still fall late
into early Thursday in a band farther west, with some showers
underneath the low itself that could still have a little kick.

Fortunately the dynamic cooling does not look like enough to get
over to a snow profile (had to find a way to sneak snow into this
afd) as hinted at by a nambufr sounding near rfd early Thursday.

The moisture axis and low will shift north in the afternoon ending
precip as much colder and drier air filters back in from the
west/northwest.

Kmd

Long term
245 am cdt
Thursday through Monday...

the concern for the weekend will be heavy rainfall and periods of
thunderstorms. The lowest GEFS ensemble member from 0z suite has
2.25 inches of QPF for ord with Wednesdays and the weekend
precipitation, so this certainly indicates flooding concerns
exist, including a re- aggravation of rivers that have just
recently subsided.

The northern stream upper low will linger across the northern
great lakes Friday with a massive longwave trough enveloping much
of the country, but there is a small ridge axis that will setup
across the upper midwest ahead of developing low pressure out
west. Southwest flow ahead of the developing low will send waves
of precipitation through at times until this upper low really
gains some strength and eventually shifts northeastward through
our region. The first wave appears to be on Friday with a leading
warm advective wing. Precipitation could be initially light, but
nam/gfs project a strong and strengthening upper jet with a
northward moving warm front to lead to some better rains, though
the locations are a bit hairy to project and could split us a bit
north and south. At this point thunder looks like a minimal
concern.

The northward moving front gets shoved south by the high pressure
area mentioned earlier. This will keep the area locked in a
cooler northeast wind pattern and could keep precipitation on the
lighter side on Saturday. Confidence is not high though as the ec
is still somewhat wet Saturday afternoon, but is possible the high
to our north keeps the better activity south.

The big issues appear to come Saturday night into Sunday. This
period holds the highest concern for very wet conditions and
the aforementioned flood concerns with significant warm advection
induced precip beginning Saturday night, which could the wettest
period, but alot to still iron out here. It will also be windy at
times, with thunderstorms re- entering the picture as well. More
to come on this once we get through Wednesday's active weather.

Kmd

Aviation
For the 12z tafs...

643 am... Forecast concerns include thunderstorm potential this
morning and again this afternoon/evening... Wind directions this
evening... And CIGS this evening through Thursday morning.

Current area of convection over west central il will continue
moving northeast this morning and short term guidance has slowly
been lifting this activity further northeast toward the chicago
area terminals. There may still be a weakening trend but thunder
potential is high enough to include tempo mention as this area of
precipitation moves across northern il. Isolated showers or
perhaps a thunderstorm may continue late morning into early this
afternoon... But overall this appears to be a quiet period with
the best chance of any activity across northwest il. Additional
thunderstorms are expected to develop late this afternoon and
continue into this evening. Still some uncertainty regarding
coverage/location with the best chances along/east of a
pnt/jot/mdw line... But trends will need to be monitored into this
afternoon. Rain will continue this evening... Possibly heavy at
times with showers continuing overnight. There may still be some
embedded thunder this evening... But confidence is low.

Southerly winds will turn a bit more south/southwesterly later
this morning. Confidence on speeds and gusts is only medium with
low level mixing possibly not as deep... Which would result in
lower speeds/gusts. As low pressure approaches the region this
evening... Gusts should diminish and wind directions become quite
uncertain. Current track of the low would allow winds to shift
southeasterly this evening... And then turn southwesterly once the
low lifts north of the area. Forecast soundings suggest a wind
shift to the northwest this evening with a low passage just east
of the chicago terminals. Maintained southeast winds with this
forecast but changes to wind directions... Perhaps significant
changes... Are possible with later forecasts.

GenerallyVFR CIGS through late afternoon with perhaps some patchy
MVFR with precip this morning. CIGS will then lower through MVFR
this evening and likely to ifr overnight... But confidence on
specific heights as well as timing is low. Slow improvement to or
through low MVFR is expected Thursday morning. Cms

Marine
220 am... One area of low pressure over eastern ia will lift
northeast into wi this morning as it slowly weakens. A trailing
cold front extends to a second area of low pressure over the
southern plains. This low will move northeast over lake michigan
tonight. Southerly winds today will shift more southeasterly this
evening and then west/southwest Thursday as the low continues
moving into ontario. Small changes to the track of the low will
have large impacts on wind directions. Thus... Changes to wind
directions are possible with later forecasts.

A weak ridge of high pressure will move across the lakes region
Friday and remain nearly stationary across the northern lakes
Saturday... As high pressure then builds across ontario. Low
pressure will develop over the southern plains and eventually
lift northeast to the western great lakes Sunday night. The
gradient between the high to the north and this approaching low
will slowly tighten with northeasterly 30kts expected and the
potential for some low end gales... Especially over northern lake
michigan by Sunday evening. Cms

Lot watches/warnings/advisories
Il... None.

In... None.

Lm... Small craft advisory... Nearshore waters until 11 pm
Wednesday.

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
KNSW3 - Kenosha, WI 8 mi51 min S 9.9 G 14 51°F 998.3 hPa (-1.0)
WHRI2 - Waukegan Harbor, IL 8 mi71 min SSW 8.9 G 12 53°F
FSTI2 35 mi111 min S 9.9 62°F
OKSI2 40 mi111 min E 4.1 68°F
MLWW3 - Milwaukee, WI 40 mi41 min SSE 12 G 13 50°F
CHII2 - Chicago, IL 40 mi81 min SSE 13 G 13 61°F 55°F
45007 - S MICHIGAN 43NM East Southeast of Milwaukee, WI 44 mi61 min ESE 12 G 14 47°F 41°F1 ft999.2 hPa (-0.9)46°F
CNII2 44 mi36 min S 9.9 G 15 65°F
JAKI2 49 mi111 min S 8 67°F

Wind History for Calumet Harbor, IL
(wind in knots)    EDIT      (on/off)   Help
7
AM
8
AM
9
AM
10
AM
11
AM
12
PM
1
PM
2
PM
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
Last
24hr
SE9
G15
SE10
G15
S9
G14
S11
S9
SE10
G14
S11
G16
S10
G13
SE10
G16
SE9
G14
SE11
G15
SE11
G16
SE10
G15
SE9
G15
SE7
G11
SE7
G11
SE5
SE7
SE7
G10
SE7
G11
SE8
G12
SE10
G15
S8
G13
SE9
G12
1 day
ago
N3
N5
NE3
G6
N6
N6
NE6
G9
N6
N8
N7
NE9
N7
N6
N6
NE4
E5
E7
G10
E6
E7
G10
SE8
G12
SE10
G16
SE9
G12
SE9
G13
SE9
G13
SE8
G14
2 days
ago
SW3
S2
E3
NE5
NE5
NE7
NE6
E5
E6
E7
E7
E6
E4
E4
NE2
N6
G9
N8
N8
N7
N9
G12
N5
N4
N6
N2
G5

Airport Reports
    EDIT      (on/off)   Help   Click EDIT to display multiple airports
AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Chicago/Waukegan Regional Airport, IL4 mi56 minSSE 78.00 miFair56°F52°F87%997.1 hPa
Kenosha, Kenosha Regional Airport, WI10 mi58 minSE 710.00 miFair58°F52°F81%997.3 hPa
Racine, Batten International Airport, WI20 mi58 minS 9 G 1710.00 miFair54°F48°F83%998.1 hPa

Wind History from UGN (wind in knots)
7
AM
8
AM
9
AM
10
AM
11
AM
12
PM
1
PM
2
PM
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
Last 24hrSE8SE11SE6SE6SE9SE13SE15SE10SE11
G17
SE12SE9SE7SE9SE7E4SE6SE7SE9SE9SE6SE6SE6SE6SE7
1 day agoCalmE4E5E6E5SE9SE9SE11--E8E6E7E5E4E4CalmSE5SE7SE10SE8SE8SE8SE7SE9
2 days agoSW3W34SW6NW7N7N8SE10SE8SE8NE11NE10NE7NE8NE4NE5N4N3CalmCalmCalmN3CalmCalm

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 GreatLakes    EDIT
Geos

Wind Forecast for Chicago, IL (7,2,3,4)
      (on/off)   Help

Ground Weather Radar Station Milwaukee, WI
   (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.