Marine Weather and Tides
6/25/2017 - NOAA is having a major issue that impact the 7 day forecast load times. Many users are reporting problems. The issue has been reported.
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 6:22AM||Sunset 9:20PM||Thursday July 20, 2017 6:29 PM EDT (22:29 UTC)||Moonrise 2:42AM||Moonset 5:41PM||Illumination 8%|
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|LMZ872 Lake Michigan From Michigan City In To St. Joseph Mi 5 Nm Offshore To Mid Lake- Lake Michigan From Sheboygan To Port Washington Wi 5 Nm Offshore To Mid Lake- Lake Michigan From Port Washington To North Point Light Wi 5 Nm Offshore To Mid Lake- Lake Michigan From North Point Light To Wind Point Wi 5 Nm Offshore To Mid Lake- Lake Michigan From Wind Point Wi To Winthrop Harbor Il 5 Nm Offshore To Mid Lake- Lake Michigan From Winthrop Harbor To Wilmette Harbor Il 5 Nm Offshore To Mid Lake- Lake Michigan From Wilmette Harbor Il To Michigan City In 5 Nm Offshore To Mid Lake- Lake Michigan From Whitehall To Pentwater Mi 5 Nm Offshore To Mid Lake- Lake Michigan From Grand Haven To Whitehall Mi 5 Nm Offshore To Mid Lake- Lake Michigan From Holland To Grand Haven Mi 5 Nm Offshore To Mid Lake- Lake Michigan From South Haven To Holland Mi 5 Nm Offshore To Mid Lake- Lake Michigan From St. Joseph To South Haven Mi 5 Nm Offshore To Mid Lake- 249 Pm Cdt Thu Jul 20 2017 Sheboygan Wi To Pentwater Mi South... |
Tonight..Variable winds 10 to 15 kt diminishing to 5 to 10 kt. Waves 1 to 3 ft.
Friday..Southeast winds 5 to 10 kt increasing to 10 to 15 kt in the afternoon. Slight chance of showers and Thunderstorms in the morning...then chance of showers and Thunderstorms in the afternoon. Waves 1 ft or less.
Friday night..Southeast winds 10 to 20 kt increasing to 15 to 25 kt. Showers and Thunderstorms likely in the evening... Then showers and Thunderstorms overnight. Waves 1 to 3 ft.
Saturday..South winds 10 to 20 kt becoming southwest. Chance of showers and Thunderstorms. Waves 1 to 3 ft.
Saturday night..Northwest winds 10 to 20 kt. Chance of showers and Thunderstorms in the evening. Waves 1 to 2 ft.
Sunday..West winds 10 to 20 kt. Waves 1 to 3 ft.
Sunday night..North winds 10 to 20 kt increasing to 15 to 25 kt after midnight. Waves 1 to 3 ft building to 3 to 5 ft.
Monday..North winds 15 to 25 kt. Waves 3 to 5 ft.
Tuesday..East winds 10 to 15 kt becoming northeast. Waves 1 to 2 ft.
|LMZ872 Expires:201707210330;;557932 FZUS63 KLOT 201949 GLFLM OPEN LAKE FORECAST for Lake Michigan National Weather Service Chicago/Romeoville IL 249 PM CDT Thu Jul 20 2017 FOR WATERS BEYOND 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 wave, along with the average height of the highest 10% of the waves which will occasionally be encountered. .SYNOPSIS...A trough of low pressure averaging 29.9 inches over the lake will weaken this evening. A weak high of 30.0 inches will move over the lake tonight, and then shift over the eastern Great Lakes Friday evening. Low pressure of 29.6 inches will move over the lake Saturday night, and then move over the eastern Great Lakes Sunday. An expansive 30.2 inch high will then spread over the northern and western Great Lakes Monday night and Tuesday. LMZ080-669-671-673-675-777-779-870-872-874-876-878-210330-|
7 Day Forecast for Marine Location Near Montague, MIHourly EDIT Help
Area Discussion for - Grand Rapids, MI  (on/off)  Help NOTE: mouseover dotted underlined text for definition
|Fxus63 kgrr 201913|
area forecast discussion
national weather service grand rapids mi
315 pm edt Thu jul 20 2017
synopsis short term long term hydro marine
Issued at 315 pm edt Thu jul 20 2017
a weak high pressure ridge will bring fair but continued very warm
and humid weather tonight through Friday morning. Several rounds
of thunderstorms are expected from late Friday through Saturday
night. Some strong to severe storms will be possible with heavy
rainfall and localized flooding possible as well.
Short term (this evening through Saturday night)
issued at 315 pm edt Thu jul 20 2017
main short term fcst concerns continue to involve assessment of
convective svr wx hvy rain potential through Saturday night.
Fair but warm and humid wx will continue tonight through most of
the day Friday with a weak high pressure ridge in place.
Thunderstorms through then should stay just south of our fcst
area in closer proximity to the west to east oriented boundary that
will continue to sink a little further south to near the mi in state
line by this evening. Patchy fog will develop during the early
morning hours Friday as winds go calm with the humid airmass in
It will become hot and quite humid Friday afternoon with high
temps reaching the upper 80's to lower 90's with dew point values
well into the 60's.
We expect a strong LLJ and the stationary front to focus
development of a large MCS over the upper midwest Friday
afternoon and early evening. Mid to upper level thickness tools
for MCS steering propogation and orientation of the stationary front
suggest that the MCS will move southeast along the instability
gradient late Friday through Friday night.
This MCS has potential to bring a corridor of damaging wind gusts
as it potentially evolves into one or several bowing segments given
strong instability and favorable 0-3km shear. Some of the latest
guidance solutions including the 12z ECMWF and 12z NAM continue to
bring the MCS into our fcst area. Other guidance solutions such as
operational GFS trends indicate that the MCS may for the most part
miss us just to the west southwest. All things considered there is
enough potential to continue to carry likely to low categorical pops
for convection late Friday night at this time.
There continues to be potential for very heavy rainfall late
Friday night through Saturday as precipitable water values reach
2-2.25 inches by then along with very strong 1000-850 mb moisture
transport. Dew point values by then should reach the lower to
perhaps middle 70's.
I strongly considered a flood watch headline for portions of our
fcst area for Friday night through Saturday. However ultimately i
felt it was a little too early for this given uncertainty regarding
convective evolution that far out in time. Thx for coord on the no
headline decision iwx.
Although the atmosphere may potentially be worked over somewhat by
showers and storms into early Saturday there is potential for
instability to quickly redevelop later Saturday. Deep layer shear
remains favorable at 35-40 kts.
The SPC day 3 outlook having all of our fcst area in the slgt for
severe wx looks excellent. Convective redevelopment will continue
through Saturday night as the main low pressure wave approaches
from the west and moves through Saturday night.
Long term (Sunday through Thursday)
issued at 315 pm edt Thu jul 20 2017
the main challenge in the long term deals with the potential for any
thunderstorms. The greatest risk looks to be Sunday and again on
Thursday. Models are in reasonable agreement on this scenario.|
A low pressure system is forecasted to track eastward through lower
michigan on Sunday. This system will drag a cold front through the
region. With the atmosphere shown to be unstable... Thunderstorms
will be as possibility. Deep layer shear is forecasted to still be
elevated... Thus organized storms may occur.
The wind turns northeast behind the front. This will push the warm
and humid airmass south of the border. A large area of high
pressure will then move in from canada for Monday into Tuesday as a
mid level ridge sharpens up overhead.
Subsidence will act to keep the cloud cover to a minimum. The
airmass may turn cooler than normal.
Yet another mid level wave heads on direction for the middle part of
the week. Will feature a risk for storms then.
Aviation (for the 18z tafs through 18z Friday afternoon)
issued at 112 pm edt Thu jul 20 2017
overall the risk for storms today is somewhat diminished because
of the convection earlier today. The atmosphere will still be
unstable and a local shower or thunderstorm could develop. Based
on the limited potential... I did not included any storms in the
Fog and stratus could become an issue tonight. Models have been
showing the low level humidity values increasing later tonight
into early Friday. The wind will be relatively weak... Thus any low
conditions that develop may be slow to diminish
Issued at 315 pm edt Thu jul 20 2017
wave heights will continue to gradually subside this afternoon and
tonight as winds become light tonight. Some patchy fog may develop
overnight into Friday morning with a humid airmass in place.
Thunderstorms will pose a hazard to mariners late Friday through
Friday night and again Saturday through Saturday night with
locally higher winds and waves in and near storms.
Issued at 315 pm edt Thu jul 20 2017
the best opportunity for heavy rainfall comes Friday night into
Saturday. A very moist airmass moves in which, combined with
favorable jet structures at 300 mb and 850 mb, will lead to the risk
for efficient rain producing thunderstorms. Since these storms do
not currently exist, it is difficult to say exactly which areas will
get the heaviest rain. Much may hinge on whether any storms that
develop in wisconsin Friday night tend to migrate southward toward
chicago and southern lake michigan (like early Thursday morning) or
expand eastward into western lower michigan. Repeated thunderstorm
movement over the same areas is possible for several hours, which
could lead to some flooding of roads and rapid river rises
especially on small rivers and streams. River responses to the 72
hour ensemble QPF values over our river basins are not raising any
big red flags at this point, as it would take several inches of
rainfall to start flooding main stem rivers. That is uncertain at
Pwat values approaching or exceeding 2.00" is expected for most, if
not all, of the region Friday night and Saturday. With the sfc low
remaining west of the region through Saturday afternoon, the threat
for heavy rainfall continues well into the day should any convection
Grr watches warnings advisories
short term... Laurens
long term... Mjs
Weather Reporting StationsEDIT (on/off)  Help NOTE: Click on distance to see the station location on a map
|Stations||Dist||Age||Wind||Air Temp||Water Temp||Waves||Pressure||DewPt|
|45007 - S MICHIGAN 43NM East Southeast of Milwaukee, WI||32 mi||40 min||ESE 3.9 G 3.9||73°F||72°F||2 ft||1014.5 hPa (+0.0)||71°F|
|45161||36 mi||30 min||SSW 3.9 G 5.8||70°F||65°F||2 ft||1014.6 hPa (-0.3)|
|MKGM4 - Muskegon, MI||37 mi||30 min||WSW 8 G 8||70°F||1014.1 hPa (+0.0)||69°F|
|45029||43 mi||20 min||W 3.9 G 5.8||71°F||68°F||2 ft||1014.1 hPa||67°F|
|45013||44 mi||51 min||SSE 5.8 G 7.8||71°F||69°F||1014.5 hPa|
|MLWW3 - Milwaukee, WI||46 mi||40 min||SE 5.1 G 5.1||70°F|
|PWAW3 - Port Washington, WI||48 mi||50 min||S 8 G 9.9||76°F||1015.2 hPa|
Wind History for Holland, MI(wind in knots) EDIT (on/off)  Help
Airport ReportsEDIT (on/off)  Help Click EDIT to display multiple airports
|Muskegon, Muskegon County Airport, MI||40 mi||35 min||SW 8||10.00 mi||Partly Cloudy||77°F||68°F||74%||1014.1 hPa|
Wind History from MKG (wind in knots)
|1 day ago||SW||S||S||S||S||Calm||S||SW||SW||NW||Calm||SW||Calm||Calm||N||NE||NE||W||W||W||NW||W|
|2 days ago||W||NW||N||Calm||Calm||Calm||Calm||Calm||SW||Calm||Calm||NE||SE||Calm||Calm||W||SW||SW||W||W||SW||SW||SW |
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|Weather Map ||IR Satellite Image from GEOS|
GOES Local Image of GreatLakes EDIT
Wind Forecast for Grand Rapids, MI (18,4,5,8)(on/off)  Help
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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.