Friday, December15, 2017 L-36.com


Marine Weather and Tides
Roosevelt Park, MI

Version 3.4
What's New / NOTES
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 8:09AMSunset 5:12PM Friday December 15, 2017 9:10 AM EST (14:10 UTC) Moonrise 5:28AMMoonset 3:55PM Illumination 8% Phase: Waning Crescent; Moon at 27 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
LMZ847 Grand Haven To Whitehall Mi- 338 Am Est Fri Dec 15 2017
.small craft advisory in effect through late tonight...
Today..West winds to 30 knots. Snow showers until midday, then a chance of snow showers in the afternoon. Waves 6 to 8 feet.
Tonight..Northwest winds 15 to 25 knots becoming north 5 to 15 knots toward daybreak. A chance of snow in the evening, then snow likely overnight. Waves 5 to 7 feet subsiding to 2 to 4 feet toward daybreak.
Saturday..East winds 10 to 20 knots. Cloudy. A chance of snow until midday. Waves 1 to 3 feet.
Saturday night..East winds 15 to 20 knots. Mostly cloudy in the evening then becoming partly cloudy. Waves around 1 foot.
LMZ847 Expires:201712151615;;919502 FZUS53 KGRR 150838 NSHGRR Nearshore Marine Forecast National Weather Service Grand Rapids MI 338 AM EST Fri Dec 15 2017 For waters within five nautical miles of shore on Lake Michigan LMZ847-151615-

7 Day Forecast for Marine Location Near Roosevelt Park, MI
   Hourly   EDIT   Help
location: 43.22, -86.36     debug


Area Discussion for - Grand Rapids, MI
      (on/off)   Help   NOTE: mouseover dotted underlined text for definition
Fxus63 kgrr 151201
afdgrr
area forecast discussion
national weather service grand rapids mi
701 am est Fri dec 15 2017
latest update...

aviation

Synopsis
Issued at 330 am est Fri dec 15 2017
a burst of lake effect snow is expected this morning. The increase
in intensity of the snow is due to an upper level disturbance
swinging across lake michigan. Through the course of the afternoon
the snow should wind down. For a time this morning though, travel
conditions will be poor with limited visibility and slippery roads.

The peak in the snow will be right around the morning commute in
most areas. Snowfall should range from 1 to 3 inches for areas along
and west of u.S. Highway 131 and an inch or less to the east. Some
additional light snow is possible tonight into Saturday as a
weakening warm front moves our way. A weakening low may bring us
some rain and snow on Sunday as warmer air will have moved into the
region from the south. Highs will remain in the 20s again today, but
by Sunday we should be well into the 30s.

Short term (today through Sunday)
issued at 330 am est Fri dec 15 2017
focus in the short term is on three items... 1) a lake enhanced snow
event today, 2) the potential for a little warm air advection snow
tonight into Saturday and 3) a weakening low bringing precipitation
chances on Sunday.

The lake enhanced snow event today remains on track and made no
changes to the going winter weather advisory. If there is a trend in
the models from last night into tonight, it looks like snow totals
may be just a tad lower. 1 to 3 inches looks like it should cover
the bulk of the snow. The MAX in the event should be between now and
about 11am or so. The upper shortwave is seen in water vapor imagery
over northern wisconsin moving quickly toward central lake michigan.

This shortwave will give a boost to the lake effect snow through an
increasing depth of moisture and synoptic scale lift added to the
convective boundary layer. 925-850mb layer omega details why snow
totals will be held in check, which is the fact that the good lift
will be transitory across the western cwa. It is not sustained for
more than a few hours at any one location. Still, thinking impacts
can be expected as heavier snow bursts slicken up the roads right
around the time of the morning commute. The snow should wind down
this afternoon from west to east.

Tonight into Saturday a band of warm air advection snow will move
into the forecast area from the south. Trends have been for lesser
amounts to the snow. The weakening trend is due to the fact that the
low responsible for the warm air advection is filling with time as
it moves our direction. Thinking snowfall via this band will be an
inch or less.

On Sunday a surface low moves our direction from the south. The
upper shortwave associated with the low is moving into confluent
flow aloft and it is weakening with time. Have some rain and snow
showers in the forecast for Sunday afternoon, but model trends have
been for a weaker low and less in the way of precipitation. Impacts
should be nil as temperatures will be above freezing.

Most impactful weather in the short term will come this morning.

High temperatures will moderate some each day, with highs above
freezing in all areas by Sunday.

Long term (Sunday night through Thursday)
issued at 330 am est Fri dec 15 2017
relatively quiet to start the week as the flow remains zonal and we
will have a soft southerly flow. Sunday night and Monday may see
some areas of fog and patchy drizzle, otherwise temps will be near
to slightly above normal. Light warm advection rain showers may
occur ahead of a cold front Monday night that may mix with snow
across central lower. We will have to watch to see if the cold
shallow air is completely scoured out, since some light freezing
rain could also occur across the interior north.

We should be brushed by colder air in the Tue Wed time frame behind
the departing front and we briefly get into upper troughiness. Still
looks cold enough for a quick shot of lake effect snows mainly
Tuesday afternoon and evening.

Model differences arise toward the end of the forecast period. But
it does appear solid warm advection returns by Wednesday
night Thursday as upper troughing develops to our west, resulting
deep southwest flow. Surface low pressure develops in the plains
and heads for the great lakes into Thursday. After a mainly dry wed
we should see snow developing in the warm advection wing Wed night,
but this mixes and then eventually change to mostly rain into
Thursday as the low is expected to track somewhere near central lake
michigan by Thursday evening.

Aviation (for the 12z tafs through 12z Saturday morning)
issued at 701 am est Fri dec 15 2017
conditions are expected to dip into the MVFR category at all
locations this morning as lake effect snow showers sweep through
the TAF sites. Kgrr and kmkg will be most affected, where
conditions will dip to ifr at times through about 16z.

Visibilitieswill improve this afternoon toVFR in most area
although MVFR ceilings will linger in many areas.

West-southwest winds (240-260) will increase into the 12 to 25
knot range around 15-16z and remain at those levels until about
23z.

Tonight a band of snow will spread in from the south and
conditions should dip to MVFR again in all areas by Saturday at
12z.

Marine
Issued at 330 am est Fri dec 15 2017
we expect building wave heights today due to increasing westerly
winds behind the passage of a trough of low pressure. The peak of
the wind should be around 18z to 19z and the waves should MAX out
this afternoon as well. Solid 7 footers look likely this afternoon
and early evening. Maintained the small craft advisory as is which
is in effect through much of tonight. It will take some time tonight
before the wave field dampens out as the winds only slowly subside.

Winds are expected to remain below 20 knots through the weekend, so
a relative calm out of the lake for this time of year.

Hydrology
Issued at 330 pm est Thu dec 14 2017
many rivers have iced over pretty quickly due to the snow and cold
temperatures. The looking glass near eagle has risen above bankfull
due to downstream ice constricting the flow. It is expected to
gradually fall but some fluctuations are still possible. Mild
temperatures early next week may soften the ice a bit. Water frozen
in the snowpack ranges from 0.5 to 1 inch in most locations, but a
full snowmelt is not expected anytime soon.

Grr watches warnings advisories
Mi... Winter weather advisory until 4 pm est this afternoon for miz037-
038-043-044-050-056-057-064-065.

Lm... Small craft advisory until 5 am est Saturday for lmz844>849.

Synopsis... Duke
short term... Duke
long term... Jk
aviation... Duke
hydrology... Cas
marine... Duke


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
MKGM4 - Muskegon, MI 1 mi21 min NW 25 G 27 27°F 1011.3 hPa24°F
HLNM4 - 9087031 - Holland, MI 32 mi41 min W 22 G 29 1009.6 hPa
LDTM4 - 9087023 - Ludington, MI 50 mi41 min WNW 12 G 17 24°F 17°F

Wind History for Holland, MI
(wind in knots)    EDIT      (on/off)   Help
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
7
AM
8
AM
Last
24hr
SE5
SE3
SE4
S6
G9
S6
G9
S5
SE7
G10
SE5
W11
G14
W13
G17
W13
G18
W14
G17
W11
G14
W9
G14
W6
SW6
G11
SW10
SW11
G17
SW13
G18
SW15
G21
SW19
G23
SW22
W19
G25
W18
G26
1 day
ago
SE9
G15
E11
G15
SE15
G19
SE16
G21
E15
G21
E11
G17
E12
G15
E14
G17
NE17
G22
NE16
G21
NE14
G18
NE11
G19
N11
G18
N11
G17
N12
G17
N15
G19
N9
G14
N10
G14
NE7
G12
NE10
NE9
E3
E6
E9
2 days
ago
NW29
G36
NW29
G35
N17
G25
N9
G16
N19
G24
NW24
G33
NW25
G32
NW23
G34
NW24
G31
NW20
G28
NW20
G26
NW20
NW18
G22
NE4
G10
NE3
E5
G8
N4
W9
W9
G15
W7
G11
E4
SE6
G9
SE9
G12
SE12
G16

Airport Reports
    EDIT      (on/off)   Help   Click EDIT to display multiple airports
AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Muskegon, Muskegon County Airport, MI6 mi16 minWNW 14 G 202.50 miLight Snow27°F21°F78%1010.3 hPa

Wind History from MKG (wind in knots)
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
7
AM
8
AM
9
AM
Last 24hrE3CalmSE4S4SE5E5SE4SE4SE6W5NW5W4W4SW3E4E3CalmSW9SW10
G18
SW15
G19
W13
G21
W10W12W14
G20
1 day agoSE13
G22
SE16E21
G25
E14
G21
E13E13E17
G23
E12E11NE11N10N13
G19
N8
G16
N15
G18
N10N12N6N4N4CalmCalmCalmE3SE3
2 days agoNW14N19N17
G26
NW15
G23
N17N13N16
G23
N13N9N9N9N5E3CalmSE3SE5SE5SE7SE7SE7SE9SE10SE11SE16

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 Grand Rapids, MI (9,2,3,4)
      (on/off)   Help

Ground Weather Radar Station Grand Rapids/Muskegon, MI
   (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.