Friday, December15, 2017 L-36.com


Marine Weather and Tides
Grand Ledge, 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 8:01AMSunset 5:07PM Friday December 15, 2017 6:48 PM EST (23:48 UTC) Moonrise 5:20AMMoonset 3:50PM Illumination 6% 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
LMZ846 Holland To Grand Haven Mi- 333 Pm Est Fri Dec 15 2017
.small craft advisory in effect through late tonight...
Tonight..West winds 15 to 25 knots. Cloudy with a chance of snow showers. Waves 5 to 7 feet subsiding to 2 to 4 feet toward daybreak.
Saturday..East winds 5 to 15 knots. Cloudy. A chance of snow until midday. Waves 2 to 3 feet.
Saturday night..East winds 15 to 20 knots. Mostly cloudy in the evening then becoming partly cloudy. Waves 1 to 2 feet.
Sunday..Southeast winds 10 to 20 knots veering southwest late in the day. Mostly cloudy. A chance of rain and snow showers in the afternoon. Waves around 1 foot building to 2 to 4 feet late in the day.
LMZ846 Expires:201712160415;;944330 FZUS53 KGRR 152033 NSHGRR Nearshore Marine Forecast National Weather Service Grand Rapids MI 333 PM EST Fri Dec 15 2017 For waters within five nautical miles of shore on Lake Michigan LMZ846-160415-

7 Day Forecast for Marine Location Near Grand Ledge, MI
   Hourly   EDIT   Help
location: 42.75, -84.75     debug


Area Discussion for - Grand Rapids, MI
      (on/off)   Help   NOTE: mouseover dotted underlined text for definition
Fxus63 kgrr 152318
afdgrr
area forecast discussion
national weather service grand rapids mi
618 pm est Fri dec 15 2017
latest update...

aviation

Synopsis
Issued at 322 pm est Fri dec 15 2017
the lake effect snow showers that impacted the area this morning are
diminishing this afternoon. This will continue into early this
evening. Another band of light snow will develop this evening south
of i-96, and will migrate north through Saturday morning before
ending. 1 to 3 inches of new snow will be likely.

A lull in the snow is expected then Saturday night and early Sunday.

Precipitation chances will increase once again later Sunday. The
precipitation will start as some rain or snow as warmer air moves
in, and continue through Monday night before ending.

Short term (this evening through Sunday night)
issued at 322 pm est Fri dec 15 2017
our main focus of the short term is now the light snow expected
tonight, and then p-type questions for Sunday and Sunday night. The
advisory for today will be allowed to expire on time with the new
forecast package.

Lake effect snow showers are on the declining trend this afternoon
with regards to intensity and coverage as expected. The short wave
that helped the uptick today, is now moving east of the area. This
is driving down the inversion heights for a bit.

The break in snow will be short lived, especially for the srn
portion of the cwfa. We will see a sfc trough cold front over the
central portion of the area, drive south to i-94 this evening before
stalling. It stalls out as upper heights start to build also this
evening. We will see a wave of moisture transport translate along
the front and develop a band of light snow.

This looks to develop a NW to SE band of light snow later this
evening, that will gradually shift north to be centered around i-96
by Sat morning. This does not look to be significant enough to
warrant another advisory, but will drop 1-3 inches over a 12-18 hour
time frame. It will end as the wave moves east of the area sat
afternoon.

The next situation will be incoming pcpn late Sun and Sun night. We
will see a short wave across the central and southern plains lift ne
into the area. This wave will be different from the series of waves
we have seen over the past couple of weeks since it will be coming
from the sw. This will allow warmer air to push up into the area.

The pcpn may start out as some snow initially. It will tend to
change over with a SW low level flow advecting above freezing air,
and a sufficient melting layer depth to likely change it over to
rain for at least SRN areas Sun night as temps warm.

It does not look like this system will produce significant impacts.

We will monitor it in case temps do not warm quick enough, and p-
type becomes a problem.

Long term (Monday through Friday)
issued at 322 pm est Fri dec 15 2017
active pattern continues in the extended with two lows moving
through separated by a period of lake effect snow.

The first storm early in the week does not look to have much impact
as the southern stream moisture remains well separated from the
dominant northern stream and the sfc low passes well north of the
forecast area. Cold front comes through Monday night with cold
advection and lake effect snow showers Tuesday and Tuesday night
then tapering off Wednesday as warm advection begins ahead of the
next low. Bumped up superblend pops for lake effect snow showers
during this time period.

The second low comes through Thursday into Friday and continues to
have a lot of ensemble spread between a further north, stronger low
and a weaker, more southern track that would be colder with mostly
snow instead of mostly rain. The 12z operational GFS and ECMWF have
flip flopped with each other since yesterday with the ECMWF now
having the less amplified, colder solution. Did not make any changes
to the pops or temperatures during this time as the blend still
looks like a good compromise.

Looking beyond Friday and to december 25th... The overall synoptic
pattern shows a polar vortex across eastern canada and a SE conus
upper ridge. There is a very impressive temperature gradient between
the great lakes and central atlantic coast, with arctic air and 850
mb temperatures of -20c in lower michigan and a balmy plus 12c near
cape hatteras.

We will have to closely watch where the southern edge of the arctic
air and tropical moisture feeding up from the gulf meet. At this
point it appears we will be solidly in the cold air with some lake
effect snow showers while there could be a band of heavy freezing
rain somewhere to our south... Potentially across the ohio valley.

Aviation (for the 00z tafs through 00z Saturday evening)
issued at 618 pm est Fri dec 15 2017
as the current round of lake enhanced snow showers come to an end,
a band of warm advection snow will spread northward though the taf
sites overnight. The i-94 TAF sites will have only light snow, and
that will mostly be prior to 08z. With the heaviest snow being in
the 03z to 06z time frame. Meanwhile for i-96 TAF sites the band
snow will last longer and have heavier snow assoicated with it.

It should be solid ifr for mkg, grr and lan for at least 6 hours
(06z through 12z).

After the snow ends, the i-94 TAF sites may see the low clouds
break up and ceilings beVFR, on the other hand, for the i-96 taf
sites I could see solid ifr CIGS maybe even some fog. This could
be problem if surface temperatures stay below freezing (more than
likely will).

Marine
Issued at 322 pm est Fri dec 15 2017
we will be allowing the current small craft advisory to go on as is
for now. Most of the current obs along the shore continue to support
advisory conditions. Winds will gradually ease up, and waves will
slowly follow suit. The 5 am expiration time looks good at this
point.

Hydrology
Issued at 322 pm est Fri dec 15 2017
many rivers have iced over 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. High temperatures
above freezing early next week will 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... None.

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

Synopsis... Njj
short term... Njj
long term... Ostuno
aviation... Wdm
hydrology... Cas
marine... Njj


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
HLNM4 - 9087031 - Holland, MI 78 mi48 min W 22 G 27 1010.7 hPa (+0.8)
MKGM4 - Muskegon, MI 90 mi38 min NW 26 G 30 29°F 1012.6 hPa20°F
SBLM4 - Saginaw Bay Light #1, MI 91 mi48 min W 18 G 24 24°F 1008.1 hPa (+2.0)

Wind History for Holland, MI
(wind in knots)    EDIT      (on/off)   Help
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
10
AM
11
AM
12
PM
1
PM
2
PM
3
PM
4
PM
5
PM
6
PM
Last
24hr
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
W21
G27
W26
W24
G31
NW22
G28
W22
G27
W23
G28
W23
G28
W27
W30
W22
G27
1 day
ago
NE14
G18
NE11
G19
N11
G18
N11
G17
N12
G17
N15
G19
N9
G14
N10
G14
NE7
G12
NE10
NE9
E3
E6
E9
SE5
SE3
SE4
S6
G9
S6
G9
S5
SE7
G10
SE5
W11
G14
W13
G17
2 days
ago
NW20
G26
NW20
NW18
G22
NE4
G10
NE3
E5
G8
N4
W9
W9
G15
W7
G11
E4
SE6
G9
SE9
G12
SE12
G16
SE9
G15
E11
G15
SE15
G19
SE16
G21
E15
G21
E11
G17
E12
G15
E14
G17
NE17
G22
NE16
G21

Airport Reports
    EDIT      (on/off)   Help   Click EDIT to display multiple airports
AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Capital Region International Airport, MI8 mi55 minW 94.00 miFog/Mist24°F19°F84%1012 hPa
Charlotte, Fitch H Beach Airport, MI13 mi53 minWSW 610.00 miOvercast26°F15°F66%1010.2 hPa
Mason, Mason Jewett Field Airport, MI21 mi53 minW 610.00 miOvercast26°F15°F65%1010.5 hPa
Ionia County Airport, MI21 mi53 minW 710.00 miMostly Cloudy25°F17°F75%1010.2 hPa

Wind History from LAN (wind in knots)
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
10
AM
11
AM
12
PM
1
PM
2
PM
3
PM
4
PM
5
PM
6
PM
Last 24hrS8SW9SW9SW5SW6SW6SW4S6S8S7S9S9S9S8SW12SW11SW12SW13SW9W11W10W15W11W9
1 day agoE9NE11NE14NE14N13
G19
N9N12N10NW11NW6NW5NW6W4CalmCalmW5W4CalmS3CalmCalmW5SW7SW5
2 days agoNW10W9W7W10W5W6W5W4SW6SW7SW6S7S8S9SE9S10S10SE13SE14SE11E12E9E10E9

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 (18,4,5,8)
      (on/off)   Help

Ground Weather Radar Station Detroit, 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.