Saturday, October21, 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 7:58AMSunset 6:47PM Saturday October 21, 2017 11:40 AM EDT (15:40 UTC) Moonrise 8:37AMMoonset 7:15PM Illumination 2% Phase: Waxing Crescent; Moon at 1 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
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LMZ846 Holland To Grand Haven Mi- 319 Am Edt Sat Oct 21 2017
.small craft advisory in effect through Sunday evening...
Today..South winds 15 to 25 knots. Mostly Sunny. Waves 3 to 5 feet.
Tonight..South winds 20 to 25 knots. Partly cloudy. Waves 4 to 6 feet.
Sunday..South winds 15 to 25 knots veering west late in the day. A chance of showers until midday, then showers in the afternoon. Waves 4 to 6 feet.
Sunday night..Northwest winds 10 to 15 knots. Showers likely in the evening, then partly cloudy with a chance of showers overnight. Waves 2 to 4 feet subsiding to 1 to 3 feet after midnight.
LMZ846 Expires:201710211515;;172631 FZUS53 KGRR 210719 NSHGRR Nearshore Marine Forecast National Weather Service Grand Rapids MI 319 AM EDT Sat Oct 21 2017 For waters within five nautical miles of shore on Lake Michigan LMZ846-211515-

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


Area Discussion for - Grand Rapids, MI
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Fxus63 kgrr 211107
afdgrr
area forecast discussion
national weather service grand rapids mi
707 am edt Sat oct 21 2017
latest update...

aviation

Synopsis
Issued at 312 am edt Sat oct 21 2017
after a very warm Saturday with highs approaching 80 in spots, the
forecast changes dramatically Sunday with rain showers. Precipitation,
possibly heavy in some spots, is expect to last well into the coming
week. Monday night through Tuesday looks particularly wet with
increasing winds associated with a regardless of the details, there
is increasing potential for significant rain beginning Monday night
and lasting well into Tuesday. We have bumped up precipitation
totals over the eastern forecast area with this update in response
to these model trends. Strengthening fall storm. Temperatures next
week will be seasonably cool with highs in the upper 40s to mid 50s.

Short term (today through Monday night)
issued at 312 am edt Sat oct 21 2017
rain is still expected to overspread the area Sunday and prospects
are increasing for significant rain beginning Monday night and
lasting well into Tuesday. We have bumped up precipitation totals
over the eastern forecast area with this update in response to
these model trends.

High confidence for widespread rain moving across the area Sunday.

Impressive moisture fetch off the gulf feeding into this system
is supported by Friday evening soundings with precipitable water
greater than 200 percent of normal in parts of the southern and
central plains. Favored ece ensemble guidance shows some, but mostly
minor, variability with timing and extent of the rain showers moving
east into the forecast area early Sunday. This precipitation
should be an extensive north to south band that is slow moving and
likely to produce heavy precipitation. This character of
precipitation can often alter low level winds moist transport
vectors via low level PV generation associated with significant
latent heat release. This subsequently can alter the evolution and
intensity of the precipitation band. Models can't typically
account for these diabatic PV processes well, which might explain
the position and intensity differences seen in the ensemble
members.

We expect a bit of a lull in precipitation Monday as the
preponderance of ensemble members move this band just east of the
area. However, Monday night looks quite interesting with several
ece members showing an impressive trowal with significant rainfall
wrapping back into the forecast area. Even though the 21 00z
deterministic ECMWF is farther east and drier for our area,
several of the 20 12z ece members showed a wide variety of
solutions, many of which affect our area. This is to be expected
because the predictability of this feature depends on what happens
Sunday. The 21 00z ensemble will be interesting to see, but the
expectation is that there will still be many members showing a
trowal over our area. Regardless of the details, there is
increasing potential for significant rain Monday night into
Tuesday.

Otherwise, today looks very warm again similar to Friday so have
bumped temperatures up accordingly.

Long term (Tuesday through Friday)
issued at 312 am edt Sat oct 21 2017
this is the time of year when the jet stream begins to take some
plunges farther south across the country and synoptic systems become
much more amplified. That'll be the case this week as a deep upper
trough develops over the great lakes Tuesday. A short wave over the
deep south will get kicked northward by the stronger trough moving
across the upper midwest. The resulting surface system will move
northeast to southeast ontario Tuesday morning. We're going to see
showers Tuesday as the trough moves across the state. Temperatures
will be much cooler with highs in the lower 50s. Lingering rain
showers Tuesday night may mix with wet snow over the far northeast
cwa as temperatures fall into the 30s. A chilly day with highs in
the 40s is expected Wednesday.

Another short wave following closely on the heels of the deep trough
will keep showers in the forecast Wednesday, after which weak
ridging moves over the state. However, another series of short waves
will move over the northern plains and great lakes helping to keep
the long wave trough in place, which means highs will be closer to
normal in the mid 50s.

Aviation (for the 12z tafs through 12z Sunday morning)
issued at 707 am edt Sat oct 21 2017
very high confidence forVFR conditions through 00z and high
confidence through 12z Sunday. Cloud bases today should remain
well above 12000 ft agl. Main concern early this morning and
particularly tonight is low level wind shear with winds from the
southwest possibly reaching 50 knots or more within 2000-3000 ft
agl. Precipitation is expected to move east into the area Sunday
morning, most likely well after 12z.

Marine
Issued at 312 am edt Sat oct 21 2017
based on ww3 guidance, have expanded small craft advisory
southward to holland. With strong and persistent winds from the
south, waves are expected to remain at SCA levels well into
Sunday. Even more significant winds and waves will be possible
towards the middle of next week due to increasing chances for a
fall storm centered around lake huron.

Hydrology
Issued at 147 pm edt Fri oct 20 2017
dry weather will persist through Saturday. A cold front passing
through the region will then provide a high coverage of showers
Sunday and Sunday night. Rainfall amounts will generally run about
0.50 inches, but locally heavier pockets of rain will exist. These
pockets could bring rain amounts in excess of one inch. These
heavier amounts could cause rivers, creeks, and streams to rise,
especially in the kalamazoo river basin where water levels are still
high following heavy rain last weekend.

The frontal boundary may then stall over either michigan or the
eastern great lakes Monday into Tuesday, and become a focus for
additional rainfall. This rainfall could potentially become heavy
(over an inch of rain) and could lead to additional rises in rivers,
creeks, and streams. Changes to the rainfall forecast Monday into
Tuesday are possible.

Grr watches warnings advisories
Mi... None.

Lm... Small craft advisory until 8 pm edt Sunday for lmz846>849.

Synopsis... Tjt
short term... Tjt
long term... 04
aviation... Tjt
hydrology... Hlo
marine... Tjt


Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
HLNM4 - 9087031 - Holland, MI 78 mi40 min S 19 G 23 1018.7 hPa (+0.0)
MKGM4 - Muskegon, MI 90 mi30 min S 18 G 22 63°F 1018.7 hPa53°F
SBLM4 - Saginaw Bay Light #1, MI 91 mi40 min S 13 G 14 60°F 1020.7 hPa (+0.4)

Wind History for Holland, MI
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Capital Region International Airport, MI8 mi47 minSSW 910.00 miFair67°F50°F55%1021.7 hPa
Charlotte, Fitch H Beach Airport, MI13 mi45 minSSW 1310.00 miFair67°F50°F55%1021.3 hPa
Mason, Mason Jewett Field Airport, MI21 mi46 minN 010.00 miFair66°F52°F61%1022.3 hPa
Ionia County Airport, MI21 mi44 minSSW 1110.00 miFair65°F48°F55%1021 hPa

Wind History from LAN (wind in knots)
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1 day agoW11W11W10W14
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W14W12W9W6W6W4W5W4CalmCalmCalmCalmCalmCalmSE3CalmSE3S4S7S7
2 days agoSW14
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S9S9S8S7S8SW11SW11SW10SW14SW11SW11SW10SW11SW9SW9W10W10W9

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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Weather Map
wmap_A
IR Satellite Image from GEOS
east_satellite

GOES Local Image of GreatLakes    EDIT
Geos

Wind Forecast for Grand Rapids, MI (11,2,3,4)
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Ground Weather Radar Station Detroit, MI
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weather_mapweather_map weather_map

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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.