Wednesday, September20, 2017 L-36.com


Marine Weather and Tides
Mackinaw City, 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 7:21AMSunset 7:39PM Wednesday September 20, 2017 9:04 AM EDT (13:04 UTC) Moonrise 6:39AMMoonset 7:13PM Illumination 0% Phase: New Moon; Moon at 29 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
LHZ345 Straits Of Mackinac Within 5 Nm Of Mackinac Bridge Including Mackinac Island- 351 Am Edt Wed Sep 20 2017
Today..Southeast wind 10 to 15 knots. Mostly cloudy early in the morning then becoming mostly Sunny. Waves 2 feet or less.
Tonight..Southeast wind 5 to 10 knots. Chance of showers and Thunderstorms. Waves 2 feet or less.
Thursday..Light winds. Partly Sunny. Waves 2 feet or less.
Thursday night..Light winds. Chance of showers. Waves 2 feet or less. Winds and waves higher in the vicinity of Thunderstorms. SEe the open lakes forecast for days 3 through 5.
LHZ345 Expires:201709201600;;654083 FZUS53 KAPX 200751 NSHAPX Nearshore Marine Forecast National Weather Service Gaylord MI 351 AM EDT Wed Sep 20 2017 For waters within five nautical miles of shore on Lakes Huron... Michigan and Superior LHZ345-201600-

7 Day Forecast for Marine Location Near Mackinaw City, MI
   Hourly   EDIT   Help
location: 45.78, -84.76     debug


Area Discussion for - Gaylord, MI
      (on/off)   Help   NOTE: mouseover dotted underlined text for definition
Fxus63 kapx 201048
afdapx
area forecast discussion
national weather service gaylord mi
648 am edt Wed sep 20 2017

Update
Issued at 611 am edt Wed sep 20 2017
a few showers have popped up over NE lower mi and lk huron. The
question why is a challenge to answer, but there is a nearly
stationary vort MAX hanging over the thumb area and southern lk
huron (left over from last nights convection). Recent rap runs
hang onto some showers over NE lower mi and vicinity thru mid
morning before diminishing, and will have something similar in the
updated grids fcst.

Near term (today through tonight)
issued at 337 am edt Wed sep 20 2017

Shower and thunderstorm threat increases tonight...

high impact weather potential... Some non-svr t-storms tonight,
especially overnight.

Upstream cold front is pushing across central mn early this
morning. Line of deep convection accompanies this front. Parent
forcing shortwave is lifting nne toward hudson bay. So the cold
front will become a bit mushier by the time it is pushing into
eastern upper and approaching NW lower mi very late tonight.

Still, there is a respectable chance for precip ahead of this
front tonight.

In the meantime, cloud cover and temps are the main challenges for
the daylight hours. Stratus has advected into the region on ese sub-
850mb winds. Downsloping is keeping this deck is bit tattered along
the NW lower mi coast, but elsewhere it's pretty solid. We'll be
able to get diurnal heating around its edges and thru thin spots to
erode this deck, but our Sun angle isn't what it used to be, and
this will take time. Will generally hang onto mostly cloudy skies
into early afternoon east of i-75 in both peninsulas, with rapid
improvement thereafter. With the above in mind, will also cut
down on guidance MAX temps a touch in eastern sections.

Improvement will be faster west of i-75.

Highs will be mid 70s to lower 80s, warmest west of m-66. Immediate
tvc area may hit the mid 80s.

Prominent pre-frontal instability plume will develop across wi and
western central upper mi this afternoon, in a relatively narrow zone
of deeper moisture return. Shower thunderstorm activity is expected
there, per SPC day 1 outlook. This activity not be as vigorous as it
is presently, as again better forcing is lifting nne into canada.

Low-level convergence will be less, and mid-level cooling height
falls will diminish, leading to some concerns about capping. Still,
some activity is likely upstream, organizing into linear segments.

Instability plume will pivot into northern mi tonight, especially
overnight, as 1000-850mb SW flow increases. MUCAPE values will push
1k j kg in NW lower mi, less elsewhere.

Expect a chance of convection reaching far western mack co, and W of
tvc-cad, by mid late evening. Chance for showers storms will
gradually expand eastward across northern mi during the night. Will
have likely pops only for a portion of eastern upper mi, centered on
midnight to early overnight. Elevated nature of convection, and
decreasing instability with time, will limit any svr threat this far
east. Better shear (0-6 km bulk shear of 30-40kt) is in eastern
upper mi overnight, displaced spatially and temporally from better
instability.

A warm and sticky night, with min temps near 60f to the mid 60s.

Some foggy spots are likely overnight, especially where it rains.

Short term (Thursday through Friday)
issued at 337 am edt Wed sep 20 2017

Weak frontal passage to provide a little rain Thursday...

high impact weather potential... Minimal, as thunder threatens on
Thursday Thursday night.

Pattern synopsis forecast... Thursday morning around 12z, the cold
front looks to be about half way through the forecast area, and will
probably have a few showers around in the morning. However, during
the afternoon the sfc high has moved NE and the next sfc low pushes
the cold front north as a warm front. Both the ECMWF and the gfs,
not to mention the SREF kick off the rain showers and thunderstorms
over the state. The dirty ridge idea overnight that the GFS has been
advertising, the ECMWF now shows overnight as well. Friday looks to
be more precipitation free as the models continue to pump up the
ridge as the ECMWF was advertising over the last few days. This sets
us up for a drier weekend.

Primary forecast concerns... This idea of a "dirty" ridge with the
moisture getting into it, and weak spokes of vorticity setting off
showers and thunderstorms, really is the question mark of the next
two days. While the Thursday looks more likely than Friday, the gfs
has shown little dots of QPF during Friday. Still think that the
ecmwf pumping up the ridge is the better idea, but based on the
evolution of the models over the Thursday Friday time frame the last
few nights, won't be surprised if isolated showers pop up on Friday.

Long term (Friday night through Tuesday)
issued at 337 am edt Wed sep 20 2017

Above normal temperatures and relatively precipitation free
through the weekend...

extended (Saturday through Tuesday)... I'm sounding like a broken
record as the GFS continues the look of a "dirty" ridge and the
ecmwf continues to keep the weekend dry as it pumps up the 500 mb
ridge. The ECMWF is still looking good into the early part of the
week and it seems that the GFS is beginning to latch onto the ecmwf
idea of maria absorbing the remnants of jose and going into mid
atlantic states helping to break down the ridge and allow the 500 mb
low in the N plains begin to move east into the upper great lakes.

So this will continue to pump up the heat in the upper great lakes
into Tuesday (numbers still trending almost 10 to 15f above normal)
with little precipitation until probably Tuesday or maybe Wednesday.

Aviation (for the 12z tafs through 12z Thursday morning)
issued at 648 am edt Wed sep 20 2017
ifr to lifr stratus deck (and some associated fog) blankets
northern lower mi. This will tend to erode from W to E this
morning and early afternoon, taking longest at apn. All sites will
eventually becomeVFR this afternoon. Incoming cold front will
spawn some showers and a few thunderstorms tonight, as well as a
return to some lower CIGS (especially toward dawn).

Light SE to S surface winds today, becoming light variable
tonight.

Marine
Issued at 337 am edt Wed sep 20 2017
current easterly winds will veer SE today, and S tonight, ahead of
a cold front that will reach eastern upper mi and surrounding
waters late tonight. Front will stall and wash out Thursday,
leading to south winds continuing on huron, with light variable
winds elsewhere. Winds waves will remain below advisory levels.

Apx watches warnings advisories
Mi... None.

Lh... None.

Lm... None.

Ls... None.

Update... Jz
near term... Jz
short term... Jl
long term... Jl
aviation... Jz
marine... Jz


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
MACM4 - 9075080 - Mackinaw City, MI 2 mi46 min S 1.9 G 2.9 64°F 1015.2 hPa59°F
45175 3 mi24 min S 1.9 G 1.9 65°F 64°F1016 hPa
45022 31 mi24 min E 9.7 G 14 64°F 66°F1 ft1016.7 hPa64°F
SRLM4 33 mi64 min 64°F 66°F62°F
NABM4 - Naubinway, MI 42 mi48 min SSE 9.9 G 16 65°F 1014.9 hPa
WNEM4 - 9076027 - West Neebish, MI 45 mi46 min ESE 1.9 G 4.1 63°F 1016.1 hPa60°F
RCKM4 - 9076024 - Rock Cut, MI 45 mi46 min ESE 7 G 9.9 1015.2 hPa
DTLM4 - 9075099 - De Tour Village, MI 48 mi46 min SE 6 G 8 65°F 1015.3 hPa65°F
PTIM4 - 9099004 - Point Iroquois, MI 49 mi46 min ESE 6 G 8.9 63°F 1016 hPa60°F

Wind History for Mackinaw City, 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
E9
SE12
G15
E13
SE16
E16
E14
G18
E12
SE14
SE15
SE14
E12
SE14
SE14
SE15
SE7
SE12
SE7
SE9
SE5
SE1
SE4
SE7
SE8
SE4
1 day
ago
N4
N5
NE5
E1
NE5
NE3
NE4
N6
NW4
N2
NW7
NW4
N5
S2
NE8
G11
NE7
NE3
NE2
E5
NE6
N6
E4
E8
E10
2 days
ago
SW10
G14
SW9
G15
SW8
G12
SW13
G19
SW7
G11
W13
G20
SW7
G13
W9
G15
W9
G13
NE17
G21
N12
G18
N8
N7
N7
G10
N8
N7
G10
N8
G11
NW7
G10
NW6
N4
N5
N5
G8
NW5
N7

Airport Reports
    EDIT      (on/off)   Help   Click EDIT to display multiple airports
AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Mackinac Island Airport, MI8 mi68 minESE 310.00 miOvercast66°F64°F98%1015.9 hPa
Pellston Regional Airport of Emmet County, MI14 mi70 minSSE 47.00 miOvercast64°F63°F96%1015.9 hPa
Cheboygan, Cheboygan County Airport, MI16 mi69 minN 01.00 miFog/Mist61°F60°F100%1015.6 hPa

Wind History from MCD (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 24hrE8
G14
E4E8
G16
E6
G15
E10
G15
E9
G16
E8
G17
E11
G16
E7E7
G14
E6SE6E6SE5SE6SE5SE5SE3CalmE4E3SE8SE4E3
1 day agoNW3N5N6NW5CalmW5SW4SW3W4SW4W4NW3NW4N5NE7NE6NE5NE6NE5N4CalmE6E7E6
2 days agoS7S8SW7SW8
G15
SW8W11
G17
W7W12NW7N10
G15
N11
G18
N11
G14
N10N8N6N6N7N5N5N4NW4NW5N4N3

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

Ground Weather Radar Station Gaylord, 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.