Monday, August21, 2017 L-36.com


Marine Weather and Tides
Grand Marais, MN

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 6:59AMSunset 9:00PM Monday August 21, 2017 11:20 PM EDT (03:20 UTC) Moonrise 5:46AMMoonset 8:07PM 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
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LSZ162 Lake Superior West Of A Line From Saxon Harbor Wi To Grand Portage Mn Beyond 5nm- 1007 Pm Edt Mon Aug 21 2017 /907 Pm Cdt Mon Aug 21 2017/
Rest of tonight..East winds 5 to 15 knots becoming north 10 to 20 knots after midnight, then backing northwest late. Waves calm to 2 feet.
Tuesday..Northwest winds 15 to 25 knots backing west in the afternoon. Waves building to 1 to 3 feet.
Tuesday night..Northwest winds 15 to 25 knots diminishing to 10 to 20 knots after midnight, then veering north late. Waves subsiding to calm to 2 feet.
Wednesday..North winds 5 to 15 knots backing west by mid afternoon. Waves calm to 2 feet.
Wednesday night..West winds 5 to 15 knots veering north after midnight. Waves calm to 2 feet.
Thursday..East winds 5 to 15 knots. Waves calm to 2 feet.
Thursday night..East winds 5 to 15 knots. Waves calm to 2 feet.
Friday..East winds 5 to 15 knots. Waves calm to 2 feet.
Saturday..Southeast winds 10 to 20 knots. A chance of showers. Waves calm to 2 feet.
LSZ162 Expires:201708221015;;752452 FZUS63 KMQT 220213 CCA GLFLS Open Lake Forecast for Lake Superior...CORRECTED National Weather Service Marquette MI 1012 PM EDT Mon Aug 21 2017 For waters beyond five nautical miles of shore on Lake Superior Waves are the significant wave height - the average of the highest 1/3 of the wave spectrum. Occasional wave height is the average of the highest 1/10 of the wave spectrum. .SYNOPSIS...30.0 high pressure over northwestern Lake Superior this evening will move across the Upper Great Lakes tonight. Low pressure of 29.8 inches over the Central Plains will move through northern Lake Huron by early Tuesday. A 30.2 inch high pressure extending from Manitoba to Nebraska Tuesday night will move over Wisconsin Thursday morning and remain over the Great Lakes through Friday and into Saturday. LSZ162-221015-

7 Day Forecast for Marine Location Near Grand Marais city, MN
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location: 47.86, -89.87     debug


Area Discussion for - Duluth, MN
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Fxus63 kdlh 212344
afddlh
area forecast discussion
national weather service duluth mn
644 pm cdt Mon aug 21 2017

Update
Issued at 630 pm cdt Mon aug 21 2017
have updated for the showers blooming across the area this evening
in an area of instability ahead that has developed along and ahead
of an inverted trough and shortwave that is going to be moving
through the area this evening. In general have increased both pops
and cloud coverage, with some thunder across the southern forecast
area. Also... Updated aviation section below for 00z TAF taf
issuance.

Short term (this evening through Tuesday)
issued at 321 pm cdt Mon aug 21 2017
an approaching upper-level trough, and embedded shortwaves within
the westerly flow aloft, are and will be bringing areas of
forcing for ascent across the northland through this evening.

Passing surface low pressure across the southern forecast area
will likely interact with this forcing to help produce some
showers and storms across northwest wisconsin late this afternoon
through this evening. The storms should be relatively weak, but
there could be some stronger storms near price county capable of
gusty winds and small hail. The storms could have brief downpours
of rain considering the deep moisture in the atmosphere, with
precipitable water values around 1.5 inches.

Also, the main upper-trough will swing through the northland this
evening and overnight. It could bring a period of clouds and some
light rain over the western forecast area. Drier and cooler air
will filter into the northland amidst the northwest flow
overnight. There should be a clearing trend later tonight. The
winds might be light enough in the early morning to result in some
patchy fog. Lows will range from the upper 40s to lower 50s.

The northland will be in cool northwest flow Tuesday. Sunny skies
in the morning will quickly heat things up and deep mixing will
develop by the afternoon. Windy conditions will develop. The gfs,
nam, and regional canadian models are suggesting the mixing will
be strong enough to draw down 20 to 30 mph flow from aloft. Have
widespread 20 to 25 mph gusts in the afternoon, and some areas
will see occasional gusts to 30 mph, like in duluth. A weak cool
front will dip into far northern minnesota in the late afternoon,
and some light showers will likely develop up there. Highs should
be in the upper 60s and lower 70s.

Long term (Tuesday night through Monday)
issued at 321 pm cdt Mon aug 21 2017
cooler mid to late week with a chance for rain showers this
weekend.

On the synoptic scale northwest flow will prevail across the
upper midwest mid to late week as a longwave mid-level ridge
approaches the great plains. A broad area of high pressure will
build over the upper great lakes, then track eastward this
weekend. A chance for a quick-moving mid-level shortwave to bring
a round of showers late Wednesday or early Thursday, though
confidence in exactly where rain would fall is below normal. A
warm front lifting northeast towards the region on Friday will
lead to increasing clouds and a chance for showers, then
additional chances for precipitation Saturday as a cold front
moves though. Model differences through the weekend lead to a long
period with chances for rain showers, but most solutions are not
a washout for all locations. A few thunderstorms are possible
Saturday and Sunday as the front moves through, but at this point
the threat for storms does not seem sufficient to include a
mention in the forecast.

Temperatures will be cooler than usual mid to late week with
highs in the 60s to near 70 through the long term period. As cool
as the mid 30s for parts of far northern minnesota, though
depending on the track of the mid-level wave coming through
Wednesday night temperatures may not fall as cold as currently
anticipated. Otherwise lows in the 40s to 50s.

Aviation (for the 00z tafs through 00z Tuesday evening)
issued at 630 pm cdt Mon aug 21 2017
showers and a few thunderstorms are moving across the area this
evening, and will continue for at least a few hours as an
inverted trough and upper level shortwave moves across the area.

While sites are generallyVFR, showers thunderstorms may bring a
period of MVFR ceilings with ifr visibilities to each site as they
move across. There may also be a period of MVFR ceilings that
linger behind the showers thunderstorms, but these should clear no
later than 04z most sites, but linger longer at khyr where it may
linger as late as 10z. Otherwise,VFR conditions are expected to
return for the remainder of the TAF period. Northwest winds are
expected to increase after 14z, and should blow around 15 kts with
gusts in the 20-25kt range.

Preliminary point temps pops
Dlh 52 71 50 66 40 0 0 10
inl 47 70 45 67 40 20 0 10
brd 53 72 49 68 10 0 0 20
hyr 51 71 48 67 40 0 0 10
asx 54 72 51 67 40 0 0 10

Dlh watches warnings advisories
Wi... None.

Mn... None.

Ls... None.

Update... Le
short term... Grochocinski
long term... Jjm
aviation... Le


Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
KGNA 26 mi84 min Calm 60°F 1009.6 hPa57°F
GD5 - 9099090 - Grand Marais, MN 26 mi50 min 61°F 1009.4 hPa60°F
ROAM4 - Rock of Ages, MI 30 mi80 min ENE 6 G 7 62°F 1011.7 hPa (-1.3)
45006 - W SUPERIOR 48NM North of Ironwood, MI 37 mi90 min NE 7.8 G 9.7 63°F 60°F1009.5 hPa (-2.1)
DISW3 - Devils Island, WI 71 mi80 min N 6 G 7 61°F 1011.2 hPa (-0.7)59°F

Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Grand Marais/Cook County Airport, MN27 mi73 minN 010.00 miLight Rain57°F51°F82%1011.5 hPa

Wind History from CKC (wind in knots)
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Last 24hrCalmCalmNW4NW3NW6NW5CalmCalmN3CalmCalmCalmCalmSW5CalmCalmCalmCalmCalmN3CalmCalmN4Calm
1 day agoW3W3W3W3W3CalmCalmCalmS3CalmS6SW8
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2 days agoW4N6CalmCalmW4W3CalmCalmCalmCalmCalmW4W7CalmW7W6NW3W6W3S4CalmCalmSW3W3

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 Duluth, MN (23,6,7,8)
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Ground Weather Radar Station Marquette, 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.