Marine Forecasts

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7 Day Forecast for Marine Location Near Pinconning, MI

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Area Discussion for - Detroit/Pontiac, MI

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Fxus63 kdtx 211602 afddtx area forecast discussion national weather service detroit pontiac mi 1202 pm edt Wed aug 21 2019 Update Southeast michigan is in the mid level subsidence bubble left over in the wake of the upper level PV tracking into the mid atlantic states. The surface near surface moisture is running high however, with dew pts around 70 degrees. Temperatures pushing 80 degrees at the noon hour, allowing sbcapes to reach 2000 j kg and mlcapes around 1000 j kg. Mid level lapse rates remain very weak however, but will be steepening up late today. At the same time, 0-6 km bulk shear will be ramping up, especially north of i-69. So, there is some concern the cold front dropping south this afternoon may be able to produce isolated severe storms. However, the inversion speed bump around 10 kft and the dry mid level air may be too much to overcome, especially as as mixing layer depths increase with temps reaching well into the 80s, leading to surface near surface moisture to mix out and lower, limiting the CAPE values. Overall, the inherited forecast looked reasonable, and just a minor tweak made to sky pops made. Prev discussion Issued at 636 am edt Wed aug 21 2019 aviation... low stratus and fog has developed overnight, generally north of ptk. Clearing overnight interacted with ample low level moisture to produce this. There has been a fair amount of variability to the low stratus fog, which will only persist with the onset of daytime heating. The daytime mixing will allow this moisture to develop a sct to bkn CU field by afternoon. A cold front will push into the region from the north late this afternoon and early evening. Strong mid level capping suggests a very low probability (less than 20 pct) of convection at the terminals. The higher tsra chances will be across the thumb region and points east where mid level capping will be weaker. For dtw... The subtle downslope into metro detroit and later clearing of the mid cloud deck as thus far inhibited anything other some some brief MVFR type vsby in fog; which will erode shortly after taf issuance. Thunderstorm chances late this afternoon evening are expected to be confined to the far northeastern portions of the detroit airspace with stronger capping at dtw likely inhibiting convection at the airport. Dtw threshold probabilities... * moderate in ceilings at or below 5000 ft this afternoon and evening. * low in thunderstorms this evening. * low in crosswind thresholds being exceeded this evening. Prev discussion... issued at 352 am edt Wed aug 21 2019 discussion... another round of afternoon evening precipitation yesterday left the near-surface layer at or near saturation overnight with patchy fog developing this morning across much of the area. Expect the greatest coverage across the thumb and saginaw valley where clearing occurred earlier last night. Any fog or low clouds will mix out by mid-morning. A similar, albeit slightly cooler, air mass is in place today compared to yesterday, with dew points well into the 60s and 850mb temps in the mid teens c. Highs will reach the mid 80s upper 80s around metro detroit with heat indices in the upper 80s to lower

90s under partly cloudy skies. The upper low currently near james bay will drop a potent shortwave across the northern great lakes this afternoon and evening, which will force a cold front south across SE michigan by this evening. An unstable environment remains in place today, but model soundings indicate a decent cap in the 700-800mb layer which should hold off much convection given the lack of forcing. The cap is slightly weaker across the tri-cities and especially the thumb, and with better forcing arriving via the front, expect scattered showers and storms to develop in these regions this afternoon. The 50+ kt 500mb jet will sag south into the central great lakes and contribute to bulk shear on the order of 35-40 kt by the late afternoon early evening, coincident with peak heating and frontal passage. Progged cape values this afternoon reach about 1000 j kg. This may allow some stronger storms to develop primarily in the thumb with wind gusts in excess of 40 mph possible. The best window for this activity to occur will fall between 2 and 8pm. Any showers and storms will move out by this evening as the cold front pushes through. Drier northwest wind will usher in a cooler air mass tonight that persists through the late week. Just a slight chance of showers across the southern counties tomorrow afternoon as a disturbance moves along the frontal boundary stalled over the northern ohio valley. Another lobe of vorticity will drop from the canadian upper low tomorrow night into Friday, bringing a reinforcing shot of cool air. Highs Thursday through Saturday will reach the mid 70s with lows in the 50s. High pressure will drift across the region during this time, leading to quiet and pleasant conditions. Return flow sets up as the ridge axis passes to the east Sunday, allowing warmer and more seasonable air to return to the great lakes for early next week. The next chance for precipitation comes Monday as a midlevel low attempts to bring a surge of tropical moisture northward. Marine... a cold front will drop south across lake huron this afternoon before pushing into lake erie tonight. The front will trigger a few thunderstorms, mainly on southern lake huron. A few of these could be strong. Strengthening north-northwest winds will develop within the post frontal cold air advection tonight, especially on lake huron. There is moderate to high probabilities that wind gusts across lake huron will range between 25 and 30 knots tonight. This will result in hazardous conditions for small craft on the nearshore waters of lake huron. Strong high pressure will slowly expand into the great lakes from the north Thursday and Friday, leading to a gradual decrease in the winds and waves. Any agitated cumulus may be able to produce waterspouts later today into tonight across southern lake huron, lake st. Clair, and lake erie. Water temps are in the 70s near 80 in the western basin of lake erie and 850mb temps will fall to around 9 to 10c, providing plenty of instability. Convective cloud depths approaching 25 kft and relatively weak 850 mb winds both lend additional support. Dtx watches warnings advisories Mi... None. Lake huron... Small craft advisory from 8 pm this evening to noon edt Thursday for lhz441>443. Lake st clair... None. Michigan waters of lake erie... None. Update... ... .Sf aviation... ..Sc discussion... Tf marine... ... .Sc you can obtain your latest national weather service forecasts online at

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Weather Reporting Stations

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Stations	Dist	Age	Wind	Air Temp	Water Temp	Waves	Pressure	DewPt
SBLM4 - Saginaw Bay Light #1, MI	16 mi	46 min	WSW 14 G 15	72°F			1011.9 hPa (+0.7)
45163	27 mi	26 min	W 9.7 G 12	73°F	74°F	1 ft
GSLM4 - Gravelly Shoals Light MI	31 mi	66 min	SW 13 G 16	71°F			1012.9 hPa
TAWM4 - Tawas City, MI	46 mi	66 min	S 4.1 G 8	78°F			1012.2 hPa

Wind History for Harbor Beach, MI

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Airport Reports

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Airport	Dist	Age	Wind kt	Visibility	Sky/Weather	Temp	DewPt	Humidity	Pressure
Jack Barstow Airport, MI	15 mi	71 min	SW 8	10.00 mi	Mostly Cloudy	78°F	69°F	74%	1012.5 hPa
MBS International Airport, MI	16 mi	1.9 hrs	WSW 7	5.00 mi	Overcast with Haze	74°F	69°F	85%	1012.8 hPa
Saginaw County H W Browne Airport, MI	23 mi	71 min	SSW 7	10.00 mi	Overcast	77°F	69°F	79%	1012.9 hPa

Link to 5 minute data for KIKW

Wind History from IKW (wind in knots)

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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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GOES Local Image of    EDIT
NOTE: East coast views moved to GEOS-16. They are experimental and not well supported by NOAA so they may not be correct so be warned. This change required redoing a large amount of the GOES code. If the image you are expecting is not showing, please let me know. You may need to use the EDIT function to update your location.
Link to Loop

Other links: Northern Pacific     Contential US     Full GOES-East

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Wind Forecast for Detroit/Pontiac, MI (12,3,4,5)

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Ground Weather Radar Station Detroit, MI

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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.