Marine Forecasts

    EDIT      (on/off)   Help

---

7 Day Forecast for Marine Location Near Bay City, MI

   Hourly   EDIT   Help

---

Area Discussion for - Detroit/Pontiac, MI

      (on/off)   Help   NOTE: mouseover dotted underlined text for definition
FXUS63 KDTX 070453 AFDDTX

Area Forecast Discussion National Weather Service Detroit/Pontiac MI 1153 PM EST Fri Dec 6 2019

AVIATION.

Cold cyclonic flow will remain over Lower Michigan through tonight with composite longwave trough in place over far eastern North America. Differential anticyclonic vorticity advection with rising geopotential heights supports increasing high pressure over the region. Satellite trends show steady erosion of lower cloud stratus through the course of the evening. High cloud will move into the state on Saturday in response to increasing warm air advection aloft and remnant shortwave passing from the Dakotas down through the Great Lakes. VFR conditions. Low confidence in any MVFR boundary layer cloud for Saturday.

DTW THRESHOLD PROBABILITIES .

* Low for cigs aob 5000 feet tonight and Saturday.

PREV DISCUSSION. Issued at 343 PM EST Fri Dec 6 2019

DISCUSSION .

Anticyclonic flow in place with active isentropic downglide will continue to produce dry weather throughout the bulk of the cwa with the exception of the northern portion of the Thumb, where a slight chance for an isolated snow shower will exist. Advancing moisture off of Lake Superior/Huron & sufficient CAPE/potential instability (for winter standards) may be just enough to produce the aforementioned snow shower, however, a dry sub-cloud layer and weak forcing will be a limiting factor. Overall, no accumulation is expected, and all PoP chances diminish after 00Z.

Approaching ridge axis and lowering inversion heights to aid in scouring out some lake effect cloud cover this evening and overnight as the 1028 mb low tracks across the Ohio Valley. Some radiational cooling and ongoing northwesterly flow will help support overnight lows in the upper-teens across the northern cwa and lower-20s across the urban Metro area before return flow from the departing high allows mid-level clouds to fill back in across the state. Mid-level cloud cover to hold on through the bulk of the morning and likely early afternoon before southerly flow pulls cloud cover to the north. Expecting another dry day under the influence of high pressure, but have added a very low-end chance for PoPs across the Tri-Cities given the latest ECMWF solution, where weak waa/isentropic interacts with a glancing shortwave. Given high cloud bases and subsequent dry air below, it will remain hard to come by any precipitation. Otherwise, flow turning zonal in the mid-levels and advancing clouds will help keep temperatures in the 30s for a high.

Attention will then turn to Sunday, where return flow from high pressure located the western Atlantic will start to stream in Gulf moisture and increase waa with h850 temperatures rising from an average of -7C (Sat 12Z) to 2C (Sun 12Z). Resulting daytime highs look to peak in the mid to upper-40s across the Metro area and low to mid-40s across the Tri-Cities and Thumb. Efficient transport of warmer air and moisture will be aided by a 40-50 knot LLJ setting up over the Great Lakes as a stationary front sets up across lower MI. Series of shortwaves advancing through the mean trough and PW rising toward .80 inches will be more than sufficient to produce widespread rain late Sunday through Monday. Continued SW flow will help support a second day in the 40s on Monday (peaking near 50 closer to MI/OH border). Passage of the low is projected to travel across northern lower Michigan late Monday into Tuesday, allowing a deep thermal trough to start to build in across the region. A transition from rain to snow will be possible on the back end of the system early Tuesday, before moisture axis moves well east of the state.

For the middle of the week, thermal trough with h850 temperatures nearing -20C to support below normal temperatures, where wind chills will near or dip down into the single digits (Thursday morning). This will also likely be an active week regarding lake effect snow showers given the cold airmass and will be something to address early next week.

MARINE .

Low pressure moves off to New England tonight but leaves an elevated northwest gradient in its wake while high pressure builds into the western and southern Great Lakes. Gusts to near-gales this afternoon over central Lake Huron will weaken this evening and tonight as the high moves in, and wave action will also weaken and turn more offshore through tonight. The Small Craft Advisory for the nearshore waters around the tip of the Thumb will remain in effect into tonight when waves dissipate below criteria.

The aforementioned high will move to the east coast by early Sunday, allowing a tightened southwesterly gradient to set up over the Great Lakes. The resultant relatively warm flow will lead to stable over- lake conditions which will generally put a cap on the magnitude of wind, put long southwest fetch over the central basin of Lake Huron may lead to gales Sunday morning into Sunday afternoon. A low pressure system will then move through the central Great Lakes on Monday and usher in a fresh northwest wind by Monday night.

HYDROLOGY .

Stationary front and approaching low pressure system is set to develop across Michigan on Monday which will bring the next potential for an extended period of rainfall. Precipitation totals look to range between .25 to .50 inches at this time, with localized higher amount possible depending on the strength of the stationary front and if any training will take place along the front. Precipitation is expected to fall as all rain Monday, with a possible transition to a wintry mix and eventually snow through early Tuesday, before precipitation moves off to the east.

DTX WATCHES/WARNINGS/ADVISORIES. MI . NONE. Lake Huron . Gale Watch from late Saturday night through Sunday afternoon for LHZ362-363.

Lake St Clair . NONE. Michigan waters of Lake Erie . NONE.

AVIATION . CB DISCUSSION . AM MARINE . TF HYDROLOGY . AM

You can obtain your latest National Weather Service forecasts online at www.weather.gov/detroit.

---

Weather Reporting Stations

   EDIT       (on/off)   Help   NOTE: Click on distance to see the station location on a map

Stations	Dist	Age	Wind	Air Temp	Water Temp	Waves	Pressure	DewPt
SBLM4 - Saginaw Bay Light #1, MI	18 mi	59 min	NNW 11 G 15	28°F			1027.1 hPa (+1.4)
GSLM4 - Gravelly Shoals Light MI	35 mi	58 min	W 11 G 14	26°F
TAWM4 - Tawas City, MI	52 mi	79 min	N 2.9 G 5.1	22°F			1027.8 hPa

Wind History for Harbor Beach, MI

(wind in knots)    EDIT      (on/off)   Help

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

7 PM

8 PM

9 PM

10 PM

11 PM

Last 24hr

S6

S9

S8 G11

S6

S6

SW1

W3

NW9 G13

N21

N16

N19 G23

N16 G22

NW7 G10

NW13 G17

NW11 G18

NW11 G16

NW13 G18

W9 G20

NW12 G17

NW7 G12

NW9 G14

NW9 G15

NW11 G15

NW7 G11

1 day ago

W9

W10 G15

W8 G11

NW8 G12

NW6 G9

NW8 G13

NW13 G20

NW15 G23

NW11 G17

NW10 G17

NW10 G17

NW12 G16

NW11 G16

NW9 G12

NW7 G12

W7

W5

SW4

SW2 G5

SW3

S4

S4

S6

S4

2 days ago

W6 G9

SW4 G7

W6 G10

W6 G11

W9

W12 G19

W9 G15

W12 G17

W14 G20

W11 G18

W12 G18

W8 G15

NW8 G12

NW10 G13

NW11 G15

NW12 G17

NW10 G16

NW12 G15

NW11 G16

---

Airport Reports

    EDIT      (on/off)   Help   Click EDIT to display multiple airports. Follow links for more data.

Airport	Dist	Age	Wind kt	Visibility	Sky/Weather	Temp	DewPt	Humidity	Pressure
Saginaw County H W Browne Airport, MI	10 mi	64 min	W 3	10.00 mi	Fair	25°F	17°F	74%	1028.4 hPa
MBS International Airport, MI	11 mi	66 min	W 6	10.00 mi	Fair	23°F	15°F	72%	1029.6 hPa
Jack Barstow Airport, MI	21 mi	64 min	N 0	10.00 mi	Fair	19°F	17°F	93%	1028.4 hPa

Link to 5 minute data for KHYX

Wind History from HYX (wind in knots)

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

7 PM

8 PM

9 PM

10 PM

11 PM

12 AM

1 AM

Last 24hr

S5

S3

SW5

W5

NW8

NW8

NW13 G18

NW12

NW10 G17

NW12 G15

NW10

NW11 G17

NW12

NW13 G20

NW11

NW13 G17

NW13 G17

W9

NW12

W9

NW7

W6

W3

W5

1 day ago

W10 G15

W12

W10 G15

W8

W8

W7

W9

W7

NW9

W8

W9

W7

W7

Calm

W5

SW3

Calm

Calm

SE3

SE3

SE4

SE5

S5

S5

2 days ago

SW8

SW10

W10

W7

SW5

W9

W7

W5

W7

W10

W8 G14

W10

W8

W10

W13 G16

W11

W11

W11

W11

W11 G17

W11

W9

W9

W10

---

Tide / Current Tables for

   EDIT   Weekend mode (on/off)   (on/off)   Help

---

Tide / Current Tables for

   EDIT      (on/off)   Help

---

Weather Map

       (on/off)   Help Weather Map

---

GEOS 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

---

Wind Forecast for Detroit/Pontiac, MI (0,6,7,8)

      (on/off)   Help

---

Ground Weather Radar Station Detroit, MI

   (on/off)   Help

---

Cookie Policy: This webiste uses cookies to save your settings. No personal information is saved. You can disable cookies in your browser if you like but it is not recommended for this site. I do not sell cookies. Go to a bakery for that. In fact I do not sell anything. To disable cookies from L-36.com, please refer to the Help button in your browser. Privacy Policy: I do not sell or share any user data or anything else for that matter. I do not keep site logs longer than I need to to keep bad actors off the site. Basically, I delete them after looking at them. If you are subject to CCPA, Google ads on this site will not be based on your past behavior so you will likely not see an ad for a lawn mower just because you looked for one at a big box website. I do not believe this site is subject to CCPA but I am doing what I can to follow the guidelines anyway. 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.