866
FNUS73 KMQT 181054
FWSMQT

Spot Forecast for USCG Operation...USCG
National Weather Service Marquette MI
654 AM EDT Mon Aug 18 2025

Forecast is based on forecast start time of 0700 EDT on August 18.
If conditions become unrepresentative...contact the National Weather
Service.

.DISCUSSION...

Scattered light rain showers are over western Lake Superior this
morning and will continue to spread out between the Keweenaw
Peninsula and Isle Royale throughout today. By the early afternoon
hours, there will be about 30 percent chances of a few thunderstorms
embedded in the showers. Southeast winds of 10 to 15 knots are
expected throughout today, with wind gusts around 20 knots (most
windy in a corridor between Copper Harbor and Passage Island, less
windy from the Portage Canal to Rock of Ages). Wave heights of 1 to
3 feet are expected from Portage Canal to Rock of Ages, though wave
heights increase to 3 to 5 feet surrounding the northeast half of
Isle Royale. Chances of rain slowly end tonight with the last of the
thunder moving out of the area by 10 PM. Dry weather with lighter
northerly winds and wave heights of 1 to 2 feet then follow for
Tuesday.

.REST OF TODAY...

Sky/weather.........Mostly cloudy (80-90 percent). Showers likely
                    through the day. Chance of thunderstorms in the
                    afternoon.
Chance of pcpn......70 percent.
Temperature.........60 at forecast start...Max 65.
RH..................84 percent at forecast start...Min 79 percent.
Pcpn amount.........0.25 inches.
Surface winds.......Southeast winds 14 to 16 mph.

TIME (EDT)      7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
Sky (%).........71  74  78  83  87  91  94  96  97  98  97
Weather cov.....    SCH CHC CHC LKY LKY LKY LKY LKY LKY LKY
Weather type....    RW  RW  RW  RW  RW  RW  RW  RW  RW  RW
Tstm cov........                            CHC CHC CHC SCH
Chc of pcpn (%).10  20  30  40  60  60  70  70  70  70  70
Temp............60  60  61  62  63  64  64  64  64  64  64
RH..............84  84  83  82  81  79  82  84  86  87  88
Surface wnd dir.SE  SE  SE  SE  SE  SE  SE  SE  SE  SE  SE
Surface wnd spd.15  15  16  16  16  15  15  15  16  16  16
Surface wnd gst.22  22  23  23  23  20  20  20  21  21  21

.TONIGHT...

Sky/weather.........Cloudy (85-95 percent). Showers likely and
                    slight chance of thunderstorms in the evening,
                    then chance of showers overnight.
Chance of pcpn......60 percent.
Temperature.........Min 62.
RH..................Max 100 percent.
Pcpn amount.........0.14 inches.
Surface winds.......Southeast winds 8 to 16 mph.

TIME (EDT)      6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM
Sky (%).........95  93  92  93  95  96  95  93  90  87  83  79
Weather cov.....LKY CHC CHC CHC CHC CHC CHC SCH SCH SCH
Weather type....RW  RW  RW  RW  RW  RW  RW  RW  RW  RW
Tstm cov........SCH SCH SCH SCH SCH
Chc of pcpn (%).60  50  40  40  40  30  30  20  20  20  10  10
Temp............64  64  64  64  64  64  64  64  64  64  64  64
RH..............88  90  90  90  91  91  91  91  92  92  93  93
Surface wnd dir.SE  SE  SE  SE  SE  SE  SE  SE  SE  SE  SE  SE
Surface wnd spd.16  16  16  15  15  15  13  13  13  8   8   8
Surface wnd gst.21  21  21  18  18  18  16  16  16  13  13  13

.TUESDAY...

Sky/weather.........Partly sunny (60-70 percent).
Chance of pcpn......10 percent.
Temperature.........Max 65.
RH..................Min 93 percent.
Pcpn amount.........None.
Surface winds.......North winds 9 to 16 mph.

TIME (EDT)      6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
Sky (%).........74  71  67  70  69  78  76  72  68  61  54  47
Weather cov.....
Weather type....
Tstm cov........
Chc of pcpn (%).10  0   0   0   0   0   0   0   0   0   0   0
Temp............63  63  63  63  63  63  63  63  63  63  62  63
RH..............94  94  100 100 100 100 100 100 100 100 100 100
Surface wnd dir.NE  NE  NE  N   N   N   N   N   N   N   N   N
Surface wnd spd.15  15  15  16  16  16  16  16  16  13  13  13
Surface wnd gst.22  22  22  23  23  23  23  23  23  20  20  20

$$
Forecaster...GS
Requested by...ENS Conner Flora
Type of request...OTHER
.TAG 2520126.0/MQT
.DELDT 08/18/25
.FormatterVersion 2.0.0
.EMAIL conner.w.flora@uscg.mil