Sunrise 5:51 AM   Sunset 8:19 PM Moonrise 1:26 AM   Moonset 9:37 AM

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LSZ241 Expires:202310060000;;562980 Fzus73 Kmqt 052307 Mwsmqt
marine weather statement national weather service marquette mi 707 pm edt Thu oct 5 2023
lsz240-241-263-060000- 707 pm edt Thu oct 5 2023
.strong Thunderstorms approaching the waters - .
the areas affected include - . Black river to ontonagon mi - . Lake superior from saxon harbor wi to upper entrance to portage canal mi 5nm off shore to the us/canadian border including isle royale national park - . Saxon harbor wi to black river mi - .
at 707 pm edt, doppler radar indicated strong Thunderstorms, capable of producing winds to around 30 knots. These Thunderstorms were located along a line extending from 11 nm east of devils island to near chequamegon bay, moving east at 40 knots.
strong Thunderstorms will remain over mainly open waters.
precautionary/preparedness actions - .
mariners can expect gusty winds to around 30 knots, locally higher waves, and lightning strikes. Boaters should seek safe harbor immediately until these storms pass.
&&
lat - .lon 4667 9043 4717 9010 4719 8952 4680 8956 4678 8976 4663 9001 4656 9034 4656 9044

LSZ200
No data

FXUS63 KMQT 301854 AFDMQT

Area Forecast Discussion National Weather Service Marquette MI 254 PM EDT Tue Apr 30 2024

KEY MESSAGES

- Rain showers and thunderstorms return late tonight.
- Some patchy fog is possible late tonight into Wednesday morning.
- Active pattern continues through next week as a series of low pressure systems track across the U.S. and affect Upper MI. Above precipitation expected, including chance of thunderstorms at times.
- Temperatures won't stray too far from normal, but they will probably be above normal more often than below normal.

SHORT TERM /THROUGH WEDNESDAY/
Issued at 253 PM EDT Tue Apr 30 2024

As a low pressure center continues lifting into northern Ontario the rest of this afternoon, expect cloud cover to slowly improve, with the isolated light rain/drizzle showers ending across the U.P. by early this evening. However, with cool air aloft still hanging around, thinking the highs will be limited to the 50s across most of the area (as some obs are already showing), save for maybe some spots in the south central getting to 60 and the Lake Superior shoreline only getting into the upper 40s. As we move into the overnight hours, expect cloud skies and rain showers to return to the U.P. late. In addition, there is a small chance (10 to 20%) that we could hear some rumbles of thunder (particularly in the south central) as a low pressure lifts from the Upper Mississippi Valley into Lake Superior. Most of the rainfall is looking to fall in the western U.P., with up to half an inch possible over the western counties. Meanwhile over the central and east, up to a quarter and around a tenth of an inch of liquid is expected, respectively. While this isn't looking to be a soaking rainfall, it will help to alleviate the drought conditions over the western U.P., especially since they did not get as much precip as the eastern half of the U.P. over the past few days. In addition, we could see some patchy fog form ahead of the rainfall and return behind it Wednesday morning due to the warm air advection moving over the area. Thus, given the cloud cover and warm air advection, I'm thinking the low temperatures will only get down into the low to mid 40s tonight. As we move into Wednesday, the cold front of the low moves through the U.P. during the morning hours; the patchy fog dissipates behind the cold front Wednesday morning as some breezy west to northwesterly winds move across Upper Michigan. However, with the low's center still sliding its way from Lake Superior to northern Ontario throughout the day, expect mostly cloudy skies to hang around, with some light rain/drizzle showers possibly holding on over the Keweenaw and east until the late afternoon hours. Expect slightly warmer temperatures Wednesday, with most of the increase being seen in the interior eastern half.

LONG TERM /TONIGHT THROUGH MONDAY/
Issued at 517 AM EDT Tue Apr 30 2024

The recent active pattern that has developed across the Lwr 48 will continue thru next week as a series of vigorous waves track off of the N Pacific and then across the U.S. This pattern will be beneficial in easing ongoing drought over western and eastern Upper MI as frequent rainfall events are expected, some potentially mdt to hvy. The latest drought monitor from 4/25 indicated drought conditions in western Upper MI were into the severe category in portions of Gogebic/Ontonagon counties. To the e, moderate drought was indicated from eastern Delta to western Mackinac counties. Given the dry conditions heading into spring, there were also concerns that the spring wildfire season could be active. For now, this pattern of frequent pcpn events will ease those concerns as well.
So, expectation is for above normal pcpn through next week. As for temps, with the progressive nature of the flow and frequent shortwave passages, expect temps fluctuating around normal, likely not straying too far from normal on most days, rather than any prolonged periods of well above or well blo normal temps. Daily temps will probably end up on the warm side of normal more often than the cool side.

Beginning tonight/Wed, the next vigorous shortwave heading out over the Northern Plains today will briefly swing negative tilt as it reaches Upper MI late tonight, leading to a band of vigorous forcing crossing the area. Models are in overall agreement in showing convection organizing over MN this aftn, then moving into WI this evening. Much of the model guidance shows the negatively tilting shortwave supporting sfc low development within the convection.
Track and strength of this feature will have implications for where the heaviest rainfall occurs in Upper MI tonight. Consensus points toward a track to western Lake Superior, suggesting western into n central Upper MI probably has the best chc of seeing the heavier rainfall amounts. Instability for parcels lifted from the top of sfc based inversion wanes as the system moves toward Upper MI, so not anticipating any thunder tonight. Expect shra to reach western Upper MI toward midnight and the eastern fcst area late tonight. Shra shouldn't last more than about 3-5hrs at any location. Given the late night arrival over the e, shra will linger there until about mid morning on Wed. Sfc trof associated with the low moving across the lake won't exit the eastern fcst area until early aftn, so a few more -shra may develop e into early aftn until trof exits. Rainfall amounts should range from about 0.2 to 0.5 inches, but potential is there for some higher amounts up to 0.75 inches across the w. Fcst soundings indicate abundant, mostly shallow moisture following the wave, so westerly flow upslope -dz is possible over the w Tue morning, and low clouds may linger over the e for much of the day under developing flow off of Lake Superior. Would expect the shallow low-level moisture to mix out over western into central Upper MI during the day, but majority of model guidance suggests this won't happen. In fact, a few of the models have rather deep moisture.
There is abundant dry air to bring down as mixed layer builds, but the potential of clouds to linger for quite a while will at least shorten the window for dwpts/RH to tumble. WRF-ARW is the only model aggressively mixing out moisture, but it does often correctly capture this potential. Given that we're less than 2 months from highest sun angle of the year, inclined to partially lean fcst in that direction. Best drying will occur across interior w into s central Upper MI. With the clearing, building mixed layer will tap stronger winds. Westerly winds could gust up to 35-40mph Wed aftn, depending on how high mixing builds. Even if deeper mixing occurs and RH falls under 30pct, wetter fuels from recent rainfall, including the rain tonight, will work to limit fire wx concerns.
Expect high temps to reach well into the 60s s central, ranging down to around 45-50F near Lake Superior where westerly winds are an onshore wind. If clouds linger thru the day, temps will be a good 5-10 degrees lwr.

Sfc high pressure ridge builds over the area Wed night, resulting in a dry, quiet night. Attention then shifts to the next shortwave swinging across the Rockies Wed night and out over the Northern Plains on Thu. In response, sfc warm front will lift n toward Upper MI with a waa/isentropic ascent regime advancing across the Upper Mississippi Valley into Upper MI. Expect shra to spread into w and central Upper MI during the aftn, then continue Thu night. With precipitable water increasing to 200-250pct of normal, decent rainfall should occur. Ensemble probability guidance suggests a 30- 60pct chc of rainfall of at least 0.5 inches and a 10-20pct chc of exceeding 1 inch. Probabilities are highest over s central Upper MI.
Some thunder is possible with potentially several hundred j/kg of cape avbl for parcels lifted from top of sfc based inversion.

With a cold or occluded front passing and exiting sometime btwn late Thu night and early Fri aftn as low pres lifts over northern Ontario, would expect a trend toward dry weather on Fri, continuing thru at least Sat morning. Then, next shortwave will already be approaching by Sat aftn, resulting in the next round of shra spreading w to e Sat aftn/night. This round of shra will be lighter than the previous.

High pres ridge arriving on Sun will support a dry day. Uncertainty in timing shortwaves grows significantly early next week, but that's not a surprise given the time range. Next wave should arrive at some point Mon/Tue, bringing the next chc of shra in the ongoing active pattern.

AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/
Issued at 152 PM EDT Tue Apr 30 2024

As low pressure continues to move into Ontario the rest of today, expect the cigs to progressively improve to VFR by this evening across the TAF sites. However, don't expect the better conditions to last all that long as a second low pressure system lifts from the Upper Mississippi Valley into Lake Superior late tonight. This brings showers and a low chance (10 to 20%) of thunder across the area after midnight tonight into Wednesday morning. This will tank cigs LIFR conditions across the TAF sites late tonight/early Wednesday morning, although some low-level cloud cover is looking to set up in the north central U.P. near KSAW before the rainfall arrives. Thus, there may be some patchy fog or low-level stratus near KSAW late tonight before the rainfall. As the warm front of the low moves through late tonight, we could see some marginal LLWS across the terminals (around 50% chance). While KIWD was the only one with the LLWS mentioned, each of the TAF sites could see the marginal LLWS; the LLWS will largely be dependent on how much of the higher winds aloft mix down to the surface and the direction of the winds between the sfc and 2 kft aloft. The LLWS threat ends Wednesday morning as the cold front pushes through the U.P. from west to east and brings breezy westerly winds (and gusts) to the sfc. Ahead of the cold front, we could see some patches of drizzle/light rain and fog; once we get behind the front, expect the conditions to slowly improve.

MARINE
Issued at 517 AM EDT Tue Apr 30 2024

Weakening low pres currently just nw of the Keweenaw will exit to the ene today, followed by a weak sfc high pres ridge building over the area by evening. As the low tracks ene and off of the lake, westerly winds on the s side of the low may gust up to 25kt e of the Keweenaw later this morning into early aftn. Otherwise, expect winds mostly under 20kt today, diminishing this aftn to under 15kt by evening. E to SE winds then increase up to around 25kt tonight as the next low pres trof approaches from the w. A low pres will spin up on this trof, and the low is likely to pass over western Lake Superior Wed morning and then exit eastern Lake Superior near Michipicoten Island mid to late aftn on Wed. Marine interests will need to monitor upcoming forecasts closely as there is the potential for this low to intensify sufficiently for gales to occur with shorter notification than desired. This would include the potential of a short period of NE gales to 35kt over western Lake Superior late tonight/early Wed. Of more concern is the westerly winds that strengthen on the s side of the low as it moves toward Michipicoten Island on Wed. Trends from a few models are suggesting potential of a 3-6hr period of 35-40kt gales from just e of the Keweenaw due e across the lake during Wed aftn. Internal probabilistic guidance even indicates about a 20pct chc that high end gales will be achieved. After this period of stronger winds, high pres ridge arrives Wed night, resulting in a quick drop of winds to under 20kt across the lake. These lighter winds will linger across eastern Lake Superior on Thu. Over western Lake Superior, ne winds will be on the increase again on Thu as the next low pres moves out over the central Plains. Expect NE winds to 30kt by late Thu aftn over western Lake Superior. E to SE winds will increase to 30kt over eastern Lake Superior Thu night. There is a 25-40pct chc that low end gale gusts could occur. As low pres lifts into northern Ontario and Fri, winds will shift s to sw. While gusts up to 30kt will continue over western Lake Superior, winds will fall off to under 20kt over the eastern lake. Over the weekend, expect winds mostly under 20kt across the lake.

MQT WATCHES/WARNINGS/ADVISORIES
Upper Michigan...
None.
Lake Superior...
Small Craft Advisory from 7 AM EDT /6 AM CDT/ to 3 PM EDT /2 PM CDT/ Wednesday for LSZ240.

Small Craft Advisory from 7 AM EDT /6 AM CDT/ to 8 PM EDT /7 PM CDT/ Wednesday for LSZ241-242.

Small Craft Advisory from 2 AM to 11 PM EDT Wednesday for LSZ243-244.

Small Craft Advisory from 5 AM to 8 PM EDT Wednesday for LSZ245-246.

Small Craft Advisory from noon to 8 PM EDT Wednesday for LSZ247-248.

Small Craft Advisory from 5 PM to 11 PM EDT Wednesday for LSZ249.

Small Craft Advisory from 3 PM Wednesday to 5 AM EDT Thursday for LSZ250-251.

Lake Michigan...
None.

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