FXUS63 KMQT 191137 AFDMQT Area Forecast Discussion National Weather Service Marquette MI 737 AM EDT Tue Aug 19 2025 .KEY MESSAGES... - Remnant drizzle and occasional fog persists today into tonight, especially upslope from Lake Superior. - Dry weather expected Wednesday and Thursday before the next chances of showers and thunderstorms return to the UP Friday. && .SHORT TERM /THROUGH TONIGHT/... Issued at 416 AM EDT Tue Aug 19 2025 GOES-East Nighttime Microphysics RGB imagery shows high, cold cloud cover evacuating to the south and east of the UP this morning though a considerable amount of low, warm cloud cover filling in behind. Morning METAR reports show a similar weather picture across the UP, light fog, drizzle, and low cloud ceilings. Despite the system departing, plenty of remnant moisture remains, as NAEFS humidity plots show surface humidity values over the 90th percentile of climatology for this time of year. Throughout today, synoptic conditions do not change much, with northwest flow at virtually all levels above the boundary layer. With soundings showing dry air aloft struggling to intrude into the lowest ~200mb, a persistence forecast seems to be in order. While the hi-res guidance shows some bands of light rain (likely forced by impulse shortwaves embedded in the NW flow), have elected to go with a more broad-brush approach to the PoPs today, as while a drizzly day (especially in the upslope regions near Lake Superior) is expected, certainty in whether any given location is actually able to have measurable (0.01+ inches) of rainfall in a given hour is low (15-30%). Visibility should improve somewhat throughout the day as the dew point separates at least a little from the ambient temperature, though fog looks to return tonight with little to no reduction in dew points expected. Expect little variation in temperatures today and tonight, with high temperatures today rising to around the 70 degree mark with lows tonight falling to around 60. With high pressure around 1020mb pushing into the Upper Great Lakes late tonight, the drizzle should end UP-wide early Wednesday morning with breaks in cloud cover becoming more common and cloud bases lifting some. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... Issued at 302 PM EDT Mon Aug 18 2025 High pressure remains in place through midweek before ridge-riding shortwaves cause the ridge to receded southwards by Friday. Expect dry weather to persist to at least early Friday. Then, a deeper trough and associated surface low move through Manitoba and Ontario Friday into the weekend. This will bring in our next chances for rain as a cold front sweeps through. Additionally, though a warming trend is expected after through the mid-week, temperatures may turn cooler than average next weekend behind the front. && .AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/... Issued at 732 AM EDT Tue Aug 19 2025 A stagnant and moist airmass has FG and low ceilings impacting the terminals this morning, with airport minimums at IWD and LIFR at SAW and CMX. Modest improvement is expected during the daytime today but ultimately VFR will be relatively short-lived at IWD and unlikely (33 percent or less) at CMX/SAW. FG and low ceilings then return overnight at all sites, though the details of such categories is somewhat uncertain given the model spread in how improvement occurs during the daytime. Expect mainly light winds out of the north (with some northwest and northeast winds mixed in). && .MARINE... Issued at 302 PM EDT Mon Aug 18 2025 Southeast winds of 15-25 kts across most of the lake, strongest north central, continue into this evening. Winds gradually settle below 20 kts through tonight from west to east as the pressure gradient weakens. Winds then back northerly for Tuesday and become variable through the remainder of the week as broad ridging over the region keeps winds mainly below 20 kts. The next shot at widespread 20-30 kt winds arrives this weekend as a low pressure system tracks to the north. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... None. Lake Michigan... None. && $$ SHORT TERM...GS LONG TERM...BW AVIATION...GS MARINE...Jablonski