817 FXUS63 KMQT 311745 AFDMQT Area Forecast Discussion National Weather Service Marquette MI 145 PM EDT Sat Jul 31 2021 .SHORT TERM...(Today and tonight) Issued at 451 AM EDT SAT JUL 31 2021 Primary weather-related concerns will be the thunderstorm potential again occurring later today (after this morning's activity) and the smoke advecting in from the north and west. Ironwood is currently reporting reduced visbys with haze and a bit of smoke was detected at the office. Upstream, Duluth is currently reporting 3sm with smoke, so it is and will be making its way across at least the western half to two-thirds of the U.P. Confidence wanes a bit as the smoke plume advects east given the available HRRR- and RAP-Smoke guidance, but definitely expect hazy skies at a minimum U.P.-wide. Although the forecast for smoke drops off tonight, it is likely that additional mention may be necessary after taking a daytime assessment of where and how strong the plume is. It may linger through the weekend. As for the thunderstorm potential later today, this early round may exit early enough to allow for just enough recovery time for afternoon convection to be worthy of keeping an eye on the radar. Instability is anticipated to be maximized (but not by any large amount) in the south-central, and coinciding with 30 to 40 kts. of 0-6km bulk shear could be just enough to allow for stronger storms, albeit short-lived and likely pulsey/marginal. With moisture also underwhelming yet some indication of somewhat supportive lapse rates, the primary hazard, if it occurs, will likely be wind due to downdraft potential. Note that any upward magnitudes of these parameters and radar watching will become that much more important. Once daytime heating is lost, the "severe" threat diminishes considerably, although some showers and embedded thunder remains possible overnight as the parent trough axis swings through. As for temperatures, they'll top out near normal for late July with widespread 70s expected, and similarly remain near normal for lows tonight, ranging the full spectrum of 50s with a few spots hitting the upper 40s and lower 60s (interior and lakeshores, respectively). .LONG TERM...(Sunday through Friday) Issued at 310 AM EDT SAT JUL 31 2021 The medium range to extended forecast will consist of an active weather pattern over the Great Lakes as several shortwaves while continue to impact the area on the downstream portion of an upper level wave that remains firmly entrenched over the western CONUS. Unfortunately there will not be high levels of rainfall associated with the moisture to impact the area as Upper Michigan continues to be favored for below normal precipitation chances, and slightly above normal temperatures the next 6-10 days as a gradual warming trend takes place. Sunday will see departing rain showers heading toward lower MI as energy associated with the departing shortwave sags south, and a surface high pressure will continue its approach toward the Great Lakes from the northern Plains. CAA advection will assist with clockwise, northerly onshore flow through the day. 850mb temperatures will be on the cool side...6C to 8C, translating to daytime highs in the middle to upper 60s for most areas, with a few locations creeping up to the lower 70s where cloud cover behind the departing rain showers clears out earlier in the day. Mostly sunny conditions can be expected by Sunday afternoon and evening. Upper level ridge begins to build into the west half of Upper Michigan on Monday, and a mid-level low will have a shortwave break off from the energy from the James Bay and Ontario region toward the Great Lakes area from Monday night into Tuesday. There will be a high level of dry air to overcome due to the subsidence associated with the surface high pressure, so the weak energy associated with the shortwave will struggle to become organized with anything more than rain showers. Confidence in convection developing Monday night into Tuesday remains low at this time. The northern stream of jet energy will remain to the north of Upper Michigan from Tuesday to Thursday, as upper level ridging builds over the central CONUS. Shortwaves will continue to propagate along the northwest flow aloft, potentially keeping areas furthest to the east slightly cooler as the waves have weak impulses of CAA associated with them. However, with the upper level ridge axis shifting over to the central CONUS, this will bring warmer temperatures aloft at 850mb for the west half of Upper Michigan Tuesday through the majority of the extended forecast period...translating to above average temperatures at the surface for the west half. This is a favorable pattern for keeping the region dry. Thursday into Friday does have medium/extended guidance trending towards the upper level wave weakening slightly, allowing a shortwave trough to trek south and bring a better chance for showers and thundershower development to the area. Overall, this would support the CPC forecast of above average temperatures/below average precipitation probability favored for Upper Michigan during the extended forecast period. && .AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon) Issued at 144 PM EDT SAT JUL 31 2021 A sfc trough with a secondary cold front lagging behind it will bring a chance for showers and thunderstorms early this evening for CMX and SAW. Confidence is low for thunderstorms at CMX, but latest trends suggest thunderstorms will develop south of SAW. Left both at VCTS for now. Behind the cold front, some MVFR cigs are expected at SAW with some north wind upslope -DZ/-SHRA. There is a chance MVFR cigs move into IWD and CMX as well. With daytime heating tomorrow, cigs should lift into VFR and there could be a diurnal shower at SAW in the aftn. && .MARINE...(For the 4 AM Lake Superior forecast issuance) Issued at 542 AM EDT SAT JUL 31 2021 Expect north winds to pickup tonight with gusts to around 25 knots possible. Up to 20 to 25 knot gusts will linger through much of the day tomorrow, diminishing tomorrow night and generally remaining below 20 knots through much of the week. Thunderstorms early this morning will clear out but another round will arrive later today. Any stronger storm that potentially develops may contain localized gusty winds. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... None. Lake Michigan... None. && $$ SHORT TERM...lg LONG TERM...BW AVIATION...JAW MARINE...lg