123 FXUS63 KMQT 010855 AFDMQT Area Forecast Discussion National Weather Service Marquette MI 355 AM EST Mon Feb 1 2021 .SHORT TERM...(This evening through Monday) Issued at 301 PM EST SUN JAN 31 2021 Light snow ended across the west this morning as a stout dry layer moved in from the northeast allowing low level clouds to scatter out. Remaining cloud cover is primarily cirrus and even that has been thinning in places this afternoon. Shortwave ridging is present at 500 mb this afternoon with scattered low level clouds and widespread cirrus. Dry easterly flow is expected to gradually back to north/northwesterly winds overnight, but wind speeds are low so not expecting much low level cloud cover. Decided to go with 10th percentile for lows tonight considering light winds, low dew points, and primarily cirrus cloud cover. Also decided on 90th percentile for highs tomorrow for many of the same reasons. Weak troughing moves over Lake Superior Monday morning with 850 mb temperatures decreasing to around -10C. Given warm lake temperatures, the environment will be marginally supportive of some light lake effect by Monday afternoon for north/northwest wind snow belts. Can't completely rule out some brief periods of freezing drizzle, but decided not to include in the forecast at this time. .LONG TERM...(Tuesday through Sunday) Issued at 354 AM EST MON FEB 1 2021 While the finer details of the longterm still have to be ironed out, the overarching trend seems to be locked in at this point. A pattern change is on its way that will have some second guessing why they asked where the true UP winter has been. As a ridge moves overhead Tuesday into Wednesday, high temperatures will climb 10, and even up to 15, degrees abv normal before the first cold front of a two-act play moves through the UP Thursday night. Widespread synoptic snow looks likely, with maybe some rain mixing in central and west briefly, before a fropa brings in the LES behind it. Late Friday night into Saturday, the second act arrives with the coldest air mass of the season progged to move into the Upper Midwest/Great Lakes region. Model solns as a whole are starting to trend the towards the cooler GFS, which could have daytime high temperatures struggling to break abv zero for parts of western Upper Michigan. As a brief shrtwv passes over the UP Tuesday morning, northerly winds will bring some scattered snow showers along the northerly wind snowbelts. Top of inversion temps are just cold enough around - 12C or so to tap into the DGZ, but there could be some isolated fzdz as well. Accums of snow look minimal, and any fzdz accums looks negligible at this time. These showers come to an end by Tuesday aftn as a ridge builds in from the west and some clearing skies by the evening...best chance central and east. With these clearing skies, trended towards the 25th pctl for lows, which puts some single digits abv zero east and across the colder spots of the western interior. Ridging continues to build in on Wednesday as model 850mb temps climb to just south of the freezing mark. WAA and some stronger winds aloft could bring in the add'l mixing ingredients needed to tap into these warmer temps aloft. Wednesday will be the warmest day of the week, and by the looks of it, maybe the for the next 2-3 weeks. Look for highs in the mid to upper 30s west and low to mid 30s east. Would not be surprised if locations in the Baraga Plains reached 40. The first cold front will approach the UP Thursday morning along a SW to NE axis. A shrtwv will ride along the axis as a sfc low develops. There remains some uncertainty on how fast and deep this sfc low develops, but at this point it looks likely that at least the low will develop and bring synoptic pcpn across the UP. Given the spread, still too early to discuss amts, but seems that at least advy level snowfall amounts should be seen by Friday morning with about half of the EPS/GEFS members pushing warning criteria across the western half of the UP. The west half looks like the past chance for more significant snowfall amts at this pt as they will begin to tap into the lake-enhancement/effect Thursday night. Friday marks the transition to LES across the NW wind snowbelts as the sfc low pulls away to the NW. With CAA and modest pressure rises, could be gusty...which does bring the threat for some pretty chilly windchills. The secondary cold front passes across through the UP Friday night as GFS 850 temps fal...I mean plummet to -35C by Saturday night across western Upper Michigan. While the deterministic EC/GEM aren't quite as cold, it is important to note they have been trending colder for the past few runs. They also aren't that much warmer anyway, both in the mid 20s blo zero with 30 blo temps not too far upstream. EPS spread widens by Sunday morning, but its mean is at -25C, while GEFS mean is a little cooler near - 28C. Regardless, details still have time to be worked out, but the main takeaway is it is going to be cold. While CAA continues to advance, well-mixed BL will bring gusty winds and dangerous wind chills across much of Upper Michigan. Current fcst as wind chills as low as -25F along the WI state line Sunday and Monday morning...and that's playing the middle of the road. LES will continue through the whole weekend, but as colder air advances, accumulations will dwindle as the DGZ crashes, theoretically, blo the sfc. This will lead to the visibility-restricting snowfall, that almost appears as a low stratus cloud consistently falling to the sfc. More details as we get closer, but this weekend looks to be the colder airmass of the season so far, with potentially life-threatening conditions. && .AVIATION...(For the 06Z TAFS through 06Z Monday night) Issued at 1243 AM EST MON FEB 1 2021 Expect northerly winds to bring low-level moisture back into the TAF sites late tonight into Monday. This will result in an MVFR deck at KIWD through the period with conditions lowering to MVFR at KCMX and KSAW Monday morning. There is a slight chance of light snow/flurries at KIWD and KCMX late tonight/early Monday but chance is too low to include in the TAFs. && .MARINE...(For the 4 PM Lake Superior forecast issuance) Issued at 301 PM EST SUN JAN 31 2021 Easterly flow weakens and gradually backs to north/northwesterly overnight as eastern U.S. troughing shifts east. Persistent ridging at the surface support a prolonged period of generally light winds and small waves through Wednesday morning. By Wednesday night, the next storm system will be approaching Lake Superior with increasing winds and waves. Potential exists for much colder weather and heavy freezing spray next weekend. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... None. Lake Michigan... None. && $$ SHORT TERM...EK LONG TERM...JAW AVIATION...JLB MARINE...- JTP