Expires:No;;216616 FXUS63 KMQT 291952 AFDMQT Area Forecast Discussion National Weather Service Marquette MI 352 PM EDT Fri Sep 29 2023 .SHORT TERM...(Through tonight) Issued at 224 PM EDT FRI SEP 29 2023 Early afternoon water vapor imagery shows broad troughing over western North America with downstream ridging from the Upper Midwest into eastern Canada. Area of showers and embedded thunderstorms developed earlier this morning along the nocturnal low-level jet over central MN is now over NW WI and approaching the far western UP. No electrical activity noted with this complex near the UP, and it is on a weakening trend overall, but some rain may fall over the northwest Superior shoreline counties this afternoon. Elsewhere, skies are partly to mostly sunny over roughly the eastern half of the UP, though there are still fragments of lower clouds streaming northward off Lake Michigan. Over the west half, skies are mostly cloudy due to a combination of low stratocu that has been slow to burn off, and high cirrus canopy associated with the aforementioned area of rain. Raised temps a bit over the east half and lowered over the west half this afternoon to reflect these cloud trends. Tonight, the ridge will shift a bit east, opening the door for weak height falls from the west. Another round of LLJ-fueled convection is expected to develop across central MN, focused especially along and on the cool side of a SW/NE oriented low-level trough. Model consensus indicates this activity moving into the far western UP after 06Z (1 am CDT). HREF mean MUCAPE of 500-1000 J/kg along with 30-40 kt of deep-layer shear supports a small hail threat with any convection that moves into the western UP. This activity should tend to weaken with northeastward extent through the night as it works away from the better forcing, although some leftover showers and isolated storms could make it as far east as western Alger to Dickinson Counties by 12Z (8 am EDT). It should be a rather mild night due to the increasing clouds, southerly flow, and seasonably high moisture content, with lows mainly in the mid-50s to near 60. Lows were bumped up from NBM guidance due to pattern recognition. .LONG TERM...(Saturday through Friday) Issued at 351 PM EDT FRI SEP 29 2023 Key Messages: -Precip chances return over mainly the west and north tonight into Saturday; mostly dry weather returns by Sunday afternoon. -Well above-normal temperatures are expected over the weekend, continuing through the middle of next week. -Weather turns fall-like by the end of next week with increasingly cooler and unsettled/rainy conditions expected. Ridging centered over the Mid Mississippi River Valley builds northward through the weekend becoming amplified over the Midwest and Great Lakes region in response to a mid-level trough digging south over the West Coast and carving out a closed low Saturday night over Nevada. This amplified pattern along with increasing WAA into the Upper Great Lakes will yield summer-like/possibly record temps this weekend into next week. West and north central Upper Michigan have best chances for rain and thunderstorms later tonight into Saturday as a cold front sags southeast toward the area. A more unsettled and much cooler weather pattern is expected for the U.P. later next week as the amplified pattern shifts east and the departing ridge is replaced by the western CONUS trough which will amplify over the Upper Great Lakes by late next week. A shortwave riding northeast along the ridge just north of Lake Superior will push a frontal boundary toward the western and northern side of the U.P. tonight through Saturday before lifting north on Sunday. With convergence along the boundary, HREF ensemble mean MUCAPE up to a few hundred J/Kg (staying below 500 J/Kg), and PWATs approaching 1.3 to 1.7 inches, scattered showers and thunderstorms are expected. Best chances are expected for the west with closer proximity to the boundary, higher available moisture, and convergence; the far south and east may possibly stay dry through Saturday. Despite bulk shear building up to around 30 knots over the north and west Friday night into Saturday, no severe storms are expected. Some heavy downpours late tonight over the far west could bring up to 0.5-0.75 inches of rain. Southerly WAA flow behind the ridge axis brings 850 mb temps up to 15-18C Saturday and 17-19C Monday into Tuesday. The ECMWF EFI has 0.6 to 0.9 over the U.P. for max and min temps starting Saturday with SoT > 0 starting Sunday, both begin to drop off late next week; this signal is also supportive of the expected warming pattern. Daily high and low temps could challenge record high and warm minimum temps with highs this weekend/early next week reaching well into the 70s with possible low to mid 80s over the west half Sunday- Tuesday. Lows are expected in the 50s (except probably lower to mid 60s for downsloping areas near Lake Superior) through the middle of next week. As the amplified pattern begins to shift eastward next week, model guidance comes to a general agreement with a shortwave trough and accompanying cold front moving through the Upper Midwest/Upper Great Lakes later Wednesday into Wednesday night. Look for scattered showers and a few isolated thunderstorms. Despite bulk shear values of 40-50 kts no severe storms are expected as MUCAPE values generally are less than 500 j/kg. CAA behind the front is expected to continue into the weekend as 850 mb temps fall below 0C and perhaps as low as -5C by late next weekend. This CAA along with mid lake water temps of 15C under a persistent cyclonic northwest flow will lead to increasingly blustery conditions along with increased coverage of lake effect/lake enhanced rain showers for the northwest flow favored lake precipitation belts. && .AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon) Issued at 141 PM EDT FRI SEP 29 2023 Stubborn low stratus has finally eroded at SAW/IWD, but continues at CMX at the start of the 18z TAF cycle. Low confidence on erosion timing but best guess is that CMX will follow IWD and scatter out by 19Z. This leaves VFR for the remainder of the day until at least the first half of tonight. An area of rain is approaching IWD and may brush past CMX but is unlikely to impact vsby/cigs this afternoon. Late tonight, another stratus deck is likely to develop at SAW due to moist upslope flow. Cigs likely fall to MVFR after 06Z, with IFR also possible toward 12Z. Elsewhere, a complex of showers and embedded thunderstorms is likely to move into IWD after 06Z. Strengthening low-level winds may also bring LLWS conditions to IWD 00-06Z as well. Forecast has VFR prevailing, but a PROB30 was included for TS to impact cigs/vsby 09-13Z. Remnants of this complex or sct shower development may reach SAW late tonight/early Saturday, but confidence is too low for more than a VCSH mention. At both IWD/CMX, an MVFR deck is expected to develop again in the 12-18Z timeframe. && .MARINE...(For the 4 PM Lake Superior forecast issuance) Issued at 351 PM EDT FRI SEP 29 2023 Expect south-southeast winds across the lake today into tonight to stay below 20 knots. The exception to this would be a brief period this evening over the north-central portion of the lake where some gusts up to 25 knots are expected. A cold front moving into the area late tonight through Saturday will shift winds through the day on Saturday to out of the northeast over western and north central portions of the lake. Winds will gradually veer south by Sunday night, staying below 20 knots. South winds are generally expected to stay below 20 knots through the early part of the week but will probably ramp up to near 30 knots on Wednesday ahead of the next incoming cold front, especially east half. The cold front moving through tonight through Saturday will bring scattered showers and thunderstorms across the lake. Some isolated showers are possible through Sunday morning, otherwise expect mostly dry weather through Tuesday. && .CLIMATE... Issued at 351 PM EDT FRI SEP 29 2023 Record high temperatures at the NWS Office in Negaunee: Sep 30: 80 (2000) Oct. 1: 83 (1976) Oct. 2: 87 (1992) Oct. 3: 78 (2005) Oct. 4: 76 (2007/2011) Record warm low temperatures at the NWS Office in Negaunee: Sep 30: 58 (2002) Oct. 1: 57 (2000) Oct. 2: 60 (2005) Oct. 3: 65 (2005) Oct. 4: 60 (2005) && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... None. Lake Michigan... None. && $$ SHORT TERM...Thompson LONG TERM...Voss AVIATION...Thompson MARINE...Voss CLIMATE...Voss