


Area Forecast Discussion
Issued by NWS Marquette, MI
Issued by NWS Marquette, MI
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920 FXUS63 KMQT 161949 AFDMQT Area Forecast Discussion National Weather Service Marquette MI Issued by National Weather Service Gaylord MI 349 PM EDT Thu Oct 16 2025 .KEY MESSAGES... - Widespread rain expected tonight/parts of Friday. - Gusty winds in spots tonight/more widespread Friday. - Above normal temperatures Friday. - Some showers to start the weekend...but a rainy/blustery end perhaps? - Lingering rain chances through midweek with plenty of unknowns. && .SHORT TERM /THROUGH FRIDAY/... Issued at 347 PM EDT Thu Oct 16 2025 Pattern Synopsis/Forecast: Large scale pattern shows the Great Lakes sandwiched between upper lows over Atlantic Canada and the central Rockies (the latter being in the southern branch of a split trough over western North America...with short wave ridging in between extending from the eastern Gulf northward into northwest Ontario. Large area of 1.00-1.50 inch precipitable water values in between the upper ridge axis and Rockies trough over much of the mid/upper Mississippi Valley and adjacent northern Plains...resulting in an east-west oriented moisture gradient across the Great Lakes. Low level warm advection developing across Upper Michigan this afternoon with thermal trough displaced well to the east...ribbon of 850mb dew points above 12C also getting pulled northeast along this baroclinic zone...resulting in extensive cloud cover across Wisconsin and spreading across western Upper this afternoon though with minimal precipitation coverage thus far. 1027mb surface high is centered over the upper Lakes this afternoon...strung out area of low pressure from South Dakota back into the high plains of Colorado...warm front extends from the South Dakota low into Iowa/eastern Missouri. Short wave ridge axis will cross Upper Michigan tonight while the South Dakota surface low lifts northeast toward Lake Winnipeg. Warm sector ahead of the surface cyclone spreads across Wisconsin/Upper Michigan Friday...as associated cold front approaches the region by Friday evening. Primary Forecast Concerns: Widespread rain expected tonight/parts of Friday: Broad isentropic ascent and some more focused low level frontogenesis expected to result in an increase in precipitation coverage over the next several hours...and spreading across the Upper Peninsula as the evening progresses. Some weak elevated instability won`t hurt the cause with an increase in low level theta-e...pretty warm aloft with the upper ridge axis so wonder if we would see a deep enough unstable layer to allow for charge separation and thus lightning/ thunder (more of a gee whiz thing at this point). Precipitation may end across far western Upper during the early morning hours...with drying likely pushing east across the forecast area with some dry slotting ahead of the approaching cold front through the morning. Will see some showers develop along the cold front as it approaches western Upper/northwest Wisconsin Friday afternoon...not much in the way of destabilization forecast ahead of the boundary. Gusty winds in spots tonight/more widespread Friday: Southerly boundary layer wind will increase late this afternoon and tonight across Upper Michigan. Some stronger gusts (20+mph) expected in some of the downslope favored areas along the south shore of Lake Superior. Strongest surface gradient arrives Friday (30-40kt 1000mb geostrophic winds) and even with shallow mixing gustiness expected to become more widespread (20-30+mph from the south). Above normal temperatures Friday: The gusty winds and some breaks in the clouds will warm temperatures up across Upper Michigan on Friday...with an east-west temperature gradient expected with highs in the lower-mid 60s east to the lower 70s west (normal highs are in the lower-mid 50s). && .LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/... Issued at 347 PM EDT Thu Oct 16 2025 Days 2-3 (Saturday-Sunday): Cold front slowly crossing the upper Lakes Friday night/Saturday will drag showers across the state...likely ending across the western half of Upper Michigan Saturday but rain chances may linger across the east through the day. Sunday looks infinitely more interesting with a couple of phasing short wave troughs spinning up a new surface low along the cold front over the mid Mississippi Valley...which then wraps up across Michigan. This could result in a rather rainy/blustery day as winds swing around to the northwest and rain wraps around the circulation...especially across the eastern half of Upper Michigan. But how rainy/blustery will depend on the ultimate evolution of this system. Days 4-5 (Monday-Tuesday): Monday looks cooler...could see some lake induced showers but the boundary layer wind direction is somewhat in question at this point. Potential for another cold front passage later Monday into Tuesday will keep the rain threat going. Days 6-7 Outlook (Wednesday-Thursday): A lot more uncertain into the midweek period regarding short wave trough evolution. Doesn`t look particularly cool...in fact 6-10 outlook which covers Wednesday- Sunday is leaning more warm and dry (though the warm/dry part may be more apt for next weekend). && .AVIATION /18Z TAFS THROUGH 18Z FRIDAY/... Issued at 140 PM EDT Thu Oct 16 2025 Initially VFR ceilings at KCMX/KSAW but KIWD already high end MVFR...with the expectation of at least widespread MVFR ceilings and occasional visibility restrictions as precipitation coverage should increase during the late afternoon. Precipitation should continue into the evening at KIWD/KCMX before likely tapering off with ceilings lifting during the early morning hours...while suspect ceilings will drop to IFR at KSAW later tonight. Low level wind shear expected to develop by early evening at all terminals and will likely persist through late Friday morning. && .MARINE... Issued at 347 PM EDT Thu Oct 16 2025 Surface low lifting northeast from South Dakota into Manitoba tonight will push a cold front toward the upper Lakes...along with a strengthening pressure gradient which will increase winds from the south/southeast tonight into Friday. Winds tonight expected to be strongest over central/eastern Lake Superior gusting over 25kts tonight and Friday...as well as on Lake Michigan where long fetch southerly winds expected to push wave heights to 4-8 feet Friday within the northern Lake Michigan nearshore zones. Cold front crossing the upper Lakes Saturday will allow winds to veer more southwesterly and should weaken as the pressure gradient slackens. Frontal wave expected to develop over the mid Mississippi Valley Saturday...and strengthen as it lifts northeast across Michigan Sunday. How strong this low gets is still up in the air...as some of the probabilistic guidance is trying to push gales across eastern Lake Superior on Sunday. At the very least winds are expected to swing around to the northwest as a result of the low passage. Winds then expected to be shifting around for Sunday/Monday as a a surface ridge crosses the upper Lakes Sunday...and then another low/cold front Monday. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... None. Lake Michigan... None. && $$ SHORT TERM...JPB LONG TERM...JPB AVIATION...JPB MARINE...JPB