927 FXUS63 KAPX 220127 AFDAPX Area Forecast Discussion National Weather Service Gaylord MI 927 PM EDT Wed Aug 21 2019 .UPDATE... Issued at 927 PM EDT Wed Aug 21 2019 Evening composite analysis reveals a fairly deep mid level low over eastern Ontario with suppressed heights sagging into the Great Lakes. A couple short-waves are rotating around the parent trough. One traversing Lake Superior and a second more substantial wave/trough dropping into northern Minnesota that will move through the region on Thursday. At the surface, departing low pressure is over southern Quebec with the front that passed through our area earlier now sliding out of southern Lower Michigan into Ohio. High pressure is building in from the west pulling cooler and substantially drier air into the region (dewpoints have dipped into the 40s across the northern counties). Showers and a few storms in our SE counties this afternoon are long gone. There is another push of cloud cover pressing down through northern Michigan with the cooler air that managed to produce some very spotty showers/sprinkles earlier in the evening. Some thicker high cloud cover is also streaming across the southern part of the forecast area. Rest of tonight: Skies are clear across eastern Upper MI and expected to stay that way. South of the bride, remaining cloud cover should gradually diminish/sink southward through the night with most of northern Lower Michigan eventually becoming clear or mostly clear. Along with diminishing winds/lowering dewpoints, quite a few locations will dip into the 40s by early Thursday morning...low 40s in some spots. && .NEAR TERM...(Through Tonight) Issued at 238 PM EDT Wed Aug 21 2019 ...Much cooler and drier air moving in... High Impact Weather...None is expected. Primary Forecast Concerns...Thunder chances. The surface cold front continues to slowly trudge across northern lower Michigan at this hour. A few showers developed along/just ahead of this front across portions of northern lower earlier this afternoon, even a thunderstorm near Oscoda. Just a few remaining blips on radar across northeast lower which could linger over the next couple of hours. Otherwise, drier air should put any remaining showers to bed later this afternoon with waning instability and lack of heating diminishing the cumulus field as well. A moisture starved short wave then moves through late tonight with little to no affect on the region with the exception of advecting in even drier/cooler air. Lows tonight ranging from the cool mid 40s to lower 50s. && .SHORT TERM...(Thursday through Saturday) Issued at 238 PM EDT Wed Aug 21 2019 High Impact Weather: Minimal A trough will continue to move across the northeast CONUS/Quebec as a jet max rounds its axis while an amplified ridge trails, stretching from the northern Great Plains up into Hudson Bay. A surface cyclone is expected to continue its progression NE across Quebec and deepen slightly as it maintains healthy placement underneath upper-level divergence before becoming mostly vertically stacked and getting choked off from favorable temperature and vorticity advection. As this cyclone progresses, an attendant cold front sweeps across much of New England into the Mississippi Valley during the forecast period. Strong surface high pressure builds underneath subsidence at the upper-level ridge/trough inflection point in Ontario. Amplified flow provided between the aforementioned surface features behind the cold front will spread cooler, dryer air southward into the forecast area heading into the weekend. This continued CAA will bring a taste of fall to many, keeping high temps in the upper- 60s/low-70s across northern Michigan Thursday and Friday. Low temps those nights will also be chilly, dropping into the lower-40s and perhaps upper-30s locally with weak surface winds and clear skies expected overnight. As for precip, a very small chance exists Thursday across NW lower Mi. Mostly NW flow in the low to mid-levels will come across Lakes Superior and Michigan with potential marginal instability as suggested by model forecast soundings. Specifically, 850mb temps near 5C overtop of lake temps near 20C creates delta Ts of about 15C, allowing for parcels lifted from the lake surface to contain non-zero CAPE. This could be enough to spark a few showers across the area. Otherwise, partly cloudy skies are expected Thursday and Friday before clearing up on Saturday. The cooler, dryer airmass in place with subsidence overhead should inhibit rain chances from Thursday night into the weekend. .LONG TERM...(Saturday night through Wednesday) Issued at 238 PM EDT Wed Aug 21 2019 High Impact Weather: Rain/storm chances early next week An amplified ridge is expected to be centered from the Great Lakes up to James Bay at the start of the forecast period as surface high pressure encompasses much of the eastern CONUS and Canada. A trough approaches from the west along the international border with a cyclone expected to form/deepen in south-central Canada as a result of favorable upper-level support and potential transport of warm, moist are poleward. The evolution/timing of this feature is the main focus for the long term forecast. Model guidance hints at a cold front passage in association with this cyclone early next week. While this system does provide the next main chance for rain and possibly a few thunderstorms, considerable uncertainty still exists in regards to favorable shear, instability, and timing to comment on specific thunder/severe chances. Regardless, temperatures are expected to warm back up into the upper-70s and low-80s, which would be slightly above average for this time of year across northern Michigan. && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) Issued at 751 PM EDT Wed Aug 21 2019 Main surface cold front has cleared northern Lower Michigan with northwest flow and cooler/drier air making inroads into the region. There is a secondary push of moisture/VFR cloud cover sliding down through the region this evening along with very spotty sprinkles. But VFR should dominate through tonight. Ongoing northwest gustiness will slowly diminish as we go through the night. On Thursday, Secondary piece of short-wave energy will rotate down through northern Michigan. Along with ongoing cold advection and daytime heating, expect sct-bkn VFR cloud cover to develop across the region through the day. Some northwest wind gustiness will also return. && .MARINE... Issued at 238 PM EDT Wed Aug 21 2019 Winds will continue to gradually pick up from the northwest this afternoon...and will be gusty especially on Whitefish Bay/St. Mary's River and northern Lake Huron nearshore zones where Small Craft Advisories are in effect for later today and tonight. Somewhat gusty winds Thursday afternoon with gusts to between 15 and 20 knots but no headlines will be issued just yet. && .APX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LH...SMALL CRAFT ADVISORY until 8 AM EDT Thursday for LHZ346>348. LM...NONE. LS...SMALL CRAFT ADVISORY until 8 AM EDT Thursday for LSZ321-322. && $$ UPDATE...BA NEAR TERM...AS SHORT TERM...MR/DJC LONG TERM...MR/DJC AVIATION...BA MARINE...AS