028 FXUS63 KMKX 270347 AAB AFDMKX Area Forecast Discussion...UPDATED National Weather Service Milwaukee/Sullivan WI 947 PM CST Sun Jan 26 2020 .UPDATE... A subtle cold front aided by a little wave of vorticity may provide just enough lift to produce a strip of light precip that tracks southward through central and southern WI overnight. Saturation into the snow growth zone may come and go, so we will keep the mention of both freezing drizzle and snow with slight chance pops. && .MARINE... Modest northwest winds over northern Lake MI will shift northerly from north to south across the lake through early morning due to the passage of a weak cold front. The modest northerly winds will become light for Mon night through the middle of the week as large high pressure slowly moves eastward across Ontario. && .PREV DISCUSSION... (Issued 534 PM CST Sun Jan 26 2020) UPDATE... No change to the forecast for tonight. AVIATION(00Z TAFS)... Ceilings are just above 1000 ft over northeast WI, so I added a period of higher ceilings in the TAFs this evening. Expect them to drop to IFR once again with a round of possible freezing drizzle overnight. There is not quite enough confidence to add fzdz in the TAFs yet, but I'll be watching that closely this evening as it slides into central WI. Ceilings should rise above 1000 ft by Monday afternoon. PREV DISCUSSION... (Issued 312 PM CST Sun Jan 26 2020) SHORT TERM... Tonight and Monday...Forecast Confidence is high. A shortwave trough over nw IL will track to the Ohio River Valley for late tnt. A brief period of very light snow or freezing drizzle could clip Lafayette and Green County late this afternoon and early evening. A stronger shortwave trough from nrn Lake MI to Lake Huron will move swd through ern Lower MI, then ewd through the lower Great Lakes for tnt. This feature will aid in bringing the cold front currently over Upper MI slowly swd across srn WI and Lake MI late tnt. A low potential for patchy freezing drizzle and very light snow has been be added to the forecast with this frontal passage. Otherwise cloudy skies and little change in temperature will continue. LONG TERM... Monday Night through Tuesday...Forecast Confidence is Medium... This period will be dominated by dry air above 800mb with a very moist profile below that. We will not see much, if any, ice growth given how shallow the moisture will be. With a very weak surface/low level trough pushing through the region this could provide enough forcing to bring freezing drizzle across parts of southern Wisconsin. This potential will continue into the early afternoon before higher pressure pushes in and we dry out in the low levels. No ice accumulation would be expected. Wednesday through Friday...Forecast Confidence is Medium/Low... Drier air will dominate the region, especially in the low levels Wednesday and most of Thursday. There will be an upper level shortwave that likely pushes through Wednesday morning but does not appear likely to produce precipitation at the surface due to the abundant dry air. Uncertainty grows into Thursday night/Friday as another system potentially moves in but models disagree quite a bit on the what will occur in the upper levels to trigger potential for precipitation, but generally the upper levels should be active. However, the dryness in the low levels may again be an issue for this period as well. Saturday and Sunday...Forecast Confidence is Very Low... Fairly high uncertainty for this weekend given the complete lack of similarities in the models for this period. The GFS has a big upper level low digging through the region where the Euro has a weak shortwave pulling through. This generally shows we will need a few more days to get a better idea of what will happen. AVIATION(21Z TAFS)...Cigs will continue to mostly range from 600-1900 feet this afternoon through Monday. Areas of Cigs less than 600 feet and light fog will occur south and west of Madison during this period. There are slight chances for freezing drizzle and very light snow late this evening into Monday morning with the passage of a weak cold front. MARINE...Modest wnwly winds over Lake MI will shift nly from north to south across the lake from late this afternoon through tnt due to the passage of a cold front. The modest nly winds will become light for Mon nt toward the middle of the week as large high pressure slowly moves ewd across Ontario. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...None. LM...None. && $$ Update...Cronce Tonight/Monday and Aviation/Marine...Gehring Monday Night through Sunday...ARK