364 FXUS63 KGRB 041932 AFDGRB Area Forecast Discussion National Weather Service Green Bay WI 232 PM CDT Sat Nov 4 2023 Forecast discussion for routine afternoon forecast issuance .SHORT TERM...Tonight and Sunday Issued at 232 PM CDT Sat Nov 4 2023 Main forecast issues center around small chance pops late tonight and slightly better chance pops Sunday afternoon. The 19Z MSAS surface analysis showed a ridge of high pressure that stretched from western IA into central WI. Very weak low pressure was situated over northern Upper MI and the eastern Dakotas. A warm front extended from the Dakotas low through southwest MN. Visible satellite imagery indicated mainly clear skies over most of WI, however a large area of low clouds extended from ND east- southeast into northwest WI. The radar mosaic had picked up a band of light snow or flurries over northern MN. As this ridge of high pressure shifts to our east tonight, a return flow will develop over northeast WI and the resulting push of WAA will bring a quick increase in clouds in the process. Some models (both meso and deterministic) try to spit out very light precipitation over northern WI late this evening/shortly after midnight. Forecast soundings indicate some loss of ice at times, thus there could be a wintry mix of light snow, flurries, drizzle and freezing drizzle across the northwoods. No accumulation of snow or ice are anticipated. Otherwise, clouds will prevent temperatures from falling too far with readings in the upper 20s to around 30 degrees north, lower to middle 30s south. The prevailing southerly wind will continue to pull milder/more moist air mass into the region on Sunday. In addition, models lift the aforementioned warm front into northern WI which should provide enough lift to bring a chance of light rain generally along and north of Hwy 29 Sunday afternoon. Max temperatures on Sunday to be in the middle to upper 40s north, 50 to 55 degree range south. .LONG TERM...Sunday Night Through Saturday Issued at 232 PM CDT Sat Nov 4 2023 A low pressure system tracking through the upper Mississippi Valley Sunday night then the northwestern Great Lakes on Monday. This will bring a warm front through Wisconsin Sunday night with a cold front sweeping through on Monday. Model soundings indicate the column will be fairly warm with this system; therefore, rain is expected as this low tracks through the area. The best chance for rain will be across the north given better moisture and proximity to the upper level dynamics. A tight pressure gradient will result in gusty winds during this period, with gust of 30 to 40 mph expected at times. The rain should end by Monday evening as the low and attendant cold front move off to the east, with some lingering flurries or a sprinkle possible across the far north with some lake effect from Lake Superior. A ridge of high pressure will then keep the area dry through Tuesday. A series of low pressure systems will track through the region from Tuesday night through the end of next week, which will bring the chance for precipitation at times to the area. Some snow may mix in at times, mainly across north-central Wisconsin. However, current indications are that a significant snowfall is not on the horizon for these upcoming events. High pressure should then bring dry weather back to the region to start next weekend. && .AVIATION...for 18Z TAF Issuance Issued at 1234 PM CDT Sat Nov 4 2023 VFR conditions to continue this afternoon through the evening hours as high pressure begins to shift east. Onset of WAA later tonight will bring low-end VFR cigs to most of the region with the exception of the RHI TAF site where MVFR cigs are expected. Southerly winds are forecast on Sunday and this will help to bring milder/more moist air mass into northeast WI. The result will be plenty of clouds of the low-end VFR variety as well as a chance for light rain showers mainly over the northern half of WI Sunday afternoon. && .GRB WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM.....Kallas LONG TERM......Kurimski AVIATION.......Kallas