356 FXUS63 KGRB 171131 AFDGRB Area Forecast Discussion National Weather Service Green Bay WI 631 AM CDT Sun Apr 17 2022 Updated aviation portion for 12Z TAF issuance .SHORT TERM...Today...Tonight...and Monday Issued at 402 AM CDT Sun Apr 17 2022 A ridge of high pressure will keep the area dry today. Meanwhile, out to the west a low pressure system developing across the northern Plains will bring increasing clouds during the afternoon hours. Highs today will be a bit warmer, ranging from the upper 30s near Lake Michigan to the lower to middle 40s inland. The aforementioned low pressure system will track towards the northwestern Great Lakes tonight then across the Michigan UP during the day on Monday. The low will bring a swath of snow from west to east tonight into early Monday morning, followed by scattered to numerous snow showers later Monday morning and into Monday afternoon behind an occluded front. Model soundings indicate that despite temperatures rising to around 40 on Monday; precipitation type should be mainly snow as the precipitation will be convectively induced with the warm air limited to the very lowest portions of the atmosphere. In addition, there will be steep 0-3km lapse rates of 7 to 8 C/km, decent low level frontogenesis, and low level CAPEs around 100 J/kg indicating there could be the potential for snow squalls on Monday if these parameters could come together. Currently the models are a bit offset as these parameters do not overlap; however, they are in very close proximity and some hi-res models do indicate the potential for some linear intense snow showers at times. Snowfall amounts tonight could add up to 1 to 2 inches across the region, with some areas possibly getting as much as 3 inches. Snowfall amounts on Monday are expected to generally be around an inch, with the caveat that any intense convective snow showers could boost amounts higher in some areas. Lows tonight are expected to range from the upper 20s across the north, to the lower 30s across east-central Wisconsin and the lakeshore. Highs on Monday are expected to be in the upper 30s to lower 40s. .LONG TERM...Monday Night Through Saturday Issued at 402 AM CDT Sun Apr 17 2022 Progressive flow is expected through the extended, with another couple of active weather systems crossing the region through the work week into next weekend. Monday night through Tuesday...Precipitation will be on its way out of the region at the beginning of the extended period. Kept pops in place for the early overnight for any wrap around moisture as the low departs before dry conditions return. The quiet period will be fairly short lived as return flow and WAA aloft return by Tuesday afternoon. This will bring a relatively warmer day with highs in the 40s as well as increasing cloud cover. Isentropic upglide could lead to some light early precipitation breaking out across the region as early as Tuesday night, but the better chances will likely be Wednesday. Rest of the forecast...Wednesday will likely see precipitation across the area as the next low pressure system crosses Canada. WAA will likely lead to precipitation development before the trailing cold front comes through the area. Although sounding support some light snow early in the day, warming temps should bring a switch over to rain by Wednesday afternoon and evening. This will be a fairly fast moving system, with dry conditions and dry air moving in behind the cold front overnight into Thursday. QPF could be a bit higher for this system than on Monday, with around a half inch or so of rainfall across the region. Attention then turns to the end of the week as another warm front may bring active weather back again towards the end of the work week and early weekend. Timing and intensity for this system are still uncertain at this time. Temperature wise the ample southerly flow through the period will bring steadily increasing temperatures through the week, with highs possibly touching into the 50s and 60s by next weekend. && .AVIATION...for 12Z TAF Issuance Issued at 631 AM CDT Sun Apr 17 2022 An MVFR of stratocumulus clouds persists across portions of north-central and northeast Wisconsin this morning. This deck should clear as the morning wears on as satellite imagery shows some holes in the deck, which means it is fairly shallow and should mix out in a few hours with some mixing. Otherwise, high pressure will keep the weather dry today as it tracks across the western Great Lakes region. An approaching low pressure system will bring increasing clouds from west to east this afternoon. The low will will eventually bring light snow and worsening conditions throughout tonight to MVFR and eventually IFR as it tracks closer to the region. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....Kurimski LONG TERM......Uhlmann AVIATION.......Kurimski