Area Forecast Discussion
Issued by NWS Milwaukee/Sullivan, WI
Issued by NWS Milwaukee/Sullivan, WI
942 FXUS63 KMKX 260229 AFDMKX Area Forecast Discussion National Weather Service Milwaukee/Sullivan WI 929 PM CDT Tue Mar 25 2025 .KEY MESSAGES... - Increasing chances (50-65%) for showers and possibly some snow Wednesday evening/overnight, lingering into Thursday, primarily for southwest WI but some chances (20-30%) exist further east as well during this time. - March looks to go out like a lion. While temperatures are expected to gradually rise through the work week, a large weekend storm has the potential to bring a prolonged period of rainy weather to cap off the last few days of the month. && .UPDATE... Issued 925 PM CDT Tue Mar 25 2025 Dry air and a more southwestern shift in the axis of the mid- level ripple of vorticity will keep the bulk of the precip out of WI. However, still cannot rule out a isolated shower or two to sneak across the Mississippi River in far southwestern WI. Thus will still maintain low-end PoPs (<25%) for the remainder of the evening. Otherwise, seeing colder lake air push inland and drop temps near and inland from the lakefront quicker than previous forecast. Thus have been chasing this temp trend. Given the mostly clear skies, thinking temps will fall quick with the radiational cooling and light winds. May even need to lower temps a bit more than the current forecast with lows potential dipping down into the mid 20s. Wagner && .SHORT TERM... Issued 255 PM CDT Tue Mar 25 2025 Tonight through Thursday: This evening into the overnight period we expect see some additional PVA on the backside of the upper low slide in with some weak midlevel fgen helping out. With the latest model runs showing some increased moisture in the southwest parts of the CWA we will see increased chances (30-40%) for rain, perhaps with some snow mixing in. CAMs generally show an area of precip but there are some differences among the models primarily as it relates to the location of exactly where we see the showers set up. The HRRR for example largely misses us to the west with several others, including the ARW, NAM, RAP showing these showers pushing through our southwest. Wednesday looks largely quiet during the day with high pressure dominating the region. The next little system expected to push through will be within the high pressure regime with a plume of midlevel moisture sliding in from the west by the evening hours. Some upper level PVA and midlevel WAA with this moisture will allow for some precip across primarily the southwestern parts of the CWA. 700-500mb Fgen may be a factor as well in the southwest parts of the area. A few CAMs (HRRR/RAP) certainly point to some precip chances further north than most of the other models so I tried to account for that potential in PoPs and QPF despite the fact that most short and long term models keep precip primarily limited to the southwestern parts of the CWA. Some snow may mix in with this but no accumulations are expected. Precip will end sometime Thursday morning with dry and mild conditions the rest of the day as high pressure gradually slides out to the east. Kuroski && .LONG TERM... Issued 255 PM CDT Tue Mar 25 2025 Thursday night through Tuesday: Thursday night expect a warm front to gradually lift north into the day Friday gradually increasing chances for showers from the south with the front likely stalling over the CWA somewhere especially given the the lake conditions likely restricting the northward progression of the front. However into the evening it appears models will push the warm front toward central WI likely keeping much of the precip potential to the north and keeping us in the warm side overnight in large part. The warm front looks likely to sag back south into Saturday. If southern WI can get into the warm sector on Saturday, that would lower our precip chances from what is currently in our forecast (and we would also be much warmer). With onshore surface winds off the cold Lake Michigan, it is possible that the warm front would struggle to make it this far north. How this low will track over the weekend still varies greatly between models, so there is a lot of uncertainty in the precip chances, thunderstorm chances, and temperatures in the extended forecast. Cold air will work into southern WI behind the system Sunday night into Monday. There is a chance of snow on the backside of this system Sunday/Sunday night but chances have decreased somewhat with the system potentially clearing out faster than originally expected but there remains uncertainty with this aspect of the system. Early next week looks drier as we look toward high pressure coming in with weak ridging as the dominant upper level feature. Kuroski && .AVIATION... Issued 925 PM CDT Tue Mar 25 2025 VFR conditions will prevail through the period with high pressure working across the region through Wednesday. Winds will be light and variable overnight and remain fairly light into Wednesday as well. May see periods of high clouds overnight and some diurnal cu develop Wednesday during the day. Wagner && .MARINE... Issued 255 PM CDT Tue Mar 25 2025 Broad high pressure will build into the Midwest by Wednesday morning. Northwest winds will diminish overnight across the lake becoming light and variable tonight through Wednesday. Thursday, low pressure will approach the Great Lakes Region from the northern plains. Winds will shift to the southwest to west and be light to moderate. A trough of weak low pressure will extend from a Northern Plains low to Ohio Thursday night. Look for increasing easterly winds into Friday. Friday afternoon the warm front will likely lift north far enough to bring in southwest winds. These southwest winds will be more impactful over land with some potential for Small Craft conditions in the nearshore with limited gale potential. The trough will lift to the center of Lake Michigan Saturday morning and remain fairly stationary through Sunday as low pressure crosses southern WI. Winds will be east to northeast north of this trough/front and southerly south to southeast on the other side. The front will clear southern Lake Michigan by Monday morning with gusty north winds in its wake. Kuroski && .MKX WATCHES/WARNINGS/ADVISORIES... WI...None. LM...None. && $$ Visit us at weather.gov/milwaukee Follow us on Facebook, Twitter, and YouTube at: www.facebook.com/NWSMilwaukee www.twitter.com/NWSMilwaukee www.youtube.com/NWSMilwaukee