Area Forecast Discussion
Issued by NWS Milwaukee/Sullivan, WI
Issued by NWS Milwaukee/Sullivan, WI
817 FXUS63 KMKX 100857 AFDMKX Area Forecast Discussion National Weather Service Milwaukee/Sullivan WI 357 AM CDT Thu Oct 10 2024 .KEY MESSAGES... - The warming trend with dry weather will persist through Friday. - Elevated fire weather conditions are possible Friday, due to warm, dry, and breezy conditions. - Brisk northwest winds and falling temperatures Sunday. A chance (30 to 60 percent) of light rain showers, mainly toward east central WI. - Frost/Freeze potential Monday night and Tuesday night. && .SHORT TERM... Issued 357 AM CDT Thu Oct 10 2024 Today through Friday: High pressure over the region will allow for sunshine and light winds today. Expect temperatures to be slightly warmer than yesterday, in the upper 60s near Lake Michigan and lower 70s inland. Lows tonight will also be similar, ranging from the upper 30s toward central WI to the mid 40s near the IL border, and lower 50s along the lakeshore. Friday will be warm and breezy as a low pressure trough/cold front approaches from the Northern Plains. Southwest winds with gusts around 20 mph are likely during peak afternoon heating, and highs should hit 80 to 83 for most. We will see increasing mid level clouds during the afternoon. Dewpoints will be around 50 during peak daytime mixing, with mixing heights up to 4000 ft and minimum RH values in the 30 to 35 percent range. The temps, winds, and RH point to elevated fire weather conditions Friday afternoon and a Special Weather Statement may be needed. Winds will drop off quickly Friday night and our forecast low temps of the lower to mid 40s north of I-94 may not be cold enough if we decouple and clear out. Cronce && .LONG TERM... Issued 357 AM CDT Thu Oct 10 2024 Saturday through Wednesday: The cold front will stall over northern IL on Saturday. Some models try to produce a little light rain along and north of this stationary front. The chance seems very small and dependent upon how much moisture can get imported/trapped in the low levels of the atmosphere, because will be very dry above 7000 ft. Mid level moisture may arrive later Saturday afternoon into the evening with vorticity advection as forcing, but anything that manages to fall out of the sky will be very light. Clouds will keep lows in check Saturday night with the lower 40s forecast. Another mid level shortwave and weak surface low will track from northern MN to southern Lake Michigan Saturday night into Sunday morning. The shortwave is expected to dig as it rounds the base of the upper trough as that upper low closes off Sunday morning. The associated surface low will deepen over western NY during this time, but the degree of deepening is still uncertain. The previous 00z and 12Z ECMWF solutions preferred a weaker low, but the latest 00z now deepens it more. The GFS has been persistent in creating a stronger low. The strength of this low will determine our winds/gusts in southern WI and over Lake Michigan Sunday afternoon and evening. There is a good chance (20 in Madison, 45 in Milwaukee, and 60 in Sheboygan) for showers behind the front Sunday afternoon and evening, with areas toward east central WI having the highest chance and southwest and south central WI remaining dry. Less than a tenth of an inch is expected, so this would not be a drought buster. We have an extended period of time when eastern WI (mainly the lakeshore counties) have a chance of showers in the forecast. There will not be rain this whole time. Weak shortwaves rotating around the upper low will swing down through WI and Lake Michigan Monday through Tuesday, so spotty showers are possible in this prolonged period of cyclonic flow. The bigger story is how chilly it will be. Sunday night lows will be in the mid to upper 30s, but it will be breezy so frost is less likely. Temperatures will only recover into the lower to mid 50s Monday. Light winds and mostly clear skies will allow for temperatures to drop to around freezing Monday night/Tuesday morning. Frost/freeze headlines will likely be needed. Tuesday and Tuesday night will be a similar story. The upper low will exit by Wednesday and warm air with well above normal temperatures will return to southern WI for the end of the week. Cronce && .AVIATION... Issued 357 AM CDT Thu Oct 10 2024 VFR conditions with another day of light winds is expected today and tonight. Look for increasing southwest winds Friday. Cronce && .MARINE... Issued 357 AM CDT Thu Oct 10 2024 Strong high pressure will linger over the Upper Great Lakes until Friday morning. Winds will become southerly and breezy tonight into early Friday as a low pressure trough approaches. The associated cold front will drop down the long axis of Lake Michigan late Friday afternoon and evening. Winds will abruptly change to northerly behind the cold front and remain breezy into early Saturday morning. Gusts up to 25 kt are likely, as well as high waves, so a Small Craft Advisory will probably be needed. Look for winds to ease and become easterly as weak low pressure crosses central Illinois Saturday. Another low will track from MN to southern Lake Michigan Saturday night, then deepen as it tracks across Lake Erie on Sunday. The degree of deepening is still uncertain. This will result in gusty northerly winds over Lake Michigan Sunday afternoon and night, and there is a chance of low-end gales for the open lake. Cronce && .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