


Area Forecast Discussion
Issued by NWS La Crosse, WI
Issued by NWS La Crosse, WI
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900 FXUS63 KARX 270855 AFDARX Area Forecast Discussion National Weather Service La Crosse WI 355 AM CDT Fri Jun 27 2025 .KEY MESSAGES... - Dry weather expected today with clouds decreasing this afternoon. - Warmer temperatures are expected this weekend. Strong to severe storms are possible Saturday night and Sunday. - Drier conditions expected next week. && .DISCUSSION... Issued at 355 AM CDT Fri Jun 27 2025 Today We finally get some dry weather today as low pressure moves east and allows upper ridging and high pressure to build their way into the upper Midwest. However, low level saturation and low clouds upstream indicate the low clouds over us will linger through the morning hours as said low pressure departs, but begin to clear up in the afternoon. Warmer Temperatures and Strong to Severe Storms this Weekend The brief ridging today continues into Saturday allowing for southerly flow and low level warm air advection. 925hPa temperatures climb to 24-26C over much of the area on Saturday. With very little variation in the location of the 24C isotherm in the 25th-75th percentile spread, there is high confidence in the temperature forecast Saturday where most areas should reach the mid to upper 80s with heat indices in the low 90s. There is less confidence in the temperature forecast on Sunday given the influence of expected convection. Instability builds across the Upper Mississippi River Valley Saturday afternoon under the aforementioned southerly flow. While it`s still a little far away for a solution from the CAMs, global deterministic models depict an MCS developing across Minnesota Saturday and possibly moving into southeastern Minnesota to west-central Wisconsin Saturday night before weakening. Damaging winds would be the primary threat. Instability is then progged to develop across our area again Sunday, with a mean SBCAPE values of 2500+ J/kg noted in the 26.12z LREF. Deep layer shear doesn`t appear to be ideal for more organized convection however, generally only 15-25kts, with the stronger shear lying to our north. Despite this, forcing via a surface boundary moving through the region should be enough for storms to make use of the instability with damaging wind gusts and large hail possible, in agreement with the CSU Machine Learning Probabilities, which highlight a 15-30% probability of these hazards as well as a Slight Risk from the SPC. Drier Next Week With northwest flow expected to return next week, drier air will be ushered into the region, thus favoring drier weather. However, several shortwaves will traverse the mean flow during this timeframe, so despite the drier air in place, bouts of precipitation are still possible, generally a 10-20% chance on any given day. && .AVIATION /06Z TAFS THROUGH 06Z SATURDAY/... Issued at 1233 AM CDT Fri Jun 27 2025 Mostly dry conditions are expected through the TAF period as the main line of storms from today is now fully into central Wisconsin, although some isolated showers are possible along a cold front moving eastward through the upper Mississippi River Valley (generally 20-30%) through about 12z. IFR to LIFR ceilings remain in place overnight into Friday morning, but low ceilings begin to lift and scatter out Friday afternoon. Mist/fog is also possible tonight into the morning hours with visibilities of around 1-3SM based on observations in central Minnesota. Winds will be generally from the south for much of the area ahead of the cold front, becoming northwesterly across the entire area by 14z. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. IA...None. && $$ DISCUSSION...Falkinham AVIATION...Falkinham