Marine Weather and Tide Forecast for Pepin, WI

DISCUSSION
Issued at 230 PM CDT Sat May 30 2026

Current radar imagery shows a band of scattered showers stretching from west-central MN south into southwest MN early this afternoon.
This activity is moving to the northwest, which is a little unusual for this part of the country. We're in a bit of an anomalous upper- level pattern where a negatively-tilted shortwave over the central Rockies transitions to amplified ridging over the Upper Midwest/central Canada. This results in south- southeasterly flow over the Northern Plains. Breaks in the clouds should result in highs reaching the lower 80s for most of the area this afternoon. Additional showers (and a few thunderstorms) will develop from southeastern SD into IA during this afternoon along a mid-level trough and moisture axis. This precip will travel north and stretch from western to southern MN by this evening. Weakening of the activity is expected through this evening with the loss of daytime heating, but CAMs do hint at some rejuvenation overnight across the southern half of MN along the nose of 850 hPa WAA. Scattered showers and thunderstorms are possible (PoPs currently 30-40%) from western to southern MN early Sunday morning before the nighttime LLJ wanes and precip dissipates. Sunday's weather will be very similar to today's, except showers and storms will be favored about 70 miles to the east. Central to southern MN (mainly west of I-35) will have the greatest chance at rain (PoPs of 20-40%).
Not expecting a soaker but the scattered precip could be annoying if you have outdoor afternoon plans. The activity will slowly lift into eastern MN and western WI Sunday evening. But, models are in good agreement of another round of showers and storms forming over western/southwestern MN Sunday night ahead of some mid-level vorticity and thermal ridging. This precip should slowly push east-northeast overnight into Monday morning before stalling and weakening. Though, a rinse and repeat of the weather looks likely Monday with possible rejuvenation of showers and storms across MN during the afternoon.

The aforementioned shortwave over the central Rockies finally lifts north into Canada Tuesday, ending its influence over our area. Ridging will still remain over the Upper Midwest so Tuesday looks really nice with plenty of sun and highs in the lower to mid 80s. Forecast models show the upper-level ridging beginning to break down and shift east mid-next week onward. As this occurs, southwesterly flow will briefly prevail Wednesday into Thursday, warming us up slightly and giving our best chance of area-wide rain. Split, zonal flow will eventually become dominant over the north-central CONUS through the end of the week. This means we should stay warm (highs in the lower 80s)
and have chances for additional rain with any passing weak shortwaves. Though, large model spread exists in timing and placement of these waves such that PoPs are kind of smeared across the region Thursday into next Saturday. More time is needed to resolve these differences and get greater confidence in PoPs.

AVIATION /18Z TAFS THROUGH 18Z SUNDAY/
Issued at 1230 PM CDT Sat May 30 2026

VFR conditions to persist through the 18z TAF period at most of the terminals. Expansive high clouds continue to spread over the region in association with a plume of moisture flowing into the Upper Midwest. Breezy ESE winds will continue to advect low-level dry air this afternoon, which supports a dry picture for most sites. The one exception is at RWF, where radar displays spotty showers west of the terminal. The moisture plume will lift northeast tonight and will bring better chances for rain showers into RWF/MKT Sunday morning. A brief MVFR cig may accompany the showers. Included VCSH mention at AXN/MSP and kept STC/RNH/EAU dry following morning HRRR & RAP forecast sounding trends.

KMSP...No major changes to the 18z TAF as ESE winds and high clouds will be the theme this afternoon into this evening. We did add in a VCSH mention paired with low-VFR cigs (3-4k feet)
to address the chance for an isolated rain shower tomorrow afternoon.

/OUTLOOK FOR KMSP/ MON-TUE...VFR. Wind SE 5-10 kts.
WED...Mainly VFR. Chance P.M. -SHRA/MVFR. Wind S 10G20 kts.
THU...SHRA likely. Chance TSRA/MVFR. Wind SW 10G20 kts.

MPX WATCHES/WARNINGS/ADVISORIES
MN...None.
WI...None.