textproduct: La Crosse

KEY MESSAGES

- Critical to near critical fire weather conditions for Saturday due to strong south-southwest winds and low relative humidities.

- Temperatures go on a warming trend this weekend and early next week as highs on Sunday are in the 60s and by Monday are in the 60s and 70s.

- Multiple precipitation chances (30 to 60%) for next week.

DISCUSSION

Issued at 1142 PM CDT Fri Mar 27 2026

Saturday - Monday: Critical Fire Weather Saturday, Warming Through Monday

Surface high pressure currently sits squarely over the Upper Midwest and Northern Plains late this evening, leading to clear skies and decreasing winds. This high pressure will continue to slide south and east of the area with the pressure gradient quickly tightening through the morning tomorrow as a low develops over the North Central Rockies. As winds start to pick up under partly to mostly clear skies, this will allow even drier air aloft to work its way down to the surface (via 28.00 HREF soundings) causing dew points to lower even further with RH values bottoming out between 15-25 percent. The one good thing to note about this event will be the fact that the strongest winds and lowest RHs will not be co-located as the strongest winds will be west of the Mississippi and the lowest RHs should generally be east of the Mississippi in Wisconsin. Even though the lower RHs are expected east of the river, RHs will still be very low across SE Minnesota and NE Iowa. Combined probabilities of RHs less than 25 percent and sustained wind speeds greater than or equal to 20 mph are in the 60-70% range for much of our area west of the Mississippi River which leads to decently high confidence that critical fire weather conditions will be present tomorrow afternoon. As such, have collaborated with the Minnesota and Iowa DNRs and issued a Red Flag Warning that will be in effect from Noon to 7pm Saturday. As winds will be lighter on the Wisconsin side of the river, have issued a Special Weather Statement for Fire Danger across West Central Wisconsin as fuels in this region are slightly more primed to burn. The recent rainfall yesterday across Southwest Wisconsin should prevent widespread burning though low RHs and decent southerly winds could lead to some spotty burning.

Temperatures tomorrow will start to rebound from today's cool temperatures with highs in the mid 40s to low 50s. With the southerly winds expected to continue through the rest of the weekend and into Monday, temperatures will continue on an upward trend with highs Sunday back into the 60s. By Monday, NBM 28.01 probabilities for temperatures at or above 70 degrees are 60-90% for areas outside the Chimney with forecast highs already in the mid 60s to lower 70s.

Tuesday - End of Next Week: Precipitation Chances Return

As the upper high dominating the pattern across much of the southern CONUS right now weakens through the weekend, upper flow will become more zonal across the northern CONUS. A low amplitude shortwave trough will move east into the Upper Midwest by Tuesday with an associated cold front at the surface bringing rain chances with it. As the front moves to the south, rain chances will generally come to an end for the time being with dry conditions expected for the day on Wednesday. This front should largely wipe out the deep moisture across the region, pushing it to our south. While the front will likely stay south of the region, it looks to become more quasi-stationary, providing a better focus for potential rain/convection mid to late week. Where this front stalls will be important because precipitation seems more likely along and north of the front but if it's too far south then our area might not see as much. So this will be a detail we're paying close attention to over the coming days. By late week, winds will once again shift to the south and will allow warm, moist air back into the Upper Mississippi Valley ahead of another, potentially more potent, shortwave trough moving in for the weekend. There's still plenty of questions on the timing and intensity of forcing mechanisms across the region. Moisture will certainly be available Tuesday and then again later in the week but whether the lift and overall pattern will pan out for more widespread rain chances remains to be seen. Both EC and GEFS members have begun to hone in on the Tuesday and Friday into the weekend timeframes for QPF so we will keep a close eye on these going forward.

AVIATION /12Z TAFS THROUGH 12Z SUNDAY/

Issued at 554 AM CDT Sat Mar 28 2026

VFR expected through the 28.12Z TAF period. Mostly light winds at issuance rapidly increase through the morning hours, remaining strong from the southwest through the evening. Strongest winds west of the Mississippi River Valley locally in southeast Minnesota and northeast Iowa with gusts 35+ kts and 25+ kts elsewhere.

FIRE WEATHER

Issued at 648 AM CDT Sat Mar 28 2026

Relative humidities will drop into the 15 to 25 percent this afternoon. In addition sustained southwest winds will range from 15 to 25 mph with gusts up to 40 mph expected west of the Mississippi River and 30 to 35 mph elsewhere. CThe combination of the strongest winds with very dry conditions results in Red Flag Warning in effect this afternoon and early evening in southeast Minnesota and northeast Iowa. Near critical conditions expected elsewhere in western Wisconsin.

Increasing moisture gradually increases daily minimum RHs through the start of the new week, initially in the upper 20s to lower 40s for Sunday. Fair to Good ventilation rates Sunday and Monday increase across the area come Tuesday.

ARX WATCHES/WARNINGS/ADVISORIES

WI...None. MN...Red Flag Warning from noon today to 7 PM CDT this evening for MNZ079-086>088-094>096. IA...Red Flag Warning from noon today to 7 PM CDT this evening for IAZ008>011-018-019-029-030.