textproduct: La Crosse

KEY MESSAGES

- Temperatures gradually warming from Saturday through Monday.

- Heat Advisories will be likely needed for Monday and Tuesday during the afternoon and evening. Might even need an Extreme Heat Warning on Monday in some locations.

- Maybe some periodic severe weather from Monday night into Wednesday.

DISCUSSION

Issued at 1236 AM CDT Thu Jun 25 2026

Today through Friday night

The models remain in good agreement that there will be zonal flow across the eastern two-thirds of the CONUS from today through Friday. A stationary front will remain in place from the Mid- Mississippi River Valley east into the Mid-Atlantic Region. This front will be the focus for showers and storms. Meanwhile, north to east winds around a high pressure area over Lake Superior will keep the area mainly dry. If there is any showers and storms, they would occur north of Interstate 94 this afternoon and early evening. They would be the result of cold air aloft. High temperatures will be in the lower and mid-70s on Thursday, and in the mid- to upper 70s on Friday. Low temperatures tonight and Friday night will be in the 50s.

Saturday through Monday

The models remain in good agreement that a longwave trough will gradually deepen from Saturday into Monday over the western CONUS. There is still some uncertainty on the placement and how deep it will ultimately become. As this occurs, a 500 mb longwave ridge will build northward from the western and central Gulf northward to Hudson Bay. From Saturday night into Sunday, a warm front will provide a chance of showers and storms as it moves east and northeast through the Upper Mississippi River Valley.

High temperatures will gradually warm during this time period. They will be around 80 on Saturday, in the 80s on Sunday, and range from the upper 80s to mid-90s on Monday. With dew points climbing into the lower and mid-70s, heat indices will likely range from the mid- 95 to 105. There may be even a few locations as high as 110. Wet- bulb globe temperature will be in the mid-80s. As a result, it is looking likely that we might have to issue a Heat Advisory or Excessive Heat Warning for at least Monday.

Monday night and Wednesday

The models are in good agreement that as a series of shortwaves eject out of the western longwave trough from Monday night through Wednesday, the upper level ridge will gradually flatten. These shortwaves will be close enough that they will provide a chance for periodic showers and storms. With strong and and very strong instability across the region, some of these storms could become severe.

High temperatures will range from the upper 80s to mid-90s on Tuesday and depending on the convection and where the upper level high is located temperatures may be either the same as Tuesday or slightly cooler Wednesday. Heat indices will likely range from 95 to 105 on Tuesday. In addition, the wet globe temperature will be in the mid-80s. As a result, we will likely will have to issue another Heat Advisory. If Wednesday remains similar to Monday and Tuesday, an Excessive Heat Warning may be needed to due longevity of this heat.

AVIATION /12Z TAFS THROUGH 12Z FRIDAY/

Issued at 548 AM CDT Thu Jun 25 2026

IFR stratus deck is present this morning along and north of a MSP-EAU line. This will drift south and make a run at RST/LSE but current thinking is that it will break up as the sun asserts itself over the next couple hours. Following this, cumulus in the 2-4 kft range is expected late this morning into this afternoon and have included SCT groups to cover this - cannot rule out occasional BKN ceilings. This afternoon brings a small (15-20%) chance for TS east of the Mississippi, too low for a mention at LSE.

CLIMATE

Issued at 1236 AM CDT Thu Jun 25 2026

With 850 mb temperatures 2 to 3 standard deviations warmer than normal, there will be a potential for some warm low temperature records to be tied south of Interstate 94 on Monday.

ARX WATCHES/WARNINGS/ADVISORIES

WI...None. MN...None. IA...None.