119
FXUS63 KARX 150554
AFDARX

Area Forecast Discussion
National Weather Service La Crosse WI
1254 AM CDT Wed Jul 15 2026

.KEY MESSAGES...

- Hazardous heat continues today with heat indices in the mid
  90s to low 100s.

- Smoke from Canadian and northern Minnesota wildfires will move
  over much of the forecast area today and again on Thursday.

- Rain chances return Thursday afternoon (10 to 15%).

&&

.DISCUSSION...
Issued at 1254 AM CDT Wed Jul 15 2026

Staying Warm Through Late Week:

The anomalous mid-upper level ridge seen degrading and stretching
from the Upper Mississippi to Ohio River Valleys Tuesday night.
Resultant warmest surface temperatures will bifurcate the forecast
area, perpetuating ongoing Heat Advisories with heat indices nearing
100 degrees in these areas.

Wildfire Smoke & Air Quality Impacts:

Increasing forecast concern from near surface wildfire smoke
concentrations through Thursday as northerly winds advect
particulates from Canadian wildfires into the Upper Midwest. Current
forecast confidence for synoptic convergence along the forecast area
keeps gradient of smoke concentrations from southwest to northeast.
Therefore, while Air Quality Alerts have been issued in Wisconsin,
lower confidence in our southwestern peripheral counties of
northeast Iowa may result in lack of Air Quality Alerts there and in
additional counties of southeast Minnesota. Otherwise, have slightly
decreased temperatures through Thursday in collaboration with
neighboring offices due to increased wildfire smoke concentrations
inhibiting incoming shortwave solar radiation.

Precipitation Chances Thursday:

Furthermore, as the north wind sags south, the moisture boundary
suggests some chance for precipitation. While current confidence for
storm initiation remains low to due overall lack of forcing, moist
PWATs (1.25+) with little synoptic progression raises concerns of
heavy rain should storms persist.

&&

.AVIATION /06Z TAFS THROUGH 06Z THURSDAY/...
Issued at 1254 AM CDT Wed Jul 15 2026

Valley fog will be around once again through the early morning
hours. After the fog dissipates, smoke from Canadian and
northern Minnesota wildfires moves in this afternoon and lingers
through the day on Thursday. There is not enough confidence to
put smoke in the TAFs but if confidence grows that this smoke
will lower visibilities enough then smoke will be out in the
TAFs. Light northwest winds this morning transition to light and
variable for the afternoon and evening. There is a low chance
(less than 10%) of showers and storms in portions of western
Wisconsin this afternoon.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
WI...Heat Advisory until 8 PM CDT this evening for WIZ029-032>034-
     041>044-053>055-061.
MN...Heat Advisory until 8 PM CDT this evening for MNZ079-086>088-
     094>096.
IA...Heat Advisory until 8 PM CDT this evening for IAZ010-011-030.

&&

$$

DISCUSSION...JAR
AVIATION...Cecava