Freeze Warning 2, NWS La Crosse, WI

Area Forecast Discussion
National Weather Service La Crosse WI
1220 PM CDT Thu Apr 30 2026

.KEY MESSAGES...

- Cool weather continues through Friday with highs in the 50s
  and lows in the 30s, leading to periods of frost/freeze
  concern during the overnights. Temperatures warm towards
  normal this weekend and into next week.

- Isolated to scattered showers are possible this afternoon and
  again Friday afternoon (10-30%), but overall timing and
  location predictability is low.

&&

.DISCUSSION...
Issued at 1150 PM CDT Wed Apr 29 2026

Cool Temperatures then Warming

Cool temperatures linger today and Friday as an upper level low
churns over the Great Lakes region. Confidence remains high in these
temperatures as very little spread in the 25th-75th percentiles,
on the order of 5 degrees or less, is noted within the majority
of the ensemble suite. During the overnight hours, the cold air
stagnates under clear to mostly clear skies with nearly calm
surface winds. This set up favors frost/freeze conditions, which
are expected through Saturday morning with the current
frost/freeze headlines possibly needing to be expanded into
other counties for the coming nights.

As we head into the weekend, temperatures trend warmer as the upper
low shifts eastward, allowing warmer air to advect into the region.
High temperatures on Saturday reach into the 60s, again with
little variability in the 25th-75th percentiles. A bit more
uncertainty in exact temperatures comes into play as we head
into Sunday and early next week. Looking at the 30.00z
AIFS Ens/AIGEFS, the 25th-75th temperature spread begins to
increase beyond Saturday, upwards of 10-15 degrees. The
important thing to note is that while the exact temperature is
uncertain, the overall warming trend is still depicted despite
the variation.

Showers This Afternoon and Friday

With the bowling ball of a low sitting atop the Great Lakes region
through Friday, sending shortwave trough after shortwave trough into
the Upper Mississippi River Valley within the northwest flow and
cold air advection regime, isolated to scattered shower development
appears reasonable to expect both this afternoon and Friday
afternoon. The primary 500hPa shortwave trough this afternoon shifts
southeastward through the morning hours, sparking some weak surface
cyclogenesis over eastern Iowa and northwestern Illinois this
afternoon that eventually lifts slightly northward into
Wisconsin. Forcing associated with these features combined with
0-3km lapse rates steepening to 7-8C/km per the 30.03z RAP
should provide enough upward motion for some isolated showers
during the afternoon, primarily across Wisconsin where the
forcing will be maximized. A similar set-up occurs for Friday,
albeit without the cyclogenesis, as another shortwave pivots
through the Upper Mississippi River Valley with coverage
expected to be a bit more expansive as compared to today. Those
further north, especially north of I-94, may even see some
snowflakes mix in with the rain during the afternoons. RAP/HRRR
soundings show the mixed layer reaching into the DGZ while
surface temperatures remain near freezing with the possibility
to wet-bulb below freezing. The main limiting factor to
precipitation both days is low level saturation. These same
model soundings depict some dry air below 5kft which may prove
challenging for hydrometeors to fall through, dependent on how
strong the forcing associated with the showers ultimately ends
up being.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 1220 PM CDT Thu Apr 30 2026

VFR conditions through the TAF period. Northwest winds
sustained at 10 to 15 mph through the afternoon, with locations
west of the Mississippi River seeing up to 20 mph. Winds
diminish overnight and then increase to 5 to 10 mph by mid
Friday morning. Scattered rain showers are possible (10 to 25%)
for areas north of I-94 and in far southwest Wisconsin this
afternoon. Light rain chances return tonight and continue into
Friday morning for southeast Minnesota and northeast Iowa. As
the afternoon arrives, the entire region could see scattered
rain showers into the evening. CIGS remain between 5kft and
10kft with coverage between SCT and BKN.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
IA...None.

&&

DISCUSSION...Falkinham
AVIATION...Cecava

Hazardous Weather Outlook
National Weather Service La Crosse WI
756 AM CDT Thu Apr 30 2026

IAZ011-MNZ079-088-096-WIZ017-029-032>034-041>044-053>055-061-
011700-
Allamakee-Wabasha-Winona-Houston-Taylor-Clark-Buffalo-Trempealeau-
Jackson-La Crosse-Monroe-Juneau-Adams-Vernon-Crawford-Richland-
Grant-
756 AM CDT Thu Apr 30 2026

This Hazardous Weather Outlook is for portions of northeast
Iowa...southeast Minnesota...central Wisconsin...north central
Wisconsin...southwest Wisconsin and west central Wisconsin.

.DAY ONE...Today and Tonight

Temperatures tonight will fall to near or below freezing, which
could damage sensitive vegetation.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

Overnight low temperatures will fall to near or below freezing
during the morning hours on Saturday, which could damage sensitive
vegetation.

.SPOTTER INFORMATION STATEMENT...

No action needed.

.EMERGENCY MANAGEMENT COORDINATION...

No webinar is scheduled.

IAZ008>010-018-019-029-030-MNZ086-087-094-095-011700-
Mitchell-Howard-Winneshiek-Floyd-Chickasaw-Fayette-Clayton-Dodge-
Olmsted-Mower-Fillmore-
756 AM CDT Thu Apr 30 2026

This Hazardous Weather Outlook is for portions of north central
Iowa...northeast Iowa and southeast Minnesota.

.DAY ONE...Today and Tonight

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

Overnight low temperatures may fall to near or below freezing
during the morning hours on Saturday, which could damage sensitive
vegetation.

.SPOTTER INFORMATION STATEMENT...

No action needed.

.EMERGENCY MANAGEMENT COORDINATION...

No webinar is scheduled.

KDS