559
FXUS63 KARX 231749
AFDARX

Area Forecast Discussion
National Weather Service La Crosse WI
1249 PM CDT Sun Jun 23 2024

.KEY MESSAGES...

- Showers and thunderstorms return to the forecast Monday night
  and Tuesday, with a conditional risk for severe thunderstorms.
  A Slight Risk (level 2 of 5) for severe weather remains for
  Monday night and for a small portion of our southern counties
  on Tuesday.

- Another brief break for mid-week before additional shower and
  storm chances return late in the period. Details to be refined
  in the coming days.

&&

.DISCUSSION...
Issued at 349 AM CDT Sun Jun 23 2024

Today - Monday:

After a very active couple of days, it looks like we are finally
getting a much quieter end to the weekend. Current satellite water
vapor imagery and RAP progs show a shortwave dropping down from
Canada towards northern Minnesota. This wave is forecast to continue
down and eventually across the Great Lakes through the day. This
along with daytime heating may allow for some isolated showers
(perhaps a storm) to develop this afternoon, especially to the
north. Otherwise, expecting a much drier day for most with highs
mainly in the 70s to low 80s for a few. Surface high pressure slides
across the region Sunday night with drier conditions and increasing
temperatures (80s) into Monday. Take advantage of the next couple of
days as showers and thunderstorm chances make a return to the
forecast.

Monday Night - Tuesday:

An upper level shortwave trough and attendant surface low are
forecast to move eastward across portions of Canada Monday into
Tuesday. The aforementioned surface high pressure passes through on
Monday and southerly flow sets in, with increasing moisture and warm
advection across the area. With this and an increasing low level jet
Monday night, model guidance suggests the potential for showers and
storms to develop. Given the thermodynamic environment guidance
shows quite strong instability building in, which would generally be
supportive of strong to severe storms. However, there still remains
quite a bit of uncertainty revolving around storm coverage and
evolution, with model forecast soundings showing a stout cap in
place. With this the risk for severe weather remains a challenge and
likely conditional with some details still unclear. For now, SPC has
maintained a Slight Risk (level 2 of 5) for severe weather across
northern portions of the forecast area.

As the shortwave trough continues to track across Canada Tuesday, an
associated cold front is forecast to move across the region. This
may become a focus for further showers and thunderstorms to develop
Tuesday. However, how this all evolves will likely depend greatly on
how the Monday night storms evolve. At this time much of the area
remains in a Marginal Risk (1 of 5) for severe weather, with a small
portion of northeastern Iowa and southwestern Wisconsin counties
just within a Slight Risk (2 of 5) for Tuesday.

Mid-week onward:

Behind the early week systems, a bit cooler temperatures (70s to
around 80) and another much needed break in showers and
thunderstorms looks to come for mid-week. However, another
system is forecast to track across the northern Plains bringing
this break to an end. Plenty of variability among ensemble
solutions still exists this far out, so stay tuned as we refine
the details over the coming days.

&&

.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 1248 PM CDT Sun Jun 23 2024

Diurnal cumulus clouds will gradually develop this afternoon and
then dissipate with the loss of heating late this afternoon and
evening.

From late tonight into Monday morning, there will be 4-8K broken
deck of clouds moving east through the area. These clouds are
associated with a warm front moving through the region.

Skies will gradually clear during the mid to late morning
Monday. In addition, with diurnal mixing, the south winds will
increase into the 10 to 20 knot range and the gusts into the 15
to 25 knot range.

&&

.HYDROLOGY...
Issued at 613 AM CDT Sun Jun 23 2024

Heavy rainfall over the previous couple of days has resulted in many
area rivers and streams running high or in flood stage. Flooding
concerns will last well into the week, with the Mississippi
River also continuing to rise. Fortunately, little rainfall is
expected into Monday. However, another round of showers and
thunderstorms will be possible Monday night into Tuesday.
Although some details are uncertain at this time, will need to
monitor for any further potential hydro impacts with these
storms. Please continue to reference the latest flood
statements for additional updates and details.

&&

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

&&

$$

DISCUSSION...EMS
AVIATION...Boyne
HYDROLOGY...EMS