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000
FXUS63 KARX 170339
AFDARX

Area Forecast Discussion
National Weather Service La Crosse WI
1039 PM CDT Tue Apr 16 2024

.KEY MESSAGES...

- Severe weather potential continues into early evening. A
  tornado watch remains in effect for parts of northeast Iowa
  and southern Wisconsin.

- Potential for storm total rainfall of 1 to 2" continues. Even
  outside of storms, strong and gusty east winds 35 to 50 mph
  possible through this evening. Northwest gusts 25 to 35 mph
  Wednesday. A wind advisory continues for much of the area into
  the evening.

- Turning colder to end the week. Still have the potential for
  frost and freeze conditions Saturday morning. Some wind is
  expected, temperatures should get as cold as they could.

&&

.DISCUSSION...
Issued at 225 PM CDT Tue Apr 16 2024

Short term:

Latest water vapor satellite imagery shows upper level closed low
over eastern Nebraska. Pieces of energy wrapping around upper level
closed low is producing showers/storms mainly along and west of the
Mississippi River per latest mosaic radar. Ongoing showers/storms
will continue to pivot around the upper level closed low into the
forecast area this evening into tonight. Severe threat with the
storms will begin to diminish early this evening...as instability
diminishes across southern parts of the forecast area. Precipitable
water values of 0.75 of an inch to 1.25 will allow for some of the
showers/storms to produce an inch per hour rates through early this
evening. However...with strong low level flow and
aloft...showers/storms will track quickly over the region. Rainfall
amounts through Wednesday morning will be 1.25 to around 1.50
inches across the forecast area.

Upper level closed low lifts northward over the Upper Great Lakes
region tonight into Wednesday. Showers and a few storms will linger
over much of the forecast area. Colder air advects into the forecast
area on backside of the upper level closed low. Temperatures remain
nearly steady or slowly fall into the lower to middle 50s Wednesday
afternoon.

Extended:

Behind the storm system today, a large area of 500mb low pressure
will push across Manitoba and Ontario.  A shortwave trough with move
through the Plains into the Mid-Mississippi Valley.   Scattered
showers will push through with the precipitation ending before the
much colder air arrived.  Precipitation chances increase as you move
south of I90 toward DBQ and amounts increase as well from dry to a
wetting rain. Cold advection through the day Friday continues into
the weekend. The winds will remain elevated for Saturday morning, so
this should help mitigate temperatures pitting out. Frost/freeze
conditions still look possible for Saturday morning with lows in the
20s to lower 30s with some mid 30s. The GEFS/Canadian/EPS ensembles
show a  30 to 90% probability of 32 degrees or colder by 7am
Saturday. Cooler than normal temperatures are expected for Saturday
with seasonable temperatures forecast into early next week.

&&

.AVIATION /06Z TAFS THROUGH 06Z THURSDAY/...
Issued at 1039 PM CDT Tue Apr 16 2024

A couple of rounds of showers will move east through the TAF
sites through Wednesday morning. There may be even a few
thunderstorms through 17.10z.

Ceilings will become IFR/MVFR late tonight and Wednesday
morning and remain MVFR on Wednesday afternoon. Skies will then
gradually clear on Wednesday evening.

Winds will gradually weaken overnight. The east winds will
shift to the south and then west on Wednesday morning.
Sustained wind speeds will then increase into the 15 to 25 knots
and wind gusts will range from 25 to 35 mph on Wednesday.|

&&

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

&&

$$

DISCUSSION...DTJ/Zapotocny
AVIATION...Boyne