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Area forecast discussion 
National Weather Service La Crosse WI
1130 am CDT Sat Oct 10 2015

Short term...(today and tonight)
issued at 230 am CDT Sat Oct 10 2015

Another pleasant autumn day on tap as heights rise with upper ridge
spreading east.

Surface ridge just southeast of area has kept winds light enough
overnight for areas of fog to form...especially on Wisconsin side
where gradient is weakest. This should clear up relatively quick
this morning.

As lower level flow becomes more southerly today...warm air
advection will begin to increase. Should see temperatures back up
above seasonal normals today and with gradient up tonight...boundary
layer winds should limit extent of fog.

Long term...(sunday through friday)
issued at 230 am CDT Sat Oct 10 2015

Flow across northern tier will be impacted by strong short wave
trough. Response as wave approaches will be seen with southwest flow
and near record warmth on Sunday. See climate section below for
details on records.

As wave passes Sunday night into dynamics and q-g
forcing remain north of area so initial dry airmass and lack of
saturation will likely make for dry frontal passage. Left small rain
threats northeast of Interstate 94 but model trends have certainly
been trending drier. Given strength of wave though...could still see
some higher based sprinkles or thin band of convection.

Main story will likely be strong...Post-frontal winds on Monday.
Given location of short wave...timing of strongest winds and higher
degree of mixing...expect windy conditions that could prompt wind
related advisories...especially in favored open areas to the west.
Dew points could crash during the day as well making for possible
fire weather detailed in fire weather section below.

Cold air advection behind front Monday could level off temperatures
early with more seasonal conditions much of next week.

Quiet northwest flow sets up for much of next week following this
stronger wave. Some indications in European model (ecmwf) that minor short waves
could drop into flow by Thursday and Friday but confidence is low
and given dry pattern...will hold forecast dry for now.


Aviation...(for the 18z tafs through 18z Sunday evening)
issued at 1130 am CDT Sat Oct 10 2015

Winds the main forecast concern for the next couple days. Tight
pressure gradient/daytime mixing will keep winds gusty through the
afternoon-early evening. Gusts should subside with Sundown...and
winds will drop a bit...but not certain there will be full
decoupling/light winds at klse. Regardless...low level jet kicks in
by middle evening...with winds in excess 40 kts by 2 kft. Will continue
low level wind shear mention for klse as a result. More border-line for krst so will
not add to forecast.

Cold front sweeps though Sunday night...and expect a ramp up in wind
speeds as the direction turns northwest. Gusts upwards 40 kts
possible on Monday at krst. Expect a dry frontal passage at this
time...but a period of MVFR ceilings Post the boundary is possible.


Fire through Monday
issued at 230 am CDT Sat Oct 10 2015

Warm and breezy conditions are expected across the region today and
again on Sunday...then strong winds will occur on Monday.

Today...plan on southwest winds of 15 to 20 miles per hour today with gusts
approaching 30 miles per hour at times in open areas. This afternoon minimum
relative humidity values will fall into the lower 40s.

Sunday...breezy southwest wind of 12 to 17 miles per hour are expected with
gusts approaching 25 miles per hour at times. We will see a slight increase in
dew points on this should help mitigate fire weather
concerns with afternoon minimum relative humidity values expected to
fall into the middle 40s. Near record warmth is expected on Sunday when
high temperatures will range from the middle 70s across northern
Wisconsin to the lower 80s over northeast Iowa.

Monday...a cold front pushes through early Monday morning with
strong winds expected in its wake. Look for west/northwest winds to
increase to 22 to 30 miles per hour with gusts approaching 40 miles per hour at times.
Higher gusts cannot be ruled out. Also...a dry slot pushing through
the area will help to not only increase winds but will also bring in
lower dew points for the afternoon with minimum relative humidity
values ranging from the middle 40s across central Wisconsin to the
lower 30s over northeast Iowa. More sunshine and deeper mixing is
expected along and south of the Interstate 94 this
will be the area of most concern for possible grass and crop fire
issues from late Monday morning into Monday afternoon. This will
especially be the case if deeper mixing yields slightly lower dew
points than currently forecast.


issued at 230 am CDT Sat Oct 10 2015

Still on track for record or near record warm up on Sunday.

For October 11th...
lse - record 86 /1928/ normal is 62
rst - record 82 /1934/ normal is 61


Arx watches/warnings/advisories...


Short term...Shea
long term....Shea
fire weather...wetenkamp

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