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Area forecast discussion
National Weather Service La Crosse WI
252 PM CDT Thu Oct 17 2019

Short term...(this evening through friday)
issued at 251 PM CDT Thu Oct 17 2019

Near seasonable temperatures in the upper 40s to 50s and plenty of
sunshine seen across most of the area this afternoon as surface
ridging remains in control. Some clouds are still present across
central Wisconsin, but should continue to push east through this
evening. Lows tonight are expected to dip down into the mid 30s to
low 40s with some high cirrus clouds moving in overnight ahead of
the next system. Breezy conditions expected on Friday as the
pressure gradient increases. In addition, mixing in the boundary
layer should tap into higher winds around the 900mb level, which
look to bring surface gusts between 30 and 35 mph. If deeper mixing
occurs, slightly higher gusts will be possible, especially in our
wind-prone areas of southeast Minnesota/northeast Iowa. High temperatures
will also be dependent on the depth of the mixing with a warm nose
sitting just above the mixed layer. If deeper mixing occurs, highs
could possibly be a few degrees warmer. As of now keeping highs in
the upper 50s to mid 60s. Clouds will increase later Friday ahead of
next shortwave trough, but otherwise another pleasant mid-October
day expected, albeit breezy.

Long term...(friday night through thursday)
issued at 251 PM CDT Thu Oct 17 2019

The pattern turns a little more active this weekend into next week.
First, a shortwave trough looks to move through north of the area
Friday night into Saturday, which could bring scattered rain showers
to portions of the area along a southward stretching cold
front/boundary. The best chances for rain look to be mainly across
eastern portions of the area from late Friday night into Saturday
morning. Rainfall amounts with this system look to be light,
generally around a few hundreths to maybe a tenth or two of an

A short break looks likely from Saturday night into Sunday with the
next system arriving Sunday night into Monday as a strengthening low
lifts northeast into the upper Midwest. Rain showers and some storms
look possible with this system. The best chance for an isolated
rumble of thunder would be late Sunday night with MUCAPE values
around 500 j/kg with the increase in moisture. Lingering rain
chances may continue into Tuesday as the western portions of the low
move through the area, while other solutions move rain chances out
sooner. Kept small chances for rain on Tuesday as about half of the
gefs members hold onto chances. Thereafter, differences in model
solutions continue for the middle of next week. European model (ecmwf) and GFS are at
least in better agreement that a shortwave trough may move through
the area, bringing another chance of precipitation. About half of
the gefs members indicate this occurring, but there remain vast
differences in timing and location. Temperatures going into next
week look to be slightly below normal, with perhaps an end of the
week cool down.


Aviation...(for the 18z tafs through 18z Friday afternoon)
issued at 1055 am CDT Thu Oct 17 2019

Cigs: generally skc to a few high clouds through Fri afternoon. Look
for increasing clouds from the west Friday night, with a lowering of
the deck overnight/Sat morning. Some MVFR possible/probable.

Weather/vsby: no impacts expected through the period. Increasing threat
for -shra overnight Fri/Sat morning.

Winds: light winds will be on the increase overnight tonight, then
become breezy/gusty by Fri morning as pressure gradient tightens.
South/southeast sustained at 20 with gusts to 30 kts likely at krst.


Arx watches/warnings/advisories...


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