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Area forecast discussion 
National Weather Service La Crosse WI
608 PM CDT Thursday Jul 30 2015

Short term...(this evening through friday)
issued at 249 PM CDT Thursday Jul 30 2015

Main forecast concerns are on shower and thunderstorm chances
Saturday night through Sunday night.

Currently watching a weak shortwave trough moving southeast across
northern Wisconsin/Upper Michigan. A cumulus field and isolated
showers and thunderstorms have develop across northern Wisconsin
and Upper Michigan as the shortwave draws closer and provides the
support for this activity. An isolated shower or storm may impact
Taylor County this afternoon. Otherwise...high pressure will
continue to dominate the weather pattern providing dry and mild
conditions. Another weak shortwave looks to move through northern
Wisconsin/Upper Michigan tonight into early Friday morning but is
expected to stay north of the forecast area with dry and quiet
weather persisting. Northwest flow aloft will continue across the
forecast area on Friday with mainly dry and quiet weather
expected. The pressure gradient...between high pressure over the
central /northern plains...and low pressure over Hudson
Bay...will keep the region in a modest pressure gradient on Friday
with northwest winds of 12 to 17 miles per hour expected with gusts of 25 to
30 miles per hour possible during peak heating. Quiet weather will continue
into Friday night as the high remains in control.

Long term...(friday night through thursday)
issued at 249 PM CDT Thursday Jul 30 2015

Low level moisture will try to make a return into the forecast area
on Saturday as low pressure and a weak shortwave approaches from the
northern plains. The nam12 is suggesting dewpoints could climb into
the middle to upper 60s along and west of the Mississippi River...with
some lower to middle 70s dewpoints possible over portions of Iowa. This
seem a little aggressive. The GFS seems more realistic with
dewpoints in the low to middle 60s mainly across northeast Iowa. It
appears the best support for showers and storms will mainly be along
and south of Interstate 90. Shear is not very impressive Saturday
afternoon into Saturday evening across these areas with 0-3 km bulk
shear values of 20 to 25 kts...with stronger shear displaced to the
north of the best cape. 0-1 km MUCAPE values look to climb into the
1300 to 2500 j/k range Saturday afternoon. Cannot rule out an
isolated strong to severe storm from Saturday afternoon into
Saturday evening ... across portions of northeast Iowa. A
cold front and upper trough then slide into the region Sunday
night bringing chances for showers and storms to the region. The
trough then settles over the western Great Lakes for early next
week providing cooler temperatures across the region. Highs on
Tuesday will mainly be in the lower to middle 70s...with lower 70s
expected on Wednesday.


Aviation...(for the 00z tafs through 00z Friday evening)
issued at 608 PM CDT Thursday Jul 30 2015

Another period of VFR weather will occur as high pressure remains
centered over Missouri through Friday afternoon. The winds will
drop under 10 knots by or shortly after 00z this evening. Once the
low level inversion mixes out should once again see gusts at both
taf sites in the 20 to 25 knot range from late Friday morning
through the afternoon.


Arx watches/warnings/advisories...


Short term...wetenkamp
long term...wetenkamp

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