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Area forecast discussion 
National Weather Service La Crosse WI
1145 PM CDT Sat Apr 25 2015

Short term...(this evening through tuesday)
issued at 223 PM CDT Sat Apr 25 2015

Very quiet period upcoming with warming trend and abundant
sunshine.

Current GOES water vapor showing the main players of todays
weather well...with the southern jet stream...closed low centered
near Kansas City MO...and a northern stream shortwave dropping
south into the Great Lakes /with nice subsident signal/. The
deformation between these streams was found across southern WI
with showers early this afternoon...and now is shifting south.
Major rain dissipation has occurred over Iowa in the past hours
per regional radars.

Some upper teens to lower 20s dewpoints are found across northern
and central WI and into The Arrowhead of Minnesota associated with a northwest-
southeast oriented dry air region of 15-20c dewpoint depressions /per
kgrb 12z radiosonde observation/ in the surface-850 mb layer.

Over the next several hours...the northern stream wave will become
dominant over the forecast area and drying will continue to occur
from the N-NE. This will signal the beginning of a clear and
tranquil period of ridge influence. Biggest concern through
Tuesday morning is the dewpoints and dry air influx from the north-NE
for possibly enhanced fire dangers /see fire weather section/.
Otherwise...temperatures will warm a few degrees each day through
Tuesday.

The model suite of solutions does converge on a shortwave trough
moving into the area later on Tuesday. The 25.12z European model (ecmwf) is the
deepest with the northwest flow wave and does produce a bit of
rain shower activity...with the dynamics a direct hit on the
forecast area. It is the most aggressive solution. Have kept a
small rain chance in northcentral WI for this system. A minor
weather system it appears.

Long term...(tuesday night through saturday)
issued at 220 PM CDT Sat Apr 25 2015

No impact weather. Major long wave ridge building through the
period will continue with mainly dry and above normal temperatures.

&&

Aviation...(for the 06z tafs through 06z Sunday night)
issued at 1145 PM CDT Sat Apr 25 2015

High pressure over wester Ontario will provide VFR conditions
through the period.

&&

Fire weather...
issued at 220 PM CDT Sat Apr 25 2015

Ridge building will dominate the the period from tonight through
Tuesday. A north to northeast flow is forecast through the period
with 20ft winds in the 10kt or less range. Will have to keep an
eye on min relative humidities. This forecast update will include
a drop to the daytime dewpoints through Tuesday....which decrease min
relative humidity values as well /about 10 percent/. Difficult forecast however
as soil has moisture from recent rains...and that will provide a
flux of water vapor into the air to battle the dry air in place.
Would think min relative humidity values will at least be in the 20s.
Overall...do not expect elevated fire weather conditions through
at least Tuesday.

&&

Arx watches/warnings/advisories...
WI...none.
Minnesota...none.
Iowa...none.
&&

$$

Short term...baumgardt
long term...baumgardt
aviation...boyne
fire weather...baumgardt

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