Scientific Forecaster Discussion
Area forecast discussion
National Weather Service La Crosse WI
221 PM CST Sat Mar 8 2014
Short term...(tonight through Sunday night)
issued at 221 PM CST Sat Mar 8 2014
Main focus in the short term is on temperatures.
Surface map this afternoon has a ridge of high pressure extending
from the Central Plains into the upper Mississippi River valley
region. Despite full early March sunshine...deep snowpack and
northwest winds with weak cold air advection keeping temperatures in
the middle 20s to the lower 30s.
Look for some stratocumulus clouds to drift into areas west of the
Mississippi River this evening...but then expected to move northeast
out of the area by midnight as winds turn southwest with passage of
the high pressure ridge axis. Otherwise...light winds and mostly
clear skies will allow temperatures to dip into the upper single
For Sunday...breezy southwest winds kick in as the high sinks
southeast of the area and low pressure tracks across southern
Canada. This will pull mild downsloped air off the plains and into
the region with highs expected to top off in the upper 30s to the
Warm air advection middle/high clouds Sunday night along with a light
southwest wind continuing will produce fairly mild overnight lows in
the Lower-Middle 30s.
Long term...(monday through saturday)
issued at 221 PM CST Sat Mar 8 2014
After a rather mild start Monday morning...models continue to be in
good agreement in bringing a cold front into the area by late
morning/early afternoon. Before the cold front arrives...looking for
a quick upward rebound in temperatures into the 45-50 degree range
by early afternoon...then slowly cooling through the reminder of the
afternoon as northwest winds increase.
Focus then turns to precipitation chances late Monday night through
Tuesday. There is a growing consistent signal of strong 850-500mb
frontogenesis mainly along/south of I-90. This is due to
increasingly convergent 700-500mb flow as a northern stream trough
phases with a more vigorous southern stream trough. Thermodynamic
profiles show the potential for another wintry mix of
rain/sleet/snow. Based on this increasingly consistent signal...
decided to push probability of precipitation into the likely category. Otherwise...look for
highs on Tuesday in the 35 to 40 degree range. Light snow chances
will linger into Tuesday night as the phased trough pushes through
the region and lows dip into the teens to middle 20s.
A colder day looks to be on tap for Wednesday with northwest flow
aloft. Kept a small snow chance in across central Wisconsin as
models show a weak embedded trough rippling through that area. Highs
Wednesday are expected to top off in the upper 20s to middle 30s.
A return to milder weather is shaping up for
Thursday/Friday/Saturday as middle/upper level ridge builds back into
the area. This also should keep weather systems deflected North/East
of the area for a dry spell as well. Plan on highs rebounding into
the upper 30s to lower 40s on Thursday...well into the 40s on
Friday...then cooling a bit into the middle 30s/lower 40s on Saturday.
Aviation...(for the 18z tafs through 18z Sunday afternoon)
issued at 1149 am CST Sat Mar 8 2014
Skies are clear for the moment...but a 6-7kft broken to overcast deck is
currently over western Minnesota and should move into the region
this afternoon. This cloud deck should thin out and move east into
the early evening hours as a ridge of high pressure drops to the
south of the region. Winds will be light through tonight but then
ramp up tomorrow morning out of the southwest as the next system
moves to the north of the region. Some gusts in the 18-25kt range
will be possible by late morning.