Scientific Forecaster Discussion
Return to Local Conditions & Forecast
Area forecast discussion
National Weather Service Milwaukee/Sullivan WI
1004 am CDT Friday Apr 18 2014
pesky lower clouds and a northeast wind across the southeast will
keep it rather chilly along the lake...and a tier or two of
counties inland...into the early afternoon. These clouds are
expected to mix out and also move east with time...so increasing
sunshine should help it feel a bit warmer this afternoon. South
central areas will see a decent amount of sunshine...though some
clouds will be increasing to the northwest of Madison.
Overall...other than some changes to sky cover...not much change
to the going dry and rather quiet forecast through tonight.
a mix of MVFR and VFR ceilings around kmke/kenw/kues will linger into
the early afternoon before mixing out and moving off to the east.
These clouds are being enhanced in part by the cool northeast
winds off the lake. Otherwise...look for VFR conditions through
the taf period as high pressure drifts across the area.
Previous discussion... /issued 307 am CDT Friday Apr 18 2014/
Today and tonight..forecast confidence is medium.
Short term models agree with high pressure moving slowly east across
the region today...then to the east tonight. The high will bring
quiet weather. Main issue will be clouds and effects on
temperatures. Low cloud deck over northeast to central Wisconsin has
been lingering and moving slowly to the southeast so far during the
This seems to be following the 500 mb vorticity maximum tracking
east across the region. This may move into northern portions of the
area and linger into the morning hours. Not sure what will occur
with this deck...so kept any clouds to the far northern counties for
Next middle level cloud deck will shift slowly eastward toward and into
the northwestern half of the area later today and tonight. 700 mb
relative humidity fields show this cloud deck fairly well. For
now...kept partly to mostly cloudy skies going for this afternoon
and tonight in the northwest half of the area. The southern portions
of the area are more questionable for these clouds.
Onshore winds will keep areas near the lake much cooler than well
inland today. 925mb temperatures suggest middle to upper 50s well
inland...with 40s Lakeside. Lows tonight should be in the lower to
Saturday - confidence...medium
broad anticyclonic 500 millibar flow shifts a bit to the east
with more of a southwest flow setting up. Low level jet induced precipitation stays
well north. 850 warm air advection will be underway. Surface flow will bring that
cooler lake air into the east. East-southeast winds early transitions more southeast
in the afternoon. 925 temperatures warm to 10-13c which translates to
highs well into the 60s...inland. The east will be appreciably
cooler with the trajectories coming off the lake.
Sunday - confidence...medium
low level convergent zone sets up across central WI...with the
northern County Warning Area having the best chance of rain showers. Portions of the
southeast may end up being dry for much of the day. There are
various solutions with respect to the expected shortwave activity
with the Gem looking the strongest on this feature. Some upper
divergence noted associated with right rear quadrant of upper lakes
Monday - confidence...medium
stronger shortwave approaches from the northwest later in the day
and into the evening. Meanwhile surface/850 lows develop and bring the
focus more into southern WI.
Tuesday and Wednesday - confidence...medium
high pressure will dominate for the most part. The GFS is more
aggressive in bringing warm air advection/moisture advection induced precipitation later
in the day to the western County Warning Area. Meanwhile the European model (ecmwf) holds things
off until Wednesday night.
Thursday - confidence...low
the 00z European model (ecmwf) is quicker on bringing the 850 jet axis and low
level trough towards southern WI by days end. Will maintain thunder in
the grids as better instability likely by then. In fact cips
analogs extends some 50 percent probs into southern WI for a severe report.
Aviation/12z tafs/...VFR conditions are expected today and tonight
across taf sites. High pressure moving through the region today...then
east tonight...will bring quiet weather. Light north winds will become
northeast to east this afternoon...then east to southeast tonight.
MVFR cloud deck should remain north of taf sites through the morning
hours. Scattered to broken middle level clouds should move into Madison
this afternoon and linger tonight. The eastern sites should remain
more scattered with these clouds.
today/tonight and aviation/marine...wood
Saturday through Thursday...collar