Area Forecast Discussion
Issued by NWS Milwaukee/Sullivan, WI
FXUS63 KMKX 221738
Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
1238 PM CDT Wed Mar 22 2017
Cigs on lake effect clouds are gradually rising while the spatial
extent of the clouds is quickly diminishing. Clouds should mostly
clear out in the next few hours. MVFR cigs might hold out for
another hour in MKE, but given the current trends, think either
skies will scatter or cigs will make it above 3kft very soon.
Another round of mid clouds will move in this evening ahead an
approaching low pressure system. Cigs will stay above MVFR for
this period, but will fall once the low gets closer and rain
moves in to the west on Thursday afternoon and across the rest of
the area in the evening.
.PREV DISCUSSION... (Issued 917 AM CDT Wed Mar 22 2017)
High pressure continues to settle over the region. Little to no
change from the previous forecast is needed.
SCA still on track to end at 10am. Winds have fallen well below
20kts, but some 4 foot wave may remain, especially in our southern
Winds and waves will pick up again ahead of a low pressure system
on Thursday, likely prompting another SCA from as early as
Thursday morning, lasting into Thursday night.
PREV DISCUSSION... (Issued 629 AM CDT Wed Mar 22 2017)
AVIATION(12Z TAFS)...LES clouds are returning to se WI for
several hours this morning. Bkn035 stratocumulus expected but
areas of MVFR Cigs are possible. Clearing skies then expected
for the afternoon. Middle to high clouds will increase from
west to east tonight.
PREV DISCUSSION... (Issued 330 AM CDT Wed Mar 22 2017)
Today and Tonight...Forecast confidence high.
Lake effect clouds will likely affect much of far ern WI toward
sunrise as the 1000-850 mb flow veers nely. However, the flow will
weaken by the middle of the day while 850 mb temps warm slightly.
Thus, mostly sunny skies are expected by then. A esely flow will
then prevail for the afternoon with high temps ranging from the
middle 30s over the lake counties to the lower 40s over south
Polar high pressure will track across the nrn Great Lakes into the
lower Great lakes through tonight with the upper ridging over the
High Plains reaching the MS River Valley. Sely flow will respond at
the sfc with lower to middle warm advection ensuing tonight. The
warm, moist advection in the middle levels will result in increasing
cloud cover from west to east tonight but no precipitation.
THURSDAY - Confidence...Medium
Pronounced warm/moist advection in place with southwest 850 millibar
flow. the 850 jet which starts off the day in the Central Plains
leans into the Upper Midwest as the day wears on. Most models show
at least light qpf evolving within this regime throughout the day.
Only the GFS tends to keep the east free of precip with a lingering
dry layer. Will take a blended approach to pops at this point which
suggests a gradual increase in rain potential esp during the
THURSDAY NIGHT THROUGH SUNDAY - Confidence...High
A wet and unsettled period is in store for southern WI. A 500
millibar low will slowly move from the southern Plains towards the
Great LAkes this period. A period of enhanced frontogenetical
forcing is expected across central WI including at least the
northern CWA from Friday afternoon into Saturday evening. Progs show
a qpf max associated with this east/west oriented 850
baroclinicity/moist boundary. The 500 low will open up as it
approaches nrn IL on Sunday with occlusion getting underway with the
surface reflection. This will support keeping clouds/shower chances
into Sunday though there is some suggestion that some of the
steadier rains start shifting off to the east.
MONDAY - Confidence...Medium
A shortwave drops in from the northern stream though precip is
focused more to our north with this feature. Meanwhile another
shortwave shifts from the Plains into the mid Miss Vly with precip
to our south with this. So we may be able to dry out a bit though at
the surface there is an inverted trough axis but any organized lift
looks lacking at this point. Going with Superblend guidance.
TUESDAY - Confidence...Low to Medium
Low level trough proggd to shift east with High pressure building
in. The GFS shows a bit more cold advection behind this system than
AVIATION(06Z TAFS)...Lake clouds moving south and scattering out
from the north. still some MVFR CIGS early this morning. MSN should
be far enough west to avoid most cloud cover.
VFR Wednesday with scattered cumulus mainly east then increasing
high clouds from the west in the afternoon.
MARINE...A Small Craft Advisory is in effect until 10 AM CDT for
brisk northerly winds and high waves. Lessening winds and wave heights
are then expected the remainder of the day.
Another Small Craft Advisory will likely be needed for Thu-Thu nt.
Breezy sly winds and high waves will develop as a warm front
approaches from the south. The highest waves will occur north of
Today/Tonight and Aviation/Marine...Gehring
Thursday THROUGH Tuesday...Collar