Area Forecast Discussion
Issued by NWS Milwaukee/Sullivan, WI

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
322
FXUS63 KMKX 202324
AFDMKX

Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
524 PM CST Tue Feb 20 2018

.UPDATE...

Rain continues for just a small portion of the far southeastern
forecast area. This precipitation should linger for a few more
hours, before finally ending. Colder air is building in from the
west, and temperatures will rapidly fall this evening as a much
colder airmass builds into the area. In general, the precipitation
should end before temperatures reach the freezing mark, but a few
snowflakes aren`t out of the question later this evening over
Racine and Kenosha counties.

Elsewhere, the falling temperatures may start to lead to some
slick spots given the amount of water that is around. This will
especially be likely as temperatures fall into the 20s later this
evening.

Finally, flooding remains a significant concern over the southern
portion of the forecast area, particularly for those counties
along the Illinois state line. Areal flood warnings and numerous
river flood warnings continue.

&&

.AVIATION(00Z TAFS)...

IFR to low end MVFR will continue for a few more hours, with a
slow improvement through the evening as drier air builds in from
the west. Temperatures will rapidly fall this evening as well,
which could lead to some icing on airfield surfaces where any
standing water remains. Winds this evening will be westerly,
becoming northwesterly overnight into tomorrow morning.

Expect ceilings to finally scatter out to VFR tomorrow morning,
with a cold but otherwise generally sunny day.

&&

.PREV DISCUSSION... (Issued 331 PM CST Tue Feb 20 2018)

SHORT TERM...

Tonight...Forecast Confidence is Medium...

Plume of moisture will continue to stream across SE WI well into
the evening...possibly a few hrs past midnight. This will only
serve to exacerbate the existing flooding. All rain will be out of
the state by early Wed mrng. Cold air will slowly filter into the
area overnight with temperatures steadily falling below freezing
from west to east. Depending on how long the rain lasts across far
SE WI and how quickly the cold air can make it that far east,
there may be a brief period of freezing rain in far SE WI around
06Z. At this time, even if it does happen, it should not be a big
deal since the precip should be ending about the time it gets cold
enough to cause problems.

LONG TERM...

Wednesday...Forecast confidence is high:

High pressure will bring some sunshine and colder temperatures on
Wednesday, with highs a couple degrees below normal.

Thursday and Friday...Forecast confidence is medium:

Warm advection ahead of approaching low pressure will bring a
chance of rain/snow on Thursday, with only a little precipitation
expected. The low will then move through Thursday night into
Friday, bringing widespread light precipitation. Models continue
to show a warm layer aloft, with near or below freezing
temperatures at the surface. A prolonged period of freezing rain
is possible Thursday evening into Friday morning, with up to 0.10"
of icing. This is worth keeping an eye on, as slick driving
conditions may be present for the Friday morning commute.
Temperatures are expected to warm enough Friday to melt any icing
by late morning.

Saturday through Tuesday...Forecast confidence is medium:

A stronger low pressure system is progged to move through later
Saturday into Sunday. This could bring some accumulating snowfall
to at least northwest portions of the forecast area, depending on
the track of the low. The majority of models would keep the precip
as mainly rain in the southeast.

A consensus of models suggests high pressure will result in mainly
dry weather for Mon/Tue. The ECMWF and Canadian are showing a wave
later Monday or early Tuesday though, which could bring a little
rain/snow to the area.

&&

MARINE...

Winds have become westerly this afternoon should remain offshore
into Wednesday before becoming northerly. Winds may gust near
small craft advisory levels overnight into early Wednesday
morning. Rain will move out of the nearshore areas of southeastern
Wisconsin tonight.

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...Flood Watch until 6 PM CST this evening for WIZ065-066-070>072.

LM...None.
&&

$$

Update...Boxell
Tonight/Wednesday and Aviation/Marine...Boxell
Wednesday Night through Tuesday...99



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.