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000 
FXUS63 KMKX 240818
AFDMKX

Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
318 AM CDT Tue Oct 24 2017

.DISCUSSION...

Today and tonight...Forecast confidence is high:

Rain on the back side of strong low pressure will continue into
this morning. The rain will wind down northwest to southeast mid-
morning into the afternoon as drier and colder air advects into
the area. Clouds will hang on through the day today, but are then
expected to clear out quickly west to east during the evening
hours. 

Highest wind gust potential today is a bit tricky given limited
mixing early due to clouds and precip, but increased mixing later
as colder air advects in. Gusts look borderline for a Wind
Advisory, but close enough to leave the advisory as is. 

Clouds will move back in from the northwest later tonight as a
quick moving shortwave approaches. Models show a little precip
with this waves as well. It will take a little while for the low
levels to saturate before any precip has a chance to make it to
the ground. Soundings do look saturated enough by the early
morning hours for some low precip chances. Left rain/snow mention
going, with temps in the lowest 1-2 kft right on the border of
rain or snow. 

Wednesday - Confidence...Medium
Potent 200-300 millibar jet streak will put southern WI right in
the vicinity of the left front quad. Impressive 500 millibar wave 
rides through as well during the morning hours. Bufkit soundings
are showing the GFS drier within the column with window of low
level saturation brief if at all. Meanwhile the NAM saturates the
column for a longer period in the morning though still a close
call on precip type with wet bulb considerations. Will have both
rain and snow in the grids. QPF amounts are on the low side. Not 
expecting any snow accumulation with ground still warm. This 
should all exit for the afternoon hours with low level RH 
lingering longer than the 700 RH so clouds may be stubborn for a 
time in the afternoon. 

Thursday - Confidence...Medium
Surface ridge shifts to the east and sets up a milder return flow
with precip associated with next low remaining to our north or
northwest. Some disagreement amongst the models on how warm 925
temps will rebound to. The GFS is the warmest with readings 
pushing 11c while the NAM and ECMWF keep readings more in the 
middle single digit range celsius. Will lean towards the GFS 
MOS/Superblend guidance at this time.

Thursday night through Sunday - Confidence...Low to Medium
Another mid level trough will carve out across the Upper Midwest 
and linger this period. The GFS is actually the slowest suggesting
the influence of the circulation could linger into Sunday while 
the ECMWF is a bit more progressive. Initial precip on Thursday 
night shows a max across northern or central WI from the GFS/GEM 
and ECMWF while the NAM shows more across southern WI. This 
initial batch looks warm enough to remain all liquid. Colder air 
is proggd to wrap in for the weekend as the low heads to the 
northeast so potential of a mix returns. QPF amounts not all that 
impressive.

Monday - Confidence...Medium
Mid level ridging finally works in and there is consensus between
the GFS and ECMWF to go with the dry look of the Superblend pops.

&&

.AVIATION(09Z TAFS)...Rain will persist into this morning across 
the area, winding down northwest to southeast mid-morning into the
afternoon. Most places will have MVFR ceilings today, though some
IFR spots possible this morning. Also, seeing a location or two 
that are slow for ceilings to lower at the moment, but expecting 
these holdouts to drop to MVFR in the next couple hours. Northwest
winds are still expected to be quite gusty today.

Clouds will clear out west to east this evening. More clouds are
expected to move in from the northwest later tonight into
Wednesday morning as a quick moving wave approaches. Some light
precip is likely with this wave, with a period of snow or 
rain/snow mix possible. No accumulations are expected given mild 
ground temps and borderline air temps for snow. 

&&

.MARINE...Gale force northwest winds are likely today on the back 
side of strong low pressure. The strong winds will slowly wind 
down during the evening and early nighttime hours. Highest waves 
will be toward open waters due to the offshore nature of the 
winds. Left the current marine Small Craft Advisory and Gale 
Warning timing as is. 

Winds could hit advisory levels again Thursday night into Friday
as low pressure moves through the area. 

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...Wind Advisory from 7 AM this morning to 7 PM CDT this evening 
     for WIZ046-047-051-052-056>060-062>072.

LM...Small Craft Advisory from 6 AM to 9 AM CDT this morning for 
     LMZ643>646.

     Gale Warning from 9 AM this morning to 4 AM CDT Wednesday for 
     LMZ643>646.

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