NWS Milwaukee Forecast Discussion
169
FXUS63 KMKX 161000
AFDMKX
Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
400 AM CST Mon Dec 16 2024
.KEY MESSAGES...
- Dense fog remains a concern over south-central, southwestern,
and southeastern Wisconsin this morning.
- Low clouds and drizzle this morning. A cold front passes late
this morning, with breezy west winds and slight chances for a
rain shower behind it this afternoon.
- 50-60% chances for a light snow Tuesday evening into Wednesday
morning. Currently expecting less than an inch of snow to fall
in this window, but could impact the Wednesday morning
commute.
- Cooler mid to late week. Increasing chances for accumulating
snow Thursday into Thursday night.
&&
.SHORT TERM...
Issued 400 AM CST Mon Dec 16 2024
Today through Tuesday:
Currently observing low clouds and areas of dense fog across
the entire CWA, with the exception of east-central WI (though
the fog could possibly fill in there as well). Fog is expected
to linger until a cold front crosses the region late this
morning, veering winds from south to west and bringing a slight
chance of drizzle / light rain. West winds become gusty behind
the front in the mid to late afternoon (gusts to 25-30 MPH). Dry
weather expected overnight tonight under mostly cloudy skies.
A bit cooler behind the front on Tuesday, with highs in the
upper 30s to around 40, west winds gradually decelerate. Dry
weather likely to continue until Tuesday evening, which is
discussed in detail in the Long Term section of this AFD.
Sheppard
&&
.LONG TERM...
Issued 400 AM CST Mon Dec 16 2024
Tuesday night through Sunday:
Weak low pressure tracking from the southern plains into the
Ohio River valley coupled with strong high pressure over
southern Canada work together to create a zone of 700mb FGEN
centered over our CWA Tuesday evening into Wednesday morning,
resulting in a light snowfall event. Models show decent
agreement on DGZ saturation and a sub-freezing air column
(indicating that snow is likely the only precip type), and agree
on a swath of light QPF. Our forecast calls for a region-wide
light snowfall of less than 1 inch, beginning after sunset
Tuesday, peaking in intensity between midnight and 6 AM
Wednesday, then tapering off from west to east Wednesday
morning. Though this is only a light snowfall, the timing of it
would allow for impacts to the Wednesday AM commute.
Strong high pressure over Manitoba Canada / the Dakotas on
Wednesday will allow for northwest airflow and Cold Advection,
sending Wednesday night`s low temperature into the teens. A
clipper system tracking from the Dakotas into Illinois Thursday
/ Thursday night is expected to deliver another batch of
snowfall, likely amounting to more than the prior system (too
early to estimate snowfall amounts, but could easily deliver an
inch of snow to our CWA, perhaps even multiple inches if the
system tracks just right).
Several days with highs in the 20s / lows in the teens to single
digits are likely following Thursday`s potential snowfall.
Sheppard
&&
.AVIATION...
Issued 400 AM CST Mon Dec 16 2024
Widespread LIFR ceilings and dense fog are ongoing across the
region. A cold front will cross the region later this morning,
veering winds from south to west, then obtaining gusts to
roughly 25 kt in the mid to late afternoon. Model guidance
suggests LIFR could easily linger through noon today, increasing
to IFR in the mid afternoon (behind the front), then to Fuel Alt
/ MVFR after dark tonight. A few periods of light drizzle or a
brief light rain shower may occur between now and this
afternoon. Dry weather likely underneath the broken MVFR clouds
tonight.
Sheppard
&&
.MARINE...
Issued 400 AM CST Mon Dec 16 2024
Patchy dense fog will continue into this morning across the
southern half of the lake, possibly intensifying / becoming more
widespread later this morning before dissipating this afternoon as
a cold front crosses the lake. Winds veer west behind the front
and become gusty (roughly 30 kt). A few gusts to gale force will
be possible late this afternoon through early Tuesday morning
across the entire lake as low pressure of 29.4 inches moves from
Ontario into Quebec and high pressure of 30.3 inches moves from
the central Plains into the Ohio river valley.
As the aforementioned high and low pressure systems continue
eastward, westerly winds decelerate Tuesday. Modest northwest
winds expected Wednesday as high pressure of 30.5 inches tracks
eastward across southern Manitoba.
Sheppard
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...Dense Fog Advisory...WIZ046-WIZ047-WIZ056-WIZ057-WIZ058-WIZ062-
WIZ063-WIZ064-WIZ067-WIZ068-WIZ069 until 9 AM Monday.
LM...Dense Fog Advisory...LMZ080-LMZ644-LMZ645-LMZ646-LMZ669-LMZ671-
LMZ673-LMZ675-LMZ777-LMZ779-LMZ870-LMZ872-LMZ874-LMZ876-
LMZ878 until 9 AM Monday.
Small Craft Advisory...LMZ643 until noon Monday.
&&
$$
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