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Area forecast discussion
National Weather Service Gaylord Michigan
336 PM EDT Mon Oct 21 2019

Near term...(through tonight)
issued at 335 PM EDT Mon Oct 21 2019

..windy and showery...

High impact weather potential: very gusty winds will lead to
Lakeshore flooding issues tonight and through Tuesday.

Pattern synopsis/forecast: impressive 998 mb low pressure system
is over Iowa/southern Minnesota this afternoon. Occluding boundary
arcs into Illinois then continues south/southwestward into eastern
Texas as a cold front. Widespread batch of rainfall continues to
pivot northward around the low...across Michigan into the upper
Midwest...driven by strong warm advection and system dynamics.
First batch of showers is quickly lifting up through the forecast
area this afternoon, followed by a brief break, while additional
showers are filling up upstream across Lake Michigan into southeast
Wisconsin. Pronounced dry slot is punching up through SW
Wisconsin and will be arriving here later this evening.

Tonight: still no major changes to the going forecast. Deep low
pressure will migrate up into far Western Lake Superior driving
the occluding boundary up through the region by late evening/early
overnight. Several more rounds of showers will pivot up through
the forecast area through the evening hours before well
pronounced dry slot punches across and brings a temporary end to
precip. Wrap around showers begin to press back into western areas
toward Tuesday morning. Although lightning activity has diminished
upstream in the last few hours, some thunder remains a possibility
as a narrow modest instability ribbon slides through along the
edge of the dry slot.

Biggest impacts continue with marine issues, specifically
Lakeshore flooding. Winds will ultimately veer southwesterly later
tonight into Tuesday focusing Lakeshore flooding issues over to
the Lake Michigan side. But, we have received reports of dock
damage in Northport...on the eastern side of Leelanau County
coming off Grand Traverse Bay. So, will put them into an advisory
starting now and running through Tuesday.

&&

Short term...(tuesday through thursday)
issued at 335 PM EDT Mon Oct 21 2019

..windy, rainy & cooler through midweek...

High impact weather potential: Lakeshore flooding/beach erosion
concerns continue Tuesday-Wednesday, mainly on Lake Michigan.

Pattern synopsis/forecast: attention revolves around vertically
stacked low pressure expected to be situated over northern Wisconsin
at the start of the period with broad cyclonic flow evident across
the Midwest and Great Lakes region. This system will continue its
northward progression into Ontario through Wednesday. While frequent
showers are expected, along with a return to chillier conditions,
continued gusty winds will pose the greatest potential impact in
terms of more Lakeshore flooding and beach erosion concerns.

Primary forecast concerns/challenges: continued wind concerns,
falling temperatures and renewed lake-aided showers Tuesday through
Wednesday.

Cold air advection will become the rule Tuesday through Wednesday
across northern Michigan as low pressure continues its northward
progression into Ontario through this time frame. As a result,
cooler air is expected to be filtering into the region (h8 temps
falling to -2 to -3 c by Tuesday evening/overnight) leading to
increased lake induced instability, which combined with pockets of
deeper moisture rotating through the back side of the system should
be plenty of support to produce additional showers Tuesday morning
through much of the remainder of the day into Tuesday night and even
at times right on through Wednesday morning - most numerous/steady
downwind of Lake Michigan/Superior in west-southwest flow lake
belts. Continued showers downwind of the lakes early Wednesday
should gradually give way to drier conditions as weak warm air
advection slowly takes over, most noticeably Wednesday afternoon as
mid-level heights also begin to rise in conjunction with weak mid-
level ridging working its way overhead.

Lakeshore flooding/beach erosion concerns: winds veer southerly
tonight while perhaps relaxing just a bit before turning more
southwesterly Tuesday morning through Wednesday, once again picking
up speed with gale force gusts anticipated on much of Lake Michigan.
Lakeshore flooding/beach issues transition to the Lake Michigan side
during this time. Winds finally begin to notably relax late
Wednesday afternoon into Wednesday evening, likely bringing an end
to the Lakeshore/beach issues.

High temperatures Tuesday ranging from the upper 40s to low 50s area-
wide, although with cloudy/rainy/windy conditions, will likely feel
several degrees cooler than that. Temps fall a few more degrees for
Wednesday with highs ranging from mid 40s inland to near 50 at the
coasts.

Long term...(thursday night through monday)
issued at 335 PM EDT Mon Oct 21 2019

Primary forecast concerns...precip chances late Wednesday into
Thursday

A positive tilt upper-level trough over the central Continental U.S. Will
progress east as a strong cyclone continues to move NE away from
Hudson Bay. Surface high pressure builds mainly to our south and
west heading into the weekend. High temps across northern Michigan
are expected to stay in the low to mid-40s before warming into the
low-50s by Sunday. Chilly overnight lows are also in store Thursday
and Friday nights, potentially dropping into the upper-20s for some
during that time. The chance for showers exists from the start of
the period mainly into Thursday afternoon. While low temps will be
near freezing Thursday morning, the chance for winter/mixed precip
remains uncertain. Another system could move to our north through
Ontario late in the period, which could bring the next main chance
for precip.

&&

Aviation...(for the 18z tafs through 18z Tuesday afternoon)
issued at 147 PM EDT Mon Oct 21 2019

Deepening surface low pressure is over southeast Minnesota this afternoon
with a tightening pressure gradient and increasing southeast winds across
Michigan. This system will drive some rainfall up through northern
Michigan this afternoon into this evening. Bigger issue continues
to be gusty winds. Southeast gusts pushing 30 knots or better are
expected to develop across the area for the next several hours,
diminishing some as we get into the evening. However, winds veer
south and southwesterly later tonight going into Tuesday with
gustiness continuing.



&&

Marine...
issued at 335 PM EDT Mon Oct 21 2019

Gale force wind gusts will continue to impact the lakes through
Tuesday before winds/waves begin to subside Tuesday night into
Wednesday.



&&

Apx watches/warnings/advisories...
Michigan...Lakeshore Flood Warning until 4 am EDT Tuesday for miz024-030-
036-088-096-097.
Lakeshore flood advisory from 2 PM Tuesday to 8 am EDT Wednesday
for miz016-020.
Lakeshore Flood Warning from 2 am Tuesday to 8 am EDT Wednesday
for miz025-031.
Lakeshore flood advisory until 4 am EDT Tuesday for miz018-042.
Lakeshore flood advisory until midnight EDT Tuesday night for
miz095.
LH...Gale Warning until 5 am EDT Wednesday for lhz346>349.
Gale Warning until 5 am EDT Tuesday for lhz345.
Lm...Lakeshore Flood Warning from 2 am Tuesday to 8 am EDT Wednesday
for lmz346.
Gale Warning until 5 am EDT Wednesday for lmz323-341-342-344>346.
Ls...Gale Warning until 7 PM EDT Tuesday for lsz321-322.
&&

$$

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