FXUS63 KMQT 191125

Area Forecast Discussion
National Weather Service Marquette MI
725 AM EDT Sun Aug 19 2018

.SHORT TERM...(Today and tonight)
Issued at 439 AM EDT SUN AUG 19 2018

Under clear skies and light winds, patchy fog has formed early this
morning over mainly interior west half portions of Upper Mi. The fog
appears to be fairly shallow though as visibilities have been quite

Today, expect any remaining patchy fog to mix out around sunrise or
shortly thereafter as a southwest flow sets up across Upper Mi ahead
of an approaching frontal boundary over the Northern Plains. Warm
advection with this southwest flow will result in warmer temps
across much of the Upper Peninsula. Mid-level ridging will keep
conditions dry as high temps reach into the lower 80s across much of
the area, except for slightly cooler mid-upper 70s readings near the
Great Lakes shorelines due to the formation of lake breezes.
The HRRR model does indicate some increase in smoke across the
area from western U.S and Canadian wildfires, but it's not clear
what impact the smoke will have on sunshine/temps today. However,
this may be something for the day shift to keep an eye on.

Tonight, a gradual increase in cloud cover from west to east ahead
of the approaching frontal boundary from the Northern Plains will
allow min temps to stay warmer tonight. Expect readings ranging from
the mid 50s interior east to the lower 60s near the Great Lakes
shorelines. Persistent mid-level ridging will keep much of the area
dry again, but a few models indicate some isolated showers could
reach into western fcst area late tonight with the arrival of the
frontal boundary.

.LONG TERM...(Monday through Saturday)
Issued at 356 AM EDT SUN AUG 19 2018

To start off on daybreak Monday, weaker shortwave trough will be
crossing northern MN into Lk Superior while much stronger
shortwave trough settles to central Plains. Weak sfc trough tied
to northern stream wave slides across northern Upper Michigan
while strong sfc low sets up between Kansas City MO and Des Moines
IA. Could be some light showers on Monday morning over especially
northwest Upper Michigan, but steadier rain tied to northern wave
should be farther north over Lake Superior in right entrance jet
and coupled mid-level frontogenesis forcing region over Lk
Superior. By late afternoon, expect increased showers over west
half as the stronger system approaches from the southwest. Have
doubts on how much t-storms will occur. Since southeast winds off
Lake Michigan should result in sct-bkn low clouds think the
1000-1500j/kg of CAPE that models show by late Monday may be
overdone. Given the stronger system though will continue to
mention at least slight chance of t- storms Monday into Monday
evening. Greatest chances probably will be over southwest and
south central.

Blend of models indicate upper low and sfc low track over northern
Lower Michigan later Monday night into Tuesday which is an idea that
lines up with ECMWF/GFS ensemble mean. GEM-NH still remains on north
edge/stronger with sfc low, but even this model now keeps main track
out of eastern Upper Michigan. GEM-NH idea would track sfc low close
enough to bring widespread moderate rain to eastern Upper Michigan,
but otherwise just expect light rain for most of forecast area.
North-northwest winds look breezy on Tuesday for east half. Likely
that there will be hazardous conditions for small crafts on Lake
Superior and Lake Michigan along with high swim risk on Lake
Superior. Risk of seeing any wind advisories on land look low attm,
though it is not out of question if the sfc low ends up tracking
farther northwest as some recent ECMWF runs and GEM ensemble members
have shown.

Early week low pressure system looks progressive enough to allow for
mostly sunny skies to develop by Wednesday with diminishing winds.
After cooler conditions on Tuesday should see decent bounce back in
temps. Temps pop above normal on Thursday with many areas topping
80F again. Next chance of showers and t-storms moves back in on
Friday/Saturday as well developed shortwave/sfc low cross the

.AVIATION...(For the 12Z TAFS through 12Z Monday morning)
Issued at 722 AM EDT SUN AUG 19 2018

Any remaining MVFR/IFR fog should mix out of KIWD shortly aft 12Z
under light southerly winds. Otherwise, wildfire smoke will
continue to thicken over the area through the day today.
Precipitation along advancing Plains front should hold off until
aft 12Z Mon.


.MARINE...(For the 4 AM Lake Superior forecast issuance)
Issued at 439 AM EDT SUN AUG 19 2018

Winds will continue to be less than 15 kts through tonight, then
steadily increase. Gusty north winds will return to the nearshore
and open waters Monday Night/Tuesday as low pressure moves into the
area. Gusts as high at 30 knots are possible Tuesday afternoon until
the winds begin to relax Tuesday evening into Wednesday.

Upper Michigan...
Lake Superior...
Lake Michigan...


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