FXUS63 KMQT 232031

Area Forecast Discussion
National Weather Service Marquette MI
431 PM EDT Sat Jun 23 2018

.SHORT TERM...(This evening through Sunday)
Issued at 249 PM EDT SAT JUN 23 2018

Split flow continues across N. America with the Upper Peninsula
squarely in between. A relatively stationary E-W oriented frontal
boundary sits along the northern periphery of Lake Superior this
afternoon. Sfc high pressure over Hudson Bay will continue to build
and push southward, which will bring the front through the area
overnight and tomorrow morning. Simultaneously, sfc low pressure
over the Lower Peninsula will stall and begin to fill. Both of these
features will bring slight chances of showers to portions of the
area. The front may kick off a few showers across eastern Lake
Superior and perhaps holding together into the NW UP late tonight
and tomorrow morning, while high-res models have picked up on a few
showers over the Bay of Green Bay and Delta/Menominee counties
during the same time frame so POPS have been added in there.

Some indications for overnight fog development, especially close to
the WI border. Observed dew points have been quite diverse this
afternoon, near 60 in western Gogebic/Ontonagon and in the low 40's
in and around Iron County which lowers confidence a little in fog
development there. Grids may be a little overzealous. Some
indications in high-res guidance for a few airmass thunderstorms
tomorrow afternoon just south of the CWA, and an isolated storm
sneaking in briefly cannot be ruled out.

.LONG TERM...(Sunday night through Saturday)
Issued at 412 PM EDT SAT JUN 23 2018

Surface high pressure and ridging aloft will be in control over
the region to start the long-term period. This will allow quiet,
benign weather conditions to prevail and for temperatures to
perhaps exceed initial guidance (bumped up highs on Monday to
account for this). Low pressure system parked over the Central
Plains will finally get the push it needs to approach the Upper
Great Lakes from a shortwave coming onshore in the PacNW,
although models have slowed down its approach. This would delay
the onset of precip, but, the best precip chances still look to
occur Tuesday into Tuesday night, with perhaps some lingering
showers and possible thunderstorms in the eastern U.P. early
Wednesday. As for QPF, forecast is still looking like widespread
total amounts approaching and exceeding a half of an inch Tuesday
into Wednesday, with closer to three-quarters of an inch possible
in the southern and western portions of the U.P. Right now,
primary concerns with this mid-week system is how much rain will
end up falling, potentially exacerbating any lingering issues from
the most recent significant rain event, and the potential for
lightning to impact ongoing outdoor recovery efforts. Current
indications are that any rain that falls during this time frame
will be spread out enough to not cause any major problems, but
still bears worth watching as this time period inches closer. Stay
tuned to future forecasts for the latest updates.

Into the end of next week, zonal flow aloft will likely prevail,
with perhaps some perturbations rippling through and bringing
additional rain chances. At this point though, models are too much
in disagreement to hang one's hat on any particular solution,
leaving the long-range outlook in the lower confidence category.
There is slightly higher confidence in the temperatures, with highs
looking to reach well into the upper 70s and lower 80s area-wide
by week's end.


.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 127 PM EDT SAT JUN 23 2018

VFR conditions will likely prevail at KIWD/KCMX/KSAW through this
forecast period with winds below 10 knots. However, as a cold front
approaches the area from the north overnight and tomorrow morning,
cloud coverage will increase and lower, with some indications of
MVFR cigs at CMX and IWD after 12Z tomorrow. The NAM would even
bring some fog/IFR cigs in at IWD/CMX late overnight but
confidence in this solution is low at this time.


.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 249 PM EDT SAT JUN 23 2018

Light winds under 15kt across Lake Superior today will increase out
of the ne to 15-20kt tonight in the wake of a passing cold front. As
high pres building over northern Ontario edges closer, winds will
gradually diminish to under 20kt on Sun, diminishing latest over far
western Lake Superior.


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


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