Area Forecast Discussion
Issued by NWS Marquette, MI

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FXUS63 KMQT 272352

Area Forecast Discussion
National Weather Service Marquette MI
752 PM EDT Thu Oct 27 2016

.SHORT TERM...(This evening through Friday)
Issued at 348 PM EDT THU OCT 27 2016

Main issues in the short term are on Fri as a 1001mb SFC low moves
to just NW of Lake Superior by late Fri and pushes a 1024mb ridge,
currently over the area, to the east. This will sharpen up the
pressure gradient and increase southerly 925mb winds up to 45kts,
strongest over the eastern CWA downwind of Lake Michigan. Expect
gales over Lake Michigan and eastern Lake Superior along with gusts
of 25-35mph near Lake Michigan and in downsloping areas near central
and eastern Lake Superior on Fri afternoon and evening. Rain showers
are possible Fri due to isentropic ascent and a shortwave, but very
dry mid levels are going to keep most of Upper MI dry. Best chances
for rain will be over Lake Superior and into eastern Upper MI.

.LONG TERM...(Friday night through Thursday)
Issued at 441 PM EDT THU OCT 27 2016

Friday night, expect the rain over the east half of the cwa to
diminish during the evening as the mid level 305K-310K band of
isentropic quickly moves off to the east. Otherwise, mild conditions
will prevail as low pressure moves through nrn Ontario as min
temperatures remain in the upper 40s to lower 50s.

Saturday, with zonal mid/upper level flow through the nrn Great
Lakes, a weak shortwave trough and band of 800-600 mb fgen will
support an area of pcpn from nrn WI into portions of Upper Michigan.
Since there is some uncertainty with the location of the pcpn band
(GFS/GEFS is farther north than the NAM/ECMWF/SREF) only chance pops
were mentioned. Some light lake effect rain showers may be possible
Saturday night as colder air (850 mb temps to near -2C) move in with
nnw flow behind a cold front.

Sunday, high pressure will build over the area but with low level
moisture below a strengthening inversion, mostly cloudy skies will

Monday, Breezy south winds with mild conditions are expected as a
strong low moving into nrn MN pushes 850 mb temps to around 11C.
Expect highs well above normal in the mid to upper 50s. Rain chances
will arrive as the shortwave and front move through. However, models
suggest that the higher QPF/POPS will remain north of the cwa.

Tuesday-Thursday, look for continued above normal temps with a
mainly zonal pattern keeping the colder air well to the north. There
is low confidence in potential for light pcpn with weaker shortwaves
brushing the area.

.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 752 PM EDT THU OCT 27 2016

Initial MVFR conditions at KIWD/KCMX/KSAW should transition to VFR
by late evening at KIWD and KCMX and remain VFR for the remainder of
the fcst period, though there is some concern that lower cigs could
occur at times given the lower clouds present upstream. MVFR cigs
will likely persist at KSAW for the majortity of tonight and
probably thru Fri, aided by an upslope wind component. Tightening
pres gradient will lead to gusty winds to 20-30kt on Fri, mainly at
KIWD/KSAW. May see a period of LLWS at KIWD Fri morning before
inversion weakens.

.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 348 PM EDT THU OCT 27 2016

SW winds increase late tonight ahead of developing low pressure
system over the northern Plains. South winds will increase to 20-35
kts on Fri, strongest on eastern Lake Superior where gale gusts are
expected Fri afternoon and evening. The low is expected to cross
over or near Lake Superior Fri night, shifting the winds to NW to 20-
30 knots late Fri night. Winds will gradually diminish to under 20
knots through the day Saturday. Another round of strong S-SE winds
to 30-35 kts are expected on Mon out ahead of low pressure tracking
across the northern Plains. Gales may occur over eastern sections
Mon afternoon into Mon evening. The low will cross Lake Superior by
Tue morning shifting the winds to W and there may be gales during
this time as well.

Upper Michigan...
Lake Superior...
  Gale Warning from 3 PM to 11 PM EDT Friday for LSZ249>251-266-

Lake Michigan...
  Gale Warning from 3 PM Friday to 2 AM EDT Saturday for LMZ221-



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