Area Forecast Discussion
Issued by NWS Marquette, MI

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
FXUS63 KMQT 161720

Area Forecast Discussion
National Weather Service Marquette MI
120 PM EDT Sun Jul 16 2017

.SHORT TERM...(Today and tonight)
Issued at 507 AM EDT SUN JUL 16 2017

WV imagery and RAP analysis indicated cyclonic nw mid/upper level
flow through the nrn Great Lakes between a ridge from the plains
into cntrl Canada and a trough from ern Canada. A shortwave trough
extending from s of James Bay to ern Lake Superior was quickly
pushing to the se. Any remaining tsra were along and south of the
sfc cold front into srn WI. High pressure over nw Ontario into ND
was building into the nrn Great Lakes with moderate nrly winds.
Radar indicated increasing weak returns between Marquette and
Munising with mainly some light drizzle possible, per Munising web

Today, expect any light pcpn over the north to diminish by around
12z. Satellite trends and forecast 950-850mb RH also suggest that
dry air will filter into the area from the north bringing clearing
by late morning or early afternoon. Even with abundant sunshine this
afternoon temps will struggle to around 70 over the south and into
the lower 60s north with onshore nrly flow off of Lake Superior.
Waves up to 3 or 4 feet, mainly early, will be high enough for a
moderate swim risk for the beaches of Marquette and Alger counties.

Tonight, with much drier air into the region, clear skies and
diminishing winds temps will fall off into the lower to mid 40s
inland with some isold cold sport perhaps into the upper 30s.
Increasing srly winds late tonight far west will bring rising temps.

.LONG TERM...(Monday through Saturday)
Issued at 321 AM EDT SUN JUL 16 2017

Throughout the bulk of the extended periods, the 500mb heights are
progged to be in a quasi-zonal pattern. This will allow for systems
to easily traverse the Northern Rockies east through the Great
Lakes/Ohio Valley. The mid-lvl ridge axis is progged to become
positioned over the Southern Plains, which will likely keep a
frontal boundary displaced along the northern periphery. The
wildcard will be any weak shortwaves that ride along the boundary
and possibly push this feature further south.

Mon/Tue: Southerly flow will advect warmer temps across the U.P.
with some downsloping effects further enhancing temps closer to Lake
Superior Mon. Operational guidance indicates a weak boundary will be
sliding southeast and could bring a chance for showers/thunderstorms
later Mon into Tue. Low-level moisture will increase late Mon, and
coupled with any thunderstorm activity could allow for some
efficient downpours from any stronger storms that develop late Mon.
Temps will likely return to the upper 70s to low 80s, but will hinge
on cloud cover and precip coverage/timing.

Wed-Sat: The boundary will likely meander through the region Wed,
but expected to push south with a weak surface ridge sliding east
from the Northern Plains to the U.P. This will bring a brief break
in precip chances later in the week; however, confidence remains
reduced given the overall longwave pattern still in a quasi-zonal
orientation. Temps throughout the remainder of the extended periods
will be seasonal with highs in the mid/upr 70s to around 80 and
overnight lows in the upper 40s to mid 50s.

.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
Issued at 120 PM EDT SUN JUL 16 2017

With high pres and associated dry air mass settling over the area,
VFR conditions will continue at KIWD/KCMX/KSAW thru this fcst

.MARINE...(For the 4 AM Lake Superior forecast issuance)
Issued at 507 AM EDT SUN JUL 16 2017

Nrly winds may gust from 20 to 25 knots early today as high pressure
builds into the region from the north. Otherwise, winds will stay at
or below 20 knots through the period.

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


LONG TERM...Beachler
MARINE...JLB is the U.S. government's official web portal to all federal, state and local government web resources and services.