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
000
FXUS63 KMQT 210744
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
344 AM EDT Fri Apr 21 2017

.SHORT TERM...(Today and tonight)
Issued at 332 AM EDT FRI APR 21 2017

Light snow and rain continues early this morning near Lk Superior
as upper level trough and sfc low move slowly east. Highest snow
totals since yesterday morning seem to have occurred over higher
terrain of Keweenaw Peninsula with 2-3 inches reported as of late
last evening before the snow tapered off. Have had 0.5 to 1 inch
of snow at our office in Negaunee township since late last
evening. Most the snow has occurred on grassy and elevated
surfaces as roads in most areas have stayed mainly just wet.

As of 3 am the sfc low of 1006mb is over Gore Bay near west side of
Georgian Bay. Sfc high upstream is as close as southern Mantioba
into North Dakota. Sfc low moves to vcnty of Ontario/Quebec border
by late morning. Cool/moist northerly flow btwn the high and
departing low will keep clouds and some light rain/snow showers over
mainly ncntrl to eastern forecast area. Drier air noted upstream
over much of northern Ontario arrives by aftn and should see
decreasing clouds midday through the rest of the aftn with clear
skies expected by sunset. North winds off Lk Superior will keep
conditions cool in the low to mid 40s near Lk Superior. Inland
though readings should reach 50s with downslope winds and clearing
earlier in the day. Only main weather issue will be gusty N to NW
winds up to 30 mph this morning closer to Lk Superior. Winds will
diminish steadily this aftn as the high moves closer.

High moves overhead tonight and with clear skies/light winds should
see min temps fall into the lower 20s over interior west. Warmest
readings tonight in the mid 30s will be near the relatively warmer
Great Lakes.

.LONG TERM...(Saturday through Thursday)
Issued at 344 AM EDT FRI APR 21 2017

Nam shows a rex block pattern over the plains 12z Sat with troughing
in the lower Great Lakes and trough off the Pacific NW. The ridge
causing the rex block over the plains breaks down quickly with
troughing moving into the upper Great Lakes and Mississippi River
Valley 12z Sun. Nam shows some deeper moisture and 850-500 mb
q-vector convergence moving through Sat night through Sun night.
Does not look like a whole lot of moisture to work with though and
continued with light amounts for pcpn and low chance pops. Overall,
not too many changes to the going forecast were made.

In the extended, GFS and ECMWF show a shortwave trough over the
Rockies 12z Mon that moves into the upper Great Lakes 12z Tue. Upper
troughing remains into 12z Wed with colder air aloft at 850 mb of
-4C to -7C moving over Lake Superior. A stronger 500 mb trough digs
into the Rockies 12z Thu into Fri. Continues to look unsettled with
temperatures remaining below normal for this forecast period.
&&

.AVIATION...(For the 06Z TAFS through 06Z Friday night)
Issued at 142 AM EDT FRI APR 21 2017

As low pres over northern Lake Huron continues to move e, conditions
will begin to improve overnight, but much more dramatically this
morning as much drier air moves into the Upper Great Lakes.
KIWD/KSAW should remain LIFR overnight, but some periods of IFR are
possible. At KCMX, IFR conditions will improve to MVFR during the
night. Lingering -sn/-ra will diminish/end. Low clouds will then
clear out to VFR conditions from w to e this morning with VFR
conditions then persisting thru the end of the fcst period.
Northerly winds will be gusty to 20-25kt at KSAW today.
&&

.MARINE...(For the 4 AM Lake Superior forecast issuance)
Issued at 332 AM EDT FRI APR 21 2017

N to NW winds could gust over 30 kts this morning on eastern half of
Lk Superior as sfc low departs Upper Lakes region. High pressure
brings winds back down to less than 25 kts tonight through Sun.
Winds increase to 30 kts late Mon into Tue as low pressure system
moves in from the Central Plains. Strongest winds look to occur over
east half of Lk Superior. Winds diminish to 25 kts or less late Tue
into Wed as high pressure moves back into the region from northern
Canada.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.
&&

$$

SHORT TERM...JLA
LONG TERM...07
AVIATION...Rolfson
MARINE...JLA



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.