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 240721

Area Forecast Discussion
National Weather Service Marquette MI
221 AM EST Fri Nov 24 2017

.SHORT TERM...(This evening through Friday)
Issued at 406 PM EST THU NOV 23 2017

WV imagery and RAP analysis indicated a mid/upper level trough over
Quebec and a ridge from the sw CONUS into the nrn plains resulting
in nw flow through the nrn Great Lakes. Upstream, a vigorous
shortwave trough was moving through the Pacific northwest. At the
surface, a ridge from northwest Ontario into Lake Superior was
sliding to the east as a 992mb low moves into srn Saskatchewan. A
warm front extended southward through the cntrl Dakotas. Vis loop
showed mostly clear skies over most of the cwa with some lingering
clouds north from moisture off of Lake Superior.

Tonight, after a period of additional clearing north this evening as
winds back to the southwest, clouds will increase as mid level
WAA/isentropic ascent shifts into Upper Michigan. However, any pcpn
is expected to remain over northern Lake Superior or northern

Friday, Rain chances will increase during the morning as the WAA
regime strengthens further. However, confidence in pcpn chances is
still low given potential of a lingering dry 900-700mb layer, per
fcst soundings. The best chance for widespread pcpn will be during
the afternoon from west to east as the shortwave and cold front
approaches with moderate to strong 700-500mb fgen moving through
the cwa. Since moisture inflow will still be limited, QPF values
only around a tenth of an inch are expected. The WAA will help
push temps into the mid and upper 40s, especially for downslope

.LONG TERM...(Saturday through Thursday)
Issued at 220 AM EST FRI NOV 24 2017

Nam shows a 500 mb ridge across the western U.S. and troughing in
the ern half of the U.S. 12z Sat. This ridge slowly moves into the
plains by 12z Mon. Lake effect winds down on Sat and then quiet
weather for the rest of the forecast period.

In the extended, GFS and ECMWF show a 500 mb trough on the west
coast, a broad ridge across the plains 12z Mon. Troughing moves into
the northern plains 12z Tue with a closed low over the desert sw.
Cold air moves through the area on Tue with this trough. The
troughing moves into New England on Wed as another trough moves into
the central and southern plains. More troughing moves into the
northern plains 12z Thu which moves into the upper Great Lakes on
Fri. Above normal temperatures will continue for this forecast
period with brief periods of lake effect pcpn.

.AVIATION...(For the 06Z TAFS through 06Z Friday night)
Issued at 1222 AM EST FRI NOV 24 2017

VFR conditions will give way to MVFR conditions on Fri afternoon
with a lowering of ceilings under areas of rain developing ahead of
an approaching cold front from the west. Winds turning to an upslope
westerly direction will favor KCMX for possible IFR conditions for a
brief time Fri afternoon. LLWS will continue at all sites into Fri
morning as a low-level wind max moves across the area.

.MARINE...(For the 4 PM Lake Superior forecast issuance)
Issued at 406 PM EST THU NOV 23 2017

Westerly winds of 15 to 25 knots will back to the south late tonight
into Friday at 20 to 30 knots with gale force gusts to 35 knots
expected. So a gale warning remains in effect from late tonight into
Friday afternoon for most of Lake Superior. On the back side of the
strong low pressure system additional gales of 35 to 40 knots are
possible on colder northwest flow into the area. Winds are expected
to remain in the 20 to 30 knot range through at least mid weak.

Upper Michigan...
Lake Superior...
  Gale Warning until 10 AM EST /9 AM CST/ this morning for

  Gale Warning from 7 PM this evening to 5 AM EST Saturday for

  Gale Warning from 7 PM EST /6 PM CST/ this evening to 1 AM EST
     /midnight CST/ Saturday for LSZ240>245-263-264.

Lake Michigan...
  Gale Warning until 4 PM EST this afternoon for LMZ221-248-250.



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