Area Forecast Discussion
Issued by NWS Marquette, MI

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
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 190822
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
422 AM EDT Tue Mar 19 2024

.KEY MESSAGES...

- Off and on light snow showers today, with gusty northwest
  winds developing by afternoon, especially in the Keweenaw and
  near Lake Superior.
- Lake-effect snow continuing into Thursday.
- Blustery winds continue into Wednesday.
- Northwest high-end gales and heavy freezing spray expected tonight
  and Wednesday across central and eastern Lake Superior.
- Another shot for snow comes Thursday night/Friday.

&&

.SHORT TERM /THROUGH THIS AFTERNOON/...
Issued at 216 AM EDT Tue Mar 19 2024

Radar imagery this morning showed a wave of isentropically forced
precip shifting east through the forecast area. A quick look at
webcams show some light snow accumulations on roadways here and
there. Snow amounts observed here at our office outside of Negaunee
have only measured 0.3 inches. Overnight temperatures have been
mild, and most surface observations have been in the 20s.

As we press through the day today, favorable location in relation to
the jet streak will support additional snow shower development over
mostly the east this morning. Most of the region should see a break
in activity this morning, followed by what appears to be dinurally
enhanced shower activity as another shortwave within the broad
cyclonic aloft pivots through, all before a transition to lake
effect snow. Deep moisture under inversions as high as 7k feet
should support some good snow showers here and there, but given the
cold air really won`t move in until tonight, significant
accumulations aren`t expected. Overall thinking is mostly an inch or
less today with the higher amounts being over the east half. Gusty
winds will begin developing by late morning/afternoon from west to
east. Windiest spots will be the Keweenaw and near Lake Superior,
where 30-35 mph gusts will be possible. Elsewhere, the northwest
winds may gust to 25 mph this afternoon.

&&

.LONG TERM /TONIGHT THROUGH MONDAY/...
Issued at 422 AM EDT Tue Mar 19 2024

Upper air pattern consists of a 500 mb closed low in the desert sw,
a ridge in the western U.S. and a broad 500 mb trough in the east
half of the U.S. 00z Wed. The closed low gets kicked out into the
southern plains as a shortwave 00z Thu and onto the Gulf Coast 12z
Fri as a broad northern branch trough settles into the Great Lakes
region. Comparing models of NAM and GFS and ECMWF, 850 mb
temperatures fall from -10C to -14C 00z Wed to -16C to -20C 12z Wed
which stays that way through 00z Thu and then falls further to 18C
to -22C 12z Thu. Warming then takes place 00z Fri, but with Lake
Superior being around 2C to 3C, this is definitely enough lake-850
mb delta-t for LES again with northwest flow. Issued winter weather
advisory 00z tonight until 18z Wed for Alger, Luce and N.
Schoolcraft due to combo of blowing snow and snow amounts. Snow will
be fluffy with inversion heights over the ern cwa up to 6000 feet or
so and DGZ has plenty of omega lift in it, so fluffy snow with
strong winds will blow it around. Could see 3-5 inches of snow there
as well, so thought advisory was warranted. Will also be some
lakeshore flooding and minor beach erosion in Alger and Luce
Counties and issued a lakeshore flood advisory for this as waves
could be as high as 15 feet or so.

In the extended, the GFS and ECMWF show a 500 mb split flow regime
with a southern trough in the lower Mississippi River Valley and a
northern broad trough across the upper Great Lakes region 12z Fri.
Northern branch troughing remains over the upper Great Lakes 12z Sat
with a closed 500 mb low off the Pacific NW coast 12z Sat.
Troughing moves into the western U.S. 12z Sun and into the Rockies
12z Mon. A shortwave kicks out of the trough 12z Tue into the lower
Missouri River Valley and becomes negatively tilted and heads
towards the upper Great Lakes which could cause a significantly
strong storm to move into the area Tue. Temperatures look to be
below normal through most of this forecast period with temperatures
going to near normal on Monday and Tuesday. Looks like pcpn will be
above normal for this forecast period with some snow on Fri, chance
of snow on Sun and then rain and snow for Mon into Tue.

&&

.AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/...
Issued at 125 AM EDT Tue Mar 19 2024

Light snow associated with a disturbance has already spread across
most of the w and c portions of Upper MI. In its wake, expect VFR to
prevail overnight at IWD/CMX/SAW. During today, MVFR cigs should
develop at all terminals soon after sunrise. While those cigs are
expected to lift to just above 3000ft in the aftn, MVFR cigs may
hold on thru the day. Sct -shsn will begin to develop across the
area during the day under cyclonic flow. Vis may drop to briefly to
MVFR at times. As incoming air mass becomes increasingly colder
tonight, lake effect shsn will become more widespread with greater
fluctuations in vis btwn IFR and VFR possible. NW winds will be
gusty to 25-35kt today into tonight at all terminals, strongest at
CMX.

&&

.MARINE...
Issued at 422 AM EDT Tue Mar 19 2024

Next gale event begins this afternoon with northwest winds
increasing to 30 knots this morning and then gales up to 45 knots
tonight into Wednesday with more cold air and tighter pressure
gradient. Gale warning will continue for most of Lake Superior.
Additionally, the combination of cold air and strong winds will also
cause heavy freezing spray and a heavy freezing spray warning was
issued as well. Winds decrease late Wednesday night, coming in at or
below 20 knots the rest of the week before increasing to 20 to 30
knots Friday night and Saturday. Will have to watch a strong storm
system for early next week as it approaches from the southwest and
could be gales Sunday night into Monday.

&&

.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
  Winter Weather Advisory from 8 PM this evening to 2 PM EDT
     Wednesday for MIZ006-007-085.

  Lakeshore Flood Advisory from 11 PM this evening to 2 PM EDT
     Wednesday for MIZ006-007.

Lake Superior...
  Heavy Freezing Spray Warning from 11 PM EDT /10 PM CDT/ this
     evening to 8 PM EDT /7 PM CDT/ Wednesday for LSZ162-
     240>251-263>267.

  Small Craft Advisory until 8 PM EDT /7 PM CDT/ this evening
     for LSZ240>242.

  Gale Warning from 8 PM EDT /7 PM CDT/ this evening to 11 AM
     EDT /10 AM CDT/ Wednesday for LSZ240>242-263.

  Small Craft Advisory until 2 PM EDT this afternoon for LSZ243-
     244.

  Gale Warning from 2 PM this afternoon to 11 PM EDT Wednesday
     for LSZ243>251-264>267.

  Small Craft Advisory from 11 AM this morning to 2 PM EDT this
     afternoon for LSZ245>251.

Lake Michigan...
  Small Craft Advisory from 11 PM this evening to 8 PM EDT
     Wednesday for LMZ221-248-250.

&&

$$

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


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