049
FXUS63 KMQT 282017
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
417 PM EDT Fri Jun 28 2024

.KEY MESSAGES...

- Rounds of showers are expected into Saturday and then Monday night
into Tuesday with quiet weather following each round.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 416 PM EDT Fri Jun 28 2024

Water vapor imagery and RAP analysis show a well-defined mid-level
low over eastern MT with wsw flow downstream into the Great Lakes.
In this wsw flow, a shortwave moving across Upper MI is responsible
for the shra that have been spreading w to e today. Most of the
rainfall has been on the light side. The clouds and shra have
resulted in a cool day with current temps mostly in the upper 50s
and lwr 60s F. The cool conditions and resulting lack of
instability, including for parcels lifted from anywhere above the
sfc, have prevented any tsra from developing. To the w, sfc low pres
is located in n central MN with a cold front extending ssw thru far
nw IA. Within 850mb theta-e ridge ahead of the front, shra/tsra are
developing from western IA into se MN.

Shra associated with aforementioned shortwave will be exiting the
eastern fcst area over the next few hrs. Attention then turns to the
convection developing to the sw. Under 850mb theta-e advection as
850mb theta-e ridge advects ne ahead of approaching cold front,
there should be additional shra/some tsra development ne thru WI
into mainly the se half of Upper MI. Additional shra/tsra, lower
coverage, will be possible along the cold front as it moves into
Upper MI during the night. With the instability that does build ne
into Upper MI limited, svr storms not expected. Temps tonight won`t
fall much from current readings. Min temps should be mostly in the
upper 50s and lwr 60s F.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
Issued at 407 AM EDT Fri Jun 28 2024

Active weather pattern continues through the next week as an
amplified pattern aloft translates to multiple weather systems
passing through the region into early June. A few showers linger
behind a cold front Saturday followed by high pressure sweeping over
the Great Lakes Sunday and Monday, allowing for some nice summer
weather. The next round of precipitation looks to be late Monday
into Tuesday, but the surface low associated with those showers
looks to not be particularly strong and also displaced well to the
north, so impacts should be relatively low. Model spread increases
beyond then, but a continued warm and wet pattern is expected to
continue.

By Saturday morning, the cold front will be just about past the UP,
a significant increase in speed from model guidance from just 24
hours ago. As such, PoPs fall off behind the front, with only
scattered to isolated precipitation expected for the remainder of
Saturday. High pressure will follow behind for the remainder of the
weekend as a ~1025mb surface high will be over southern Minnesota by
Sunday afternoon and over the Michigan Lower Peninsula by Monday
afternoon. This will lead to a couple of nice sunny days, though
Sunday will definitely be the cooler day of the two as cool
northerly flow aloft will keep highs mainly in the 60s Sunday, but
winds becoming southerly Monday will allow highs to rebound to
seasonal 70s. With clear skies allowing for efficient radiational
cooling overnight, bias-corrected MOS guidance hints at the
potential for some interior locations to fall to the upper 30s
Sunday morning and Monday morning.

Precipitation chances begin to ramp up Monday evening into
Tuesday as the next trough exits the Rockies and a surface low
passes generally through northern Ontario. The GEFS has trended
stronger with this low pressure, with a mean low now in the 990s
mb, but the trend in the path has been even further north,
almost to the Hudson Bay. As even the southernmost cluster of
lows remains well north of the UP, dynamics should be fairly
weak over the UP, so hazardous weather seems unlikely at this
time. Following the passage of showers, another dry period is
expected Wednesday, but to what extent that dry weather lasts is
uncertain as ensemble spread increases significantly, though a
pattern change is still not expected as the CPC outlooks that
the first half of July is still more likely to be warmer and
wetter than normal.

&&

.AVIATION /18Z TAFS THROUGH 18Z SATURDAY/...
Issued at 148 PM EDT Fri Jun 28 2024

Area of shra moving across Upper MI will be accompanied by and
followed by lowering cigs. At IWD, expect low MVFR to prevail thru
the fcst period, though IFR is a possibility this evening. MVFR cigs
may also scatter out to VFR for a time late tonight/Sat morning.
Bulk of shra activity has exited to the e of IWD, but potential for
a few shra exists thru the fcst period. Southerly wind should gust
upwards of 25kt this aftn. At CMX, Initial VFR will fall to low MVFR
in the next hr or so with potential for IFR to set in. However, IFR
is more likely to set in this evening and then to persist thru Sat
morning. LLWS will continue at CMX this aftn. The more persistent
shra will end in the next few hrs at CMX, but potential of a few
-shra will continue. At SAW, MVFR will fall to IFR this aftn and
then to LIFR this evening under moist/upsloping southerly winds.
Expect VFR to return Sat morning as winds shift to the nw with
fropa. The more persistent shra will end in the next few hrs at SAW,
but potential of a few -shra will continue.

&&

.MARINE...
Issued at 407 AM EDT Fri Jun 28 2024

As a cold front approaches from the west, southerly wind gusts
increase to around 25 kt across the lake beginning this morning,
with some gusts to around 30 kt in the eastern nearshores of Lake
Superior as winds flow downslope onto the lake. As winds veer
westerly behind the front on Saturday, wind gusts across the lake
briefly fall below 20 kt Saturday morning, but mixing behind the
front allows for northwesterly wind gusts to 25-30 kt over the
eastern half of the lake. The return of high pressure will keep wind
gusts below 20 kt Saturday night through Monday night before the
next system passes through northern Ontario, increasing the wind
gusts to around and above 20 kt into Tuesday. As the system lifts
northeast and out of the region Tuesday night, winds fall mainly
below 20 kt through the rest of the forecast period.

Long-duration southerlies today will cause waves over the northern
portions of the lake to increase to 4-6 ft, with some waves to 7
feet along the US/Canada border. The northwesterlies behind the cold
front passage will cause 5-8 ft waves over the eastern half of the
lake Saturday night. Thunderstorms will also threaten the lake today.

&&

.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
  Beach Hazards Statement until 10 PM EDT this evening for
     MIZ014.

Lake Superior...
None.
Lake Michigan...
None.

&&

$$

SHORT TERM...Rolfson
LONG TERM...GS
AVIATION...Rolfson
MARINE...GS