845
FXUS63 KMQT 280808
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
408 AM EDT Fri Jun 28 2024

.KEY MESSAGES...

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

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 316 PM EDT Thu Jun 27 2024

It`s a pleasant late June aftn across Upper MI under sfc high pres
centered over the western Great lakes. Temps generally range from 60-
65 along the Great Lakes to the lwr 70s F inland. Dwpts are
comfortably low, ranging from around 40 to around 50F. Cu has
developed away from stabilizing flow off of the Lakes, and a streak
of high clouds is spreading over western Upper MI. Off to the w,
water vapor imagery and RAP analysis show a well-defined shortwave
trof over the nw U.S. This feature will bring the next round of
shra/some tsra to Upper MI during Fri into Sat. Ahead of that trof,
a weaker shortwave across the Plains is generating shra and a few
tsra from ND across sw MN into western IA.

Clouds will be on the increase from w to e tonight. Shra associated
with the lead Plains wave should reach western Upper MI in the 09z-
12z time frame. Prior to that, a modest increase in 850mb theta-e
and increasing 850mb flow may support a few isold -shra across
western Upper MI after 06z. Will be warmer night tonight than last
night under increasing clouds and stirring winds. Expect min temps
ranging from around 50 e to 55-60F w.

&&

.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 /06Z TAFS THROUGH 06Z SATURDAY/...
Issued at 141 AM EDT Fri Jun 28 2024

VFR conditions to prevail through daybreak at all TAF sites with
gradual deterioration to MVFR starting at IWD by Fri 12Z. CMX and
SAW will follow with MVFR by late morning/early afternoon. SAW
has the best chance to lower to IFR by late afternoon and
evening. In addition, LLWS will be a threat mostly at IWD/CMX
this morning and afternoon as a low-level jet max moves across
the area.

&&

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

&&

$$

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