129
FXUS63 KMQT 161119
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
719 AM EDT Thu May 16 2024

.KEY MESSAGES...

- Unsettled weather returns to finish the work week with rain
  showers developing this morning and continuing through the
  evening. There is a chance for some rumbles of thunder into
  the afternoon and evening.

- Showers and thunderstorms return this weekend and early next
  week.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 718 AM EDT Thu May 16 2024

Our stretch of dry weather comes to an end today with a couple of
rounds of light rain showers developing across the area as a
shortwave trough and associated surface low slowly move from MN into
Ontario.

The first batch of rain showers are already moving into the western
UP, and will continue their eastward trek through the rest of the
morning. Showers may become more spotty into the afternoon while the
low tracks into the Arrowhead of MN, struggling to move more
eastward of M-95 with weak dynamical support and dry air in place.
However, as the weak cool front sweeps through this evening, and the
nocturnal LLJ becomes directed over the eastern UP, scattered
showers will become more likely across the eastern UP. A few hundred
j/kg of CAPE over the area indicates a potential for some rumbles of
thunder, but confidence is low with soundings not exactly looking
favorable. Rain showers pull out of hte area late tonight, and skies
may clear partially across the western UP.

Otherwise, expect temperatures to climb into the 60s across most of
the area today, while southeast wind gusts increase to around 15mph
for hte afternoon, higher in the Keweenaw. Dewpoints will have a
chance to mix out once again at least across the eastern UP, with RH
there dropping to around 30-35%. Given increasing wind speeds, today
remains worth monitoring for the fire spread potential. Expect lows
ranging in the 40s under partly to mostly cloudy skies tonight.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
Issued at 347 AM EDT Thu May 16 2024

As the low pressure lifts away into northern Ontario Friday, dry
conditions are expected to return to Upper Michigan until Saturday
afternoon/evening, when a cold front brings additional light rainfall
to the area. That being said, expect summer-like conditions this
weekend into early next week as high temperatures soar into the 70s
and 80s in the interior areas. Rainfall looks to return early next
week and looks to continue on and off until near the end of the
extended period. Additional forecast details follow below.

The last of the rain showers lifts away from the far east Friday
morning as the parent low continues into northern Ontario. As this
occurs, warm air advection begins to move in from the southwest with
time. With the clouds clearing out across the land throughout the
daylight hours, we could see some steep lapse rates develop in the
lowest levels of the atmosphere, causing high temperatures to soar
into the 70s across the interior areas and the 60s along the Great
Lakes. In addition, the strong lapse rates may be enough to create
some pop-up showers across the interior west late in the afternoon,
as seen in some of the CAMs. However, I have my doubts on the shower
occurrence Friday afternoon as most of the atmospheric profile is
looking dry, particularly from the surface to the boundary layer as
an inverted-v around 5 kft high takes shape (according to CAMs
soundings). While a secondary shortwave over northern Minnesota
looks to bring rainfall near the Duluth area Friday afternoon and
evening, the moisture needed to sustain any real convection over the
west is too far away to be of any help. Therefore, I`ve limited
rainfall chances over the west to 10% or less Friday afternoon.

As weak ridging rides through the Great Lakes region Friday night
into Saturday, expect dry conditions over the U.P. Friday into
Saturday morning at the very least. While mostly clear skies will
allow radiative cooling across the area, with warm air advection
continuing across the area, temperatures may have a harder time
tanking than if the warm air advection wasn`t occurring.
Nevertheless, I`ve lowered the temperatures a few degrees using a
blend of the NBM10th and NBM, keeping the lows in the low 50s to
upper 40s in the west and mid 40s in the east. Moving into Saturday,
the dry conditions continue through to the early afternoon hours. As
southerly winds pick up, expect the downslope areas near Lake
Superior to get unseasonably warm; thinking that areas along the
Lake Superior shoreline could get into the 80s for a high, with many
areas in the interior west possibly getting into the mid 80s; this,
combined with the antecedent dry conditions and sunny skies could
bring some limited elevated fire weather concerns back across the
area Saturday afternoon, particularly along the downslope areas
near Lake Superior. With winds coming off of Lake Michigan, the
coolest (and most moist) area looks to be along its lakeshore from
Escanaba all the way east of Manistique to even the Bridge; expect
highs to only get into the upper 60s in this area. Once we hit the
mid to late afternoon, rain showers and possibly (30% chance) a few
embedded thunderstorms begin to make their way into the western
U.P.. However, with the daylight ending and the parent shortwave low
causing the convection moving towards Hudson Bay, shower activity
diminishes, with thunder chances looking to altogether vanish by
late in the night as the cold front continues across the rest of the
U.P. from west to east.

More weak high pressure ridging looks to cross the Upper Great Lakes
Sunday as warm air advection once again returns to the area thanks
to a troughing pattern moving from the western U.S. into the central
U.S.. Thus, expect a pretty similar setup to what we see Saturday,
albeit temperatures inland might be a couple of degrees lower and
the lakeshores noticeably cooler as the surface flow will probably
be weak enough to allow the lake breezes to get going. We may see
another limited elevated fire weather day in the interior west
Sunday as min RHs could drop into the mid 20 percents. Precipitation
returns late Sunday night/Monday as the first of multiple shortwaves
moves into our area.

Multiple shortwaves encroach on our neck of the woods early next
week as the troughing pattern moving from the central U.S. eastwards
keeps sending shortwaves from the Southern Plains up our way. This
will allow us to receive multiple shots of rainfall throughout the
latter portion of the extended period; we could see a soaking
rainfall from one of the shortwaves should "the cards fall right" so
to speak. However, given the high uncertainty of the forecast, the
probability of this happening is rather low at this time. As the
troughing pattern slowly trudges eastward, expect the temperatures
from Monday through next Thursday to progressively lower each day,
being above normal on Monday to below normal by Thursday. Once the
trough moves through, high pressure ridging moves back over us late
next week.

&&

.AVIATION /12Z TAFS THROUGH 12Z FRIDAY/...
Issued at 718 AM EDT Thu May 16 2024

Light rain showers moving into the western UP this morning will
continue to spread eastward through hte morning and afternoon. VFR
conditions lower to MVFR at IWD by mid-morning, then CMX and SAW
will follow and become MVFR later this afternoon. Will carry a few
hours of IFR at IWD during the afternoon as showers pull out, but
that is low confidence. MVFR restrictions linger into the night at
all terminals, but IWD may begin to scatter out after 06Z.
Meanwhile, east-northeasterly winds will shift to the southeast, but
will remain under the 12 kt threshold. And, IWD will see a shift to
southwesterly overnight.

&&

.MARINE...
Issued at 347 AM EDT Thu May 16 2024

Light winds of generally 20 knots or less continue today through
this weekend into early next week as a cold front brings some
showers and maybe (15% chance) an embedded thunderstorm or two this
evening through tonight. Thunder chances return Friday night over
the far western lake near Duluth as a low lifts through northern
Minnesota. As the cold front of the low moves eastward Saturday and
Saturday night, expect the shower and thunderstorm chances to travel
east with it, with the chances decreasing with time after the sun
sets. Thunder and shower chances return Monday as the first of
multiple shortwave lows move across the Upper Great Lakes region.

&&

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

&&

$$

SHORT TERM...LC
LONG TERM...TAP
AVIATION...LC
MARINE...TAP