216
FXUS63 KMQT 042235
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
635 PM EDT Fri Oct 4 2024

.KEY MESSAGES...

- Areas of frost for the interior central and eastern forecast area
  tonight.

- Critical fire weather conditions Saturday across the area due
  to RHs dip into the lower to mid 30s, southerly winds gust up
  to 35 mph, and ongoing drought conditions. See the latest Red
  Flag Warning for additional details.

- Only potential of rainfall over the next 7 days occurs
  Saturday night and Sunday. Widespread, significant rainfall
  not expected, but could see around a quarter to half an inch
  across the area.

- Over the next 2 weeks, there are no signs of a transition to a
  more typical fall pattern that would bring more frequent
  precipitation. Drought conditions are likely to expand and
  deepen over the next 2 weeks with continued fire weather
  concerns on windier days.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 346 PM EDT Fri Oct 4 2024

Water vapor imagery and RAP analysis show a vigorous shortwave trof
moving onshore over BC and Pacific NW. Downstream, ridging is
progressing into s central Canada and the Northern Plains. Closer to
home, a shortwave trof is moving eastward across the Great Lakes
region. With Upper MI on the backside of that trof and under a dry
air mass, it`s been a mainly sunny day across the area. At the sfc,
the upstream mid-level ridge is supporting sfc high pres centered
over central WI. Current temps are in the upper 50s to mid 60s F,
pretty close to the normal high temps for Oct 4th.

A few high based cu and some incoming mainly thin ci clouds from the
wnw will be the rule thru late aftn. So, tonight will begin with
mainly clear skies, and it will stay that way thru the night. Sfc
high pres center will move from ne WI across northern Lwr MI
tonight, supporting lightest winds across s central and eastern
Upper MI. Air mass is not especially dry with precipitable water 60-
70pct or normal, but that will still enhance radiational cooling.
Favored the lower side of guidance, which puts min temps into the
low and mid 30s F in that area with areas of frost to develop. Frost
advy will be will be issued from Iron/Marquette counties eastward.
Frost will occur well inland from Lake Superior as developing sw
gradient wind will be enhanced by the land breeze, helping to hold
temps up closer to the lake. Temps will range up into the 40s F in
that area and thru nw and far western Upper MI.

&&

.LONG TERM /SATURDAY THROUGH FRIDAY/...
Issued at 450 PM EDT Fri Oct 4 2024

     Critical Fire Weather Conditions Saturday Afternoon...

The first half of the extended period is very active, with a
low- level jet and dry air bringing critical fire weather
conditions to the area Saturday; southerly wind gusts could get
as high as 35 to 45 mph in the downslope areas near Lake
Superior. Then Saturday night, a line of showers and
thunderstorms looks to move through along a cold front. While
the rainfall will wet the ground, it won`t slow our degradation
into worsening drought conditions next week. In addition, there
may be a strong thunderstorm or two that develops along the cold
front, which may bring some hail and additional strong winds to
the surface. Behind the cold front, some light lake- effect
rain showers looks to impact the northwest wind belts,
particularly over the east, Sunday into possibly Monday.
Afterwards, more dry and abnormally warm weather returns as we
head into the rest of next week.

Saturday will be an eventful weather day across the Upper Peninsula.
For starters, as a strengthening low pressure races across the
Canadian Prairies, warm air advection and an impressive 60+ kt 850
mb low-level jet move into our neck-of-the-woods. These strong winds
aloft will somewhat be mixed to the surface, bringing strong
southerly winds up to 35 mph to the surface by the early afternoon,
with downsloping near Lake Superior possibly getting gusts up to 45
mph at times by the mid to late afternoon. In addition, the warm air
advection will allow temperatures to get into the mid 60s to lower
70s Saturday, with the warmest temperatures expected over the west
in the downslope areas along Lake Superior. However, given that the
warm air advection will be working to bring moisture to the area
Saturday ahead of the low`s cold front, critical fire weather
conditions will be somewhat limited to a few hours Saturday
afternoon as RHs improve from the lower to mid 30 percents to 50+
percent late in the day. There does seem to be a few hours though
(mainly in the downslope areas along Lake Superior, the Keweenaw
Peninsula, and the east). After consultation with our fire weather
partners, we have decided to issue a Red Flag Warning for the U.P.
given the drought conditions and windy conditions. However, as
moisture improves from west to east throughout the afternoon and
evening hours, expect to likewise see an end to the critical fire
weather conditions from west to east Saturday.

Heading into Saturday night, the cold front arrives, bringing rain
showers and a few embedded thunderstorms with it. While severe
weather is not expected due to the lack of CAPE and low lapse rates
in the lower-levels of the atmosphere, there is still a possibility
that we may see some sub-severe hail and gusty, erratic winds at the
surface as lapse rates and CAPE improves greatly in the mid to upper
levels (the European ensemble also shows anomalously high shearing
throughout the atmospheric profile). While a soaking rainfall is not
expected, we could see moderate rain rates along the cold front via
the embedded rain showers and elevated thunderstorms; the latest run
of the HREF shows up to a 20% chance (of 0.50 inches of rain in any
given hour) of this occurring in isolated spots across Upper
Michigan Saturday night. Skies clear behind the cold front late
Saturday night. If you`re still up or are just waking up, you may
catch a glimpse of the Northern Lights early Sunday morning!

Expect Sunday to be a cooler and windy day across Upper Michigan.
With strong cold air advection continuing across the Upper
Peninsula, west to northwest winds up to 30 mph is expected across
the area. In addition, we may see Wind Advisory criteria being met
over the Keweenaw as winds could frequently gust up to 45 mph or
higher (the LREF shows around a 50% chance of occurrence). Otherwise,
due to delta-Ts over Lake Superior getting to 15 C, we will likely
(50 to 60% chance) see light lake-effect rain showers over the
northwest wind belts Sunday into Sunday evening. While not much
liquid is expected with these lake-effect rain showers, they will
help to bring a few hundreths back into the soil, particularly over
the eastern U.P. where the fetch over Lake Superior (and thus the
moisture flux) will be greatest. As ridging tries to fight its way
back over us next week, expect the light lake-effect rainfall to
progressively end over the northwest wind belts from west to east
Sunday evening through Monday. Although one more shot of cold air
advection will reinvigorate the light lake-effect rainfall over the
eastern U.P. Monday, expect the last of the rain showers to end by
Monday evening/Tuesday morning. Expect high temperatures to range
from the mid 50s to mid 60s Sunday and Monday, and for lows to range
from the 30s to around 40 in the interior areas (in the 40s along
the Great Lakes); some areas of frost are possible over the interior
west Sunday night and Monday morning.

Moving into the middle of next week, expect a return of dry and
abnormally warm conditions, with highs typically being in the 60s
and lows in the 30s and 40s. Given the sun and lack of precipitation
next week, expect drought conditions to worsen across the area. This
may increase fire weather concerns as we head towards the latter
half of next week.

&&

.AVIATION /00Z TAFS THROUGH 00Z SUNDAY/...
Issued at 635 PM EDT Fri Oct 4 2024

With a dry air mass dominating, VFR will prevail thru this fcst
period at IWD/CMX/SAW. Tightening pressure gradient will lead to
gusty southerly winds on Sat with gusts to 25-30kt at all terminals
by late morning. Nocturnal inversion will result in LLWS at IWD late
tonight/early Sat before mixing depth increases and sfc winds become
gusty.

&&

.MARINE...
Issued at 450 PM EDT Fri Oct 4 2024

Southwest winds of 20 to 25 knots over the western lake this
afternoon eventually weakens to around 20 knots this evening as
ridging peaks overtop the Upper Great Lakes. However, beginning
Saturday morning, expect winds to pick-up from the south as a
strengthening low pressure system moving east over the Canadian
Prairies brings a low-level jet of 60+ knots across our area. This
will allow southerly winds to gust up to gales 35 knots across most
of the lake (save the far west where winds will only get up to 30
knots). However, with localized convergence occurring just east of
the tip of the Keweenaw, we could see high-end gales up to 45 knots
over the central lake Saturday afternoon into evening. Once the cold
front passes through Saturday evening, expect the winds to veer to
the west and initially slacken to around 30 knots. However, as cold
air advection continues across the lake Saturday night into Sunday,
expect west to northwest winds to increase to gales of 35 to 40
knots across the lake, with a few high-end gale-force gusts up to 45
knots being possible Sunday near the Keweenaw. As the cold air
advection weakens Sunday evening, expect the winds to progressively
weaken to 20 to 25 knots by Monday morning. However, another shot of
cold air advection looks to move over the area Monday, increasing
northwest winds back up to 20 to 30 knots across the lake. As
ridging fights its way into the Upper Great Lakes early this week,
expect the winds to die down to 20 knots or less by Monday night and
to remain that way throughout the rest of next week.

Outside of the gales, some elevated thunderstorms could be seen
along the cold front Saturday evening through night; the
thunderstorms could bring a few strong winds and some hail to the
water`s surface.

&&

.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
  Red Flag Warning from noon EDT /11 AM CDT/ to 5 PM EDT /4 PM
     CDT/ Saturday for MIZ001>005-009>013-084.

  Frost Advisory from 2 AM EDT /1 AM CDT/ to 9 AM EDT /8 AM CDT/
     Saturday for MIZ005>007-010>014-085.

  Red Flag Warning from noon to 8 PM EDT Saturday for MIZ006-007-
     014-085>088-095>097.

Lake Superior...
  Gale Warning from 2 AM EDT /1 AM CDT/ to 8 PM EDT /7 PM CDT/
     Sunday for LSZ162-240-241.

  Gale Warning from noon Saturday to midnight EDT Sunday night
     for LSZ242-263.

  Gale Warning from noon Saturday to 2 AM EDT Monday for
     LSZ243>250-264>266.

  Gale Warning from 5 PM Saturday to 2 AM EDT Monday for LSZ251-
     267.

Lake Michigan...
  Gale Warning from 5 PM Saturday to 2 AM EDT Sunday for LMZ221-
     248-250.

&&

$$

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