097
FXUS63 KMQT 131057
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
657 AM EDT Mon May 13 2024

.KEY MESSAGES...

- Dry weather returns today, continuing through Wednesday, then
  showers at times Thursday through the weekend.
- Some limited fire weather concerns are expected for Iron and
  Dickinson counties this afternoon.

&&

.SHORT TERM /THROUGH TODAY/...
Issued at 159 AM EDT Mon May 13 2024

Skies have cleared out behind the cold front this morning as high
pressure ridging builds into the Upper Great Lakes region the rest
of today. This is clearing in the cloud cover is allowing
temperatures to plummet across the area, with some spots (including
the office in Negaunee Township) already dropping down into the 40s.
With the temperatures decreasing throughout the pre-dawn hours,
expect lows to still be in the low 40s across most of the area. The
only exception looks to be around the city of Menominee, where some
stubborn cloud cover could keep lows in the mid to upper 40s.

Mostly sunny skies remain over the area during the daylight hours
today, with weak cold air advection aloft behind the cold front
ceasing by the afternoon hours. With weak northerly flow across our
area today, we could see the Lake Superior lake breeze reach all the
way down to the Lake Michigan shoreline. Thus, there may be a few
northerly wind gusts up to 20 mph at times this afternoon over the
eastern half. In addition, cooler temperatures are expected over the
east half, with highs in the mid to upper 40s near Munising to the
low 60s near the Lake Michigan shoreline. With the lake breeze being
weaker over the western half of the U.P., expect warmer
temperatures, with highs generally getting into the 50s. In the
interior west, where the Lake Superior lake breeze fails to reach,
expect highs in the 60s, with a few spots near the Wisconsin border
flirting with 70. In addition, without the moistening input from the
lake over the area, min RHs are projected to get into the upper 20
percents across Iron and Dickinson counties, creating some elevated
fire weather concerns. However, with the winds being light from the
north/northwest across the interior west this afternoon (10 mph or
less), the elevated fire weather concerns are somewhat limited.
Therefore, no fire weather SPS will be issued for Iron and Dickinson
counties today.

&&

.LONG TERM /TONIGHT THROUGH SUNDAY/...
Issued at 357 AM EDT Mon May 13 2024

Mid-level ridging in central Canada will support sfc high pres over
Hudson Bay for the next few days. This high will extend a ridge s
into the Northern Plains and Upper Mississippi Valley today and then
thru the Upper Great Lakes for Tue/Wed, allowing for dry days thru
Wed. Temps will be on the cool side closer to Lake Superior and
generally around normal well inland. Models have broad agreement on
troffing progressing into the central U.S. heading into the late
week period. This will lead to the next chc of shra during Wed
night/Thu. Thereafter, model spread rapidly increases into and thru
the weekend due to major differences in timing/amplitude of waves
rounding a ridge just off of the W Coast. These differences
translate to a very uncertain progression/amplitude of waves
downstream to the Great Lakes region. For now, it seems that the
pattern should favor somewhat unsettled weather for the Upper Great
Lakes. Whether periodic shra occur over the weekend into early next
week or a more widespread longer duration pcpn event occurs remains
to be seen. Temps during the last half of the week should tilt
toward above normal, but that will depend on the evolution of
shortwaves thru the Upper Great Lakes. Next week, ensembles suggest
temps will generally be on the cool side of normal under fairly
widespread negative height anomalies across a good portion of the
northern half of the Lwr 48.

Beginning tonight thru Tue night, aforementioned sfc high pres will
be ridging s into the Upper Great Lakes region. Fcst soundings
suggest mainly clear nights tonight and Tue night and a mainly sunny
day on Tue. With sfc high pres ridge more firmly over the area Tue
night, Tue night will likely be the cooler night though there may be
some high clouds to contend with. Precipitable water is not
especially low to really enhance the cooling potential. Still, with
precipitable water running 55-70pct of normal, will favor the lower
side of avbl guidance, especially Tue night. Expect min temps
ranging thru the 30s F tonight, coolest interior w half. Tue night
should be a little cooler with mins at traditional interior cold
spots having a better shot at slipping just blo 30F. A gradient
onshore wind enhanced by the lake breeze component on Tue will lead
to cool conditions along Lake Superior. Expect highs in the 40s F
there. Temps will range up to the lwr 60s F well inland interior w
half. Mix down of drier air in the aftn will result in RH falling to
20-30pct interior w half, but lighter winds not gusting above 15mph
will limit fire weather concerns.

Sfc high pres will begin to slip e on Wed, but still a dry day. Mid-
level trof progressing to the central U.S. will lead to some
increase in cloudiness during the day, especially w half. Highs will
range from the 50s F near Lake Superior to well into the 60s F
interior w half.

Low amplitude mid-level trof moving out across the Northern Plains
on Wed will shift toward the Upper Great Lakes on Thu. Shra
associated with this feature should spread into western Upper MI
late Wed night, then progress eastward on Thu. There is fair
agreement that Fri will be a drier day, but not necessarily dry
everywhere all day. Fcst will then reflect broad brush 30-40pct chc
of shra over the weekend. For now, widespread or all day rain is not
expected.

&&

.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 657 AM EDT Mon May 13 2024

VFR conditions continue across the TAF sites as mainly northerly
flow continues over the next 24 hours. While not expected, there is
a 10% chance that some marginal LLWS could be seen over KSAW for an
hour or two tonight.

&&

.MARINE...
Issued at 357 AM EDT Mon May 13 2024

Sfc high pressure over Hudson Bay will extend a ridge south into the
Northern Plains and Upper Mississippi Valley today. The ridge will
drift across the Upper Great Lakes thru Wed. As a result, expect
winds mostly under 20kt, but with some exceptions. NW winds will
gust up to 25kt over eastern Lake Superior today ahead of the ridge.
On Wed, NE winds gusting up to 25kt will be possible over far
western Lake Superior. Winds will continue to be mostly under 20kt
Thu/Fri.

&&

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

&&

$$

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