381
FXUS63 KMQT 081146
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
746 AM EDT Wed May 8 2024

.KEY MESSAGES...

- Rain showers mainly end this morning as the low pressure
  system departs. However, slight chances for light showers
  continue over the west into this afternoon.
- Multiple passing low pressure systems will keep rain chances
  in the forecast into early next week along with thunderstorm
  chances both Sunday and Tuesday.

&&

.SHORT TERM /THROUGH THIS AFTERNOON/...
Issued at 519 AM EDT Wed May 8 2024

Current RAP analysis has the shortwave and sfc low responsible for
the line of showers yesterday and the current comma head of showers
lighting up the radar over the east and Lake Michigan well stacked
over the Mackinac Bridge. As these two features move east today
toward New England, the heavier showers will move east with it this
morning. Additional accumulations this morning are expected between
a few hundreths and 0.3", higher in the east half of Upper MI.
Although the better precip moves out this morning, slight chances
for low impact light showers/drizzle continues throughout the day.
Best chances for precip (~15-20%) are over the east as PWATs show
decent moisture around 0.75" and some weak q-vector convergence
remains. Confidence in timing or exact location of these showers is
low as PoP solutions among the CAMs were not in agreement. Best
consensus was over the western half of the UP earlier in the
afternoon, save for the Keweenaw. Additional accumulations after
sunrise likely will only be a few hundreths at best, so no real
impacts are expected. Any lingering precip should end by this
evening as drier air advects in from the north. With northerly winds
off Lake Superior today, highs near the lake will stay lower in the
upper 40s to mid 50s. The interior and southern half of the UP are
expected to see highs peak in the upper 50s to mid 60s.

&&

.LONG TERM /TONIGHT THROUGH TUESDAY/...
Issued at 452 AM EDT Wed May 8 2024

Periodic rain chances will be common throughout the extended period
as a series of low pressure systems pass through Upper Michigan.
Initially though, the period will start in a bit of a lull as a
Northern Plains closed mid-level low continues to slide
southeastward while opening up and drifting around the Lower
Midwest.  Meanwhile, the associated surface low ahead of it will
drift through the Ohio Valley.  So, what this means for much of the
UP is a dry forecast Wednesday night through Friday morning. Earlier
model runs were originally taking more of a northern track with the
aforementioned disturbance.  But, the southern track has come to
fruition, thus rain chances have been removed from the south and
east from Thursday.  And strengthening subsidence/ridging will keep
the forecast dry through Friday morning.

By Friday afternoon, mid-level ridging will begin to break down as
the next shortwave dives southeast from northern Saskatchewan.  With
an uptick in isentropic ascent after Fri 18Z, rain showers will
overspread the UP from west to east through the evening, quickly
tapering off after Sat 06Z with loss of dynamics. In addition,
will briefly carry thunderstorm mention over the west-southwest
portions of forecast area Friday evening with that sector
falling under the left exit region of a weak upper level jet,
but that is low to moderate confidence at this point.

After some lingering 10-20% rain chances through Saturday afternoon
(central and east) in association with departing shortwave, there
will be a lull in activity Saturday night as brief ridging once
again builds over the UP.  Again though, the dry weather will be
short-lived as focus turns to a series of systems traversing first
northern Manitoba and then southern Saskatchewan/Manitoba.  Showers
and thunderstorms will accompany both systems on Sunday and again
Tuesday.  And, it is still a bit early, but instability and vigorous
cold fronts could be enough to generate some strong thunderstorms
both days.  These will be targets of opportunity to monitor,
especially Tuesday afternoon/evening as high temperatures climb into
the low to mid 70s.

&&

.AVIATION /12Z TAFS THROUGH 12Z THURSDAY/...
Issued at 125 AM EDT Wed May 8 2024

The low pressure system over the eastern UP departs eastward today,
resulting in improving flight conditions. IWD and SAW may see some
patchy fog yet in the next hour or two with light winds and ample
moisture leftover from previous precip. With daytime heating, this
is expected to mix out as cigs gradually improve to VFR. Downslope
northeast flow will keep CMX at VFR throughout the 12Z TAF period.
SAW and IWD also may see some isolated light showers/drizzle this
afternoon. However, mention of afternoon precip was left out of the
TAFs with low confidence in timing or location.

&&

.MARINE...
Issued at 521 AM EDT Wed May 8 2024

Northeast winds of 25 to 30 knots will prevail today and tonight
mainly over western and central portions of Lake Superior.  After
that, despite wind shifts due to multiple low pressure systems,
winds will remain below 20 knots through Sunday.

&&

.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
  Small Craft Advisory from 11 AM EDT /10 AM CDT/ this morning
     to 8 PM EDT /7 PM CDT/ this evening for LSZ240>242.

  Small Craft Advisory from 11 AM this morning to 5 PM EDT this
     afternoon for LSZ243-244.

Lake Michigan...
None.

&&

$$

SHORT TERM...Jablonski
LONG TERM...TDUD
AVIATION...Jablonski
MARINE...TDUD