863
FXUS63 KAPX 291727
AFDAPX

Area Forecast Discussion
National Weather Service Gaylord MI
127 PM EDT Sun Jun 29 2025

.KEY MESSAGES...

- Shower chances this morning precede storm chances later this
  afternoon.

- Multiple rounds of storms expected Sunday night through Monday
  with localized heavy rainfall being the primary threat.

- Largely dry weather prevails through Thursday.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 230 AM EDT Sun Jun 29 2025

Current surface analysis showcases broad area of surface high
pressure traversing over lower Michigan, keeping things dry and
stable for the time being. Decaying surface low pressure moving east
of Val-D`or, Quebec, with attendant stationary boundary draped in a
u-shape around the Great Lakes, stretching south from Montreal to
Pittsburgh to Muncie, IN before turning northwest toward Rockford,
IL and into central Minnesota. Parent surface low pressure just
north of Winnipeg currently driving ample forcing where instability
is currently maximized over South Dakota and Minnesota, driving
quite the convective complex through the Twin Cities area, which
will move eastward toward us... but into an increasingly hostile
environment, which should result in the decay of these storms as
they move into the area, with likely just an embedded mesolow and
outflow boundary in its wake. Increasing warm advection will force
the stationary frontal boundary north and east (as a warm front) to
put us in the warm sector with time on Sunday as the surface low and
associated NE to SW oriented cold frontal boundary work closer,
resulting in increasing shower and storm chances into Monday as
increasingly warm and humid air is drawn into northern Michigan.

Forecast Details:

Anticipating the rest of tonight to remain on the dry side.
Aforementioned complex of storms over the western Corn Belt will
decay as it passes through... minimal fanfare outside of a shower or
two this morning as thermodynamic support plummets from west to
east. In the wake of this passage, anticipating temperatures to
spike well into the 80s, perhaps touching 90 in places, as dewpoints
surge into the 60s. Lapse rates are not overly steep, but may just
enough for some surface based instability to develop if the
convective leftovers from the decaying complex early this morning
can be overcome in a timely manner. CAMs are initiating scattered
convection over the area this afternoon, and with convective temps
generally in the low-to-mid 80s, we should be plenty warm to do
that. Issue with this afternoon`s storm coverage will be an overall
lack of shear, which means that storms will probably struggle to
grow upscale and be pulse dominant. Suppose a stronger gust or two is
possible in any collapsing updrafts, but with PWATs surging into the
1.2 to 1.5 range, coupled with slow storm motions, it`s a recipe for
hyper-localized downpours where some significant rainfall may be
realized. Best chances for this in the afternoon will be across
northeast lower, where better lake breeze convergence and potential
overlapping outflow boundary influences will be strongest... thus
this will be where highest PoPs are retained through day today.

Most guidance is suggesting a break in the action Sunday evening
into the overnight as diurnal instability fades with loss of daytime
heating. Considering closer proximity to better forcing, suppose the
best overall rain chances Sunday night favor NW lower into the
eastern Yoop. Certainly will be a warm and muggy one Sunday night,
with lows in the mid 60s to near 70. Better forcing will be slow to
move into the area, a trend that has been quite noticeable in latest
guidance. With flow becoming less normal to the front, its
advancement eastward will be a slow one... which could put the area
into a longer and even more favorable window for additional storm
development into Monday as highs build back into the mid to upper
80s (upper 70s to near 80 along Lake Michigan and into the eastern
Yoop). As stated by previous forecaster, PWATs holding steady from
1.4 to 1.8 will likely lead to the greater threat being heavier
rainfall outbursts. Weaker shear (20 to 30kts bulk shear) likely
supports more of an outflow driven multicellular mode, with an
outside shot at training updraft potential. Will have to see how
upstream convection influences Monday, but this certainly looks like
impressive rainfall amounts are on the table in places if we can
fully utilize this thermodynamic profile. As far as severe potential
goes for Monday, limited shear will somewhat suppress severe
potential, with gusty winds still holding as the primary concern,
and perhaps some small hail. More details to come in the ensuing
forecast cycles.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
Issued at 230 AM EDT Sun Jun 29 2025

Following the passage of the cold frontal boundary Monday evening,
drier air builds with cyclonic dry slot ushering dry conditions for
Tuesday... with much more seasonable temperatures in the upper 70s
to mid 80s. Quick moving shortwave will zip through WEdnesday,
dragging a moisture starved front through the area later in the day.
Suppose this could bring an afternoon shower or rumble of thunder,
but nothing sticks out pointing to widespread activity. Cooler air
looks to build Thursday in the wake of this passage. An early look
at the 4th of July weekend shows that there is potential for another
active pattern to emerge with shower and thunder chances,
accompanied with a warmer and more humid feel. Certainly more
details to come as we work our way closer to the big holiday
weekend... but for those getting an early start on the festivities
in the Northwoods this week, anticipating minimal impacts through
the weekdays Tuesday and beyond.

&&

.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 127 PM EDT Sun Jun 29 2025

Mainly VFR conditions with perhaps some MVFR mixed in at times
for the period. Showers with isolated storm chances arrive
around midnight tonight and progress west to east. Some
visibilities may be reduced in any heavier showers/ storms,
especailly CIU. Shower/ storm confidence in coverage is low,
with a weakening trend noticed in guidance. Sustained southwest
winds 5-10 knots with occasional gusts 15-20 knots will decrease
through the evening, becoming light overnight. Winds gain a
more westerly component (WSW), towards the end of the period.

&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...None.
MARINE...None.

&&

$$

SHORT TERM...HAD
LONG TERM...HAD
AVIATION...NSC