091
FXUS63 KAPX 061114
AFDAPX

Area Forecast Discussion
National Weather Service Gaylord MI
714 AM EDT Sat Jul 6 2024

.KEY MESSAGES...

- Isolated to scattered pop-up showers and storms today.

- Rain/storms possible Sunday afternoon, and especially Monday
  into Tuesday.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 349 AM EDT Sat Jul 6 2024

Pattern Synopsis:

Longwave troughing will remain draped across most of the northern
CONUS through the duration of the forcast period. An embedded
shortwave will work east of the region this morning as subtle
ridging slides overhead later this afternoon and evening. In turn,
broad low pressure will also depart east underneath favorable
forcing aloft with the aforementioned shortwave while
high pressure settles in later tonight into Sunday.

Forecast Details:

Isolated to scattered pop-up showers and storms today -- A few light
showers may persist across parts of northern Michigan this morning,
along with low clouds and patchy fog development. The main focus
will be later this morning into this evening where isolated to
scattered pop-up showers and storms will be possible. Despite
heights gradually rising through the day as aforementioned shortwave
troughing exits, enough support in the vicinity of the surface
cyclone should exist to kick off at least a few showers/storms --
with the best chances coming along and east of I-75, especially near
Lake Huron/Saginaw Bay. Forecast soundings display a few hundred
joules of MLCAPE with a subsidence inversion around 600mb. Very weak
flow from the surface to 500mb will help keep any activity
disorganized, and aforementioned limited buoyancy will struggle to
support any stronger storms. Activity should diminish this evening
as diurnal heating ceases and high pressure begins to work into the
Great Lakes. Highs in the 70s are anticipated today with overnight
lows in the low to mid 50s for most areas.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
Issued at 349 AM EDT Sat Jul 6 2024

PATTERN SYNOPSIS/FORECAST:

Broad troughing aloft overtaking the bulk of the northern
CONUS...with a nice upper low swirling down into eastern MT
attm...and punch of PV energy lifting out of the Upper Great Lakes.
Attendant occluded surface low with this latter feature over central
MI...with warm front extending largely eastward into New
England...and a surface cold front draping back into central TX.
Bulk of the deepest moisture (pwats greater than 1.5 inches) along
and south of this latter BCZ over the southern US. Shortwave ridging
aloft just to our northwest...with cooler air at 850mb beneath this.
Meanwhile, some theta-e advection from Ontario/Quebec into the Upper
Great Lakes north of the surface low. Low level moisture still
hanging on over the Great Lakes tonight, evidenced by low ceilings
and fog over the area, given nebulous flow in the wake of abundant
rainfall (some areas received 1-2 inches of rain in under an hour
last evening!).

Upper disturbance will be slow to rotate out today...with a bit of
shortwave ridging trying to slip into the region late in the day,
leading to some fog potential tonight into Sunday morning.
However...will be watching additional energy dig into the Upper
Midwest already going into Sunday, bringing warm advection and
potential for attendant activity into the Upper Great Lakes,
especially during the afternoon. Attm...appears this upstream energy
will stall for a time over the central US, leaving us in
southwesterly flow as Beryl makes landfall along the western Gulf
Coast...eventually attempting to slip in going into Tuesday as the
southern extent of this BCZ tries to grab onto Beryl. Some
uncertainty in how this happens -- whether Beryl will be quicker to
eject northeastward along the boundary going into midweek next week,
or whether it will just barely miss the proverbial fingers of the
northern stream trough and have to hang out in the southern US for a
bit longer. For now...does appear that a breakdown of the upstream
pattern will ultimately keep things in motion going into
midweek...with ridging trying to spread eastward over the central
continent going into mid/late week...which could keep things a
little more unsettled here in the Upper Midwest if it comes to
fruition (as well as lead to a potential warming trend). A lot of
details to sort out between now and then, though...particularly with
the tropical system in play. Stay tuned.

Primary Forecast Concerns:

Rain/storms possible Sunday afternoon and especially Monday into
Tuesday...

Sunday afternoon...think it will be another one of those popcorn
shower/storm days. Not necessarily the greatest setup, particularly
noting that model soundings suggest some mid-level layers could
preclude better updraft development...but do think it`ll be another
day where we`ll need to keep eyes to the skies, especially if
outdoor plans are had...even if only to stay dry. Do think we may
need to keep an eye out for some showers to slip in from the west on
warm advection late in the day into Sunday night, though not
expecting much of anything impressive by any means attm. Best
potential for anything to pop (or try to pop) would likely be along
the lake breezes, particularly the Lake Huron lake breeze, where
convergence would be maximized with general (albeit weak)
southwesterly background flow.

Monday...better moisture and subsequent instability enter the
region, along with slightly better deep-layer shear...suggesting
that storm potential will be greater than Sunday...and some storms
could attempt to become stronger. A bit of PV slipping over the
region Monday could help the cause of storms, as it could provide
additional forcing. Further...this could focus storm development,
which, given the aforementioned increasing moisture (pwats
approaching or exceeding 1.5 inches again). Noting that some storms
yesterday ended up going every which way based on outflow
boundaries...and also ended up a little bit slower moving in some
cases, do think we have cause for some localized heavy rain concerns
again (particularly noting that some localized areas under the slow
moving cells produced upwards of 2 inches of rain in less than a
half hour... and this with pwats closer to 1 inch per our
morning/evening soundings). Will have to see if this idea of better
focused/more persistent and/or slow-moving storms actually comes to
fruition...but certainly not impossible that some localized areas
could end up with over an inch of additional rainfall
Monday...particularly if the pattern across the northern CONUS
trends slower, depending on how it reacts/interacts with Beryl
coming onshore near Texas. Another round of storms appears possible
again Tuesday as another wave slips through the region...though
details not very clear attm, again, at least in part related to
Beryl.

&&

.AVIATION /12Z TAFS THROUGH 12Z SUNDAY/...
Issued at 713 AM EDT Sat Jul 6 2024

LIFR/IFR CIGs are expected to linger for another hour or two across
northern Michigan before they begin to lift through the morning
hours. Dense fog across -- primarily across the eastern U.P. -- will
also begin to dissipate over the next several hours as diurnal
heating increases. Flight conditions look to improve to VFR by late
morning/early afternoon for most locations. Mainly light
north/northwest winds between 5-10 kts are anticipated today before
going calm tonight. With clearing cloud cover, efficient radiational
cooling will support patchy FG/BR development again tonight.
Confidence is highest at MBL and CIU, where it has been included in
the TAFs at this time.

&&

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

&&

$$

SHORT TERM...DJC
LONG TERM...FEF
AVIATION...DJC