000
FXUS63 KAPX 240406
AFDAPX

Area Forecast Discussion
National Weather Service Gaylord MI
1206 AM EDT Sat Jun 24 2017

.UPDATE...
Issued at 922 PM EDT Fri Jun 23 2017

Band of mid-cloud working its way out of eastern upper and into
northern lower MI this evening. Even a spot of associated virga
near Beaver Isl. This is occurring ahead of a pair of vort maxes
pivoting away from eastern Superior and toward southern Lake MI.
Have increased cloud cover somewhat for the start of the night in
response.

Otherwise, things are and will remain quiet on the sensible wx
front. No major changes to min temps.

Hydro: calls to Gladwin Co still indicate lingering flooding
issues in the south end of that county, including some closed
roads. However, things have been improving over the last six hours
or so. Barring new/unexpected info, plan on expiring the areal
flood warning for Gladwin Co at 11 pm.

&&

.NEAR TERM...(Tonight through Saturday)
Issued at 248 PM EDT Fri Jun 23 2017

High impact weather potential: Maybe a rumble of thunder in interior
eastern upper into early evening? Slightly better chance at some
isolated thunderstorms tomorrow afternoon. Severe weather not
anticipated. Widespread flooding still ongoing in srn Gladwin county.

Pattern synopsis and forecast:

Upper troughing trying to slide in from the NW this afternoon, with
weak vorticity swinging up through the WSW flow aloft, which has
helped keep some higher level cloud passing by over nrn Michigan.
Meanwhile the lower clouds have continued to scour out, with some
overall drier air seen on latest satellite imagery continuing to
wedge into the NW CWA. The cold front that crossed us last night and
this morning, was now in SE lower Michigan. There have been some
lingering relatively high sfc td`s and BL weak convergence/lake
breeze tendencies that have allowed for isolated showers in NE
lower, as well as in far eastern Chip/Mack counties of eastern
upper. Meanwhile, cooler air aloft with steeper lapse rates ahead of
shortwave troughing was slowly making an eastward progress. There is
some added moisture back behind the wedge of drier air, which hasn`t
fired off any showers in lake breeze convergence in south central
upper Michigan or western sections of Mackinac county just yet.
Temps were generally in the low to mid 70s and the air mass is
slowly getting less humid.

For the remainder of the afternoon and possibly early evening, the
pattern is there for isolated showers to develop across more of
interior upper Michigan. A lack of instability, MLCAPES not even 500
j/kg, likely to keep thunder at bay. Severe weather certainly not
expected. Continued mixing over the next few hours also ought to
more efficiently bring down those sfc dew points to make things less
humid going into tonight. Loss of heating will end any shower
activity that does develop with mostly clear skies through the night
and Saturday morning. Not really expecting any fog, unless we do not
mix out that BL much more heading through afternoon. Then it would
likely just be patchy anyway. Wind speeds Saturday afternoon will be
rather marginal for good lake breeze convergence to develop, but it
will certainly be hugging the shorelines more, especially in
Mackinac county and NE lower. Meanwhile additional weak vorticity
will sweep into the region, which may help in developing isolated to
scattered showers with only a handful of thunderstorms, again,
instability after modifying soundings reveal up to 500 j/kg. Nothing
major. Can`t tie all shower activity to just lake breeze convergence
areas, especially with a bigger shortwave arriving into the srn
lakes in the afternoon. Most of it will likely be there, but had to
keep some small chance in pretty much any spot in nrn Michigan.

Highs in the middle 60s to lower 70s tomorrow with cooler air and
likely more diurnally driven clouds. Lows tonight in the low to mid
50s.

&&

.SHORT TERM...(Saturday night through Monday)
Issued at 248 PM EDT Fri Jun 23 2017

...Below normal temperatures with showers and a few storms...

High Impact Weather Potential...A few (largely) non-severe
thunderstorms this weekend into early next week.

Pattern Synopsis/Forecast...Upper level troughiness in the process
of deepening across the upper Midwest/Great lakes region...driven
along by fairly strong short wave energy crossing the northern
lakes. Cold front has pushed through much of lower Michigan with
cooler/drier air beginning to make inroads into the region. Larger
scale troughiness will continue to deepen through the Great Lakes
and into the Midwest/Ohio Valley through the upcoming weekend into
early next week setting the stage for another period of below normal
temperatures and instability showers.

Primary Forecast Concerns...Minimal. Secondary piece of short wave
energy and weak-ish surface low over British Columbia today will
slide down into the region Saturday night into Sunday. Enough cool
air aloft/modest instability (even into the nighttime hours) and QG-
forcing for ascent with this system to carry showers for all areas
Saturday night. Sct-numerous showers and the chance for
afternoon/early evening thunderstorms for Sunday into Monday as
core of coldest air aloft (now around -24C at 500 MB) slides
overhead. Severe threat still appears minimal although with low wet-
bulb zero heights (around 6K feet)...pulse hail producers with
the strongest updrafts will be a concern.

Otherwise...another stretch of below normal temperatures through the
early part of next week...with readings a good 5 to 10 degrees below
normal.

.LONG TERM...(Monday night through Friday)
Issued at 248 PM EDT Fri Jun 23 2017

High impact weather potential: Chance of thunderstorms at various
times Wednesday through Friday.

Fairly progressive pattern looks to be on tap for the majority of
next week with ridging aloft and surface high pressure
characterizing the start of the period Monday night into Tuesday.
Guidance continues to focus on a several developing areas of low
pressure across the central/northern plains during the middle to end
of next week, ultimately renewing shower and thunderstorm chances
locally as early as Wednesday through the end of the forecast
period. Plenty of uncertainties remain at this juncture, but
confidence is growing in periods of wet weather returning during the
second half of next week across northern Michigan.

&&

.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
Issued at 1159 PM EDT Fri Jun 23 2017

VFR. Sct showers/isolated t-storms Sat afternoon/evening.

Cold front is downstream of MI, crossing the eastern lakes this
evening. Cooler/drier air is entering the region on nw-erly
breezes. VFR conditions will prevail. Cooler air also spills in
aloft on Saturday, resulting in enough instability to produce some
showers/t-storms by afternoon. Best chance for this will be in ne
lower MI (APN) where VCSH is mentioned.

W to nw breezes thru the forecast.

&&

.MARINE...
Issued at 248 PM EDT Fri Jun 23 2017

Gradient winds and waves not expected to be of any issue over the
next several days. An overall west/NW direction to the winds, with
lake breeze tendencies and isolated to scattered showers and a few
storms during the afternoons and early evenings.


&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&

$$

UPDATE...JZ
NEAR TERM...SMD
SHORT TERM...TBA
LONG TERM...MJG
AVIATION...JZ
MARINE...SMD