123 
FXUS63 KAPX 110219
AFDAPX

Area Forecast Discussion
National Weather Service Gaylord MI
1019 PM EDT Sat Apr 10 2021

.UPDATE...
Issued at 1019 PM EDT Sat Apr 10 2021

Vertically-stacked low pressure remains centered over Illinois
late this evening. Deep moisture surging northward continues to
produce a swath of widespread showers...the northern edge of which
is slowly lifting northward into our CWA. Arrival time of showers
has been rather slow...but appears deep moisture is finally
winning out with most areas south of M-32 now receiving steady
rainfall. Thunder has been hard to come by across our CWA...but
cannot rule out a few rumbles of thunder for our southern CWA over
the next few hours. Have made some minor adjustments to POPs for
the overnight hours. Temps will only drop a few degrees
overnight...with low temps in the mid to upper 40s.

&&

.NEAR TERM...(Through Tonight)
Issued at 308 PM EDT Sat Apr 10 2021

...Widespread showers tonight...

High impact weather potential: Minimal. A few rumbles of thunder 
expected into this evening. Nothing severe anticipated

Pattern synopsis and forecast:

As one area of low pressure exits off into Canada, another begins to 
take shape this afternoon as strong shortwave trough rotates 
northeast across Missouri. In-between these systems is low amplitude 
mid level ridge axis, which is conveniently draped right across 
northern Michigan. The result has been a fairly quiet start to the 
day, with just some clouds spreading across our landscape. Another 
mild mid-April day, with current readings mostly ranging through the 
50s and 60s.

Our break from the rain will definitely not last long as that 
Missouri wave continues to pivot northeast, reaching vicinity 
Illinois/Indiana border by sunrise Sunday. Strong surge of theta-e 
advection and upper level jet support will pivot into our region as 
a result, bringing a round of widespread rain from south to north 
later this afternoon and tonight.

Primary forecast concerns/challenges:

Addressing shower/thunderstorm evolution tonight and attendant 
rainfall amounts.

Details:

Expect band of showers to make steady progress north across the area 
into this evening as surge of deep moisture/theta-e advection does 
the same. Precipitable water values up to and a bit over an inch and 
expected isolated deeper convection (rumbles of thunder) via a few 
hundred joules/kg of elevated cape supports some decent rainfall 
rates at times. Given expected fairly transient progression of most 
organized showers, do not think rainfall totals will get too out of 
hand, perhaps up to an inch (locally higher) for areas south of M-
72. Moisture axis thins a bit the further north one goes, so expect 
rainfall totals to do the same. Not expecting any severe weather, 
given such limited and elevated cape profiles. Dry slot works 
steadily north, reaching our southern zones toward morning, ending 
the better rains for those areas in the process. Another mild night, 
with lows only dropping into the 40s.

&&

.SHORT TERM...(Sunday through Tuesday)
Issued at 308 PM EDT Sat Apr 10 2021

High impact weather potential: None at this time.

A slow moving area of low pressure over the Great Lakes region will 
continue to impact northern Michigan's weather with moisture 
advecting into the forecast area in the warm sector through Sunday 
on south to southeasterly winds. With this system moving very slowly 
north-northeastward, the forecast area remains in the warm sector 
with periods of showers throughout...especially during the afternoon 
hours with diurnal heating. Models continue to agree with this 
stacked system over the Great Lakes region lingering 
overhead...continuing to provide cloudy and wet periods throughout 
the remainder of this forecast period and possibly beyond. The winds 
will once again veer to the southeast as this storm system continues 
it's very slow movement towards the forecast area and becomes gusty 
once again Sunday. Winds finally veer to more northwesterly by late 
Monday as the system finally moves off to our east and ushers in 
some colder temperatures. Temperatures will continue to be well 
above normal for this time of the year...reaching into the upper 50s 
to low 60s Sunday and Monday, with Tuesday being more seasonal, only 
in the upper 40s to low 50s as the colder air is ushered in on the 
northwesterly winds. Lows will drop into the low 30s to near 
40...returning chances of frost to the area by Monday night.

.LONG TERM...(Tuesday night through Saturday)
Issued at 308 PM EDT Sat Apr 10 2021

Long term: High Impact Weather Potential: Minimal.

A rather inconclusive long term forecast is on tap. Models are 
anywhere from cloudy with chances of rain each day to high pressure 
and dry throughout the entire long term period with moisture and 
chances of showers just to our west. Going with the national blend 
at this time in collaboration with our neighbors. Mostly dry 
forecast, but wouldn't be surprised if that changes and we have a 
couple/few periods with some rain chances. Daytime temperatures will 
be in the 50s...while dropping into the low to mid 30s with some 
frost/freeze conditions possible.

&&

.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 700 PM EDT Sat Apr 10 2021

Vertically-stacked low pressure centered over Illinois will slowly
track east thru Indiana tonight into Sunday...reaching Lake Erie
by Sunday evening. Widespread rain showers will continue to spread
northward into Northern Lower Michigan tonight...and will then
diminish to scattered rain showers on Sunday as the deeper
moisture pulls north of Michigan. VFR conditions will slowly drop
to MVFR tonight...and will generally remain MVFR/low VFR on
Sunday. NE winds around 10 to 15 kts will become east late tonight
into Sunday morning...and will then begin to shift to the NW 
Sunday afternoon as the low center begins to shift east of
Michigan.

&&

.MARINE...
Issued at 308 PM EDT Sat Apr 10 2021

Low pressure cutting slowly across Illinois tonight will bring some 
marginal small craft advisory northeast winds to portions of 
northern Lake Michigan, with winds expected to remain below advisory 
levels across the remainder of the nearshore waters. Focus for 
stronger winds centers across northern Lake Huron up into Whitefish 
Bay on Sunday, perhaps bringing some marginal small craft advisory 
conditions to those areas. Widespread showers spread across the 
region from south to north this evening. Although widespread showers 
end early Sunday, expect at least scattered showers to persist right 
into early next work week.

&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...SMALL CRAFT ADVISORY until 8 AM EDT Sunday for LMZ342-344>346.
LS...NONE.
&&

$$

UPDATE...MR
NEAR TERM...MB
SHORT TERM...TL
LONG TERM...TL
AVIATION...MR
MARINE...MB