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fxus63 kapx 220619 

Area forecast discussion
National Weather Service Gaylord Michigan
219 am EDT sun Sep 22 2019

Near term...(today through tonight)
issued at 219 am EDT sun Sep 22 2019

..periods of showers and a few thunderstorms today and tonight...

High impact weather potential...showers and thunderstorms possibly
producing heavy rainfall thru tonight. Severe storms are not

Pattern synopsis/forecast...slow-moving cold front remains well
upstream of our area...currently extending from low pressure
centered over western Ontario thru the length of Minnesota into the
Central Plains. Several areas of convection continue to fire along
and ahead of this front...some of which is impacting Michigan.
Plenty of moisture is available for precip production as southerly
winds ahead of the front continue to tap Gulf moisture enhanced by
the remnants of tropical storm Imelda. Very limited instability is
keeping embedded thunder to a minimum...especially with the loss of
any help from diurnal heating overnight. Upstream radars shows an
area of more widespread continuing to develop from SW Iowa into
eastern Nebraska and northern Kansas...serving as a clue of what's
to come.

As we head into today and tonight...cold front will slide into the
western Great Lakes this morning and then further slow/nearly stall
as a wave develops along the front and rides NE thru our County Warning Area over
the next 24 hours. Wave development will boost lift and synoptic
support for precip production...and with plenty of deep Gulf
moisture...see no reason to stray from categorical pops as well as
the potential for some periods of heavy rainfall. 00z apx sounding
showed pwats of 1.7 inches...which matches fairly well with model
estimates of 1-2 inches of quantitative precipitation forecast across portions of northern lower
Michigan thru tonight. Thunder is certainly possible today and
tonight...but instability remains limited and expect this will
continue to keep embedded thunder to a minimum. We may see a boost
in thunder during peak heating...but still think this will not
result in any severe storms.

After several warm and humid days of above normal temps...thick
cloud cover and widespread precip will hold temps in the low to mid
70s throughout the day. Cold air advection will begin tonight immediately behind
the cold front...with overnight lows cooling into the 50s.


Short term...(monday through tuesday)
issued at 219 am EDT sun Sep 22 2019

..showers ending Monday, more seasonable weather...

High impact weather potential: minimal

Pattern/synopsis: general troughing exists over The Rockies
currently, with a shortwave rotating through The Four Corners
region. This wave swings up through the Central Plains into the
upper Mississippi on its way toward US on Sunday. This induces a
surface low which rides up a pre-existing front toward lower
Michigan. By Monday morning this weak surface low should be
somewhere over Lake Huron. It will still be working with some decent
moisture, with pwats remaining aoa 1.0" especially east of i75.
Showers will linger off and on through the day, helped out by wrap-
around moisture as the system pulls off to the east. The upper
levels dry out fairly quickly through the morning hours, but lower
levels of the atmosphere are slower to do so. Drier air eventually
works its way into the region late Monday as surface high pressure
slides to our south. Shower threat fully diminishes overnight.
Temperature-wise we won't rebound very much with lingering rain,
thick cloud cover, and continued cold air advection. Highs look to be only in the
60s. The deepening low over Huron will also cause gusty northwest
winds across the area as it pulls off to the northeast. There's
still uncertainty regarding exact placement and strength of the low
Monday morning, so wind speed confidence may increase in the next 24
hours or so. On Tuesday shortwave ridging passes quickly overhead,
as a surface ridge axis crosses at the surface. The surface high
treking through the Ohio Valley will lead to a mild and dry day with
warm air advection occurring around the backside. Clouds will likely clear out
sometime Tuesday afternoon (outside of some spotty cu) before the
next surge of moisture moves in through the night out ahead of the
next system in The Rockies. Tuesday will be a bit warmer than
Monday, with highs near 70.


Long term...(tuesday night through saturday)
issued at 219 am EDT sun Sep 22 2019

High impact weather potential: minimal

The next system manifests itself as a low moving out of the northern
plains into Ontario on Wednesday. The associated cold front will
bring a renewed threat of showers (and possibly thunder?) Wednesday
into Thursday. Above normal temperatures Wednesday will be followed
by a very brief cool-down (only to near normal) Thursday behind the
front. More showers and another rebound toward warmer temperatures
expected as we head into next weekend. All guidance suggests another
period of unusually warm early Fall weather for the weekend into
early next week.


Aviation...(for the 06z tafs through 06z Sunday night)
issued at 1141 PM EDT Sat Sep 21 2019

Scattered showers and possibly a few thunderstorms will continue
to move through northern lower Michigan tonight with conditions
moving toward MVFR everywhere across northern lower Michigan.
Steady rain and thunderstorms will overspread the region Sunday
morning and bring IFR weather to the terminal sites through the
day. Some heavy rainfall is possible.

Periodic gustier south to southwest winds continue through
tonight before diminishing through the day Sunday.


issued at 219 am EDT sun Sep 22 2019

Winds and waves will continue to reach Small Craft Advisory criteria within all of
our nearshore areas today into early evening thanks to gusty
southerly winds ahead of an approaching cold front. Widespread
showers and a few embedded thunderstorms will develop today as deep
Gulf moisture surges northward ahead of this front...with heavy rain


Apx watches/warnings/advisories...
LH...Small Craft Advisory until 8 PM EDT this evening for lhz345>349.
Lm...Small Craft Advisory until 8 PM EDT this evening for lmz323-341-
Ls...Small Craft Advisory until 8 PM EDT this evening for lsz321-322.


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