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fxus63 kapx 210726 

Area forecast discussion
National Weather Service Gaylord Michigan
226 am EST Thu Nov 21 2019

Near term...(today through tonight)
issued at 224 am EST Thu Nov 21 2019

Impactful weather: minimal.

Pattern synopsis and forecast:

A shortwave trough and associated sfc low pressure were in The Heart
of the country early this morning, while mid level ridging was over
nrn Michigan. There was a sfc cold front extending southward from
the low, while a quasi-stationary boundary extended NE through
Ontario. This was ahead of another shortwave trough from central
Canada down through Montana. Two main areas of precipitation were ongoing
upstream with these features. One was pushing through The Arrowhead
of Minnesota and Western Lake Superior, which was a mix of rain and snow.
The other was a larger expanse of rain pressing through the mid and
upper Mississippi Valley and Midwest. Both were being driven strong
low to mid level warm air advection, pockets of upper jet divergence and DPVA. Here
in nrn mi, thickening higher level clouds were the main theme, along
with retreating lower level clouds from SW to NE. No precipitation
was occurring, but that will change...

The aforementioned shortwave and sfc low pressure in The Heart
country will race through the western and nrn Great Lakes today,
which will be followed by a cold front and the nrn stream Canadian
shortwave tonight. Strong low to mid level warm air advection and increasing DPVA
will join with The Pockets of upper jet divergence, to result in
strengthening deep layer -divq as the system blows through nrn Michigan.
800 mb temperatures will rise to +2c in eastern upper to as high as +7c
in the srn County Warning Area prior to the onset of rain that will overspread all
of nrn Michigan today. Sfc temperatures will be above freezing as
well, so no mixed precipitation is expected.

The rain tapers off this evening, with cold air advection setting in via gusty northwest
winds of roughly 25 to 35 mph. The combination of the Canadian
shortwave and 800 mb temperatures falling to -6c to -10c, will bring
more than enough Overlake instability, to fire off developing lake
effect rain showers, which will gradually changeover to snow showers
through the night. This is quite the quick-hitting lake effect
event, and the resident time of deep moisture with the wave is
small. Any lake effect weakens substantially overnight as the
atmosphere dries out. Thus, total snowfall amounts will be less than
impressive, with no more than an inch in the most favored northwest flow
regimes. This will be in western Chippewa County and the interior
higher terrain of nrn lower, between M-68 and M-72.

Highs today will be in the low to mid 40s, with lows mainly in the
mid to upper 20s.


Short term...(friday through saturday)
issued at 224 am EST Thu Nov 21 2019

High impact weather potential: none

We begin a transition to showery precipitation and a cooler
air mass producing light snow showers with wrap around moisture from
the departing storm system mentioned in the previous forecast
discussion above and marginal lake effect parameters perhaps
enhancing this precipitation a bit over portions of northwest lower
and eastern upper through Friday morning. High pressure and drier
air then builds into the forecast area behind this departing
storm system Friday afternoon...although there is a bit of lingering
moisture and 850mb temperatures of around -10c that could continue
some light lake effect snow showers for portions of the forecast
area...mainly northwest lower. High pressure continues to build into
the Great Lakes region from the Central Plains and will produce a
break from precipitation and mostly clear to partly cloudy skies
Friday night through the remainder of the period except for Sunday
afternoon/evening for eastern upper where a tail end of a weak cold
front associated from a low pressure system over Hudson Bay will
increase cloudiness and produce slight chances of rain/snow. High
temperatures will be in the low 30s Friday with the cooler
air filtering in behind the aforementioned departing system.
Temperatures will rebound a bit...reaching into the upper 30s with
some sunshine Saturday and Sunday. Low temperatures will generally
be in the low to mid 20s. Gusty northwest winds will back to
westerly Friday afternoon and lessen in intensity and remain so
through the remainder of the period.


Long term...(saturday night through wednesday)
issued at 224 am EST Thu Nov 21 2019

High impact weather...mixed precipitation possible toward mid-week.

Fairly quiet weather is expected on Sunday night with nearly zonal
flow aloft. Extended models then differ on what happens after that
leaving lots of uncertainty. Chances are that the quiet weather will
extend into Monday. A stronger system may or may not impact the area
Tuesday into Wednesday but there is way too much uncertainly to
know for sure. The model blend has likely pops but this could
change. Hopefully we'll have a better handle on the situation
tomorrow, especially since it's a busy travel time with Thanksgiving
coming up. Temperatures through the period are expected to be near
seasonal norms.


Aviation...(for the 06z tafs through 06z Thursday night)
issued at 1147 PM EST Wed Nov 20 2019

High pressure across the Great Lakes is providing overall quiet
weather for northern lower Michigan for moment. Another narrow
band of cloud cover is moving through the region bringing MVFR
conditions to parts of northern lower Michigan. But warmer/dryer
low level air is spreading into the region clearing out the low
stuff...although thick mid and high cloud cover is already
spreading across the region.

Meanwhile, storm system is organizing in the Central Plains and
will lift up through the western Great Lakes late tonight through
Thursday. This system will bring steady rainfall to the region on
Thursday and conditions turning IFR. Strong winds aloft will also
develop leading to low level wind shear at the terminal sites late tonight
through Thursday. Steadier rainfall does diminish later in the day
Thursday. Colder air spreads back down through the region Thursday
night and will lead to rain->snow showers at that time.


issued at 224 am EST Thu Nov 21 2019

The pressure gradient is tightening up early this morning, ahead of
low pressure that will cross through the western and northern Great
Lakes today. The system cold front will then sweep across the region
tonight. Gale force winds will be common across many nearshore
waters both ahead of, and behind this storm system. Winds will
weaken some later Friday, but many nearshore waters will still feel
advisory level winds through Friday night, and even Saturday, ahead
of the next cold front. The low pressure system today will bring
widespread rain, which will change over to lake effect rain
and snow showers tonight.


Apx watches/warnings/advisories...
LH...Small Craft Advisory until 9 am EST Friday for lhz345-346.
Small Craft Advisory from 6 am this morning to 1 PM EST Friday
for lhz349.
Gale Warning from 10 PM this evening to 6 am EST Friday for
Lm...Small Craft Advisory until 9 am EST Friday for lmz341.
Gale Warning from 7 PM this evening to 3 am EST Friday for
Ls...Small Craft Advisory until 9 am EST Friday for lsz322.
Gale Warning from 7 PM this evening to 3 am EST Friday for


Near term...smd

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