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Area forecast discussion 
National Weather Service Gaylord Michigan
617 am EDT Friday Oct 31 2014

issued at 352 am EDT Friday Oct 31 2014

A strong cold front will usher in an early taste of winter weather
today...with areas of snow showers...gusty winds...and temperatures
that will be several degrees below normal. Other than a few
lingering flurries tonight and early Saturday near the Great
Lakes...dry and chilly weather is expected this weekend.
Temperatures will moderate heading into next week...with additional
rain chances returning Monday night and Tuesday.


Short term...(today through tonight)
issued at 352 am EDT Friday Oct 31 2014

Overview: potent shortwave now diving south-southeast through Wisconsin this
morning with associated plunge of substantially colder air
spilling into the northern Great Lakes. Attending surface low pressure
center continues to deepen over Central Lake Huron this hour while
associated cold front is not dropping down through northern lower
Michigan. Not a particularly deep low pressure system (1012 mb or
so). But strong surface high pressure system already edging into the
upper Midwest behind this system has created a Stout p-gradient
behind the low...with winds turning quickly north and ramping up
into the sustained 15 to 30 knot range and gusts pushing 40 knots
just upstream.

Meanwhile...widespread precipitation spans much of the western Great
Lakes with this system. With the cold air spilling into the
region...precipitation changeover to snow now runs from roughly eastern
Upper Michigan back into south-central Wisconsin...pretty much
following the forecast 925 mb 0c line.

Today...potent upper wave passes rapidly down through the lower
lakes into the Midwest this morning with upstream high
pressure...strong subsidenc/drying taking shape across northern
Michigan quickly this afternoon into this evening. But have to
get through several more hours of strong qg-upward forcing/
categorical probability of precipitation before tapering off precipitation chances north-S through
the afternoon. Lake enhanced precipitation will not be a huge player in
this event with winds turning sharply for parts of
the immediate Lake Michigan and Lake Huron shoreline areas.

P-type...anticipate a rather quick transition over to snow this
morning as very cold air slams into the region...although precipitation
will likely remain mixy near the coasts. Snow will be most
persistent across the high terrain of northern lower Michigan this
morning where around an inch of slushy accumulation is
possible...although warm ground temperatures should keep accumulations in

Headlines...inherited wind advisories for all northern Lower Lake
Michigan counties which looks fine for now with core of 50 knot 800 mb
winds passsing down through Lake Michigan this morning. Winds
could get close to advisory levels for a time along the immediate
Lake Huron coast but do not plan on adding any wind headlines at
this point. Winter weather headlines...anticipate only around an
inch of accumulation with rather wet snow that should/T pose to
much of a blsn threat...despite the gusty winds. Thus...not
planning any winter weather headlines either although a few
special weather statements may ultimately be in order.

Tonight...strong subsidence and rapid drying will largely clear
things out across inland areas. Lake clouds/snow showers or
flurries a good bet along the immediate Lake Michigan and Huron
shorelines in northerly flow.

Long term...(saturday through thursday)
issued at 352 am EDT Friday Oct 31 2014

.Up/down pattern set to continue...

High impact weather potential: nothing significant

Pattern synopsis/anticipated evolution: pattern looks to remain
progressive/agressive...with lack of downstream blocking and an
agitated Pacific regime supporting such. Specifics are
eluding...however...with such a fast evolving pattern and tight
thermal gradient creating plenty of uncertainty...especially as we
head into the middle and end portions of the forecast. Gut feeling is
the overall features will look quite a bit different than what is
currently advertised in Middle Range guidance forecasts. We shall see.

Forecast details: deep layer subsidence the name of the game this
weekend as current troughing gets The Boot east as middle level ridging
builds overhead. Core of coldest temperatures /h8 near -10c/
overhead early Saturday morning...producing excellent near surface
over-water instability environment. Instability will be very
shallow...with sharp 800 mb inversion and noted dry tongue extending
even closer to the surface. Hard not to envision at least some
shallow strato-cumulus and possible flurries in favored north to
northeast flow areas to start the day...driven simply by magnitude
of Delta T/S. Drying wins out there-on-after...with skies trending
mostly clear all areas by later in the day. Mostly clear/dry weather
prevails through the remainder of the weekend.

Dry weather to start next work week gives way to increasing rain
chances Monday night into Tuesday as warm...moist advection ramps up
on backside of departing surface high and out ahead of elongated
troughing. Narrow...but well organized...Gulf moisture plume along
passing cold front should only help the shower cause later Monday
night/early Tuesday...supporting inherited likely/high chance shower

As mentioned earlier...confidence really takes a nose-dive heading
into middle and late week as guidance continues to struggle with
interaction /or lack thereof/ of strong upper jet cores rotating
over and off the Pacific. Pattern appears ripe for more amplification
than currently advertised...with even hints of such in various
ensemble output. Have little choice but to follow a guidance blend
approach for now...letting future trends takes US were they may in
the coming days.

Temperatures...very chilly start...with highs mostly in the 30s way to moderation...with highs trending to much
more seasonal levels into the start of next work week.


Aviation...(for the 12z tafs through 12z Saturday morning)
issued at 616 am EDT Friday Oct 31 2014

Solid MVFR conditions anticipated at the terminal sites today as
colder air slams into northern Michigan...turning ongoing precipitation to
snow or a rain/snow mix. Precipitation will wind down quickly this
afternoon and tonight with conditions transitioning to VFR as
strong high pressure and dry air build across the region.

Winds...turning very gusty from the north this morning with gusts
of 30 to 35 knots common. Gusts will subside a bit tonight but
persist into the 20 to 25 knot range through Saturday morning.


issued at 352 am EDT Friday Oct 31 2014

Very gusty northerly winds develop quickly this morning with gale
force gusts anticipated across much of the Great Lakes through the
day. Winds will diminish this evening but likely remain on the
gustier side through the night but should fall back below gale
force. Winds further diminish through the day Saturday and
Saturday night.


Apx watches/warnings/advisories...
Michigan...Wind Advisory until 8 PM EDT this evening for miz016-019>021-025-

LH...Small Craft Advisory until 5 am EDT Saturday for lhz345-346.

Gale Warning until 5 am EDT Saturday for lhz347>349.

Lm...Small Craft Advisory until 5 am EDT Saturday for lmz341.

Gale Warning until 11 PM EDT this evening for lmz323-342-344>346.

Ls...Small Craft Advisory until 5 am EDT Saturday for lsz321-322.



short term...tba
long term...msb

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