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Area forecast discussion 
National Weather Service Gaylord Michigan
310 PM EDT Fri Oct 28 2016

Short term...(this evening and overnight)
issued at 258 PM EDT Fri Oct 28 2016

1003 mb low pressure centered across northwest Minnesota will
track by to the north of Michigan tonight and drag a cold front
across the region early Saturday. South southwest winds out ahead
of this system will remain gusty at times. Chances for showers are
expected to be mainly confined to northern zones as moisture
remains rather shallow. More of a drizzle looking sounding across
the remainder of the area with patchy fog also likely developing.
Mild with temperatures steady to slowly rising into the lower and
middle 50s overnight.

Long term...(saturday through friday)
issued at 258 PM EDT Fri Oct 28 2016

Saturday...low clouds and patchy fog will slowly lift Saturday
morning behind the departing cold front. This will leave mostly
cloudy conditions through the day. Temperatures will be steady to
slowly falling through the 50s.

Saturday night through Monday...

High impact weather potential: none.

Progressive upper flow to continue. At the surface, slow-moving
cold front will slip south of Michigan by Sunday morning. Before it does,
a shortwave moving toward Southern Lake Michigan will contribute to an
increase in precip north of this front Sat night. That will result
in some rain chances, especially in northern lower Michigan. Large high
pressure will result in dry and cool wx Sunday and Sun night.
Strong warm advection kicks in again behind the high for Monday,
resulting in breezy/windy and mild conditions by trick-or-treating

Sat night...there are a couple of precip-generating mechanisms in
play. One is the incoming shortwave encountering an unstable
airmass. That is in play in extreme Southern Lower Michigan and adjoining
parts of in/OH, where MUCAPES will approach 1k j/kg. Don't see a
thunder threat this far north. Instead, frontogenetic forcing will
be the primary player, as the shortwave and associated weak surface
low to our SW tightens the 850mb temp gradient (especially overnight
in central/southern lower mi). NAM precip progs have a banded, fgen-y
look to them (especially to our west). Note that the NAM has
exhibited a slowing trend to precip onset, one that is not supported
by the rest of the model suite.

Pops will be highest in the south, with likelys near Gladwin/
Standish. Precip will dwindle with northward extent, and no precip
will be mentioned north of M-68. Even on the northern fringe and over
the higher terrain, the surface-based melting layer is 2500ft or so.
So, barring major changes, there is little/no risk for snow.

Min temps upper 30s to lower 40s.

Sunday/Sun night...high pressure starts Sunday near Minnesota, and passes
between James and georgian bays Sun night. There is perhaps a risk
of some showers lingering near Saginaw Bay at the start of the day
Sunday. Otherwise, cool but much drier low-level air will enter the
region on northerly breezes during the day. Cloud cover will be
decreasing during day. Return flow will just start to get going late
Sun night, but warm advection-related clouds will spill back in,
supporting partly cloudy skies even as lower clouds diminish

Max temps in the mid 40s to around 50f. Min temps in the 30s.

Monday...return flow will increase thru the day, behind the
departing high, and ahead of low pressure moving from the Dakotas
into Minnesota. Plenty of mid and high clouds will feed into the region
during the day. Any focus for precip looks to be along and
especially north of a warm front, which extends from the low across
the Keweenaw and on into eastern Upper Michigan. Main risk for any precip
looks to be well to our NW, but the possibility exists for a little
rain to reach eastern Upper Michigan (mainly in the afternoon). Some
slight chance to chance pops in order up there, especially north of

Increasing cloud cover otherwise, with Max temps upper 40s to mid
50s. Breezy south winds in the afternoon and evening, perhaps
outright windy along the coastlines (gusts to 30-ish mph).

Extended (monday night through friday)

500mb pattern is generally zonal through the extended...with a
periodic ripple developing, resulting in a couple transient troughs
that move quickly through the flow. At the surface, this will
translate into a fronts that will bring shots of precipitation to
the area. The rapid movement of these features will make timing a
challenge. Right now, it looks like the first trough will be pushing
through at the start of our period...which, of course, is Monday
night and "trick or treat" time. Blended solutions put likely pops
in the eastern upper...with chance pops in the northern lower.
Again, the timing will be tough, just speed up (or slow down) the
scenario by a couple hours...and the kiddies are in the clear. The
only high confidence call for this time is that it's going to be
quite breezy and mild. The next feature is then progged to move
through Wednesday and clear the area by Thursday morning. Outside
of these times...dry weather is expected to prevail and temperatures
will be well above normal by some 10 degrees or so.


Aviation...(for the 18z tafs through 18z Saturday afternoon)
issued at 141 PM EDT Fri Oct 28 2016

Tough set of tafs with low pressure moving by to our north
tonight. This system will drag a cold front across the area late
tonight into early Saturday. Meanwhile...another area of low
pressure will move by to our south Saturday afternoon. The bottom
line to all this is that MVFR cigs will lift for a few hours this
afternoon then drop down to IFR or even LIFR later tonight along
with a few showers and drizzle. Low level wind shear is also
expected to develop later tonight. Cigs are then expected to
slowly lift toward the end of the taf period or the beginning of
the next set of tafs.


issued at 258 PM EDT Fri Oct 28 2016

Strong southwest flow strengthens through this evening. A few
gale force wind gusts remain possible across a majority of Lake
Michigan through tonight. Small craft advisories for the rest of
the nearshore marine areas through Saturday. Winds/waves will
diminish Saturday night into Sunday as high pressure builds in
from the west.


Apx watches/warnings/advisories...
LH...Small Craft Advisory until 6 PM EDT Saturday for lhz345>348.

Small Craft Advisory until noon EDT Saturday for lhz349.

Lm...Small Craft Advisory until 6 am EDT Saturday for lmz323.

Gale Warning until 2 am EDT Saturday for lmz341-342-344>346.

Ls...Small Craft Advisory until 6 PM EDT Saturday for lsz321-322.



Short term...Sullivan
long term...jz/kab

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