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Area forecast discussion 
National Weather Service Grand Rapids Michigan
330 am EST Thursday Feb 11 2016

Latest update...
synopsis/short term/long term/marine

issued at 330 am EST Thursday Feb 11 2016

The snow along the Lakeshore will gradually diminish today...but not
completely come to an end. Another 1 to 3 inches will be possible
today. The lull in the snow will be brief tonight as an Arctic
front moves into the region early Friday and flaring up the snow
again. Winds from the northwest will also increase causing blowing
and drifting snow that will linger into Saturday morning. Travel
impacts can be expected...with the worst conditions expected along
and west of U.S. 131. The snow and wind are expected to diminish
into Saturday afternoon. The front will also bring bitter
cold...with wind chill readings around 10 below zero Friday night
and Saturday.

Another system is expected to impact the area with more snow Sunday
night through Monday night. Temperatures will moderate a bit with
daytime highs mainly 25 to 30 next week.


Short term...(today through saturday)
issued at 330 am EST Thursday Feb 11 2016

Will allow the headlines to continue early this morning...but the
feeling is that we will be able to expire them at 10am. Another
impactful system arrives late tonight into Saturday morning when
more headlines will probably be needed.

Inversion levels continue to come down this morning and the that
tend continues through the day. This will result in the intensity of
the snow bands to slowly weaken. And as we move through the
afternoon the winds will turn to the west...forcing the main band
inland as it weakens. Bottom line...Lakeshore areas will see up to
another 3 inches...mainly this morning. Then the snow weakens and
pushes inland. Only a light dusting is expected outside of the
headline area.

Tonight will see a lull in the snow with inversions dropping as low
as 4k feet. However an Arctic front and it/S upper wave will be
approaching late tonight. So expect the snow to increase again after

The front comes through the County Warning Area on Friday and we will see periods of
lake effect snows. Ahead of the front the flow will be
westerly...but then it turns to the north northwest into Friday
night. Areas west of U.S. 131 should see the heaviest snow...but it
seems like a 2-4 inch type snowfall as the snow flake size becomes
small into Friday with the dgz near the ground...not allowing for
much accums. However expect we will need headlines for this event
as the winds will be gusting to around 30 miles per hour. Given the new snow
and the fresh powdery snow we have already on the ground...
significant blowing and drifting will cause impacts.

The wind and snow should subside into Saturday afternoon. However
wind chills will stay zero to 10 below in Saturday.

Long term...(saturday night through wednesday)
issued at 330 am EST Thursday Feb 11 2016

The pattern shifts through the course of the long term period of
Saturday night through Wednesday. Saturday night a deep upper trough
is in place and by early next week it shifts to a flatter west-
northwest zonal flow. What this means for after a cold
weekend we will moderate quite a bit into next week. Highs in the
teens over the weekend will rebound back to near normal into the
lower 30s next tues/Wed.

There will be some lingering lake effect snow showers Saturday
evening at the flow tries to hang on out of the
northwest. Have some light accums during the evening towards Lake
Michigan. A very cold night with below zero lows inland. Wind chill
values will be dipping towards -10f Saturday night.

The remainder of the long term period we will be dealing with
shortwave/S zipping through the zonal flow across the northern tier
of the country. Sunday night into Monday a weak wave moves through
with chances for light snow...followed by another Monday night into
Tuesday. Yet another possibly on Wednesday. Not confident in the
timing of these shortwave/S...and have joined with surrounding
offices in forecasting low chances for light snow almost every
forecast period early/middle next week.

Bottom line...plenty of chances for light snow in the long
term...but no significant systems to deal with. After some of the
coldest air of the winter over the weekend we moderate back to near
normal next week.


Aviation...(for the 06z tafs through 06z Thursday night)
issued at 1154 PM EST Wednesday Feb 10 2016

VFR conditions will prevail tonight and early Thursday with snow
showers focused along the immediate Lake Michigan shoreline. Mkg could see
some brief drops in visibilities... but even there the heavier snow bands
should remain just west of the terminal overnight.

On Thursday the clouds and snow showers should spread back inland
as the winds become more westerly by afternoon. Most of the taf
sites should become MVFR as this occurs although some IFR visibilities
will also be possible... especially at mkg and azo.


issued at 330 am EST Thursday Feb 11 2016

Gales expected by Friday afternoon...small craft through then


issued at 1233 PM EST Wednesday Feb 10 2016

Downward trends continue on the Maple River with minimal concerns
for additional flooding in the near future.

Precipitation forecasts through the next 7 days account for less
than three-quarters of an inch along the Lakeshore and less than
half an inch inland. This translates to little or no concern with
precipitation type mostly consisting of snow.

Temperatures will stay well below freezing today through the
weekend...possibly reaching freezing by next Tuesday. Ice may
begin to develop once again over the weekend as overnight lows
bottom out in the single digits. These temperatures do not last
very long though...and the return to 30s next week may help
mitigate any ice jamming. It is the main focus going through
Saturday and Sunday. Otherwise...fairly quite river-wise.


GRR watches/warnings/advisories...
Michigan...Winter Storm Warning until 10 am EST this morning for miz056-064-

Winter Weather Advisory until 10 am EST this morning for miz037-

Lm...gale watch from Friday afternoon through Saturday morning for

Small Craft Advisory until 1 PM EST Friday for lmz844>849.



short term...jk
long term...Duke

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