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Area forecast discussion 
National Weather Service Grand Rapids Michigan
636 am EST Sat Feb 6 2016

Latest update...

issued at 325 am EST Sat Feb 6 2016

A trough of low pressure across the northern Great Lakes region
will bring a few light snow showers and flurries to north and
central lower Michigan today. A stronger low pressure system will
bring mixed rain and snow showers Sunday. Colder air will move in
on the back side of this system for next week with snow showers.
Temperatures will average much below normal by Wednesday and


Short term...(today through monday)
issued at 325 am EST Sat Feb 6 2016

Dry weather is anticipated for most of our area today but a trough
of low pressure and middle level wave will bring a few light snow
showers and flurries. The relatively best chance for a few of
those will be across our northern forecast area in closer proximity to
the trough axis up toward ldm and north of krqb and kmop. Any snow
would be very light with accumulations under an inch.

Temperatures will moderate and reach the upper 30s to lower 40s Sunday
due to continued south to SW flow warm air advection. A stronger low pressure
system moving in from the northwest will bring mixed light rain and light
snow showers.

Then as thermal profiles gradually cool Sunday night and Monday
any mixed precipitation will gradually transition to snow showers. Snow
accumulations will be quite light at generally around an inch or

Locally higher amounts of around two inches are possible mainly
across the Lakeshore counties as deep moisture lingers on the back
side of the system as suggested by model time height x-sections. A
dry slot further east may limit snowfall over our eastern forecast
area during the day Monday.

Long term...(monday night through friday)
issued at 325 am EST Sat Feb 6 2016

The cold weather will return Tuesday and remain in place until
Monday (15th) when a signifcant warm up starts. We get two surges
of Arctic air this coming week. The first one come in behind the
clipper system Monday... then an even colder surge follows a much
weaker clipper system Friday. The event that follows the front on
Friday drains most of the really cold air out of western
Canada...which is part of why it warms up after that.

So of course there will be lake effect snows through the week into
the weekend. I put near conditional probability of precipitation for our western counties
into Thursday. For most of this event winds are northwest to north
northwest.... so western Mason...western oceania...western
Ottawa..western Allegan and western Van Buren counties would get the
most snow from this event (mon night into thu). I would expect as
we get into Wednesday and more so Thursday we will see a I-94 band set
up...bringing the snow showers east to Jackson. Since dgz gets close
to the ground by Tuesday afternoon... I would expect mostly small
snowflakes so accumulations will not be really high in any one six
hour period...but over the time from Monday night through Thursday night I
could see close to a foot of snow falling in the locations over
western Van Buren County. The other issue is the moisture is fairly
deep with only a minimal inversion Tuesday into midday Wednesday. That
will help to increase snowfall rates. Hard to say how much impact
the lake being warm for this time of year will have. Inland of US-
131 and north of I-94 I would expect very little snow to fall until
the cold front/ clipper system on Friday. Even then I am thinking an
inch or two.

As for the longwave pattern... those two east Asian jet cores (180+
kts) help the cause of building the western ride and maintaining the
cold weather there into next weekend. However after that yet another
system from russian Arctic heads east and pushes the system over
the Gulf of Alaska through the western ridge... which is also why
it will warm up by Monday the 15th.

So my bottom line is cold and snowy near the Lake Shore this week...
cold but not snowy east of US-131 and north of I-94 until some snow
on Friday.


Aviation...(for the 12z tafs through 12z Sunday morning)
issued at 636 am EST Sat Feb 6 2016

VFR ceilings prevail across the taf sites at 1130z...however there was
some mist (5sm br) reported at azo and btl. This may expand
north and east into GRR...lan and jxn in the 12z to 15z time frame
but it should be gone by 15z. Even so a large area of IFR/MVFR
ceilings over Wisconsin is headed this way. The models suggest the
southern edge of this cloud area will largely stay north of I-94.
Once it moves it... it will hang around till around 06z when a
stronger push of middle level warm air pushes the clouds out of the
area. I do not expect any precipitation at any of the taf sites
within the next 24 hours.


issued at 325 am EST Sat Feb 6 2016

South to SW winds mainly in the 10 to 20 knots range are anticipated
through the weekend with wave heights mainly in the 2 to 4 foot


issued at 1134 am EST Friday Feb 5 2016

The Grand River at Ionia and Maple River near Maple Rapids are the
only rivers currently out of their banks. Both are at or near
their crests and will slowly recede into next week. No other
rivers are expected to exceed bankfull at this time. Most river
channels are free of ice... but colder temperatures next week may
lead to ice redevelopment and thus we will have to watch for river
level fluctuations.


GRR watches/warnings/advisories...


short term...Laurens
long term...wdm

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