Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

fxus63 kgrr 151455 
afdgrr

Area forecast discussion
National Weather Service Grand Rapids Michigan
955 am EST sun Dec 15 2019

Latest update...
update

Synopsis...
issued at 313 am EST sun Dec 15 2019

- snow showers ending this morning

- system passes by to the south Monday into Monday Night

- Lake effect snow showers and colder Tuesday into Wednesday

- dryer through the rest of the week

&&

Update...
issued at 948 am EST sun Dec 15 2019

The pops for snow showers were increased this morning. Radar and
observational trends indicate the snow has increased over the past
hour. High res guidance supports a decreasing trend to the snow
showers for the rest of the day. BUFKIT overviews show the
moisture depth decreasing this afternoon which would support a
decreasing trend to the snow showers. Locally some areas could
see perhaps up to an inch of snow for this morning.

&&

Discussion...(today through next saturday)
issued at 313 am EST sun Dec 15 2019

Precipitation has transitioned over to snow this morning with
light accumulations already being seen on top of an icy glaze from
last night's freezing drizzle. Only light snow accumulations of
one inch or less are expected before snow ends by the late
morning. Highest accumulations will be along and west of US-131
and north of I-96. Slick roads can be expected due light snow in
addition to any residual glazing of ice from freezing drizzle last
night.

For the system Monday into Monday night, model trends continue to
suggest a more southerly track, yielding most of the higher snow
totals well to our south and east. That being said, it is still
within the realm of possibility that areas and south of I-94 may
see light snow accumulation of less than an inch by Tuesday
morning, particularly near the Jackson area.

By Tuesday, the flow turns northwesterly as an upper level trough
digs into the Great Lakes. Favorable conditions will support lake
effect snow showers Tuesday into Wednesday as 850mb temperatures
drop into the negative teens and low level moisture increases.
Light snowfall accumulations will be possible, leading to some
travel impacts for Lakeshore counties Tuesday into Wednesday
morning.

Lake effect snow diminishes Wednesday afternoon, then conditions
turn quiet to end the week. We will see a break in precipitation
into next weekend, with more mild temperatures in the mid 30s.

&&

Aviation...(for the 12z tafs through 12z Monday morning)
issued at 618 am EST sun Dec 15 2019

Snow continues this morning with only minor restrictions to
visibilities at times. Otherwise MVFR ceilings continue this
morning. Snow will gradually taper off by mid-day at which point
ceilings will begin to open up towards VFR. Early Monday morning a
system will pass by to the south bringing a slight chance for snow
mainly for the southern taf sites (azo, btl, jxn), but confidence
in impactful weather remains low so we chose to keep it out of
the taf for now.



&&

Marine...
issued at 313 am EST sun Dec 15 2019

Hazardous small craft conditions continue this morning. High
pressure will move in later today leading to improved conditions
with weaker winds and lower waves. Quiet conditions will continue
until Tuesday as winds turn northwesterly and build waves towards
5 to 8 feet through Wednesday.



&&

GRR watches/warnings/advisories...
Michigan...none.
Lm...none.
&&

$$

National Weather Service Glossary of Abbreviations