Area Forecast Discussion
Issued by NWS Grand Rapids, MI

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FXUS63 KGRR 132052

Area Forecast Discussion
National Weather Service Grand Rapids MI
301 PM EST Mon Feb 13 2017

Synopsis/Short Term/Long Term/Marine

Issued at 301 PM EST Mon Feb 13 2017

Mild temperatures will persist through Tuesday. This will be
followed by colder temperatures Wednesday into Thursday with a burst
of snow to the north Tuesday and then steadier light snow by the
lakeshore Wednesday into Wednesday night. Temperatures will rise
dramatically towards the end of the work week with weekend highs
possibly hitting the lower 60s in spots.


.SHORT TERM...(This evening through Wednesday night)
Issued at 301 PM EST Mon Feb 13 2017

Little change in thinking regarding precipitation trends. Clipper
approaches the western Great Lakes early Tuesday night with an
associated rise in lake inversion heights and convective
instability, particularly over Northern Lower Michigan beneath
the strongest upper PV advection. During the day Wednesday, lake
instability maximum shifts towards far Southwest Lower MI with a
longer lake fetch of northwest flow and sufficient inversion
heights aided by the upper jet axis positioned south of the
region. Increasingly anticyclonic surface flow and less favorable
jet placement should end snow rather quickly early Thursday

.LONG TERM...(Thursday through Monday)
Issued at 301 PM EST Mon Feb 13 2017

We are looking potentially record breaking warmth for this coming
weekend and early next week, with mainly dry conditions expected
through the period.

The only chance of pcpn we have in the long term portion of the
forecast is right at the beginning on Thu. Lake effect expected mid-
week will be ending, and an elevated warm front will be pushing
through as the cold air will be moving out.

We still expect to see a progressive warm up from Fri right on
through next Mon. We will see a fairly amplified ridge slowly push
toward the area through Sat as troughing occurs out west. There are
indications that a short wave could beat the ridge down briefly and
try to push a cold front into the area. A westerly low level flow
may temper temperatures a little on Sat with flow off of the
cooler lake.

We look to see more warming take place then Sun and Mon with
temperatures pushing close to record levels in the lower 60s. The
upper ridge will be reinforced as additional energy dives in across
the Western U.S.. This warming will be assisted by the low level
flow becoming more srly and not off of the lake. The reinforcement of
the ridge should also keep pcpn from moving in across the area.


.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
Issued at 1240 PM EST Mon Feb 13 2017

Most of the 18z fcst period will feature limited impacts with
mainly VFR conditions. Most of the terminals will see only some
cirrus cloud cover around 20-25k feet through 12z Tue. Winds from
the SW around 10 knots or less will prevail through this time
frame also. KMKG will likely see winds become a bit gusty to
around 20-25 knots this evening with a wind coming off of the

Toward 12z Tue, an area of low clouds accompanying a cold front
will begin to gradually sink south through the terminals. We
expect these clouds to be around 2k ft or so. Winds will also
become gusty at that time with gusts around 20-25 kts at the
remaining sites.


Issued at 301 PM EST Mon Feb 13 2017

No changes to previous thinking.


Issued at 302 PM EST Sun Feb 12 2017

River levels continue above normal and minor flooding continues on
the Grand River at Ionia. Little precipitation is expected through
the week and temperatures will be above normal, so river levels
should fall into next weekend.


LM...Small Craft Advisory until 7 AM EST Wednesday for LMZ844>849.



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