Area Forecast Discussion
Issued by NWS Grand Rapids, MI

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS63 KGRR 222346
AFDGRR

Area Forecast Discussion
National Weather Service Grand Rapids MI
646 PM EST Sun Jan 22 2017

LATEST UPDATE...
Aviation

.SYNOPSIS...
Issued at 324 PM EST Sun Jan 22 2017

Dense fog is expected to plague the region through tonight, then
visibilities are expected to improve by late Monday morning. Mild
and wet weather will continue through the first half of the week.
Daytime temperatures will be in the 40s Monday and Tuesday, but
we will see good chances of rain Monday afternoon and evening, and
again Tuesday night.

More winter-like conditions should return Wednesday night, and
lasting into next weekend. Temperatures will become more typical
for this time of year, along with chances of snow, especially
Wednesday night through Thursday night.

&&

.SHORT TERM...(This evening through Tuesday night)
Issued at 324 PM EST Sun Jan 22 2017

Dense fog advisory was extended at the morning update until 10 AM
Monday and this still looks good. Most of the area has seen a
diurnal improvement this afternoon, but the regime has not changed
for tonight. So the fog will become dense once again. We will
begin to realize a better pressure gradient late tonight, when
winds begin to pick up as an intense low pressure moves across
NC. So some improvement may occur as early as daybreak (7 AM)
toward I-94, but it should take until 10 AM for Central Lower MI
to improve.

A surface trough will extend from the NC low to Lower MI. This
should continue to supply enough lift to expect periods of drizzle
and/or light rain tonight. Highest chance over the SE CWA, while
portions of the NW may remain mostly dry. As the low moves NE
toward the mid Atlantic Monday, it will act to throw back
moisture into the Great Lakes. More rain will occur across the
CWA, but lightest toward the lakeshore. Even so, expect all areas
will see less than a quarter inch of rain, tonight through Monday
evening. The rain will diminish late Monday night as the low pulls
away and weak surface ridging moves in.

Tuesday should be a mostly dry day, but by the end of the day
another stacked low will be crossing IA. Good moisture advection
ahead of this low, where some light showers may begin by
nightfall Tuesday. However the bulk of the rain will arrive later
in the evening and overnight. A light rain is expected again with
less than a quarter inch expected. I did remove any mention of
snow on Tuesday night as temps are expected to hold steady in the
mid and upper 30s. Progged dew points remain in the low to mid
30s all night.

.LONG TERM...(Wednesday through Sunday)
Issued at 324 PM EST Sun Jan 22 2017

Made some changes to Superblend in the extended. Bumped up POPs
significantly for Thursday night through Sunday for lake effect snow
and lowered temperatures closer to EC guidance.

Sfc low pulling away on Wednesday with rain transitioning to snow
Wednesday night, followed by a period of west flow lake effect snow
showers into the weekend. Best chances for accumulating snow will be
Thursday night into Friday morning as trough moves through and
inversion heights increase to 8 to 10 kft.

Lake effect should decrease on Friday night then pick up again on
Saturday with the passage of another trough which features a Lake
Superior connection and strong sfc convergence across the SW zones.

&&

.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 642 PM EST Sun Jan 22 2017

As the temperature lowers a few degrees tonight...that will allow
for the dense fog to increase once again. Once the thick fog
redevelops...it should persist into Monday morning. Later in the
morning and into the afternoon...the visibilities and ceilings
should improve to perhaps MVFR as rain spreads westward through
the TAF sites.

&&

.MARINE...
Issued at 324 PM EST Sun Jan 22 2017

Dense fog advisory remains for the nearshore areas through 10 AM
Monday. Periods of fog will be likely at times beyond this, with
dew points remaining in the 30s over the chilly waters, so we`ll
have to monitor trends. Otherwise winds and waves will remain
moderate. We may approach small craft advisory conditions Monday
afternoon and evening over the south end of the lake with a
persistent NNW flow of 15-25 knots.


&&

.HYDROLOGY...
Issued at 354 PM EST Sun Jan 22 2017

Ice is no longer an issue on area rivers, but rivers continue to run
above normal. Advisories are out for... the Grand River at Ionia,
Lowell, and near Comstock Park...  Looking Glass River near Eagle...
Thornapple River above Hastings... Sycamore Creek at Holt... and
Maple River at Maple Rapids. A little light rain is possible tonight
into Monday night with light rain/snow possible Tuesday night
through the work week. This should have little effect on river
levels, so no flooding is expected into next week.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...Dense Fog Advisory until 10 AM EST Monday for MIZ037>040-043>046-
     050>052-056>059-064>067-071>074.

LM...Dense Fog Advisory until 10 AM EST Monday for LMZ844>849.

&&

$$

SYNOPSIS...JK
SHORT TERM...JK
LONG TERM...Ostuno
AVIATION...MJS
HYDROLOGY...63
MARINE...JK



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.