Forecast Discussions mentioning any of
"ACARS" "MDCRS" "AIRCRAFT" "TAMDAR" "AMDAR" "WVSS" received at GSD on 02/12/19
Area Forecast Discussion
National Weather Service Grand Rapids MI
1021 PM EST Mon Feb 11 2019
LATEST UPDATE...
Update
.SYNOPSIS...
Issued at 310 PM EST Mon Feb 11 2019
- Snow and mixed precipitation moving into the southern zones late
this evening then spreads north after midnight.
- Mostly snow north of I-96 and up to a quarter inch of ice along
I-94.
- We expect a lull late Tuesday morning and afternoon then snow
returns Tuesday evening with strong winds and blowing snow for
Tuesday night and Wednesday morning.
- Another storm could bring snow or a mix Thursday night into
Friday morning.
&&
.UPDATE...
Issued at 1016 PM EST Mon Feb 11 2019
No major changes to the forecast with the update. I did add some
more freezing rain to the southern parts of the CWA. Aircraft data
and surface obs indicate the warm layer is already into parts of
far southwest MI...warranting more freezing rain for the region.
Will need to monitor the dry slot as it may limit the overall
accumulations. The convective cluster down in OK is associated
with a PV anomaly...which arrives here in the CWA around 21z Tue.
&&
.DISCUSSION...(This evening through next Monday)
Issued at 310 PM EST Mon Feb 11 2019
We replaced the advisory with a warning for the northern third of
the the forecast area where heavier snow is expected and the
potential for high impacts in falling and blowing snow occurs late
tonight into Tuesday morning and again Tuesday night into
Wednesday morning. We continue the advisory elsewhere with an
earlier start time across the south.
This is a two-stage event with the first batch tonight bringing
the threat of icing across the southern forecast area and a quick
3 to 5 inches of snow further north. Most model soundings show
mostly sleet during the heavy burst of warm advection precip late
tonight across the south, but there could be a couple hours of
freezing rain that would cause travel impacts and possibly enough
icing to cause some power outages. The soundings do not appear to
be as favorable for freezing rain as the recent event, but up to a
quarter inch of ice is possible and, combined with strong east
winds gusting over 30 mph, power outages are a concern.
The dry slot moves through on Tuesday as the 850 mb low tracks
across the central forecast area. Some freezing drizzle is
possible across the north and central zones with drizzle across
the south as sfc temperatures rise above freezing.
Wrap-around snow moves in Tuesday evening with cold advection
helping mix down strong wind gusts over 35 mph. Temperatures drop
and blowing snow is expected to become widespread by Wednesday
morning, similar to the conditions we saw last Friday morning.
The lake effect snow will taper off by Wednesday night as sfc
ridging builds in. The calm weather will be short-lived as a
northern stream shortwave trough amplifies as it is moving in on
Thursday and there is the potential for a quick hitting event
Thursday night with snow or mixed precip. Still time to watch this
as ensemble spread remains considerable.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 638 PM EST Mon Feb 11 2019
Impacts will continue to increase at the TAF sites tonight as a
band of snow strengthens as it moves in from the southwest. In
addition the wind will be on the increase with gusts over 25 knots
likely to develop. As a warm layer tries to move in from the south
late tonight into Tuesday it should switch the precipitation over
to a mix which should include freezing rain/sleet. A lull in the
intensity looks likely for the middle part of the day when the
wind may drop off as well. Then by mid afternoon colder air starts
wrapping in from the southwest along with another burst of mostly
snow with expected impacts.
&&
.HYDROLOGY...
Issued at 310 PM EST Mon Feb 10 2019
Nearly all rivers in our area have now crested after responding to
the volatile weather of the last 10 days. The one exception is on
the Grand River, where a very broad crest continues to work its way
downriver, and has passed through Grand Rapids in the last 24 hours.
There continues to be a major ice jam causing ongoing flooding in
the City of Portland. This jam has not changed significantly in the
last 24 hours. Reports from Portland indicate water levels have
dropped only slightly over the weekend. There is another ice jam
that we are monitoring near Eastmanville, near the 68th Avenue
bridge. This ice jam is currently fairly small, and is not currently
resulting in additional flooding. There are no ice jams in the Grand
Rapids area, but we are still monitoring that potential as the water
will remain high for at least several more days.
As we head into another week of rapidly-changing and high-impact
weather, any additional rainfall or snowmelt will send more water
into the rivers, and delay the already-slow drop we need on our
larger rivers. So far it looks like much of the area will see mostly
snow this week, which will not have an immediate impact on the
rivers, but will set the stage for future snowmelt.
&&
.CLIMATE...
Issued at 310 PM EST Mon Feb 11 2019
Here are the record snow totals for February 12th...
Muskegon...3.9 inches in 1969
Grand Rapids...4.2 inches in 1964
Lansing...5.0 inches in 1894 and 1897
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 1 PM EST Wednesday for MIZ058-059-
064>067-071>074.
Winter Storm Warning until 1 PM EST Wednesday for MIZ037>040-
043>046.
Winter Weather Advisory until 1 PM EST Wednesday for MIZ050>052-
056-057.
&&
$$
UPDATE...MJS
SYNOPSIS...Ostuno
DISCUSSION...Ostuno
AVIATION...MJS
HYDROLOGY...Dixon
CLIMATE...Ostuno