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fxus63 kgrr 192347 

Area forecast discussion
National Weather Service Grand Rapids Michigan
747 PM EDT Wed Jun 19 2019

Latest update...

issued at 324 PM EDT Wed Jun 19 2019

- soaking rain expected for southern lower tonight and Thursday

- rain chances return for the weekend after a dry Friday

- fairly unsettled weather Saturday through next Tuesday


Discussion...(this evening through next wednesday)
issued at 324 PM EDT Wed Jun 19 2019

Our initial concern with the forecast is the rain event from tonight
through Thursday, along with convective potential. The focus will
then shift to a potentially wet and unsettled pattern taking shape
from the weekend and through early next week.

We have a few ongoing cells of storms across the southeast corner of the
area this afternoon as of 3 PM. These cells are out ahead of the
cold front that has pressed through the area, except toward Jackson
which still has southerly winds. Outflow boundaries have likely
undercut some of the storms, and reinforced the front a bit. We
expect that the storms should eventually choke out in the next few
hours, and leave a brief break for the area.

We will then see more widespread rain move back up into the area
later this evening, and overnight tonight. This occurs as the well
defined upper low/wave to our SW in the Illinois/IA/MO border will
translate east-southeast slowly tonight and Thursday. There is a lot of
convection down there, but it will be slow to make its way north. By
then, we will lose diurnal instability, and the better instability
will stay along and south of I-94. We will just see a lot of the
rain with this in the deformation zone on the northern flank of this
low/trough. We expect some heavier downpours embedded in the rains,
with the mid level fgen in the deformation. The rains will continue
through a good chunk of the day on Thursday, before the entire low
moves out.

We should see a mainly dry day on Friday, before rain chances return
on Saturday. We will have a ridge at the sfc and aloft build east
through the area. This will be short-lived however as we see a warm
front develop to our SW, and push NE toward the area. It looks like
it will not push through the area until later Sunday or so. Clusters
of storms look to ride along the front, which will likely hold it
back a bit. At the moment, it looks like the axis of heavier rains
would be to our SW. If this front makes it up far enough toward the
area, we could get involved in the heavier rains.

Eventually, we should see the main low eject from the plains, and
lift the front northeast through the area. The low will be close
enough, that periods of storms will become more likely Monday. This
could be interesting also, as the jet looks fairly robust, and could
bring some severe weather chances to the area. A lot of uncertainty
yet, but we are monitoring. Things look to eventually settle down by
mid week next week as this system moves east of the area.


Aviation...(for the 00z tafs through 00z Thursday evening)
issued at 746 PM EDT Wed Jun 19 2019

There is little question rain, heavy at times will move into the
I-94 taf sites by midnight and continue until around noon. I would
expect solid IFR if not some LIFR in rain, fog and low clouds in
that area (azo, btl and jxn). For the I-96 taf sites, lan will be
on the edge of the heavier rain, they too could be solid IFR in
rain, fog and low clouds from around 06z till around 20z when they
should become at least MVFR. GRR and mkg will be more on the
northwest edge of this event, still I would expect at least MVFR
cigs/vsby in rain, light fog and ceilings. Some clearing is
possible after 21z, more so for the GRR, mkg, azo and btl taf
sites. Winds will mostly be light from the northeast tonight into


issued at 324 PM EDT Wed Jun 19 2019

We do not anticipate any major marine issues over the next few days.
Winds well above the surface will increase some with the approach of
the wave tonight. These winds should remain off of the surface, and
not produce many impacts. Winds should diminish then on Thursday as
the system moves out tomorrow. The next chance of an increase in
winds looks to happen on Saturday ahead of the next system.


issued at 324 PM EDT Wed Jun 19 2019

We are looking for a good chunk of the area south of a Muskegon to
Mt. Pleasant line that will likely see an inch or more of rainfall
tonight and Thursday. The good thing with this is that it will be
spread out over about 18 hours or so. The bad thing is that this
will be a widespread 1-2 inches, so the grand and Kalamazoo rivers
will likely see a decent rise in levels. Right now, we do not
anticipate any appreciable flooding, but will watch for that

We will see a break then from late Thursday through Friday to give
the area a brief reprieve. Would could be looking at on and off rain
from Saturday into the middle of next week. There is a potential
that some of this could be heavy at times. This may be a bit more
problematic if we do get those periods of rain. There is still a bit
of uncertainty with that being a few days out.


GRR watches/warnings/advisories...



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