Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

fxus63 kgrr 201915 
afdgrr

Area forecast discussion
National Weather Service Grand Rapids Michigan
315 PM EDT Thu Jun 20 2019

Latest update...
synopsis/discussion/marine/Hydro

Synopsis...
issued at 315 PM EDT Thu Jun 20 2019

- drying out Friday through most of Saturday

- unsettled and stormy period at times Sunday through Tuesday

- quieting down briefly next Wednesday

&&

Discussion...(this evening through next thursday)
issued at 315 PM EDT Thu Jun 20 2019

Our attention is starting to transition from the rain event last
night and this morning, to the next potential wet period that looks
to be Sunday through Tuesday.

The last of the rain from this last system is just about to exit
east of the area as of 19z/3 PM EDT this afternoon. We should see a
mostly dry couple of days as a fairly sharp upper ridge slowly
builds over the area, and a Canadian sfc ridge funnels drier air
over the area. The ridge will only slowly build east, helping to
keep the drier air in a little bit longer. It is possible that a mesoscale convective system
may come as close to US as Chicago Fri night/Sat morning. It looks
like the instability gradient and flow will stay just far enough SW
to allow for a dry forecast into Saturday.

The better chance for storms will come in beginning on Sunday. This
is the case as the long wave trough over the plains will lift a sfc
low to the NE, and give the warm front/instability gradient enough
of a push to make it over the area. It appears that there will be
multiple waves that move through in the SW flow aloft. Tough to give
any details about a complicated situation with short wave activity,
timing, degree of instability etc... however, we will have the
potential to build decent instability at times, the flow aloft will
be conducive for organization of storms, and we will have plenty of
deep moisture to work with. This could end up being a fairly busy
period at times with severe weather and some flooding possible.

We should see the system move out by Wednesday, which would allow
for the area to dry out again with high pressure building overhead.
Right now, this dry period looks limited in duration as short waves
look to move toward the area again on Thursday.

&&

Aviation...(for the 18z tafs through 18z Friday afternoon)
issued at 145 PM EDT Thu Jun 20 2019

Rain and IFR conditions that have plagued the area since last
night, is now improving and gradually moving out from west to
east. This trend will slowly continue through 00z this evening.
This will occur as clouds lift from IFR to MVFR, the clouds will
eventually scatter out. Clouds will be limited after 03z or so,
through the end of the period. Winds will slowly shift from NE, to
the NW, and even west for Friday.

&&

Marine...
issued at 315 PM EDT Thu Jun 20 2019

Weather impacts to mariners will be rather limited through Saturday,
with winds expected to be under 20 knots. Impacts look to ramp up a
bit for Sunday, and will last through Tuesday as a fairly decent
sized system slowly moves through the region. We are looking at
small craft advisories being likely during that time frame, along
with multiple chances of stronger storms.

&&

Hydrology...
issued at 315 PM EDT Thu Jun 20 2019

The rain event from last night through this morning is winding down
across the area. Rainfall amounts ranged from around an inch up
north, to as much as locally around 5 inches around the Kalamazoo
area. The flood advisory for most of the southern two rows of
counties (except Jackson county) was extended into Friday with roads
closed, and standing water remaining in place. Two river points are
under a Flood Warning, Eagle on the Looking Glass river, and
Vicksburg on the Portage River are forecast to come up to flood
stage. The rest of the rivers are still expected to see significant
rises, but staying within their banks.

We will have a chance for things to stabilize a bit, with what looks
to be almost 48 hours of dry weather and sunshine with longer days.
However, we will need to watch the period from Sunday through
Tuesday closely. There looks to be a potential of multiple rounds of
storms with the next system expected to affect the region for a few
days. Locally heavy rainfall will be possible with each round, which
will not be good on saturated soils from this recent event.

&&

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

$$

National Weather Service Glossary of Abbreviations