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fxus63 kgrr 241115 
afdgrr

Area forecast discussion
National Weather Service Grand Rapids Michigan
715 am EDT Mon Jun 24 2019

Latest update...
update/aviation

Synopsis...
issued at 330 am EDT Mon Jun 24 2019

-humid with scattered showers and thunderstorms today

-a few strong storms possible this afternoon/evening

-dry and less humid on Tuesday, followed by another chance of
storms on Tuesday night

-very warm and Summer-like mid to late week

&&

Update...
issued at 715 am EDT Mon Jun 24 2019

Recently cancelled the Flood Watch for the southern two rows of
counties. Heavy rain did not materialize overnight and while a
few thunderstorms this afternoon and evening may still produce
brief heavy downpours, total rainfall amounts are not expected to
be excessive. Plus the area of higher precipitable water air near 2 inches is
now moving away to the northeast with the shortwave, and values
drop to 1.5 inches or lower in it's wake.

&&

Discussion...(today through next sunday)
issued at 330 am EDT Mon Jun 24 2019

Shortwave currently lifting northeast through lwr Michigan producing
scattered showers early this morning, especially north and east
of GRR. Even a hint of an mesoscale convective vortex in radar data east of GRR. This
wave lifts out around daybreak, although a few isolated showers
may linger in it's wake this morning as sfc warm front continues
lifting north through the area.

Coverage of showers and tstms should increase around mid
afternoon with the approach of the sfc cold front and negative
tilt upr shortwave. However it's questionable if we'll see much
sfc based instability with extensive cloud cover, and the
Lakeshore areas north of Holland should be quite stable with south-southwest
winds off the cold water.

Ensemble mean sbcapes are progged to be roughly 750-1000 j/kg
late this afternoon which may be just enough the generate a few
stronger storms since deep layer shear ramps up to near 40 kts as
upr trough approaches later in the day. Limiting factor however
is poor mid level lapse rates, which look better over WI under
the upr trough.

It's very possible we'll be spared from svr wx and locally heavy
rain today, with events occuring to our southeast over Ohio (sfc
cold front) and to the west over WI (upr trough). Will keep the
Flood Watch in effect for now but may be able to cancel early.

We dry out tonight and Tuesday however a period of convection
looks possible Tuesday night as the elevated mixed layer leans in
from the west and a weak boundary drops in. The mid to late week
period currently looks quite warm/Summer-like with our next risk
of storms coming in on Friday. Other scattered, mainly diurnal,
storms may occur next weekend inland from lk Michigan.

&&

Aviation...(for the 12z tafs through 12z Tuesday morning)
issued at 715 am EDT Mon Jun 24 2019

IFR has become widespread early this morning, but should begin to
gradually lift to MVFR levels by mid morning. Exception may be at
mkg where marine stratus/fog could linger much of the day or
oscillate in and out.

Cigs lifting to VFR levels this afternoon, but scattered tstms
expected from mid afternoon through early evening ahead of an
approaching cold front. Gusty winds may accompany these storms.
Convection diminishing this evening with fropa, although MVFR cigs
will probably return after 06z... dropping in from the north
behind the cold front.

South sfc winds around 10 kts this morning becoming southwest at
10 to 20 kts this afternoon into tonight.

&&

Marine...
issued at 330 am EDT Mon Jun 24 2019

We will be dealing with some dense marine fog today as high dew
pts interact with the cold lk Michigan waters and winds turn onshore.
Wind crank up tonight into Tuesday out of the southwest, and drier
air arrives, which should mix out the fog. However those higher
winds will require a Small Craft Advisory and potential beach
hazard statement.



&&

Hydrology...
issued at 325 PM EDT Sat Jun 22 2019

Very High River levels for this time of year continue following
thursday's heavy rain in the Kalamazoo and grand basins. Urban and
small stream flooding is also possible with any heavy downpours from
storms today, especially in the Kalamazoo area where flooding
already occurred Thursday and the ground is still nearly saturated.
Fortunately any storms that develop today should not stay in one
spot for long, but we will maintain the Flood Watch given the area's
vulnerability.

&&

GRR watches/warnings/advisories...
Michigan...none.
Lm...dense fog advisory until 8 PM EDT this evening for lmz846>849.

Small Craft Advisory from 8 PM this evening to 8 PM EDT Tuesday
for lmz844>849.

&&

$$

Update...Meade

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