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fxus63 kiwx 201049 

Area forecast discussion
National Weather Service northern Indiana
649 am EDT Thu Jun 20 2019

issued at 338 am EDT Thu Jun 20 2019

Showers and a few storms will continue this morning but the amount
of coverage should decrease through the day. Torrential rain and
flooding remain possible with the heavier showers. Morning fog is
possible Friday before a dry and partly to mostly sunny day.
Unfortunately rain and storm chances return again Friday night and
will continue through the weekend and into early next week as the
wet pattern continues. Heavy rain and a few strong storms are
possible through the weekend.


Short term...(today and tonight)
issued at 338 am EDT Thu Jun 20 2019

Slow moving short wave to take its time exiting the area today.
Associated surface low will move along quasi-stationary boundary
in our south and finally exit the east later this afternoon. Wrap
around deformation rain seen nicely on radar and this will
transition east this morning. Fortunately rain overnight has not
been has heavy as expected with rainfall rates around a half to
one inch per hour. Despite slow movement, stronger returns have
been progressive and this has helped lower flood threat as well.

Expect showers and a few thunderstorms today to gradually diminish
from west to east. However, rather sharp cyclonic flow on backside
of system with peak heating and plenty of residual moisture will
likely lead to additional shra/tsra development late morning and
afternoon, especially across the south to the east closer to
boundary and surface wave. For now have left Flash Flood Watch
intact with uncertainty in cam output as to where stronger
convection will fire. This will likely be trimmed off in the west

Some rain chances continue this evening with cams showing a few
stubborn showers within cyclonic flow lingering through 03z. Kept
a slight chance in from 00-03z but expect loss of heating and
subsidence with approaching high pressure to finally end the rain
threat. Fog then a concern overnight as ridge axis builds over the
area and winds become light or calm with skies likely clearing.
Added patchy fog to grids with this pattern similar to what we saw
a few mornings ago.


Long term...(friday through wednesday)
issued at 338 am EDT Thu Jun 20 2019

Nothing new here as active wet pattern continues. Uncertainty
remains high given fast flow and difficult nature to timing short
waves in this ridge riding pattern. Surface ridge slides east on
Friday and another warm front will approach from the west. Models
all show a decent short wave accompanying this feature but
differences develop with how far east it will make it and timing
of possible mesoscale convective system diving southeast along instability gradient near
front. Similar differences continue through the weekend with ridge
likely just to our west and more energy spilling over top and
sending mesoscale convective system/S southeast. Each one of these potential systems will
impact timing and location of each successive system so trying to
add any pop detail is a futile process. Really no choice but to
run with National blend though did limit some of the higher pops
to likely category versus categorical.

Pwats continue to run from 1.5 to 2.0 inches during the period so
heavy rainfall and flood threat will continue to be prevalent
through next week.

Temperature forecast also quite difficult as warmer temps aloft
build in with ridge but abundant moisture will likely lead to
clouds and pcpn at times. Consensus blends may be a bit on cool
side compared to warmth that could be realized if subsidence
develops and skies clear one afternoon.


Aviation...(for the 12z tafs through 12z Friday morning)
issued at 643 am EDT Thu Jun 20 2019

A meso convective system was moving across northern Indiana early
this morning. There were a few lightning strikes, but mostly
light to moderate rain with a few areas of heavy rain. Low IFR
conditions were across the area, although breaks in the lower
clouds were allowing some MVFR conditions. Gradual improvement is
later expected during the afternoon as rain ends and as winds
become northwest. Skies should become partly cloudy overnight with
chances for fog before daybreak.


Iwx watches/warnings/advisories...
in...Flash Flood Watch until 5 PM EDT /4 PM CDT/ this afternoon for

Beach hazards statement through this afternoon for inz003.

Lakeshore flood advisory until 6 PM CDT this evening for inz003.

Michigan...Flash Flood Watch until 5 PM EDT this afternoon for miz077>081.

Ohio...Flash Flood Watch until 5 PM EDT this afternoon for ohz001-002-



short term...Lashley
long term...Lashley

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