713 
FXUS63 KIWX 161726
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
126 PM EDT Fri Aug 16 2024

.KEY MESSAGES...

- Showers and some storms possible this morning mainly through 
  10 AM EDT.

- Additional showers and a few thunderstorms possible this
  evening, especially for areas east of I-69.

- Periods of showers and thunderstorms Saturday through Sunday,
  best chances will be in the afternoon/early evening.

- Dry and pleasant next week.

&&

.DISCUSSION...
Issued at 324 AM EDT Fri Aug 16 2024

A convective complex that developed over eastern IA last night
and moved eastward through central/northern IL prompting some
severe thunderstorm warnings mainly due to winds. This cluster has
continued to move eastward early this morning and has weakened
on the northern half of the convective cluster, which will be
the portion that mainly affects the western parts of the CWA
from now through about 10 AM EDT as it moves east through the
remainder of the CWA. Will be monitoring this system as it moves
through as strong winds are still possible with this cluster as
it transits through the area. Current 07z mesoanalysis shows
MUCAPE values around 1000 j/kg moving into northern IN with bulk
shear values around 30 kts along with an influx of moisture
in it's wake which will bring increased dew points with values
into the 70s by later today. The system also is moving fairly 
quickly at about 40 kts. A few strong storms this morning are 
not out of the question however, with a bit more vertical 
resistance should work to keep storms on the weaker side. 

With this complicated pattern the guidance has struggled the
last couple of days and therefore have lower confidence on the
exact evolution through today. Thinking is with this morning's
convection moving through we do get some re-development later
this afternoon ahead of a eastward moving cool frontal boundary.
Due to this mornings convection, the afternoon environment will
be worked over and the convective debris clouds will stick 
around through early afternoon with the moisture influx. The 
question then becomes how much will these aforementioned factors
keep the surface instability at bay and reduce the amount of 
re- development this afternoon, as well as potentially keeping 
any thunderstorms that do develop much tamer than would have 
been otherwise. SPC still has our forecast area mostly under a 
marginal risk, which an isolated severe thunderstorm especially 
east of I-69 is certainly not out of the question later today. 
The main threat with any of the storms remains to be gusty winds
but some small hail will also be possible. Highs today will top
out in the low to mid 80s.

The low pressure center associated with the active weather will
push southeastward and pass just to the north and northeast of
the area. This will keep provide a westerly flow aloft that will
bring a couple of weak impulses through the area bringing
periods of showers and thunderstorms for the entire area on
Saturday into Sunday morning and again on Sunday afternoon when
a northerly flow on the backside of the low pushes in bringing
dry weather along with seasonable temperatures Monday through 
late next week. Will be very comfortable weather with dew points
and low temperatures by Tuesday falling into the 50s.

&&

.AVIATION /18Z TAFS THROUGH 18Z SATURDAY/...
Issued at 115 PM EDT Fri Aug 16 2024

An upper low rotating through the western Great Lakes will
continue to bring showery periods to the area this weekend. Rain
has exited to the northeast for the time being, but abundant
low-level moisture is allowing MVFR ceilings to persist. Widely
scattered showers and storms may develop again this afternoon
with instability increasing as we warm, but not confident on 
this since best upper level support is well west. Therefore did 
not mention in the forecast but will monitor. CAMS do show some
activity associated with a shortwave moving through NW Indiana 
later this evening, so included VCSH for SBN. 

Ceilings should lift to VFR by this evening, but may fall again
overnight with the passage of the cold front, and there could be
some patchy fog. 

Southwest winds will shift more westerly on Saturday and could
become slightly gusty.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...None.
OH...None.
MI...None.
MARINE...None.

&&

$$

DISCUSSION...Andersen
AVIATION...Cobb

779 
FXUS63 KIWX 161727
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
126 PM EDT Fri Aug 16 2024

.KEY MESSAGES...

- Additional showers and a few thunderstorms possible this
  evening, especially for areas east of I-69.

- Periods of showers and thunderstorms Saturday through Sunday,
  best chances will be in the afternoon/early evening.

- Dry and pleasant next week.

&&

.DISCUSSION...
Issued at 324 AM EDT Fri Aug 16 2024

A convective complex that developed over eastern IA last night
and moved eastward through central/northern IL prompting some
severe thunderstorm warnings mainly due to winds. This cluster has
continued to move eastward early this morning and has weakened
on the northern half of the convective cluster, which will be
the portion that mainly affects the western parts of the CWA
from now through about 10 AM EDT as it moves east through the
remainder of the CWA. Will be monitoring this system as it moves
through as strong winds are still possible with this cluster as
it transits through the area. Current 07z mesoanalysis shows
MUCAPE values around 1000 j/kg moving into northern IN with bulk
shear values around 30 kts along with an influx of moisture
in it's wake which will bring increased dew points with values
into the 70s by later today. The system also is moving fairly 
quickly at about 40 kts. A few strong storms this morning are 
not out of the question however, with a bit more vertical 
resistance should work to keep storms on the weaker side. 

With this complicated pattern the guidance has struggled the
last couple of days and therefore have lower confidence on the
exact evolution through today. Thinking is with this morning's
convection moving through we do get some re-development later
this afternoon ahead of a eastward moving cool frontal boundary.
Due to this mornings convection, the afternoon environment will
be worked over and the convective debris clouds will stick 
around through early afternoon with the moisture influx. The 
question then becomes how much will these aforementioned factors
keep the surface instability at bay and reduce the amount of 
re- development this afternoon, as well as potentially keeping 
any thunderstorms that do develop much tamer than would have 
been otherwise. SPC still has our forecast area mostly under a 
marginal risk, which an isolated severe thunderstorm especially 
east of I-69 is certainly not out of the question later today. 
The main threat with any of the storms remains to be gusty winds
but some small hail will also be possible. Highs today will top
out in the low to mid 80s.

The low pressure center associated with the active weather will
push southeastward and pass just to the north and northeast of
the area. This will keep provide a westerly flow aloft that will
bring a couple of weak impulses through the area bringing
periods of showers and thunderstorms for the entire area on
Saturday into Sunday morning and again on Sunday afternoon when
a northerly flow on the backside of the low pushes in bringing
dry weather along with seasonable temperatures Monday through 
late next week. Will be very comfortable weather with dew points
and low temperatures by Tuesday falling into the 50s.

&&

.AVIATION /18Z TAFS THROUGH 18Z SATURDAY/...
Issued at 115 PM EDT Fri Aug 16 2024

An upper low rotating through the western Great Lakes will
continue to bring showery periods to the area this weekend. Rain
has exited to the northeast for the time being, but abundant
low-level moisture is allowing MVFR ceilings to persist. Widely
scattered showers and storms may develop again this afternoon
with instability increasing as we warm, but not confident on 
this since best upper level support is well west. Therefore did 
not mention in the forecast but will monitor. CAMS do show some
activity associated with a shortwave moving through NW Indiana 
later this evening, so included VCSH for SBN. 

Ceilings should lift to VFR by this evening, but may fall again
overnight with the passage of the cold front, and there could be
some patchy fog. 

Southwest winds will shift more westerly on Saturday and could
become slightly gusty.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...None.
OH...None.
MI...None.
MARINE...None.

&&

$$

DISCUSSION...Andersen
AVIATION...Cobb