978
FXUS63 KIWX 281035
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
635 AM EDT Tue May 28 2024

.KEY MESSAGES...

- Cool conditions with periodic showers and a few afternoon
  thunderstorms will continue through Wednesday.

- Severe weather is not expected but a few storms may produce
  small hail and gusty winds during the late afternoon and
  evening today. The best chances for strong storms will be west
  of Highway 31.

- Dry weather is expected Thursday and Friday but more rain
  returns early Saturday and into next week.

&&

.DISCUSSION...
Issued at 303 AM EDT Tue May 28 2024

Large negative height anomaly remains over the Great Lakes and
eastern Canada through the next two days. Multiple vorticity maxima
will rotate through the area during this time, leading to a
continuation of relatively cool and cloudy conditions with periodic
showers. One such vort max (currently a fairly potent one as seen on
latest water vapor imagery) will swing through our area during the
early morning and shear out a bit. This will support expanding
clouds and showers (a process already occurring at press time)
though unfavorable (stable) diurnal timing and overall modest
forcing will keep showers scattered. There is then likely to be a
lull in shower coverage around midday with a brief period of
shortwave ridging in between troughs. This will be our best chance
for more widespread sun but suspect at least some clouds to linger.
This break will be very brief as another vort max approaches during
the late afternoon/evening with increasing shower coverage once
again. This will probably be our most widespread round with
favorable diurnal timing and good midlevel CVA. A few thunderstorms
are possible but instability appears meager. Shear is also very
limited in our area and any storms that do develop have a very low
chance of becoming severe. However, steep midlevel lapse rates and
cold temps aloft yield some low potential for small hail and perhaps
some isolated gusty winds. The best chances will be in our far west
as reflected in the latest SWODY1. Highs today will be similar to
yesterday though a bit warmer in our NE half. Anticipate highs to
top out around 70F to low 70s.

Moist, cyclonic flow continues overnight into Wed and will maintain
chances for SCT showers with perhaps an isolated afternoon storm.
Winds back to a more northerly direction on Wed and this will keep
highs in the mid/upper 60s. Dry air advection and subsidence build
across the area Wed night but models now show yet another trough
swinging through the lower Great Lakes on Thu. Will hold Thu dry for
now given strong negative theta-e advection and eastward
displacement of best forcing but a widely isolated afternoon shower
is not impossible. More sun is anticipated and this will add a few
degrees to the highs despite continued northerly flow.

Sharp midlevel ridge finally moves into our region Thu night/Fri.
However highly amplified and progressive mid/upper level pattern
will yield another trough passage Fri night/Sat. Midlevel CVA and
low level moisture advection will support numerous showers but
forcing weakens with time and instability appears limited especially
given very poor diurnal timing. A brief break late Sat into Sun but
more rain chances arrive late Sun into Mon as active pattern
continues. Highs slowly climb back to near/slightly above seasonal
averages through the period.

&&

.AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/...
Issued at 628 AM EDT Tue May 28 2024

Predominantly VFR to MVFR conditions at the TAF sites, with
brief drops to IFR possible during any heavier showers or
storms. We`ll have chances for showers and thunderstorms
associated with two shortwaves-one this morning, and the other
late this afternoon into the overnight hours. The first is
already impacting KSBN (-shra vcts), but KFWA not as certain as
to impacts. The terminal is on the border between clearing to
the south and wave to the north, with scattered cloud cover at
the moment. Model guidance is all over the place with the
precipitation chances, but given showers are already forming
just north of KFWA opted to add VCSH for now and then as we get
towards 14z we can expect more thunder chances. Second wave
arrives later today-after 21z most likely (closer to 00z is more
favorable). Behind the second wave, KSBN may end up dropping to
MVFR (potentially IFR) ceilings around 6z or so, and expect the
next taf issuance will depict similar trends for KFWA.

&&

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

&&

$$

DISCUSSION...AGD
AVIATION...MCD