259
FXUS63 KIWX 131021
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
621 AM EDT Mon May 13 2024

.KEY MESSAGES...

- Showers and scattered storms arrive late today and persist
  Tuesday.

- Short break in the rain with dry weather Wednesday night and
  early Thursday followed by more chances for showers and storms
  through the weekend.

- Very warm Sunday with highs around 80, possibly reaching the
  mid 80s.


.DISCUSSION...
Issued at 335 AM EDT Mon May 13 2024

Mild but relatively dry low level flow early today at the onset will
become slightly more moist later today. Weak upper support and very
weak fgen/low level convergence was just enough to trigger/support
isolated showers/storms north of the Michigan border. High resolution
models/CAMs were having a hard time picking up this activity. Expect
the showers and isolated storms will move out of the area before
daybreak.

An upper level system had moved out of Colorado over the weekend and
was over Kansas early this morning. This upper low will drift east
ahead of an increasing moist environment. Precipitable water values
will rise to around 1.40". Very limited instability and lack of
low level shear will greatly limit any severe storm risk. The
activity should arrive late today and early tonight and persist
through Tuesday. A second upper level system will arrive later
in the week and bring additional chances for showers and storms
in generally the same environment of high precipitable water
values, low CAPE and limited shear. Locally heavy rain is likely
at times which will bring rises on rivers and possibly bring a
few of the more flashy rivers into action stage or minor flood
stage like North Manchester, Portland and Spy Run. The latest
OHRFC ensemble river forecasts using the GFS model favor several
rivers exceeding the action stage by late Sunday. Otherwise,
did raise blend highs for Sunday to around 80 with the potential
for highs to reach the mid 80s supported by the EC and GFS.

&&


.AVIATION /12Z TAFS THROUGH 12Z TUESDAY/...
Issued at 610 AM EDT Mon May 13 2024

Breezy conditions today after 18z Mon with gusts of 15-20 kts
possible at least through 00z Tue ahead of a low pressure
circulation that will move into the area. Have introduced rain
and periods of thunderstorms after 18z Mon for both TAF sites.
MVFR conditions with vsbys during the heavier rain/thunderstorms
dropping to around 4SM. After 06z Tue for KSBN will see cigs
drop to IFR for that site at this time KFWA looks to remain MVFR
in both cigs/vsbys after 08z Tue.

&&

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

&&

$$

DISCUSSION...Skipper
AVIATION...Andersen