733
FXUS63 KIWX 290500
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
100 AM EDT Mon Apr 29 2024

.KEY MESSAGES...

- Showers and some thunderstorms will be possible this evening
  into early Monday and again Monday afternoon with gusty winds
  and heavy rain being the main threats.

- Additional chances for showers and thunderstorms expected
  during mid to late week period next week.

- Warm with highs in the 70s through Friday with 80s also
  possible on Thursday.

&&

.DISCUSSION...
Issued at 254 PM EDT Sun Apr 28 2024

The upper low pressure system across the Upper Mississippi Valley
moves northeast into Canada this evening through Monday night.
During which time, it`ll push its moisture stream into the forecast
area tonight. After an afternoon of mostly dry weather, chances for
rain are expected to increase west of IN-31 as it moves east.
However, the surface convergence breaks down, instability only
achieves 500 J/kg of energy, and precipitation amounts in
models lower despite continued push of 1 to 1.5 inch PWATs (1 to
3 SDs above normal) along with 30 kts of effective shear into
the area. As such, will look to keep likely PoPs at best. Then,
as the moisture stream slides east on Monday, the area with the
best chance to see any stronger storms appears to be east of
IN-15 and perhaps even as far east as east of I-69. The 7 C/km
mid level lapse rates depart the area before the afternoon, but
there is some maintenance of the 30 kts of effective shear and
500 J/kg MUCAPE so perhaps a damaging wind gust could be had in
the moist environment. Shear appears to have some tendency of
both boundary-parallel and -perpendicular flow owing to
individual cells and perhaps some linear segments as well. With
the MBE vectors going into the inner circle perhaps there could
be some back building or slow moving cells to allow for a heavy
rain allotment with its convective component. Upper divergence
appears to return to southeast after 00z Monday night, which
could also support the heavy rain component. The moisture stream
slides out of the area for Tuesday allowing for a drier day
with sunshine to be observed, especially during the afternoon
for eastern areas. Highs still reside in the 70s Monday and
Tuesday.

Tuesday night into Wednesday morning, a deepening progressive, but
slightly negatively tilted area of vorticity swings into the
Northern Great Lakes, forcing dissipates as precipitation approaches
from the west, so will continue with the dry forecast for Wednesday.
Additional ridging continues to build in the southeast CONUS
Wednesday through Thursday night continuing the dry streak for
the area. It won`t be until Friday that we have another chance
to see more rain as a cold front comes through. Timing is in
question especially as it pertains to if we can receive a
convective component. Next weekend looks cooler with highs in
the 60s. Saturday leans drier than Sunday, but Sunday`s chance
for rain is on the low side as well.

&&

.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 1257 AM EDT Mon Apr 29 2024

A weak cold front will bring rain and a few embedded
thunderstorms to the area today. Rain and thunderstorms can be
seen on radar off to the west over Central Illinois. This
activity will arrive to KSBN between 09-12Z and to KFWA around
12Z. Scattered light showers are likely to persist through much
of the day as the cold front works its way slowly through the
area. Ceilings should drop within the next few hours at both
terminals, with near MVFR ceilings with the onset of
precipitation. Winds will be gusty once again today up to 25
kts. VFR conditions return after 00-03Z by the end of the TAF
forecast period.

&&

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

&&

$$

DISCUSSION...Roller
AVIATION...Johnson