621
FXUS63 KIND 020626
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
226 AM EDT Sun Jun 2 2024

.KEY MESSAGES...

- Scattered showers overnight

- Warmer next week with periodic thunderstorm chances. The best
  chances will be Tuesday and Wednesday

&&

.FORECAST UPDATE...
Issued at 948 PM EDT Sat Jun 1 2024

Widespread rain continues to move away from the region to the
northeast this evening with pockets of showers continuing ahead of
the surface low located across southern Illinois. Low stratus had
settled in across the forecast area making for a damp...cool evening
as temps are in the low and mid 60s as of 0130Z.

The low will track into the lower Wabash Valley towards daybreak
with a surface trough attached to the low moving into the region.
While the bulk of the deeper lift has departed the region...the
presence of the low and trough in the area will maintain scattered
showers across much of the forecast area through the night. With
virtually no instability present...have removed any mention of
thunder for the overnight.

With moisture becoming trapped beneath a shallow inversion...expect
patchy fog to develop overnight in addition to the lower stratus.
Temperatures are not likely to move much from current reading
through the night.

Zone and grid updates out.

&&

.SHORT TERM (This evening through Sunday)...
Issued at 224 PM EDT Sat Jun 1 2024

Radar was showing widespread showers lifting north across all but
the very far eastern parts of central Indiana within an area of
isentropic lift on the 305K surface. Hi-Res soundings and
condensation pressure deficits suggest far eastern sections will
also soon saturate down soon supporting 80% plus PoPs for the
remainder of the afternoon.

An upper trough will move to the east of the area tonight and a
ridge will build in in its wake. In addition, a surface system will
move across the Ohio Valley and Great Lakes. As this occurs, the
showers will decrease in coverage and end from west to east with
perhaps a few morning showers lingering over far southeastern
sections.

Hi-Res soundings showing a saturated boundary overnight and weak
surface pressure gradient supports light to calm winds. This will
likely lead to low stratus and or fog.

Soundings and ridging suggest there will be breaks in the cloud
cover Sunday afternoon which should lead to temperatures bouncing
back to the upper 70s and lower 80s. Meanwhile, the low clouds
and fog suggest temperatures will not fall much further than the
lower 60s.

&&

.LONG TERM (Sunday night through Saturday)...
Issued at 224 PM EDT Sat Jun 1 2024

Sunday Night Through Tuesday.

Quiet weather is expected for Sunday night into Monday with a brief
period of upper level ridging ahead of a fairly active week of
showers and thunderstorms. Late Sunday night an MCS is expected to
initiate across the Central Plains and push into Iowa and Missouri
towards Monday morning but this complex will dissipate before even
arriving into Illinois but convective debris from the system is
expected to reach the western counties Monday morning.  An outflow
boundary associated with this system may push as far as Indiana but
that will be dependent on how far the MCS is able to push into Iowa.

This scenario would allow for some convective initiation late
Monday, but this looks to be the unlikely scenario with storms most
likely staying to the west of the forecast area. The next round of
thunderstorms is expected to initiate across Kansas Monday night
with this system having a better chance but still unlikely to impact
portions of western Indiana.

Wednesday Through Saturday.

Broad troughing is expected towards the middle and and of the week
with weather being heavily influenced by residual outflow boundaries
from the thunderstorms earlier in the week which keeps confidence in
precipitation timing and chances fairly low. Towards the end of the
week there is better model agreement in a much stronger upper level
trough across the Great Lakes region bringing more robust
northwesterly flow at the surface and aloft which will bring cooler
conditions into the weekend.

&&

.AVIATION (06Z TAF Issuance)...
Issued at 226 AM EDT Sun Jun 2 2024

Impacts:

- Poor flying conditions through daybreak
- IFR flight conditions will slowly improve to VFR midday

Discussion:

Stagnant airmass overhead has allowed the nearly saturated moist
layer to become baggy and sink towards the surface. This has
resulted in some lingering sprinkles or mist along with a shallow
stratus layer that is within a few hundred feet of the surface.
Guidance suggests that the shallow stratus may become in contact
with the surface with fog otherwise being observed, but some
guidance indicates the fog may only be scattered to perhaps patchy.
The KIND VWP is still indicating some largest aloft at 10 kts, which
could be enough friction to inhibit fog development, but the
question is what will occur in the next few hours. Have a few points
seeing fog development with VSBY down to around 3sm, but this may
need to be adjusted should VWP begin to show nearly calm conditions
aloft sooner.

Expect after daybreak a slow and steady improvement to the CIGs with
a light northerly flow helping to dry the near surface environment.
This should translate into VFR conditions developing by midday or
perhaps early afternoon.

&&

.IND WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$

UPDATE...Ryan
SHORT TERM...MK
LONG TERM...White
AVIATION...Beach