768
FXUS63 KIND 172237
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
637 PM EDT Tue Sep 17 2024

.KEY MESSAGES...

- Mostly sunny with RH values dropping to around 20-30% again on
  Wednesday.
- Hot and dry weather through Friday.
- Not as warm and rain chances starting Sunday.

&&

.SHORT TERM (This evening through Wednesday)...
Issued at 300 PM EDT Tue Sep 17 2024

Satellite imagery shows high cloud cover spreading westward into
Indiana, associated with a low pressure system located over the
southern Appalachians. High clouds are expected to remain present
through the night, though little in the way of additional westward
propagation is likely.

Otherwise, mid-level ridging along with surface high pressure remain
the determining factors for our weather. Generally clear skies,
light winds, and low humidity should allow good radiational cooling
tonight. Some ground fog is possible by morning, but a mainly dry
atmosphere will prevent this from becoming widespread.

Tomorrow should shape up to be quite similar to today, albeit with a
slight increase in low-level moisture from increased easterly flow.
This may lead to greater coverage of diurnal cumulus during the
afternoon hours. While moisture is a bit higher, RH values should
still dip into the upper 20s or lower 30s (percent). Light winds
should limit fire weather concerns for the most part.

&&

.LONG TERM (Wednesday night through Tuesday)...
Issued at 300 PM EDT Tue Sep 17 2024

There is some hope that central Indiana could receive some rainfall
starting late this weekend as an upper system and an associated
frontal system approaches from the west while the persistent ridge
weakens and moves to the east. That said, confidence is not high on
timing and coverage as the models diverge with the strength and
timing of the upstream disturbance and related fronts. This is
evident in LREF 500 millibar clustering late weekend into next week
displayed through DESI. DESI total rainfall probability of more than
a half an inch of total rain through Tuesday is currently 20-30
percent. However, with such low confidence in timing and coverage,
could see this probability changing quite a bit as we get closer to
the weekend. Prior to Sunday, look for the ridge to continue to
result in broad subsidence and combine with a mostly dry column per
Hi-Res soundings to result in continued very warm and dry weather.

&&

.AVIATION (00Z TAF Issuance)...
Issued at 637 PM EDT Tue Sep 17 2024

Impacts:

- None.

 Discussion:

VFR conditions are expected through the period.

Winds will become light and variable at most sites overnight, but
return to east-northeast at 10kt or less on Wednesday.

Even with the dry conditions, there is an outside chance of ground
fog late tonight at the outlier sites, especially KLAF.

Otherwise, mainly some high clouds will be around tonight into
Wednesday morning. A few cumulus or mid cloud may reach KIND/KBMG
Wednesday afternoon.

&&

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

$$

SHORT TERM...Eckhoff
LONG TERM...MK
AVIATION...50