350
FXUS63 KIND 090209
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
1009 PM EDT Tue Oct 8 2024

.KEY MESSAGES...

- Isolated areas of upper 30s tomorrow morning

- Above normal temperatures will be common mid to late week, before
colder air moves in early next week.

- Other than a few isolated showers on Sunday, dry weather will
  continue.

&&

.FORECAST UPDATE...
Issued at 1009 PM EDT Tue Oct 8 2024

Forecast is pretty on track with only minor adjustments needed.
Given another night of clear skies and light, variable winds,
temperatures will again drop to the 40s with a few spots potentially
getting to the upper 30s. Coldest temps will be in low lying areas
and can`t rule out isolated spots of light frost forming overnight
but confidence is low. Dew points will be slightly higher than
the past few nights so also can`t rule out isolated spots of
ground fog forming.

&&

.SHORT TERM (This evening through Wednesday)...
Issued at 248 PM EDT Tue Oct 8 2024

Benign Autumn weather continues for Central Indiana as high pressure
remains the dominant weather influence through the week.

Current surface observations show the high pressure centered over
Central and Southern IL. This has lead to light northwesterly
winds this afternoon. Continued subsidence within the high
pressure regime has allowed for surface layer drying with
widespread dewpoints in the mid 30s this afternoon.

High pressure will continue to build eastward over the next 24 hours
with high levels of confluence aloft in the entrance of an upper
level jet. This will lead to weakening winds overnight allowing
for quick PBL decoupling and surface temperatures in the upper 30s
to low 40s tonight. In general, frost isnt expected tonight, but
isolated elevated areas in NW central Indiana could see some light
frost if temperatures reach 37/38F.

Much of the same conditions are expected tomorrow with light
westerly winds on the northern edge of the High and mostly clear
skies beneath subsidence. A slight uptick in surface temperatures
is likely given a weak push of warmer 850-700mb air. Current
expectation is for highs in the mid 70s.

&&

.LONG TERM (Wednesday night through Tuesday)...
Issued at 248 PM EDT Tue Oct 8 2024

A generally stagnant weather pattern will continue for the rest of
the week with dry conditions and seasonable temperatures. The
expansion south of an upper level low from James Bay will enable the
passage of low pressure and an associated cold front this weekend.
Behind this system...some of the coolest air so far this fall will
expand across the region early next week as an upper level trough
amplifies.

Wednesday Night through Friday Night

Surface high pressure will remain the dominant influence across the
Ohio Valley and Great Lakes through the end of the week with dry
conditions...mostly clear skies and generally superb weather
continues. A weak backdoor cold front will slip southwest across the
area late Wednesday into Wednesday night with winds shifting to the
northeast. This will bring a renewed surge of slightly cooler air
for Thursday with highs falling back into the low and mid 70s over
most of the forecast area.

The broad ridge aloft will expand back east into the area for late
week with the surface high drifting into the central Appalachians.
This will promote a return S/SW flow that will boost highs on Friday
back into the 75 to 80 degree range. There will remain an elevated
risk for fire danger Thursday and Friday afternoons with minimum RH
values likely down in the 25-30% range. Wind gusts will be greater
on Friday as central Indiana resides between the departing surface
ridge and an approaching cold front.

Saturday through Tuesday

It will remain warm on Saturday as the aforementioned frontal
boundary drops into the forecast area but this feature will serve as
the transition to a cooler regime that takes root by early next
week. Moisture return ahead of the front is paltry and while a stray
shower cannot be entirely ruled out late Saturday into Sunday...the
prospects of seeing any rain are very low. The much bigger impact
from the passage of the front and the surface wave riding along it
Saturday night will be to advect much cooler air in its wake that
will begin to be noticed on Sunday before bottoming out early next
week as a sharp upper trough amplifies over the eastern U S. Low
level thermals are supportive of highs primarily in the upper 50s
and low 60s. The first true potential for frost this fall appears to
be growing for early next week as well.

&&

.AVIATION (00Z TAF Issuance)...
Issued at 734 PM EDT Tue Oct 8 2024

Impacts:

 - None

Discussion:

VFR conditions and clear skies are expected throughout the period.
Winds will be light and variable tonight and into tomorrow morning
but have included the predominate NW/W direction in the TAFs. Winds
will pick back up slightly for midday to afternoon tomorrow of 4-7
kts with a NW direction.


&&

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

$$

UPDATE...KF
SHORT TERM...Updike
LONG TERM...Ryan
AVIATION...KF