346 
FXUS63 KIND 020656
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
256 AM EDT Wed Oct 2 2024

.KEY MESSAGES...

- Patchy fog possible tonight, especially south and east of 
  Indianapolis.

- Largely dry conditions with near to above normal temperatures 
  through the weekend

&&

.SHORT TERM (Today and tonight)...
Issued at 255 AM EDT Wed Oct 2 2024

Surface high pressure is moving into the region behind yesterday's 
cold front. Dry continental polar air has replaced the muggy air 
mass we've been stuck in for the past week. Temperatures are already 
almost 15 degrees cooler than the previous night. With diminishing 
winds and mainly clear skies, excellent radiational cooling 
potnetial is anticipated. However, this may not persist entirely 
through the night as high cirrus are advancing southeastward into 
Indiana as of this writing. Nevertheless, lows well into the 40s are 
expected by morning.

Any lingering cirrus should diminish shortly after sunrise, leaving 
us with clear skies. Model soundings show a dry column which should 
limit diurnal cumulus formation. As the core of high pressure 
settles in, winds are likely to go light and variable for much of 
the afternoon. With clear skies and very light winds...today's highs 
near 70 should feel quite nice.

Tonight will feature ideal radiational cooling conditions yet again, 
though winds may take on a very light southerly component. Lows in 
the 40s are again expected. Boundary layer saturation by Thursday 
morning may allow for some fog to develop, especially in the 
southeastern half of our CWA. Fog should be mostly shallow and 
confined to open areas and river valleys, but a few pockets of dense 
fog cannot be ruled out.

&&

.LONG TERM (Thursday through Tuesday)...
Issued at 255 AM EDT Wed Oct 2 2024

After the cooler and wetter pattern experienced over the last 
several days initiated by the remnants of Helene...the pattern is 
reverting back to a largely dry and seasonably warm regime that will 
continue through the weekend. 

An elongated and flattened upper ridge will hold largely to our 
south through the end of the week prior to expanding into the region 
for the first half of the weekend ahead of a sharp upper trough 
traversing the U S-Canada border. At the surface...the Ohio Valley 
will remain under high pressure with two brief exceptions as cold 
fronts pass through Friday and again on Sunday afternoon. 

With the Gulf of Mexico cutoff courtesy of easterly flow...neither 
boundary will have much moisture to work with. The Friday front is 
the weaker of the two with a subtle increase in mid and high clouds 
and a wind shift signaling the passage of the boundary. The Sunday 
front is stronger and has better upper level support from the trough 
referenced above moving along the Canadian border. The primary 
mitigating issue for precipitation besides the lack of low level 
moisture is that the upper level forcing will be displaced well to 
the north of the region. While the strength of the front alone could 
generate a few showers with passage Sunday afternoon...cannot 
justify higher than slight chance pops at this time considering the 
limiting factors.

Highs will be seasonable to start on Thursday in the mid 70s...then 
rise into the upper 70s and lower 80s by the weekend in advance of 
the Sunday front. Strong cold advection in wake of the late weekend 
boundary and a renewed surge of drier air will set the stage for 
cooler days early next week in the upper 60s and lows that will 
likely fall as low as the lower 40s. 

In the 7-10 day range...signals support the expansion of a broader 
upper level ridge from the western part of the country which would 
support highs returning into the mid to perhaps upper 70s late next 
week. The dry pattern will continue as well with no threat for rain 
anticipated at all next week.

&&

.AVIATION (06Z TAF Issuance)...
Issued at 138 AM EDT Wed Oct 2 2024

Impacts:

- None.

Discussion: 

VFR conditions are expected.

Winds are beginning to diminish and should stay under 10kt at all 
terminals through the forecast period. Direction may go light and 
variable as surface high pressure settles in. A light southerly flow 
may develop after sunset.

High cirrus should persist through the night, but diminish quickly 
around sunrise. A dry lower atmosphere should limit diurnal cumulus 
growth this afternoon.

There is a low probability of shallow overnight fog, especially LAF, 
HUF, and BMG. Better chance for fog is Wednesday night compared 
to this morning.


&&

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

&&

$$

SHORT TERM...Eckhoff
LONG TERM...Ryan
AVIATION...Eckhoff