473 
FXUS63 KIND 090801
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
301 AM EST Sat Nov 9 2024

.KEY MESSAGES...

- Rain expected tonight into Sunday.

- Above normal temperatures will likely continue through Wednesday
  but near normal temperatures could return late next week.

- Chance for light rain late Wednesday into early Thursday.

&&

.SHORT TERM (Today and tonight)...
Issued at 301 AM EST Sat Nov 9 2024

Today, upper ridging along with surface high pressure will gradually 
slide east of the area. Dry air in the lower levels will linger with 
some influence from high pressure remaining.

Moisture aloft will increase with southwesterly flow on the back 
side of the retreating upper ridge and ahead of a deepening upper 
low. Clouds will thicken and lower during the day. Some weak lift in 
the mid levels will try to bring some rain to mainly western 
portions of the area this afternoon, but the dry low levels should 
prevent this from reaching the ground.

There should be enough sunshine to help temperatures reach the lower 
60s across much of the area this afternoon.

Tonight, as the upper low moves into the Upper Mississippi Valley, a 
40-50kt 850mb jet will move into the area. Moisture will flow 
northward from the Gulf of Mexico, with the potential for some 
limited moisture from Tropical Cyclone Rafael to be brought north as 
well. Precipitable water values will be approaching climatological 
maximum for this time of year. 

At the surface, a warm front will move north into the area tonight. 
Central Indiana will also be influenced by an upper jet streak. 
These will produce additional forcing. The expected forcing and 
moisture will bring rain to the entire area, so will go high PoPs 
all locations tonight. 

Some uncertainty remains on rainfall amounts, as convection to the 
south of the area may rob some from our area. Ensembles are focusing 
the highest precipitation totals to south of the Ohio River. HREF 
local probability matched means do show the potential for local 
amounts over an inch by 12Z Sunday, but most ensemble members keep 
the area at half an inch or less. These lower amounts seem 
reasonable given convection to the south of the area.

Speaking of convection, some low MUCAPE values do reach central 
Indiana tonight, so will continue to mention an isolated 
thunderstorm possible. 

Southerly winds and the warm front will keep temperatures 
unseasonably warm tonight, with lows in the upper 40s to middle 50s 
expected. The values in the middle 50s are not far off from record 
high minimums for November 10. (However, colder air moving in Sunday 
evening should keep any records from being set).

&&

.LONG TERM (Sunday through Friday)...
Issued at 301 AM EST Sat Nov 9 2024

A deepening low pressure system and associated cold front is 
expected to be moving through the region at the start of the period. 
Favorable dynamics combined with anomalous moisture return from the 
gulf will likely support widespread beneficial rainfall. The 
heaviest precipitation from the system should fall before daybreak 
Sunday during the short term period. That being said, most locations 
across central Indiana are likely going to receive an additional 0.1-
0.25 inches of rainfall on Sunday. Model guidance shows very weak 
instability suggesting thunder is unlikely.

Expect surface high pressure to begin building in late Sunday as the 
aforementioned system shifts east. This will allow dry conditions to 
return along with less cloud cover to start the work week. Cold air 
advection on the backside of the departing low should provide 
slightly cooler temperatures, but highs are likely to remain 
seasonably warm. 

Another upper trough approaches the region by the middle of next 
week. Ensembles generally show a low-moderate chance for very light 
precipitation with this system. QPF amounts will be limited greatly 
due to a lack of moisture return as ridging remains dominant over 
the Gulf Coast. There is good agreement in the ensembles that a more 
significant cooldown is likely which may help return temperatures to 
near normal. However, guidance shows anomalous riding building back 
in after the cooldown. This could once again lead to abnormally warm 
temperatures in the 8-14 day period.

&&

.AVIATION (06Z TAF Issuance)...
Issued at 1213 AM EST Sat Nov 9 2024

Impacts:

- Low chance of fog overnight, mainly at KLAF
- For KIND 30 Hour TAF, MVFR and worse after 06Z Sun

Discussion:

For much of the period, high and then mid clouds will gradually 
increase across the sites. The high clouds and light winds should 
prevent fog formation, but cannot rule it out, especially at KLAF.

A few wind gusts near 20kt are possible this afternoon.

MVFR ceilings may sneak into KHUF near 06Z Sunday, then spread 
northeast into the KIND area before 12Z Sunday. Rain will accompany 
the lower ceilings.


&&

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

$$

SHORT TERM...50
LONG TERM...Melo
AVIATION...50