766 
FXUS63 KLMK 111443
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
1043 AM EDT Thu Jul 11 2024

.KEY MESSAGES...

*   Mostly dry weather and warming temperatures expected for Friday 
    through early next week. Worsening drought conditions are 
    possible.

*   Triple-digit heat index values could return Sunday afternoon and 
    are likely early next week.

&&

.UPDATE...
Issued at 1043 AM EDT Thu Jul 11 2024

Skies are mostly sunny this morning, and temperatures are now 
approaching 80 degrees. A compact upper level shortwave trough is 
spinning east across IL. Morning SDF ACARS soundings show a 
significant warm layer near 600 mb, which will limit instability and 
any potential convective growth. With very light, somewhat chaotic 
low-level flow in place, the next several hours continue to look dry 
with temperatures warming into the upper 80s/near 90 this afternoon. 

As we move into the evening hours, weak low-level convergence and 
moisture pooling over the Lower Wabash should yield spotty 
convection. Isolated storms may be able to drift into our southern 
IN counties through the late evening hours. Cannot rule out a brief 
heavier shower in the northwestern CWA. Otherwise, dry conditions 
are likely to continue.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 322 AM EDT Thu Jul 11 2024

Skies are clear this morning thanks to sfc high pressure to our 
north building in over the region today. Still could see patchy fog 
develop in the predawn hours, especially in valley locations. Fog 
will mix out after sunrise and with the sfc high we will have mostly 
sunny skies through most of the day. Upper heights will gradually 
increase over the region allowing for temperatures to be warmer than 
they were yesterday by a few degrees. Highs will be in the upper 80s 
with a few locations reaching 90 by the afternoon. 

Even with gradually increasing heights, a weak shortwave trough will 
work through Indiana as it moves to the northeast. A few embedded 
vort maxes associated with this system will mainly work across 
Indiana but could be enough lift to develop a few isolated 
showers/storms across southern IN. Going with a general 15-25 
percent chance of precipitation this afternoon before diminishing 
this evening given the diurnal nature of the activity. Mid-level 
inversion around 600mb will keep mid-level lapse rates low and be 
enough of a cap to keep most of the activity on the Indiana side. 

Skies will become clear again overnight with additional development 
of some fog, again in mainly low lying areas overnight. With the 
warmer temperatures and increased dew points, lows will be in the 
mid/upper 60s with more urban locations in the low 70s.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
Issued at 322 AM EDT Thu Jul 11 2024

Weak upper trofiness will linger over the Great Lakes Friday into 
Saturday, allowing for waves of convection to possibly brush 
southern Indiana each day.  Friday afternoon appears to be the best 
chance, but even then we're only carrying a 20% chance which barely 
extends south of the Ohio River. Overall heights aloft will be 
starting a slow rise, so temps will trend a couple degrees warmer 
each day, getting solidly above normal by Saturday. Otherwise dry 
weather continues through the weekend, as does the warming trend 
with mid 90s possible by Sunday afternoon, and enough humidity to 
push the heat index close to 100.  

Monday and Tuesday will be the hottest days of the upcoming week for 
at least some of the area, as H8 temps warm to near 23C. This could 
support mid to upper 90s, but the pattern looks active enough to our 
north that convection could create quite a bit of bust potential. 
Pulled back slightly from bullish NBM highs, but it will still be 
hot with most areas solidly in the mid 90s. This will likely push us 
into Heat Advisory territory one or both days, so stay tuned.   

By Wednesday the ridging breaks down enough for increased shower and 
storm chances and "less hot" temperatures.

&&

.AVIATION /12Z TAFS THROUGH 18Z FRIDAY/...
Issued at 647 AM EDT Thu Jul 11 2024

Skies remain clear this morning thanks to sfc high pressure over the 
region today. While current satellite nighttime microphysics imagery 
shows only some isolated spots of fog. Current obs do show only a 
few airports, like HNB, seeing fog this morning. While LEX/BWG are 
not out of the question, confidence is low but if any fog develops 
it should mix out by around 12-13z. The rest of the forecast calls 
for prevailing VFR flight categories with just FEW/SCT mid clouds 
towards the afternoon. Weak upper system will work into IL/IN this 
afternoon and this could spark a few isolated showers and storms 
into souther IN. Went ahead and put vicinity showers for this 
afternoon at HNB but kept the rest dry and that will continue into 
the overnight and tomorrow.

&&

.LMK WATCHES/WARNINGS/ADVISORIES...
KY...None.
IN...None.

&&

$$

UPDATE...EBW
SHORT TERM...BTN
LONG TERM...RAS
AVIATION...BTN