528
FXUS63 KPAH 201111
AFDPAH

Area Forecast Discussion
National Weather Service Paducah KY
611 AM CDT Sun Jul 20 2025

.KEY MESSAGES...

- Heat indices will top out from 105 to 110 throughout the Quad
  State today. Southwest portions of the region are in an
  Extreme Heat Warning due to 4 previous days of similar
  conditions, and the remainder of the region is in a Heat
  Advisory.

- The interstate 64 corridor is in a Flood Watch tonight through
  Monday. After a mostly dry day today, showers and
  thunderstorms with heavy rainfall are expected to increase
  across the Evansville Tri State tonight and especially Monday.

- Dangerous heat and humidity will continue through the work
  week, and possibly into next weekend. Heat indices of 105+ are
  expected each day.

&&

.DISCUSSION...
Issued at 304 AM CDT Sun Jul 20 2025

It looks like today may actually be mostly dry across the Quad
State, but we will have to watch convection developing northwest
of St Louis. There is a surface boundary that runs from west
central Illinois southeast to the I-64 corridor, and it would
not be surprising if some convection moves/develops along that
boundary and into areas that were hit with heavy rainfall and
flooding yesterday. Given that recent very heavy rainfall, a
Flood Watch has been issued from Jefferson and Hamilton counties
eastward through southwest Indiana. Since guidance is in
reasonable agreement in keeping any organized convection north
of the Quad State today, the Flood Watch will begin this evening
and run through 7 PM Monday. If that boundary lights up we will
need to speed up the begin time of the Watch.

If we do indeed stay dry today, the entire area should have no
problem reaching 105+ heat indices this afternoon. A few
isolated areas may reach 110. A Heat Advisory and Extreme Heat
Warning cover the entire region. The Warning is for areas that
have exceeded 105 for at least 4 days. Collaborative restraints
have kept us from adding more of west Kentucky to the warning
today.

Convection tonight into Monday will likely leave a surface
boundary draped across the region into Tuesday, resulting in a
decent coverage of convection both days east of the Mississippi.
Therefore, confidence is not great enough to consider heat
headlines in that region beyond today. In southeast Missouri,
heat indices are likely to continue to hit 105+ through at least
Friday. Hopefully, the day shift will be able to extend the Heat
Warning for southeast Missouri at least through Thursday to
match up with the rest of Missouri. The one concern for
southeast Missouri is mixing depth. There are signs that mixing
depth could exceed 6kft which would likely mix dewpoints down
into the lower 70s or upper 60s. This would be accompanied by
higher temperatures, but heat indices could stay below 105,
especially over the Ozark Foothills.

The 00Z guidance seems a bit weaker with the 500mb high, but
still has it overhead on Wednesday, which could be dry
throughout the area. However, it looks like convection will be a
potential concern again beginning Thursday and on through next
weekend.

&&

.AVIATION /12Z TAFS THROUGH 12Z MONDAY/...
Issued at 611 AM CDT Sun Jul 20 2025

Southwest winds will pick up with mixing this morning and may
gust to around 15kts at times this afternoon. TSRA chances
should hold off until sometime tonight and they should be
limited to KMVN and KEVV. There should be enough wind tonight to
prevent any significant fog formation.

&&

.PAH WATCHES/WARNINGS/ADVISORIES...
IL...Heat Advisory from noon today to 8 PM CDT this evening for
     ILZ075>078-080>087-090-091.
     Flood Watch from this evening through Monday evening for
     ILZ075>078-082-083.
     Extreme Heat Warning until 8 PM CDT this evening for ILZ088-
     089-092>094.
MO...Extreme Heat Warning until 8 PM CDT this evening for MOZ076-
     086-087-100-107>112-114.
IN...Heat Advisory from noon CDT /1 PM EDT/ today to 8 PM CDT /9 PM
     EDT/ this evening for INZ081-082-085>088.
     Flood Watch from this evening through Monday evening for
     INZ081-082-085>088.
KY...Heat Advisory from noon today to 8 PM CDT this evening for
     KYZ007-010>022.
     Extreme Heat Warning until 8 PM CDT this evening for
     KYZ001>006-008-009.

&&

$$

DISCUSSION...DRS
AVIATION...DRS