textproduct: Paducah

KEY MESSAGES

- Hot temperatures and high humidity will continue through at least Thursday with heat index values up to near 110 degrees. The heat headlines may eventually need to be extended into this weekend with little relief now expected.

- Rain chances begin to return by this evening, peaking at a 40-50% chance Wednesday evening and Thursday evening. The greatest risk will be across northeast portions of the region, while the south may see no rainfall at all.

- There is the potential for a few severe storms, especially on Wednesday. Damaging winds is the main concern.

DISCUSSION

Issued at 110 AM CDT Tue Aug 11 2026

An upper level ridge of high pressure remains in control with a warm sector regime prevailing through the week. High temperatures in the 90s and dewpoints that are once again overachieving in the 70s will yield heat index values up to near 110 degrees through at least Thursday. Model guidance has trended weaker with a cold front that eventually washes out over the FA on Friday. Little relief is now expected that yields heat index values remaining above 100 degrees well into the weekend. As a result, the heat headlines may eventually need to be extended with a 597 dm ridge building over the FA from the south. The height rises fall well in the 99th percentile on the NAEFS for this time of year with 850 mb temps warming to 25C.

Despite the trend for a stronger ridge of high pressure, multiple H5 shortwaves are still progged to round the ridge across the Ohio Valley that will bring rain chances in the vicinity beginning today. The NSSL/NAMNest try to bring in a MCS as early as this morning, but most of the CAMs including the HRRR do not show much convection clipping the northeast until Tuesday evening at the earliest. In fact, Wednesday evening and potentially Thursday evening continue to be when the risk is the greatest for a potential MCS complex with NBM PoPs maxing out around a 40-50%. However, the probability is non- zero for something else to sneak in outside this window at some point.

There remains the potential for stronger storms with a consistent signal to support some severe weather, especially on Wednesday. MLCAPE each day is progged around 2500 to 3500 J/kg by the RAP13. Combined with steep 8-9 C/km sfc-3km lapse rates and DCAPE upwards of 1400 J/kg, damaging winds will be the main concern with any complex of storms that develops. Although the best upper level dynamics are located over the Great Lakes region with a 120 kt jet max, the thermodynamics are more than sufficient to make up the modest deep layer shear in the profile. It is worth noting while northeast portions of the FA may see heavy rainfall, the south may see no rainfall at all. Low rain chances may linger into Friday, followed by dry conditions over the weekend as the aformentioned ridge suppresses additional chances.

AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/

Issued at 510 AM CDT Tue Aug 11 2026

VFR conditions are forecast today with few cu around 3-4 kft AGL developing again during peak heating. SSW winds between 8-14 kts with gusts near 20 kts are expected. The first of several convective complexes will begin to move in the vicinity of the region this evening. There is a PROB30 at KEVV/KOWB for tonight as it is a close call if storms will reach southwest Indiana. Winds after sunset will be south between 4-7 kts.

PAH WATCHES/WARNINGS/ADVISORIES

IL...Heat Advisory until 8 PM CDT Thursday for ILZ075>078-081>094. Extreme Heat Warning until 8 PM CDT Thursday for ILZ080. MO...Heat Advisory until 8 PM CDT Thursday for MOZ076-086-087-100- 107>112-114. IN...Heat Advisory until 8 PM CDT /9 PM EDT/ Thursday for INZ081- 082-085>088. KY...Heat Advisory until 8 PM CDT Thursday for KYZ001>022.