kywx
Kentucky AI Weather Engine

Kentucky AI Forecasting Beta

Mon, Aug 3
Wed, Aug 5
Forecast For

Tuesday, August 4

Updated Aug 4, 7:16 AM EDT

NWS Alerts Active This Day

Special Weather Statement

Aug 4, 5:17 AM -> Aug 4, 10:00 AM
Moderate Severity

Special Weather Statement issued August 4 at 4:17AM CDT by NWS Paducah KY

Confidence
70%

Summer Heat Dominates with Isolated Eastern Drizzle

A strong ridge of high pressure will anchor over the region on Tuesday, bringing hot and mostly dry conditions to the majority of Kentucky. While the western and central parts of the state enjoy full sunshine, a shallow plume of moisture interacting with the eastern mountains will trigger isolated light rain and drizzle, primarily in the afternoon and evening.

Why is this happening?
Technical explanation of the atmospheric setup
Confidence Assessment

Confidence is very high regarding the overall heat and dry conditions for Western and Central KY. However, disagreement between the NAM and global models regarding the western moisture convergence and the spatial extent of eastern drizzle lowers the overall score.

Get Personalized Forecasts

Choose which region in Kentucky you're interested in and we'll always show you that one first. You can change your selected region by clicking the "Star" icon on any regional forecast.

Purchase Area

Paducah, Murray, Mayfield
Morning Clouds Clearing to Sun
Sunny
86°/ 66°

Northwest Pennyrile

Owensboro, Henderson, Morganfield
Breezy and Bright
Sunny
85°/ 65°

Southwest Pennyrile

Hopkinsville, Madisonville, Princeton
Typical August Heat
Sunny
86°/ 67°

Barren River

Bowling Green, Glasgow, Franklin
Mostly Sunny with Stray Clouds
Sunny
86°/ 67°

Louisville Metro

Louisville, La Grange, Shepherdsville
Sunny and Warm in the City
Sunny
88°/ 66°

Lincoln Trail

Elizabethtown, Bardstown, Leitchfield
Sunny and Pleasant Summer Day
Sunny
85°/ 66°

Lake Cumberland

NUISANCE
Somerset, Columbia, Monticello
Afternoon Clouds and Light Drizzle
Rain
87°/ 68°

Northern Kentucky

Covington, Florence, Independence
Clear and Comfortable
Sunny
85°/ 63°

Inner Bluegrass

Lexington, Georgetown, Winchester
Sunny and Warm
Sunny
88°/ 64°

Bluegrass Foothills

NUISANCE
Richmond, Danville, Berea
Passing Clouds and Drizzle
Rain
85°/ 65°

Northeast Kentucky

Ashland, Morehead, Grayson
Hot Sun with Late Clouds
Sunny
88°/ 64°

Southeast Kentucky

NUISANCE
Hazard, Pikeville, Harlan
Light Rain in the Mountains
Rain
84°/ 65°

Possible Outcomes

Weather forecasting involves uncertainty. Below are two scenarios representing the range of possible outcomes: the "Boom" scenario shows the worst-case/highest-impact result if conditions align unfavorably, while the "Bust" scenario shows the best-case/lowest-impact result if the forecast doesn't materialize as expected.

💥

The 'Boom' Scenario

If the mid-level ridge is slightly weaker than modeled, the moisture plume in the east could penetrate further west into the Bluegrass, resulting in more widespread cloud cover and cooler afternoon highs in the low 80s for Central Kentucky.

💨

The 'Bust' Scenario

If the subsidence from the high pressure is maximized, the shallow moisture in the east will evaporate as virga before reaching the ground, leaving the entire state dry and pushing afternoon temperatures toward the lower 90s.

Model Disagreements

When models disagree, a call must be made to determine the most likely outcome. This decision is based on a combination of factors including model performance, historical data, and the models general accounting of each climatic region of Kentucky.

Northeast Compression Heat

The GFS is forecasting a significant heat outlier for the Ashland area, suggesting a high of 93°F due to compression heating, while the NAM and Euro suggest a more moderated 84-86°F.

GFS
VS
NAM
VS
EURO
Why BLEND Wins

While the GFS often captures valley-specific heating, the 93°F mark is a 7-degree outlier compared to the ensemble mean. A weighted blend accounts for the high sun angle while respecting the broader thermal profile.

Affected Regions
NORTHEAST KY

The Purchase Moisture Ghost

The NAM is an outlier, forecasting a period of morning rain (80% PoP) in the far western Purchase region due to mesoscale moisture convergence. The GFS and ECMWF maintain a dry solution, suggesting that strong subsidence from the ridge will suppress this development.

NAM
VS
GFS
VS
EURO
Why EURO Wins

Global models (ECMWF/GFS) are better handling the synoptic suppression from the building ridge. The NAM logic trace admits high bust potential due to subsidence, making the drier solution more probable.

Affected Regions
PURCHASE

Technical Analysis

This section provides a deep, physics-based explanation of the weather. Our AI system analyzed multiple atmospheric layers and variables from all available models to synthesize this technical overview.

Below you'll find detailed breakdowns of the atmospheric dynamics that are driving today's forecast, including thermodynamics, kinematics, and hydrology.

Thermodynamics

Stability & Temperatures

How temperature changes with altitude. This determines whether precipitation falls as rain, snow, sleet, or freezing rain based on the vertical temperature profile.

Thermal Profile Overview

The vertical profile shows a standard summer dry-adiabatic lapse rate in the lowest levels, capped by a weak subsidence inversion around 700mb. In the east, the boundary layer is nearly saturated, while the mid-to-upper levels remain bone-dry.

Thermal Boundary

No significant surface boundaries exist; the primary thermal gradient is a result of terrain-induced cloud cover in the east vs full insolation in the west.

Diurnal Trend

A standard diurnal curve will be observed across most of the state, with non-diurnal fluctuations possible in the Southeast Coalfields where cloud cover and drizzle will flatten the afternoon heating.

Kinematics

Wind & Energy

Wind patterns and atmospheric energy. Frontal passages, jet stream positioning, and vorticity tell us where and when lift will generate precipitation.

Frontal Passage

None. The environment is dominated by a stagnant surface high (approx 1018mb) centered to our northwest.

Jet Stream Support

Neutral support. Kentucky remains in a region of upper-level convergence, which typically promotes sinking air and clear skies.

Energy Status

Weak vorticity peaks are noted in the far southeast, providing just enough lift to facilitate light rain in the mountains.

Hydrology

Moisture & Precipitation

Moisture content and precipitation character. This reveals whether the atmosphere is saturated enough to produce precipitation, and what type to expect (steady vs. bursts).

Saturation Status

Saturated below 850mb in the east; the remainder of the state features dewpoint depressions of 15-20°F at the surface, posing a virga risk.

Precipitation Character

Stratiform and drizzle. The lack of instability (CAPE 0-100 J/kg) precludes any thunderstorm or heavy convective activity.

Flooding Context

No risk. Ground conditions are stable and liquid totals will be negligible (under 0.10 inches).

Celestial Almanac

Moon Phase

Waning Gibbous

67% Illumination
Moonrise
11:29 PM
Moonset
1:14 PM
Purchase Area
Sunrise
7:03 AM
Sunset
9:00 PM
Civil Dawn
6:34 AM
Civil Dusk
9:28 PM
Northwest Pennyrile
Sunrise
6:55 AM
Sunset
8:55 PM
Civil Dawn
6:26 AM
Civil Dusk
9:24 PM
Southwest Pennyrile
Sunrise
6:59 AM
Sunset
8:55 PM
Civil Dawn
6:30 AM
Civil Dusk
9:23 PM
Barren River
Sunrise
6:54 AM
Sunset
8:51 PM
Civil Dawn
6:26 AM
Civil Dusk
9:20 PM
Louisville Metro
Sunrise
6:49 AM
Sunset
8:51 PM
Civil Dawn
6:20 AM
Civil Dusk
9:20 PM
Lincoln Trail
Sunrise
6:50 AM
Sunset
8:50 PM
Civil Dawn
6:22 AM
Civil Dusk
9:19 PM
Lake Cumberland
Sunrise
6:47 AM
Sunset
8:44 PM
Civil Dawn
6:18 AM
Civil Dusk
9:13 PM
Northern Kentucky
Sunrise
6:42 AM
Sunset
8:48 PM
Civil Dawn
6:12 AM
Civil Dusk
9:17 PM
Inner Bluegrass
Sunrise
6:44 AM
Sunset
8:46 PM
Civil Dawn
6:15 AM
Civil Dusk
9:15 PM
Bluegrass Foothills
Sunrise
6:44 AM
Sunset
8:44 PM
Civil Dawn
6:15 AM
Civil Dusk
9:13 PM
Northeast Kentucky
Sunrise
6:36 AM
Sunset
8:39 PM
Civil Dawn
6:07 AM
Civil Dusk
9:08 PM
Southeast Kentucky
Sunrise
6:41 AM
Sunset
8:39 PM
Civil Dawn
6:12 AM
Civil Dusk
9:07 PM

Dive Deeper Into the Models

This forecast is a synthesis of raw data from the NAM, GFS, ECMWF, and GEM models. These models provide detailed atmospheric analyses including 500mb vorticity, precipitation rates, and more. You can take a look at the raw model data by clicking the links below.