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Kentucky AI Weather Engine

Kentucky AI Forecasting Beta

This is the NAM model's output only

You're viewing raw atmospheric data from the NAM 3km Nest (North American Mesoscale - High Resolution Nest). This is just one model's interpretation and it may disagree with the other models.

Our AI uses this data (along with other models) to create the final forecast. Don't treat this as the definitive answer.

View the Synthesized Forecast Instead

NAM 3km Nest Forecast Data

North American Mesoscale - High Resolution Nest

The high-resolution 'nest' of the NAM system operating on a 3km grid. Unlike the parent model, this is a Convection-Allowing Model (CAM), meaning it explicitly resolves storm updrafts rather than approximating them. It is the primary workhorse for predicting storm mode, squall line timing, and heavy snow bands in Kentucky.

resolution
3km horizontal, 60 vertical levels
domain
Continental United States (CONUS)
update Frequency
Every 6 hours (00Z, 06Z, 12Z, 18Z)
forecast Length
60 hours (2.5 days)
physics
Explicit Convection (No parameterization), Ferrier-Aligo microphysics, MYJ boundary layer
data Assimilation
Hybrid 3DEnVar (Initializing from parent NAM)

Soaking Rain West and Central; Humid Elsewhere

Kentucky will see a split in weather conditions for July 19th. Those in the Western and Central portions of the state should prepare for multiple rounds of rain showers. A significant morning wave will move through the Paducah and Owensboro areas, while another round is expected to develop across the Lincoln Trail and Bluegrass regions by the evening.

Eastern Kentucky and the Northern Kentucky river cities will largely remain dry but very humid. Temperatures across the state will rise into the mid-to-upper 80s, though areas seeing persistent rainfall will likely stay in the 70s through much of the morning and early afternoon.

Why is this happening?
Technical explanation of the atmospheric setup

Regional Conditions

PURCHASE

Paducah, Murray, Mayfield
IMPACTFUL
Condition
Heavy Rain
Heavy Morning Rain
Expect a very wet start to the day with heavy rain moving through during the morning hours. Rainfall totals could approach 2 inches in some areas.
Temperature
High
88°
Low
74°
Feels Like
88°
Precipitation
Chance
80%
Rain
1.5 - 2"
Wind
5 mph

NORTHWEST PENNYRILE

Owensboro, Henderson, Morganfield
Condition
Cloudy
Cloudy and Humid
Mostly cloudy skies will keep things humid, but the most significant rain should stay just to your south and west.
Temperature
High
88°
Low
75°
Feels Like
88°
Precipitation
Chance
10%
Wind
7 mph

SOUTHWEST PENNYRILE

Hopkinsville, Madisonville, Princeton
IMPACTFUL
Condition
Rain
Showers Throughout the Day
Prepare for off-and-on showers starting in the morning and continuing through the early evening.
Temperature
High
87°
Low
71°
Feels Like
87°
Precipitation
Chance
80%
Rain
0.5 - 1"
Wind
7 mph sustained, gusts to 16 mph

BARREN RIVER

Bowling Green, Glasgow, Franklin
NUISANCE
Condition
Rain
Damp and Humid Conditions
Expect some light rain and drizzle throughout the day, though significant accumulation is not expected.
Temperature
High
87°
Low
73°
Feels Like
87°
Precipitation
Chance
80%
Rain
0.05 - 0.15"
Wind
4 mph

LOUISVILLE METRO

Louisville, La Grange, Shepherdsville
Condition
Cloudy
Hot and Muggy Metro
The city will remain dry and cloudy, though the humidity will make it feel much warmer than the actual temperature.
Temperature
High
89°
Low
75°
Feels Like
89°
Precipitation
Chance
10%
Wind
9 mph

LINCOLN TRAIL

Elizabethtown, Bardstown, Leitchfield
IMPACTFUL
Condition
Heavy Rain
Soaking Evening Rainfall
A series of rain showers will culminate in a heavy soaking late in the evening. Total rainfall could exceed 1.5 inches.
Temperature
High
85°
Low
70°
Feels Like
85°
Precipitation
Chance
80%
Rain
1.5 - 2"
Wind
8 mph sustained, gusts to 22 mph

LAKE CUMBERLAND

Somerset, Columbia, Monticello
NUISANCE
Condition
Rain
Scattered Morning Showers
Expect some damp conditions and morning showers, with cloudy skies persisting for the rest of the day.
Temperature
High
84°
Low
73°
Feels Like
84°
Precipitation
Chance
80%
Rain
0 - 0.05"
Wind
6 mph sustained, gusts to 20 mph

NORTHERN KY

Covington, Florence, Independence
Condition
Cloudy
Dry and Overcast
Cloudy skies will prevail, but the rain is expected to stay well to the south.
Temperature
High
80°
Low
73°
Feels Like
80°
Precipitation
Chance
10%
Wind
7 mph sustained, gusts to 16 mph

BLUEGRASS CORE

Lexington, Georgetown, Winchester
NUISANCE
Condition
Rain
Late Evening Showers
A dry day will give way to scattered rain showers late in the evening.
Temperature
High
86°
Low
73°
Feels Like
86°
Precipitation
Chance
80%
Rain
0 - 0.1"
Wind
8 mph

BLUEGRASS FOOTHILLS

Richmond, Danville, Berea
NUISANCE
Condition
Rain
Afternoon Rain Showers
Rain will develop during the afternoon and continue through the evening, with a few heavier bursts possible.
Temperature
High
81°
Low
71°
Feels Like
81°
Precipitation
Chance
80%
Rain
0.1 - 0.3"
Wind
7 mph sustained, gusts to 17 mph

NORTHEAST KY

Ashland, Morehead, Grayson
Condition
Cloudy
Humid and Mostly Dry
It will be a humid and cloudy day, but you can expect to stay dry as the rain stays to the west.
Temperature
High
82°
Low
74°
Feels Like
82°
Precipitation
Chance
10%
Wind
6 mph sustained, gusts to 13 mph

SOUTHEAST COALFIELDS

Hazard, Pikeville, Harlan
Condition
Cloudy
Foggy Start, Cloudy Day
Typical morning fog will lift to mostly cloudy skies. Rain chances remain very low for the area.
Temperature
High
83°
Low
73°
Feels Like
83°
Precipitation
Chance
10%
Wind
5 mph sustained, gusts to 14 mph

Technical Analyses

To generate the forecast, our AI system analyzed multiple atmospheric layers and variables from the NAM model. Each chart below represents a different aspect of the atmosphere—from the jet stream at 30,000 feet down to surface conditions—providing crucial pieces of the weather puzzle.

The AI model extracted key meteorological features from each analysis, identified patterns and conflicts between different atmospheric levels, and synthesized this information into a coherent forecast. For example, surface temperatures might suggest snow, but upper-level warmth could mean rain instead. The model weighs these factors to determine the most likely outcome based on historical precedent.

Below you'll find detailed breakdowns of each atmospheric analysis that contributed to the forecast, including what the model shows and how it influences Kentucky's weather.

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.

Vertical Temperature Stack

The vertical temperature profile is characterized by a moist adiabatic lapse rate with no significant inversions aloft. Freezing levels are situated well above the 700mb level.

Thermal Boundary Location

The entire state is entrenched in a warm, moist maritime tropical (mT) air mass; no distinct freezing line exists within the troposphere.

Diurnal Trend

The diurnal curve will be suppressed in Western/Central KY due to significant cloud cover and precipitation. Non-diurnal temperature trends are possible where heavy rain persists during the morning.

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

No surface frontal passage is noted. The system is driven by a series of weak mid-level shortwave troughs ripples within a broader cyclonic flow.

Jet Stream Support

The right entrance region of a 300mb jet provides large-scale divergence and lift over the Purchase and Lincoln Trail regions.

Energy Status

Moderate vorticity pulses are expected to move through the state in waves, with the strongest peak (0.0007) occurring in Central Kentucky during the late afternoon.

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

The atmospheric column is deeply saturated (RH > 90%) from the surface to 500mb in Western Kentucky, while Eastern Kentucky remains dry aloft.

Precipitation Character

Precipitation will be primarily stratiform with convective elements embedded, particularly in areas of higher terrain where orographic enhancement occurs.

Flooding Context

The ground is not currently saturated, but high rainfall rates (1.5in+) in the Western regions could lead to localized urban drainage issues.

NAM Raw Data For
Monday, 7/20/2026
NAM Raw Data For
Tuesday, 7/21/2026

Technical Model Notes

The North American Mesoscale Forecast System (NAM) is a regional numerical weather prediction model operated by NOAA's National Centers for Environmental Prediction (NCEP). Running on a 12-kilometer horizontal grid with 60 vertical levels extending from the surface to 10 millibars, the NAM provides detailed forecasts for the continental United States, adjacent Pacific and Atlantic waters, and portions of Canada and Mexico.

NAM utilizes the Nonhydrostatic Mesoscale Model (NMM) dynamic core with advanced physics packages including the Kain-Fritsch convective parameterization scheme, Ferrier grid-scale microphysics, and the Mellor-Yamada-Janjić boundary layer scheme.