Sweltering heat? Rain? What does the forecast have in store for 150th Kentucky Derby

The 150th running of the Kentucky Derby is fast approaching, and as of Monday afternoon, forecasters can’t rule out rain for weekend celebrations in Louisville and Lexington.

That’s why forecasters like National Weather Service meteorologist Brian Neudorff are encouraging Derby revelers to keep a close eye on the forecast this week.

“If you’re planning on coming to the Derby, keep it constant, be vigilant,” Neudorff told the Herald-Leader in a phone interview Monday.

Here’s a look at what the forecast has in store for this weekend, but know conditions are likely to change. Neudorff said by Wednesday, forecasters should have a clearer picture of what the weather will look like for this weekend’s races.

“Right now, we’re looking at the forecast through a telescope,” Neudorff, who works for the NWS Louisville office, said of predictions Monday.

What does the forecast look like for Lexington this weekend?

Forecasts from the NWS in Louisville and The Weather Channel are calling for possible showers and thunderstorms to move into the area Friday. As of Tuesday morning, the chance of rain Friday is 60%, with diminishing chances moving into Saturday, according to the National Weather Service forecast. By comparison, The Weather Channel puts the chance at roughly 40%.

For Saturday, the National Weather Service predicts a 50% chance of showers and thunderstorms, while The Weather Channel puts that probability at roughly 60%, as of Tuesday morning.

In a forecast Monday, meteorologist Chris Bailey noted temperatures could reach into the 90s Thursday.

“That’s ahead of a cold front pushing in with showers and thunderstorms Thursday night into Kentucky Oaks Day Friday. Some lingering stuff may hold on into the start of Kentucky Derby Saturday, especially in the east,” Bailey wrote.

That said, some forecasting models anticipate favorable weather for the race itself, with the front clearing well before post time, Bailey added.

As for temperatures in Lexington Friday and Saturday, the NWS is calling for temperature highs close to 80 degrees Fahrenheit, with lows around 60.

What does the forecast look like for Louisville this weekend?

For Louisville Friday, the NWS projects a 70% of precipitation, with a possible thunderstorm in the afternoon, the agency’s seven-day forecast said Tuesday morning.

Still, on Derby Day, the chance of rain was much lower at about 40% with mostly sunny conditions and a temperature high close to 80 degrees. The temperature Saturday could drop as low as 61 degrees, the NWS said.

By comparison, The Weather Channel’s 10-day forecast for Louisville called for rain Friday morning, with scattered thunderstorms and showers possible early in the day. It put the chance for rain at 50%, as of Tuesday morning. Saturday, The Weather Channel predicts a temperature high of about 80 degrees with scattered thunderstorms possible. It sets the chance of rain at 60%.

What the Kentucky Derby’s historical weather tells us

The NWS in Louisville also keeps a record of weather conditions for the Kentucky Derby at Churchill Downs going back to 1875, and it may offer another clue for what to expect Saturday.

For the last four years, the agency recorded a mix of cloudy and sunny conditions, but no precipitation in the afternoon or early evening. In 2019, it recorded only 0.34 inches. Overall, since 2014, Kentucky Derbies have tended to be drier.

Here’s a look at some weather records for the Kentucky Derby set over its nearly 150-year run:

• Coldest temperature: 36 degrees on May 4, 1940, and May 4, 1957. (The temperatures for the 1957 running were accompanied by frigid northern winds blowing between 20 to 25 mph.)

• Hottest temperature: 94 degrees on May 2, 1959.

• Wettest Derby on record: 3.15 inches of rain on May 5, 2018.

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