As excitement builds for the 138th Annual Kentucky Derby, so will the heat into the weekend. However, thunderstorms may be on the prowl prior to and during race day.
As many of the best three-year-old thoroughbreds in the nation make the run for the roses Saturday at Churchill Downs, the weather is drawing up plans of its own.
Provided thunderstorms hold off around Louisville Saturday, it has the potential to be the hottest derby day since May 2, 1959, when temperatures hit 94 degrees.
That day was the hottest Kentucky Derby on record according to the National Weather Service in Louisville.
Throughout this week a west to east zone of showers and thunderstorms has stretched across the Plains, Midwest and part of the East.
While heat will build through the end of the week, it may end with crashing thunderstorms this weekend. Right now it is too close to call when the storms will make their move.
Disturbances moving eastward over the Midwest have caused this zone of rainfall to shift north and south over the Ohio Valley with locally severe thunderstorms.
The pattern is likely to continue into the weekend.
During the next several of days the trend will be for this particular highway of storms to stay north of Louisville, putting the region in a zone of building heat and humidity. Temperatures will climb well into the 80s and lower 90s over the Ohio Valley.
However, we continue to have concerns about the zone of storms dipping back to the south over the weekend.
Timing of this is critical and will be affected by local complexes of thunderstorms that have not formed yet.
If one of these were to form to the northwest during Saturday, it could crash through at the wrong time (during or prior to the race) with torrential downpours and potentially dangerous weather conditions with frequent lightning strikes, large hail and strong winds.
The storms could rapidly knock the temperature down by 20 degrees or more.
Meanwhile, a swath of tropical downpours will drift northward from the Gulf of Mexico and could bring scattered storms to the vicinity sometime from late Thursday into Friday morning.
The track at Churchill Downs drains well, but there is the potential for one of these storms Thursday into Saturday to make for sloppy conditions.
A couple of storms focused on Indianapolis during Tuesday, delivering an inch and a half of rain.
This story was published on Wednesday, May 2, 2012. The story "Derby Day Downpours Possible at Churchill Downs" has the latest.
Rain and thunderstorms spreading to the East on Tuesday will put the brakes on the warmup following Easter weekend.
While remaining on a localized level through Tuesday, severe weather will ramp up across the Plains on Wednesday.
Although spring may be in full swing, more than one-third of the Great Lakes remains covered in ice.
A potent area of low pressure moving into the West will dictate the weather from Washington to Texas heading into the new week.
After taking a tumble Easter Sunday, temperatures will quickly rebound in Boston for Patriots' Day.
There hasn't been any measurable precipitation in San Francisco since April 4.
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