non-Derby Weekend odds and ends

Sunday, May 3, 2020  5 P.M.


Weekend forecasts for Louisville were reasonably good although temperatures were several degrees higher than predicted yesterday. If this had been a “business as usual” Derby Day, I wonder how many bad sunburns the infield crowd would have suffered.  Today’s temperature forecast was far worse than yesterday’s.  The expected showers finally arrived, but rain so far has hardly been worth the effort.  We’ll still maintain a chance for a few more light showers until about 8-9 P.M.

Looks like a nice day tomorrow with mid 70’s highs, then a good shot at a more significant rainfall tomorrow night into Tuesday.

Below normal temperatures will prevail from midweek through the weekend.

Forecast Models

Homo Sapiens (that’s us) evolved, we believe between 200,000 and 300,000 years ago, but did not  develop language skills until about 50,000 years so.  So, we’ve been trying to predict the future for at least 50 thousand years.  The first scientific numerical attempts, that I’m aware of,  were by Lewis Richardson in the early 1920’s.  He used equations developed by Wilhelm Bjerknes ( the Farther of modern meteorology) to create a numerical “model” of the atmosphere.  He then extrapolated the input data forward in time.  He produced a 6-hour forecast for two cities in Europe.  Sounds pretty simple, but there are an enormous number of calculations required to move forecast data horizontally and vertically through the atmosphere, even for just six hours.  Working off and on, Richardson took six MONTHS to complete his 6-hour forecast!

The numerical prediction did not produce realistic results.  But, the concept was proven correct. But the huge number of calculations needed proved it was not feasible at the time.

Jump ahead two decades.  During World War II the military wanted some way to speed calculations needed during battles.  Started in 1943 the project ended in 1946 by calculating (very rapidly) trajectories for canon balls by a machine called eniac  (electrical numerical integrator and computer).

Story continues tomorrow



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