Author Archives: wx

Severe weather close, but not likely here

Fri. June 20, 2019  5 P.M.

A strong line of strong to severe thunderstorms has moved into southwestern IN and western KY during the past hour.  Numerous reports of damaging winds have come from MO/IL.  What’s left of the squall line should pass through Jefferson County between 8 and 9 P.M.  The storms will be much weaker by that time because it’ll be moving into an area of significantly lower moisture.  The air over the western third of KY and extreme SW IN is very humid and primed for severe winds over the next few hours AND extremely heavy rains after midnight.  Meanwhile, the really rich moisture will not reach us so storm strength and rain totals will not be excessive.

Some of the lighter rain from this system could linger into the mid-morning hours tomorrow, however.

Derby Day update

3:15 P.M.

Radar indications are now projecting the heaviest period of rain at Churchill Downs should be between 3:45 and 6 P.M.  Rain should lighten, perhaps even end, by Race Time.  Either way, it looks like the track condition will be either sloppy or muddy.

Horse race reminder:

No one ever bets enough on a winning horse.

Derby Weather

Sat. May 4, 2019

Another rainy one!

Although it won’t be as bad as last year, we’ll still have our second wet Derby in a row.  After giving us a little hope yesterday, the models have settled back into a slower developing southern system.  That keeps us wet most of the afternoon into the evening.

Here’s how it shapes up:  cloudy this morning followed by periods of light rain most of the afternoon.  Then, the worst part of the forecast.  Expect a period of heavier rain (perhaps even some thunder/lightning) between roughly 5 to 7 P.M.  After the Derby, rain tapers off during the evening.  Temperatures remain in the 60’s all day.

In spite of the weather, I hope you have a Derby winner!

Glimmer of hope fading

Friday, May 3, 2019

Models backing off from earlier trends.

After giving a promise of rain fading away by early afternoon with models runs from earlier today, tonight”s NAM family has taken most of the hope away.

Forecast now holds rain (mostly light) in Louisville throughout most of the afternoon.  Earliest end to rain now looks like 5 P.M. with a 40% chance it’ll still be raining lightly by Derby time.  Two years in a row!

Derby forecast looking better!

Friday, May 3, 2019

Latest data shows heavy rains heading south of us

After several days of increasingly gloomy forecasts for Derby Day weather, this morning’s product suite shows a definite trend toward better weather for tomorrow.

Models are now shifting the storm path to a more southerly route.  That means less rain locally and a quicker departure during the early afternoon.  Good news on both fronts.

Assuming this model shift is real, here’s my latest Derby Day forecast:  Light rain during the morning fading away to out southeast by early afternoon.  Some sunshine could show up by late afternoon.  Temperatures will be in the low 60’s during the rain but warm into the low 70’s by late afternoon.  Derby time:  mostly cloudy with a temperature near 72.  Track should be “good.”

Of course, remembering what happened last Derby Day, the above may not be the “last word”.   But the most recent trends are looking much better.

Now, the horses!?   Next question, please.

As a rule                                                                                                                                                             Horses are cruel                                                                                                                                              You bet their number                                                                                                                                       They barely lumber.

Earth Day 2019

Thoughts on Earth Day 50 

Tuesday, April 23, 2019

Earth Day should be a day of joyful ceremony and celebration.  But, instead, it’s more of a horror show – full of predictions of death, misery, etc.  In general it’s a day of dire warnings of horrible doom and gloom in our near future.  And, of course, the fault is all ours.

So, why should Earth Day be a time of celebration?  Let’s take a quick look at what’s been going on for the past century, or so.                                                                                                                             1). Earth’s population in 1900 was an estimated 1.6 billion.  Poverty  rates and malnutrition rates were very high.  Disease was rampant.  Today Earth’s population is estimated at 7.8 billion.  Poverty rates and malnutrition rates are the lowest ever.  Many common diseases of the past have been eliminated.  (Or at least they were eliminated until some of today’s enlightened population decided that it might be fun to bring them back.  But, at least they’ve offered their own children as test subjects.  I digress.)

2).  Food was a scarce commodity in the first half of the 20th Century.  Now, thanks to a warming Earth, modern technology and higher carbon dioxide levels, food is abundant.  (So abundant in fact that in the U.S.  much of our corn production is not even eaten.  Rather, it goes to making ethanol which is then mixed with gasoline to make our cars run less efficiently.  In addition, the production/distribution of ethanol produces MORE carbon dioxide than it saves as a fuel!  Only in America!  I digress.)  Today, estimated global food production creates an equivalent of roughly 2800 calories per person per day.  Past Earth Day predictions foresaw mass starvation and global wars over food by now.  Unfortunately, food distribution is largely a political problem, so food is not shared equally.

3).  Earth Day sages have also missed on may other smaller scale predictions.  As it turns out Al Gore’s famous photo of a polar bear floating on a lonely, small iceberg was photoshopped.  Polar bears were not disappearing.  In fact their population is now higher than ever recorded.  Arctic Sea ice has not disappeared.  In fact, sea ice yearly minimums have actually be increasing over the past decade.  Global hurricane production/intensity has not increased in the past 3-4 decades.  (Yes, there’s been a lot more damage – because we keep building stuff on barrier islands.)  The frequency of winter storms has also shown no increase.

In fact, there have been articles floating around the internet recently “grading” 49 years of Earth Day predictions.  So far NOT ONE has come true!  And this year’s theme – species extinction – is sure to keep the Earth Day score unblemished.  Here it is:  30% to 50% of Earth’s species will be on the final road to extinction by 2050.  They’re calling it the 6th Great Extinction.  Interestingly, even if the prediction were to somehow prove to be correct, Earth would still have more species than BEFORE the last Great Extinction 65 million years ago.

So, what’s all the fuss about carbon dioxide?

There’s a very vocal sect with a religious-like  fervor that believes that increasing carbon dioxide is going to kill us all.  They don’t seem to realize that carbon dioxide is an extremely beneficial gas.  After all, life on  Earth is carbon based.  Many times in the past carbon dioxide levels have been much higher than now.  Most of the past 10,000 years Earth’s temperature has been higher than now.  We are still recovering from the Little Ice Age (started in the 16th century and ended about the mid 19th century).  The rate of global warming from the late 1970’s to about 2010 was just .1 deg. F more than a similar 30-year period at the start of the 20th Century.  So, it’s not so unusual.  Only then, nobody thought it was the beginning of the end of the world.

But, there is some concern about rising atmospheric carbon dioxide.  How much?  We just don’t know.  We’ve all heard/read estimates that a rise to about 550 parts per million would warm Earth by 3 to 8 degrees C  (5-14 deg F).  All those estimates come from computer modelling of the atmosphere.  Luckily, none of those models has ever shown much skill at its assigned task.  And, there are also additional problems with some assumptions the models make.

One thing we do know (at least we think we do) is if you only consider carbon dioxide and nothing else, Earth’s temperature should rise about 1 deg F.  for a carbon dioxide level of 550 ppm.  No big deal.

The problem, however, is that carbon dioxide doesn’t act alone.  It interacts with many things in the Earth/atmospheric system.  How much do all those interactions effect warming or cooling of the Earth.  The answer is:  We just don’t know!  Until we know definitively, we have no way to determine how much increasing carbon dioxide will change our world.  So far, the benefits from the increasing carbon dioxide far outweigh the negatives.

That’s why Earth Day should be a day of celebration rather a rant of doom and gloom.

Not so interesting after all

Sunday, April 14, 2019  2:45 P.M.

Cooler, drier air takes over

Thunderstorm chances have dropped to near nil as the atmosphere has rapidly drier this afternoon.  Still a chance for some showers over the next few hours as cooler air rushes in. Showers, if any, will be scattered with only about 30-40% areal coverage.

Winds, which did gust once to 40 mph at SDF have remained mostly in the mid to upper 30’s and will slowly diminish for the rest of the afternoon. Temperatures will also begin a rapid drop.

Stuff

Forrest Mars, the inventor of M & M’s, was allergic to peanuts.  Thus, he never got to taste his invention.

 

Interesting situation for a couple of hours

Sunday, April 14, 2019  12:30 P.M.

Thunderstorms possible

Sudden heating and increasing dew points for the past few hours have pushed us into an interesting weather pattern for the next 2-3 hours.  A rather diffuse low pressure system has been over us this morning (it brought us the overnight rain).  The low is now moving northeast into northern IN/MI.  That’s why we’ve seen the rapid increase in winds.  But, low level moisture is now dropping!  Also, in the wake of the low, a cold front is now marching from west to east across southern IN and KY.  The front should pass the I-65 corridor between 2 -3 P.M.

Ahead of the front scattered thunderstorms are popping up. Due to the decreasing moisture, no solid line of storms is expected.  But, some isolated storm or two could generate some gusty winds, perhaps (but not likely) even up to 50 mph.  Any thunderstorm threat locally will be over by 3 P.M.  Stronger storms, even a severe storm or two, could pop up over eastern KY later this afternoon.

About those winds…

1).  We are under a Wind Advisory this afternoon.

2).  National Weather Service Definition of a Wind Advisory is sustained winds of 31-39 mph for at least an hour and/or wind gusts of 46 mph to 57 mph.

3).  The current NWS forecast predicts wind gusts up to 40 mph.

4).  The current Hazardous Weather Advisory and Weather Advisory say gusts to 45 mph.

5).  Go figure!  Why issue an Advisory for something they aren’t forecasting?

6).  And, the prediction isn’t even going to happen.  The strongest wind fields are over eastern KY (east of I-75).  Locally, our wind gusts should top out in the mid 30’s.

Stuff

Q is the only letter of the alphabet that does not appear in any state name.

 

Astronomical Spring arrives at 5:58 this evening

Wed., March 20, 2019

Is the Equinox equal?

The Spring (or vernal) Equinox arrives this evening as the sun will be directly above the Equator at 5:58 EDT.  And, even though the word equinox roughly translates into “equal night”, that’s not exactly true.  The common interpretation for the day of the equinox is 12 hours of day and 12 hours of night.   But if you look at the sunrise/sunset table, you’ll see today has 12 hours 8 minutes between sunrise and sunset.  So, day and night are not 12-12 as most people think.

What accounts for the extra 8 minutes?  Our atmosphere! On its roughly 93 million mile journey to Earth, sunlight travels through a vacuum.  For the last 10-20 miles, however, the sunlight encounters a higher density medium (the atmosphere).  The closer it comes to the surface, the higher the density.  When light travels into a region of higher density, it bends.  This bending is properly called refraction.  Or, in the case of the sunlight and Earth, atmospheric refraction.

Courtesy: timeanddate.com

So, when we see the sun sitting on the horizon, it is actually below the horizon.  But, we still “see” the sun because the atmosphere refracts (bends) the sunlight back to our eyes.  From the time we perceive the sun on the horizon until it drops out of our vision, four minutes go by.

So, if the Earth had no atmosphere (we’d be in BIG trouble), sun rise and set would be exactly 12 hours apart.  Because we do have an atmosphere, you must add the extra 4 minutes at sunrise and four more at sunset. Thus, the day of the Equinox has 12 hours 8 minutes between sunrise and sunset

Full moon tonight

The March full moon is most commonly called the Worm Moon (think robins in the early spring).  It has many lessor known names as well…Lenten Moon,  Crow Moon, Crust Moon, Chaste Moon, Sugar Moon and Sap Moon.

Our moon will be “full” at 9:42 P.M.  Moon rise tonight at 7:38 PM EDT.

Wait, one more thing…

Just trying to wrap things up in a neat little package…

Q.  Why does the moon look much larger near the horizon than it does higher in the sky?

Ans:  atmospheric refraction (plus something called the apparent shape of the sky)                         Note:  The moon on the horizon problem is still considered as the Moon Illusion.  People have been trying to explain it for over 2000 years.  Ptolemy was one the first to try.  His suggestion was very similar to the one I gave above.  But, it’s still under debate.

A new twist

Update  5:25 P.M.

The line of storms did strengthen, but not much.  Line should push across Jefferson County without any significant problems.  East of Jefferson County, the line should be stronger, with possibly a severe storm warning or two this evening.

On the positive side, the squall line will actually decrease the strong wind fields  for an hour or two

 

 

Update  4:45 P.M.

Radar IS showing a definite uptick in strength of the approaching thunderstorms.  Between now and 6 P.M., expect a line of strong thunderstorms to move across the metro area.  Expect brief heavy downpours, additional strong gust winds and possibly some hail.

 

 

4:15 P.M. Thurs., March 14, 2019

Line of storms still crawling eastward

As of 4 P.M. the only strong-to-severe thunderstorm left is racing across northern Clark Co. IN.

Elsewhere, the remaining narrow line of storms still lies west of the Louisville area.  No severe activity has been noted in the part of the line headed our way.

The items above have worked about as expected since the weakening trend noticed a couple of hours ago.  However, we are not out of the woods yet.  One of the two short-term models predicts the line to re-intensify as it approaches I-65 and become strong again east of I-65 for a few hours this evening. That’s the HRRR model.  It’s partner, the RAP, does not.

As of this time, local radar does not show any rebuilding… yet.  If that continues and the RAP is correct, we should have minimal effects from the squall line. However, we’ll have to watch out for any intensification of the line as that would increase the potential for possible severe wind gusts – especially along and east of I-65.

WOW

I just noticed that the airport reported 61 mph wind gusts earlier this afternoon.  Bowman Field’s top gust reached 56 mph.  Ft Knox topped out at 53 mph.  Mostly likely, if we do get thunderstorms in the next hour or two, they won’t match those winds!