Category Archives: forecast

Stormy night

11:30 P.M. update…Feb. 28, 2017

As mentioned on previous post, the southern Illinois/southern Indiana region as become the new “hot spot” for severe/tornadic thunderstorms.   Super cell now crossing the Wabash River about 40 miles northwest of Evansville has a history of tornado production and should continue to create problems as it continues on a line about 40 miles north of the Ohio River.  This system is moving into a more stable atmosphere so activity will slowly weaken as it approaches the I-65 corridor.

In addition a large cluster of thunderstorms over southwestern KY/TN will also be weakening as it moves about 40-50 mph toward the northeast.  This should be in the Louisville area between about 2 A.M. until 4 A.M.  Biggest threat for us from these storms will be heavy rains/flash flooding.

Finally, the cold front will bring additional thunderstorms across the area between 7 A.M. and Noon.  Once again, flooding will be the primary threat.

Atmosphere is set for some big fireworks

Tuesday, Feb. 28, 2017  3:30 P.M.

Both surface and upper air components of the atmosphere are converging on a major “sweet spot” where (and when) ample supplies of severe storm ingredients will come together soon.  A major outbreak of severe weather is expected with large hail, strong winds and tornadoes all looking likely.

WHERE:  Texas, eastern Oklahoma, most of Arkansas, eastern Missouri, Illinois and western Indiana.  Perhaps far western KY as well.

WHEN:  The arrival of the strong storm ingredients should occur over the southern parts of the states listed above around 6 P.M. EST.  The most severe activity will continue for about 8-12 hours.  The prime conditions will uncouple after that and activity will diminish tomorrow morning.  Additional strong storms (but not as strong as tonight’s storms) may reform tomorrow afternoon over eastern KY.

A storm system developing over central Missouri now will rapidly intensify under a very strong upper air flow over the Mississippi Valley and reach the Great Lakes by morning.  Trailing the low pressure will be an eastward moving cold front.  As the front moves into the warm, moist air thunderstorms will break out this evening and accelerate northeastward.  The strong wind fields aloft will have no problems converting the thunderstorms into severe weather-makers quickly.  During the evening, the biggest problems will be over ne TX, east OK and AR.  By Midnight, the greatest threat pushes northward into eastern MO, IL and western IN.  From Midnight until about 6 A.M., the models put a  “bulls eye” over southern IL and southern IN for the greatest damage risk.  NOTE: although the models zero in on the area north of the Ohio River, a few isolated severe storms could develop over western KY counties bordering the Ohio River.

By 6 A.M. the severe storms should be over, or at least diminishing.  By that time the remaining lines/clusters of thunderstorms will be approaching the Louisville area.  The primary area of rain/storms should push through the I-65 corridor between 8 A.M. and Noon.  Some strong winds may still be possible, but the primary threat for our area will be flash flooding.  After the periods of heavy rain today, the ground is saturated.  Additional heavy downpours tomorrow morning would be enough to trigger brief flash flooding.

The cold front is expected to pass though the Louisville area about Noon tomorrow so any additional severe weather generation tomorrow afternoon will be over eastern KY.  Meanwhile, we’ll start a drying process during the afternoon as cooler air arrives.

Stuff

Sunday night’s big Oscar blunder wasn’t the first time that has happened.  But, the first time it happened, the category wasn’t a major one.  In 1964, the “Best Music Score”  award was announced for the movie “Tom Jones.”  But that movie wasn’t even nominated!  The actual winner was Andre Previn for “Irma La Douce.”

Another severe weather attempt

Monday, Feb. 27, 2017

Another strong storm will come out of the southern Rockies and push toward the Great Lakes by Wednesday.  This is a classic severe storm set-up, but the likely timing of the system currently puts us into the very low side of severe storm possibilities.  The highest risk areas will be west of us tomorrow afternoon/evening and east of us for Wednesday afternoon.

The past two similar systems were moisture-shy.  In both cases, nothing of consequence happened locally – thanks to that lack of moisture.  This time, however, there will be plenty of moisture in the equation.  So severe storm outbreaks appear likely tomorrow and Wednesday, but, as mentioned above, the main part of the storm system will reach us during the lull between the two outbreaks.

Here’s how it’s shaping up…a warm front will push through the lower Ohio Valley tonight and tomorrow morning.  This will bring high moisture content into the area.  The front should generate a few hours of showers (and possible thunderstorms) tomorrow morning between about 7 A.M. through Noon.  Any thunderstorms that form tomorrow morning could produce small hail. Then, we’ll see a windy and warm afternoon with temperatures nearing 70 degrees.

During tomorrow afternoon/evening thunderstorms will develop along a cold front from Arkansas to Missouri into Illinois.  A widespread outbreak of severe weather is expected.  As the night continues this cluster of severe weather will drift eastward and weaken.  It is expected to drift through the I-65 corridor Wednesday morning remaining in the weakened state.  Then, Wednesday afternoon it is expected to re-intensify into another area of strong to severe storms as it moves east of the I-75 corridor.

Even though the severe threat looks quite low for the Louisville area, the two (or more) rain systems we expect could easily drop !” to 1.5″ of rain by midday Wednesday.

Stuff

Each panel of glass on the Grand Canyon Skywalk can safely hold 800 people even though the glass is only 2.5″ thick.

Severe weather threat is diminishing

Fri, Feb 24, 2017  5:30 P.M.

Moisture is still iimited and models continue to pay far more attention to northeast IN and MI.  Cold front should pass through Jefferson County between 8:30 and 9:30 P.M.  Some strong gusty winds are likely with the front, but winds should NOT reach the 58 mph range (needed to be called “Severe”).

Severe Storms Possible Tonight

Friday, Feb.24, 2017 Noon

A strong storm forming between St. Louis and Chicago will intensify rapidly during the day as it moves quickly northeast into Michigan.  North and west of the storm track heavy snow is likely.  However, the “warm sector” south and east of the storm will remain dry most of the day as we wait for a supply of moisture to arrive from the south.  Once the moisture gets north,  the strong dynamics of the parent storm should have no problem producing some severe thunderstorms.  Primary threat will be strong winds.  Hail is a slight risk while tornado chance is pretty close to zero.

This system is similar to the last time severe weather was widely advertised, but failed to show up.  The problem is with the moisture.  The dynamics with the system are tremendous, but the thermodynamics are quite weak.  So, once again, the various models are relatively low on the “probability” of storm formation, but the so-called “conditional probability” for severe storms is high.  What that means in normal people-speak is that the overall chance for a thunderstorm hitting you is small (about 30%).  But IF a thunderstorm forms, there is a high chance it’ll reach severe levels (about 50%).    So, if you multiply the two numbers you get a roughly 15% chance for severe winds within 25 miles of your home tonight. Obviously, the chance at any single point (your home)  is much lower.

The models agree well on timing.  The arrival of the cold front trailing the surface storm and sufficient moisture to generate thunderstorms should be about the same time.  Best timing for Louisville looks like between 8 and 10 P.M.  While some storms should form west of Louisville earlier, this system shouldn’t get well organized until it gets east of I-65.  Areas east of Louisville have a greater chance for wind damage than we do.  Best chance looks like 9 P.M. until Midnight for areas east of I-65.

Caution

As always, you’ll be hearing a lot of hype about storm potential this afternoon/evening.  What you’ll be hearing will be “the worst case scenario.”  Luckily, nature rarely reaches our hyped up expectations.

Interrupted sleep?

Monday. Feb. 6, 2017

Yes, it appears that thunder and lightning will be visiting our area during the late night hours tonight.  Also, the Severe Storms Center has us in a “slight” risk area for severe thunderstorms tomorrow.  However no severe storms are expected with tonight’s rain/thunder/lightning.

The situation looks like this:  a weak upper air disturbance will float slowly over the Ohio Valley between (roughly) Midnight and Noon tomorrow.  This system is starting to pick up some  Gulf moisture and rain/thunderstorms are popping up over northern TX, AR, west TN and southern KY.  Rain should become widespread over our area after Midnight and finally end around midday.  Thunderstorms will be embedded in the rain shield with the best chance for thunder here about 5 A.M. to 10 A.M.  Overnight instability will be low and the upper air dynamics, while good for an April/May severe weather situation, are actually pretty low for a winter system.  As a result, I don’t expect any severe storms overnight or tomorrow morning.  The dynamics aloft will have a hard time overcoming the lower level thermodynamics.

Then, atmospheric conditions change tomorrow afternoon/evening.  The morning system will drag most of the deep layer of moisture northeast of us.  But, a cold front will be approaching from the northwest.  The dynamics with this coupled surface/upper air system are expected to be much stronger than the overnight system.  However, most of the moisture will have disappeared.  So, the chances for thunderstorms to form along this front are quite small – about 10-20%.  But, if thunderstorms do manage to form, strong gusty winds and hail will be likely.  So, severe storms are possible late tomorrow afternoon , but the chances we’ll have any in the area are less than 10%.  Not much to worry about.  (But a few flurries will be possible early Wednesday.)

February

A couple of weeks ago, a major change in the upper air pattern looked like a good possibility for North America for this month.  The models were leaning toward temperatures being below normal for much of this month.  That trend lasted several days, but since then has shifted back to the primary pattern it has shown much of the winter – cold and wet over the western states and warm and wet over the east.  It looks well locked in, so not much hope for snow lovers.  Bad winter in that regard.

Super Bowl

It was amazing to watch New England turn the tide and rally last night.  You’ve got to give Tom Brady and the Pats credit for putting themselves to win the game, but to my mind, they NEVER should have won the game.  Atlanta just outright “gave” the game away.  With time running out, Atlanta had a second down with the ball in easy field goal range AND an 8 point lead.  Keep the ball where it was.   Run down the clock with a couple of runs – kick the field goal – game over – Super Bowl winners!  But, wait!  Somebody (I assume it was the offensive coordinator) calls a pass play that requires a deep dropback  by the quarterback.  Play starts, qb drops back and gets sacked.  13 yards lost – no longer in field goal range – Patriots get the ball back with a chance to tie the game.  And, they did –  then made it look easy in overtime.

Whoever called that play must have thought he’d catch New England off guard.  Seattle thought the same thing two years ago.  Look where it got them.

Stuff

The popcorn you buy at a movie theater costs more per pound than a filet mignon.

Another small snow

Saturday, January 28, 2017  3:30 P.M.

In similar fashion to our previous snow this month, the GFS and NAM are breaking tomorrow’s snow chances into two distinct segments.  With the latest NAM data, the only significant difference between the two models is with timing.  The NAM is a little faster, a common difference between the two.

Here’s how it looks now:  light snow should begin around daybreak in Louisville (earlier south of the city).  This will fade away by late morning, leaving only small amounts for the Louisville area. Maybe half an inch here, but a generous inch is possible over southern KY.  By late afternoon, a strong upper air system will plunge over the region and produce another period of light snow.  The morning system will take most of the available moisture away as it moves east.  Daytime heating will melt most of the morning snow before the afternoon snow arrives.

When the second snow ends by early evening, there probably won’t be much to show for the day’s efforts.  About .5″ locally, but 1″-3″ possible along and east of I-75.

Note:

Yesterday’s average temperature was exactly “normal” and today we’re back to above normal temperatures.  In fact, we haven’t had a below normal day here in almost three weeks.  January 9th was the most recent colder-than-normal day here.

Stuff

“young Americans” won the Academy Award for Best Documentary of 1968 during the 1969 awards ceremony in 1969.  Later it was discovered had been show in a theater in October 1967, making it ineligible for the 1968 award.  The Oscar was revoked, the only time that has happened in Oscar history.

 

Friday flurries!

Friday, January 27, 2017  4 P.M.

A weak upper air disturbance this morning brought us some flurries and a second one will bring us some more flurries for the evening rush hour.  With temperatures safely above the 32-degree mark, no problems are expected.

Cold weather should remain through the weekend with additional weak disturbances bringing additional periods of flurries.  Finally, a much stronger upper air system will cross the area Sunday afternoon and evening.  This is expected to upgrade the flurries to  a period of light snow and/or snow showers.  This morning the GFS and NAM were far apart on their portrayals of what the result will look like, but now the NAM upping its game toward the GFS solution.  But, don’t get too excited – even the “stronger” GFS still keeps snow expectations below one inch.

The current outlook for Sunday calls for some light snow/snow showers between (roughly) 3 P.M. and 8 P.M.  This should not have much of an effect on surface roadways, but bridges/overpasses/etc. could get some slick spots.  Snow accumulation should be light – anywhere from a dusting up to an inch.  For Louisville, about a half inch seems likely.

Bummer

My post earlier this week has already proven me right and wrong.  My long time conviction that long range prediction is  a fool’s game has been proven yet again.  But, my insistence to try it anyway is where I went wrong (probably).  My idea that the cold air arriving this weekend would hold through next week will not happen – unseasonably mild weather will return for next week.  Further, I said that some really cold weather should arrive around Super Bowl time – that part will probably hold, although it’s not looking quite as cold.  The worst part of my “outlook” was that the below normal trend should continue through most of February.  Sadly, that appears to no longer the case.

Moral of the story:  I should follow my own advice!

Still hope for some “winter” weather

Sunday, January 22, 2017

It’s been well advertised for the past  ten days or so – an upper level pattern change that was due to begin late this week.  That would shift the major storm activity from the Pacific coast into the eastern U.S., setting up the winter-weather favoring “East Coast trough – West Coast ridge” pattern that would open eastern North America to renewed outbreaks of arctic air.  We haven’t seen this pattern much this winter.  It set up for about 2-3 weeks during December and then again briefly in early January.  Each time, it could not establish a foothold and returned blasting the western U.S. with heavy rain and snow.  That has been good for California, as the years-long drought has been wiped out (for now).

As usually happens when forecasters try to look out a week or two in advance,  the expectations don’t meet the reality when it finally arrives.  That seems to be happening this time as well.  Colder weather appears likely by late week and the weekend.  But, current forecasts for temperatures are running 5-10 degrees warmer than they were a few days ago.  So, it looks as though the first attempt to establish the east coast trough will only drop us into the “near normal” range rather than the previous “below normal” expectations.

But, snow lovers,  there is some good news.  The GFS and the European model continue to deepen (strengthen) the troughing over the eastern U.S. so that Super Bowl weekend should see the beginning of some strong cold air outbreaks ( and maybe some snow(s)).

Although I have repeatedly stated that long range forecasts can be highly unreliable, I will take a stab at what happens after that.  The U.S. has a forecast model known as the Climate Forecast System (CFS) designed to project the months ahead in general terms.  Since I usually concern myself with current weather and a few days ahead,  I’ve never paid much attention to the CFS.   But, if you want to dream big, the CFS is predicting that once the east coast trough really establishes itself (11-14 days from now), it will hold until the end of February!  That could make for a lot of fun next month

(And that could be our last chance as the CFS expects March to return to above normal temperatures.)

Current weather

I seems pretty obvious by now that those forecasts for heavy rains (Thunderstorms?) and possible flooding (especially south of Louisville) are not going to materialize tonight and tomorrow. We’ll probably see some rain tonight, mostly after midnight.  Total should be a quarter-inch or less.  After that, the next few days should be dry with continued mild temperatures.

Stuff

If you were asked,” How many Presidents has Kentucky produced?”, the obvious answer would be “one.”  But, some people count Jefferson Davis as a second President.  That’s a “trick answer” as he was President of the CSA not the USA.  But, in a little-known historical quirk, Abraham Lincoln was actually the second Kentuckian to serve as President of the USA.  Here’s the story from the very interesting website, www.mentalfloss.com. …

In 1849, Zachary Taylor refused to be sworn in on a Sunday, because he was very strict about “keeping holy the Sabbath.” The position of president couldn’t just be vacant until Monday, so the President Pro Tempore of the Senate, David Rice Atchison, was brought in as a pinch hitter. There’s some debate as to whether this actually makes him the 12th president and Zachary Taylor the 13th, but obviously, it’s generally accepted that he doesn’t count. He didn’t even stake claim to the title, and repeatedly told people that he slept through most of his day as president. He must have had a good sense of humor about the whole thing, though, as evidenced by the inscription on his gravestone.

 

 

 

Snow update 2

10 P.M. Wed. Jan 4, 2017

Couple of updates…

1).  Models continue to run faster.  Snow should begin 7-9 A.M.  and taper off by early afternoon.  A SECOND period of snow should occur during evening rush hour.  Morning snow should amount to roughly one inch.  Second snow may reach .5″

2).  Most recent model runs have become “drier”, probably because of faster movement and the distinct two-phase nature of the snow system(s).

3). Road conditions described on earlier post still look good.

4).  Still looks like the heaviest snowfalls (combined from two snow periods)   will be east and south of Louisville.  Areas east of I-75 could reach 4″-5″.