Archive for the ‘Tropical Weather Alert’ Tag

Tropical Storm Hermine – Tallahassee Alert –

 

THIS IS A VERY “TIME-SENSITIVE” REPORT

After viewing the graphic below my concerns for the residents of Tallahassee have increased; of course it goes without saying that my concerns are for everyone who might have to deal with this storm – no matter where they might be located.  Mainly, there are three factors involved in my concern for the 7th most highly populated city in Florida and its capital city.  One is that there is a strong chance that Hermine will become a hurricane before reaching the Florida coast.

Another:  The minimum distance from Gulf of Mexico waters to Tallahassee is about 25 miles.  One might consider 25 miles to be an adequate “buffer” to provide friction and thus slow down the winds approaching the city.  I think that assumption would be a mistake.  Furthermore, when surface or near-surface winds leave the water for land the slight slowing that might occur would tend to cause more air to rise.  A similar rising is what causes lake effect snows in certain Great Lakes coastal or near-coastal downwind locations.  In the case of humid winds from Hermine possibly decelerating due to friction over the land when approaching Tallahassee, the net effect could very well be more vertical cloud development (due to a greater amount of rising air) than would have occurred otherwise.  This phenomenon can intensify thunderstorms, the gusts that spill out from them, and the chaos that can generate tornadoes.  The increase in rainfall amounts can be dramatic.  So – be careful what you wish for.  Flooding is typically a bigger issue than the wind velocities in these cases.

Here is the third cause for my concern:  The graphic below from the National Weather Service showing the “cone of uncertainty” (8 PM EST, 8-31-2016) causes me to consider that Tallahassee might very well be under the right-hand leading quadrant of the storm when it makes landfall.  The right-hand leading quadrants of tropical cyclonic systems are usually the quadrants with the highest wind velocities, greatest probability for tornadoes, heaviest rains, and in coastal areas the greatest storm surge height.  The fact that currently the whole storm is beginning to move faster can increase the danger of the right-hand leading quadrant.

I urge residents of the Tallahassee area to be alert during the approach, passage, and departure of what is now Tropical Storm Hermine.  Do not take it lightly just because it is on the low side of the tropical storm wind velocity range at this time (evening of 8-31-2016).  

CLICK ON THE IMAGE BELOW TO ENLARGE. 

2016-8-31 8pm EST

CLICK ON THE IMAGE ABOVE TO ENLARGE. 

Update On Tropical Depression Nine (AL09) 8-29-2016, 10:30 pm EST

Compare this to the previous posting which was 24 hours earlier and you will see some change in the tracking model forecasts – which is to be expected.

I have greatest confidence in the TVCA run which is a consensus of 5 other models which have been good performers over the last few years.  Generally, the TVCA model is very close to the National Hurricane Center’s “official” track that is the basis for the “uncertainty” cones released to the public.  If you are one to pay attention to which models get mentioned or shown in weather reports you have surely heard of the “European model” which is labeled ECMWF.  You won’t find it on these spaghetti illustrations; Data from this model is restricted from being redistributed according to international agreement.   However, the National Weather Service official track runs very close to being the same as the ECMWF.  The BAMM and related models are still useful for long term runs but in this case I think you can pretty much ignore them (the ones that run off toward the west). 

Suppose you lived along the Nature Coast of Florida, (e.g. Citrus County) then you might feel that you have nothing to be concerned about because the tracks seem to be shifting northward.  But please remember, these tracks are merely forecasting the storm’s center.  In most cases the strongest winds are at the right hand, leading quadrant of such storms, which, in this case might cause Citrus County some concerns. 

Please be sure to click on the graphic for enlargement.

 

2016-8-30 L 0000z

Invest 99L Has Become Tropical Depression AL09

REMINDER:  THIS IS A TIME-SENSITIVE REPORT

As of late this afternoon, 8-29-2016, Invest 99L has strengthened to a tropical depression.  For up-to-date information on the system, I recommend Dr. Jeff Masters’ weblog (blog).  See link below:

https://www.wunderground.com/

Go to the top of the page and click on News & Blogs.

As of the time of this writing, Dr. Masters expresses reasonable confidence that the system will track in such a way that a landfall will occur somewhere in the Florida coast north of Tampa.  I urge all interested persons to pay close attention to Dr. Masters’ postings, the Weather Channel tropical reports, and your local news.

Here is the most recent version from my favorite spaghetti chart source, the National Center for Atmospheric Research in Boulder, Colorado (CLICK ON IMAGE TO ENLARGE):

2016-8-29 Model tracks

 

Sandy Alert – There Is No Shame In Evacuating!

What concerns me most is the number of people who will not address and act upon hurricane Sandy’s threat maturely. As a man who grew up in an environment where “being a man” meant being able to handle, support, protect, and defend – I can identify with the need to have it “together” in these types of situations. It was hard for me on the morning of 8-23-1992 to “order” my wife, two children, father-in-law, and mother-in-law into my van so that we could evacuate our two homes (separated by less than a mile) in Homestead, Florida to escape approaching hurricane Andrew. But, when we returned 3 days later we were thanking the Great Guy In the Sky that we were not there when the storm hit. It would have been a most traumatic experience and could have been deadly. Our house was a total loss and my in-laws’ house was severely damaged but not beyond repair. There are people today of all ages still suffering post traumatic stress syndrome over that hurricane of 20 years ago. Admittedly, the aftermath and rebuilding processes were extraordinarily difficult but we were together and healthy and I had very good insurance and did not lose my job. Thousands of people lost both their dwellings and their jobs! We had much for which to be grateful.

But, sometimes, in an attempt to handle, support, protect, and defend – people (men in particular, I think) tend to make macho decisions that they later regret – if they live to experience regret. One example is: Failing to evacuate dangerous areas that are subject to flooding, landslides, storm surges, etc. Believe me – there is no disgrace in fleeing in such circumstance. Sure, one wants to stay and protect his/her home and the “things” within it but such a mindset can backfire resulting in fatal consequences. Take my word for it, “things” can be replaced in time but once you lose your life of worse, that of a loved one – there is no going back or rebirth back into this dimension.

 Hurricane Sandy is a storm that has it all. Oh sure, it’s not a category 5 storm as was Andrew but it is a huge storm taking up an area more than the size of Texas one and one-half times! And – it has a strong pressure gradient. It has a very long fetch (distance of water over which the wind blows) which increases significantly the potential height of the storm surge.

 Just because the winds are within the category 1 range, remember that slight increases can cause exponential increases in the potential force. In fact, doubling the wind velocity quadruples the air’s potential force upon a surface that it strikes at right angles.  Early on in my teaching career it because quite apparent to me that most people assume that doubling the velocity simply doubles the force.  But that is far from true.  For example, an 80 mile per hour wind has FOUR TIMES the potential force of a 40 mile per hour wind. So DON’T think to yourself, “I know I can deal with a 40 mile per hour wind; in fact I and my dwelling can deal with one that is 80 miles per hour because that is just two times that of a “40.” YOU WOULD BE VERY, VERY WRONG! If you are interested in more on this subject, including an equation – go here:

https://cloudman23.wordpress.com/tag/wind-velocity-relative-to-force/

 A great deal of precipitation over land is expected with Sandy – so much that many of the drainage systems, both natural and man-made, will not be able to handle it. Trees will be less stable because of saturation of the soil and rock into which their roots are anchored. Combined with the wind force, many will come down. Unhealthy trees will snap. Mother Nature WILL do a great amount of pruning. Electricity will be cut off due to line damage from falling debris and flooding. Water pressure may drop or reduce to zero. Even modern gravity-feed systems require boosting due to the effects of friction and that usually requires electricity. If you have an electric pump with a well and no emergency generator, you could be out of luck. If your toilet is relatively modern you will still need about 1.6 gallons per flush. “If it’s yellow, let it mellow; if it’s brown, flush it down” might become your rule of thumb even if you have a lot of water stored (as in a tub that doesn’t slowly leak at the drain).

 Since much moisture will be drawn in by the storm from off the Atlantic and much cold air will be drawn down from the north, there is a very strong chance for SNOW with this storm.

 The bottom line, in my opinion is – If you are in the path of Sandy and:

  1. in a storm surge zone – evacuate.
  2. in a wooded area with big trees so close to your home that upon falling they are likely to do structural damage – evacuate.
  3. upon a hillside or mountainside where your area or an area above or below you has been stripped of most vegetation – evacuate.  Slides are a real danger in these cases.
  4. in a region that can easily flood  – evacuate.
  5. in a neighborhood where there is a lot of loose matter that could easily become damaging airborne projectiles – evacuate.
  6. in a mobile home or R.V. – evacuate.
  7. in a dwelling where, when you look out a front window you are looking down a street that is at right angles to your street – evacuate. The Venturi Effect can channel much higher winds and debris right into your dwelling!
  8. in any kind of a topographic restriction such as a narrow valley between two hills or mountains – evacuate for the same reason as in item 7.
  9. NOT prepared for many days without water service and/or electricity – evacuate.
  1. in an evacuation zone – evacuate!
  2. one who feels as though fleeing is a cowardly act – engage in a very quick but thorough attitude adjustment and ERR ON THE SIDE OF CAUTION.

BUT DON’T EVACUATE IF THE STORM IS UPON YOU UNLESS YOU FEEL THAT THE MOVE IS ACTUALLY SAFER THAN STAYING.

ISAAC SHOULD NOT BE IGNORED

This is the 4 pm EDT advisory for August 30, 2012.

Two left clicks on the image will enlarge it fully.

By the time you see this posting, the forecast graphic for what remains of Isaac (above) will probably be obsolete. Here is where to go to get a comparable update (however, the advisory above might be the last):

 http://www.nhc.noaa.gov/index.shtml

 In spite of modern technology the tasks of the National Hurricane Center’s forecasters are not easy and I guarantee they burned the midnight oil as this event unfolded. They have so many variables and unknowns to deal with.  I think they do a wonderful job.

Where I live, in west-central Florida about 18 miles inland from where the tiny Crystal River flows into the Gulf of Mexico, there are long-term concerns about our fresh water supply. So I had hoped that Isaac would provide just the right amount of water WITHOUT damaging and costly winds and flooding. Like most humans, I want all of the good but none of the bad that can come from Nature’s wonders.  At this time, Thursday evening, 8-30-2012, we are still getting some rain directly related to Isaac even though its center is about to move into Arkansas.  Hopefully the system will provide needed rain to drought stricken areas in it’s predicted path.  My retired-farmer uncle in Indiana indicates that it’s probably too late for the field corn but could be helpful to the soybeans.  As I write, flooding and potential flooding in certain areas of Louisiana are creating real headaches there.  There are some places claiming to have more water than with Katrina, albeit for different sets of circumstances.

There is so much information available today and I understand the great value of our acquired knowledge about tropical weather since I first began studying it formally (over 50 years ago) but sometimes, I confess, I think fondly of the days when we had little notion of what was going on until much later in a tropical cyclone’s life cycle. Now, it seems that the media devotes an inordinate amount of time telling us about the negatives and potential negatives that are going on all over the world and I can no longer bask in my ignorance as I used to because I haven’t the will-power or inclination to ignore the resources that are available. But, I concede, there are limits to the notion that ignorance is bliss.

I wish you peace, good health, and happiness.

Forecast for Irene by the European Model – posted 8-24-2011

This posting is time-sensitive and is now out of date.  For step by step instructions on access to an animated loop of the most current ECMWF (“European”) model go to the following link:  https://cloudman23.wordpress.com/2011/08/25/ecmwf-model-run-the-european-model/

Hurricane Irene is now a category 3 storm.

IF YOU ARE WITHIN THE PUBLISHED CONE OF UNCERTAINTY IT WOULD BE FOOLISH TO IGNORE THIS STORM EVEN THOUGH YOU MIGHT NOT BE CLOSE TO WHERE IT IS CURRENTLY PREDICTED TO GO.  That is not just my opinion but also the opinion of National Weather Service forecasters.

TO FIND THE MOST RECENT CONE OF UNCERTAINTY DEPICTION, GO TO THE RIGHT-HAND MARGIN OF THIS PAGE AND UNDER “TROPICAL WEATHER” CLICK ON “NATIONAL HURRICANE CENTER HOME.

The graphic that follows is a 72 hour (3 day) forecast position that originated at 0000 Greenwich Time on the 24th (which is 2000 hours on the 23rd EDT time – or 8 pm).   The path that this European Model predicts correspond closely with today’s official forecast track of the National Weather Service.

On this graphic, and most on this site, two independent left clicks will enlarge to the fullest.  The poorness of the resolution is due to considerable enlargement from the original.

2 LEFT CLICKS FOR FULL ENLARGEMENT

Early U.S. Landfall forecast for Irene by the European Model – 8-23-2011

 

 

 

 

This posting is time-sensitive and is now out of date.  For step by step instructions on access to an animated loop of the most current ECMWF (“European”) model go to the following link:  https://cloudman23.wordpress.com/2011/08/25/ecmwf-model-run-the-european-model/

 

 

Mind you, I am not formally trained in forecasting.  I am conveying to you what I am deriving from others and when I include my personal opinion I try to make that clear.  Also, very small changes in course can make a huge change in the location of a storm’s landfall, particularly when it is so far out as is Irene this moment.  For example, I am in West-Central Florida, 17 miles inland from the Gulf of Mexico but none-the-less, you can bet your sweet bippie that I’m on the alert.  SO IF YOU ARE WITHIN THE PUBLISHED CONE OF UNCERTAINTY IT WOULD BE FOOLISH TO IGNORE THIS STORM EVEN THOUGH YOU MIGHT NOT BE CLOSE TO WHERE IT IS CURRENTLY PREDICTED TO GO.  That is not just my opinion but also the opinion of National Weather Service forecasters.

TO FIND THE MOST RECENT CONE OF UNCERTAINTY DEPICTION, GO TO THE RIGHT-HAND MARGIN OF THIS PAGE AND UNDER “TROPICAL WEATHER” CLICK ON “NATIONAL HURRICANE CENTER HOME.

Over the last two years the European Model has done the best at predicting the paths of tropical systems under these particular circumstances.  The graphic that follows is a 5 day forecast position that originated at 0000 Greenwich Time on the 23rd (which is 2000 hours on the 22nd EDT time – or 8 pm).  A lot can happen in 5 days so take this for what it’s worth.  This does correspond closely with determinations made by the National Weather Service today.

I will check the next run (they occur at 0000 and 1200 or twice a day – Greenwich Time) and if there is a significant change I will post it.

On this graphic, and most on this site, two independent left clicks will enlarge to the fullest.

TROPICAL STORM HERMINE FORECAST, 9-9-2010

NOTE: the CDO to which the following report refers to is “Central Dense Overcast.”

THE FOLLOWING REPORT WAS TAKEN VERBATIM FROM THE NATIONAL HURRICANE CENTER’S WEBSITE.  IT WAS RELEASED AT 10 PM EASTERN DAYLIGHT TIME, 9-9-2010

000WTNT45 KNHC 070235TCDAT5TROPICAL STORM HERMINE DISCUSSION NUMBER 5NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL102010

1000 PM CDT MON SEP 06 2010

THE CENTER OF HERMINE MADE LANDFALL ON THE COAST OF NORTHEAST MEXICOAROUND 0130 UTC. PRIOR TO LANDFALL…SATELLITE DATA SHOWED THEFORMATION OF A CDO-LIKE FEATURE…WITH A LARGE AREA OF CONVECTIONALSO LOCATED NORTHEAST OF THE CENTER. THE LAST AIRCRAFT FIX AT 2333UTC SHOWED A PEAK 850-MB WIND OF 61 KT…WITH SFMR VALUES UP TO 56KT. DATA FROM THE BROWNSVILLE WSR-88D RADAR EARLIER INDICATED PEAKWINDS OF ABOUT 75 KT AT 4000 FT. THESE DATA SUGGEST THE LANDFALLINTENSITY WAS ABOUT 55 KT. SINCE LANDFALL…THE VELOCITIES FROM THEBROWNSVILLE RADAR HAVE DECREASED…AND THE INITIAL WIND SPEED ISLOWERED TO 50 KT. AS HERMINE WEAKENS…THE BIGGEST THREAT WILLSHIFT TO FLASH FLOODING FROM HEAVY RAINS AS THE CYCLONE MOVES INTO TEXAS.

THE INITIAL MOTION IS 330/12. THERE IS NO CHANGE TO THE FORECASTREASONING FROM THE PREVIOUS PACKAGE. HERMINE SHOULD MOVENORTH-NORTHWESTWARD AND THEN NORTHWARD AROUND THE WESTERN PERIPHERYOF A RIDGE OVER THE SOUTHEASTERN UNITED STATES FOR THE NEXT DAY ORSO. THEREAFTER…THE REMNANTS OF HERMINE WILL LIKELY TURN TOWARDTHE NORTHEAST AND EAST OVER THE CENTRAL UNITED STATES IN A COUPLEOF DAYS AS THE CYCLONE RIDES AROUND THE NORTHERN SIDE OF THATRIDGE. THE NHC FORECAST IS SHIFTED SLIGHTLY TO THE EAST IN GOODAGREEMENT WITH THE GFS AND ECMWF MODELS.


Atlantic Hurricane Season – Please Be Alert – 8-19-2010

We are entering the peak of the Atlantic hurricane season.  If you have not been influence by tropical activity thus far this year you might be under the impression that it’s an inactive season.  That would not be true.  Statistically, it has been about average to date. Though we cannot “plan the future” I feel strongly that we should plan “FOR” certain eventualities in the future.  I urge you to be prepared and alert in the event that a tropical system comes your way.

The following statement in “blue” was taken Verbatim Thursday morning (8-19-2010) from the Dr. Jeff Masters web-log found at http://www.wunderground.com/tropical/.

“The GFS, NOGAPS, and ECMWF models continue to predict that a tropical storm will form between Africa and the Lesser Antilles Islands sometime in the period 3 – 6 days from now. There is an area of disturbed weather south of the Cape Verdes Islands, but there is no obvious organization to the cloud pattern. Wind shear is a hefty 20 – 30 knots in the region, and the disturbance is a 1 – 2 day journey away from reaching a lower shear area where development can occur. Preliminary indications are that if a storm did develop in this region, it would track west-northwest and pass well to the northeast of the Lesser Antilles Islands 7 – 8 days from now. However, 7-day forecasts of a storm that hasn’t even formed yet are not to be trusted.”

I have taken the liberty of trimming the latest full disc color satellite image down to a manageable size where you can still easily find Florida and thus look across the Atlantic to see the area of disturbed weather off Africa to which Dr. Masters refers. Two independent left clicks on this image will enlarge it fully. This image was taken from a distance over three earth diameters away from the surface yet there is considerable detail.  I hope you enjoy it.