Hurricane Bertha: July 12 Update A

After working hard all week, Bertha is enjoying a relaxing weekend -
just like me :).

She is very slowly drifting northwards at 2mph. Her central pressure is
983mb and she has winds speeds of 80 mph, which still keeps her as a cat
1storm (74-95mph). Even though she is supposed to be over water
temperatures of 27-28 deg C, because she has been almost stationary I'm
sure the water temperatures beneath are a bit cooler by now. In some
images you can see the path she took as she crossed the Atlantic because
the sea surface temperatures in her wake are cooler than the surrounding
waters. So, with what we assume are cooler waters below, it is unlikely
that she will intensify much until she starts moving again and at that
point we'd have to assess what the atmosphere is like as well to figure
out if she will re-intensify at all.

She is now almost at 30N, 62.5W. Wind shear is still low, and the
convection is not very symmetrically distributed. Her cloud tops are
fairly warm in large parts of the storm. The northern edge has the most
convective activity (and cooler cloud tops) at the moment - that is
where she is interacting with the warmer water ahead of her. For a reminder
explanation of cloud tops look at the July 9, update C in the archives.

I hear the Bermuda research cruise departure has been postponed to
Monday morning... right around the time when Bertha will be closest to
the island if she continues as forecast. What are the waves now... 10ft?
That should be oodles of fun.

I won't send out another update today unless there's some change.
Bye for now,
J.

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-------------------------------
DISCLAIMER:
These remarks are just what I think/see regarding tropical storms - not
the opinion of any organization I represent. If you are making an
evacuation decision, please heed your local emergency management and
the National Hurricane Center's official forecast and the National Weather
Service announcements. This is not an official forecast. If I "run away,
run away" (Monty Python), I'll let you know.
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Hurricane Bertha: July 11 Update B

It looks like she's made that little bit of a northward turn and is
"zipping along" in a N-NW. Now when I say "zipping along" I mean moving
forward at a fast pace relative to a snail... she's got a grand forward
speed of 4mph. She is encountering that high pressure and the poor
little thing is struggling really hard to move northward. Umm... but
this doesn't necessarily mean that she will avoid Bermuda altogether.

She's intensified slightly since this morning and now has winds of 90
mph (compared to the 85 mph earlier), but this still makes her a strong
cat 1 (wind range 74-95 mph). They finally sent in a plane to
investigate the storm this afternoon and have much better observations
on what is going on. Her central pressure is 976mb. The NHC do not
forecast a strengthening in the next few hours - although they have said
there is a possibility. I think it is very likely that she will become
stronger! She is already looking better, with stronger convection
occurring all around the eye (although the eye could do with some
polishing up yet). She is over water temperatures of 27-28 deg C,
although the depth of those warm waters is quite shallow. She is also in
a low-wind environment - all these indicate some further intensification
to me.

The other thing I do not agree with the NHC about at the moment is me
is that she will weaken in 36 hours as she moves over cooler temperature
...of what, 27-28 deg C?? - unless she picks up forward speed very
rapidly, or makes a sharp right turn and moves quickly I don't see the
'cooler temperature' waters they are referring to. As for picking up
speed, the models have her pretty much just loitering about
(mischievously of course - can one loiter any other way?) for a day or
two as she tries to get past this high. Scenario one from yesterday -
getting swept along that low pressure system - is not going to happen.

Meanwhile, back on Bermuda ... our intrepid reporter told me they loaded
the research vessel in preparation for departure in a couple of days and
now he's off to play a round of golf. Dum-de-dum... another normal day
in Bermuda (other than the tropical storm watch and closing of the south
beaches).

Have a wonderful weekend (this hopefully applies to people in Bermuda as
well). Unless something exciting happens tonight, I'll send something
out tomorrow.
Bye for now,
J.

P.S. I know a lot of new people have been 'dropping by' and reading this
so if you have any questions (or I am being incomprehensible :) ), then
do let me know.

Blogs archived at: http://www.jyotikastorms.blogspot.com/
-------------------------------
DISCLAIMER:
These remarks are just what I think/see regarding tropical storms - not
the opinion of any organization I represent. If you are making an
evacuation decision, please heed your local emergency management and the
National Hurricane Center's official forecast and the National Weather
Service announcements. This is not an official forecast. If I "run away,
run away" (Monty Python), I'll let you know.
-------------------------------------------

Hurricane Bertha: July 11 Update A

There wasn't much change in Bertha's track or intensity yesterday... she
has winds of about 85mph and is therefore still a mid-sized cat 1 (wind
range: 74-95mph), and she continues to move in a NW direction.

She did slow down, and is now chugging along at about 6mph, which
indicates that she continues to bump up against a higher pressure region
in front of her (was it the Little Engine That Could that went slowly up
the hill or was it Thomas the Tank Engine?). Although there is still an
eye, it is not as well formed as it was 24 hours ago. But there is good
circulation in this system, now extending into the higher levels of the
troposphere (lowest level of the atmosphere). Despite the nice
circulation the convective activity is not very well distributed and
this morning it is mostly on the west side. Without better observations,
the best guess (mine, the NHC, the models) is that she will remain a cat
1 today.

She's currently at about 28.2N, 61.7W and the computer models are in
agreement that she will continue her NW track until she is at about 30N.
After that point they diverge, but all remain on the east side of
Bermuda. Some even forecast that she will stall. The NHC will probably
issue a Tropical Storm Watch for Bermuda later today.

I am waiting for her to get to about 30N before I can assess which of
the three scenarios I presented yesterday will really kick in. Until
then, she's going NW and towards Bermuda.

She is in a region of low wind shear, and also over water temperatures
of about 27-28 deg C. But just north of 30N, she will encounter warmer
temperatures of 28-29 deg C.

There is insufficient data to be able to make a really good call on her
track at this point - and this is the problem with both the track and
intensity forecasts. There are not enough observations at a high enough
resolution. With the right type of data at the right resolution,
hurricane forecasts would be much improved... and then you'd all have
more time to do interesting things like washing your hair or watching
the grass grow instead of reading this blog :)

For those wondering what those hardy Bermudians are going to do about
their research cruise - last I heard it had been pushed back to Sunday.
Maybe I'll get an update today... and if they do go out, we might get
some live "in the field" reports. I suppose it's one way to lose weight...

More later,
J.

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-------------------------------
DISCLAIMER:
These remarks are just what I think/see regarding tropical storms - not
the opinion of any organization I represent. If you are making an
evacuation decision, please heed your local emergency management and the
National Hurricane Center's official forecast and the National Weather
Service announcements. This is not an official forecast. If I "run away,
run away" (Monty Python), I'll let you know.
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Hurricane Bertha: July 10 Update A

I should never have called her Boring Bertha a few days ago. I'm sorry
Mother Nature. I take it back.

Intensity:
So... the Really Very Incredibly Interesting Bertha is now weakening
again and has winds of 90mph, making her a strong cat 1 (74-95mph
range). I hope you all remembered my 'warm cloud top' discussion from
yesterday? Well, that was a sign of the weakening, and since then the
cloud tops have become warmer so there is not a lot of convective
activity going on in this system. She is still surrounded by dry air,
and some of that is getting entrained. However, she is still over waters
of 27-28 deg C and in a low wind-shear environment, and dynamically she
is still very good looking (she still has an eye), so I am not sure if
she will weaken much more today and she there is a good possibility that
she'll get a bit stronger - and that is also the thinking of the NHS,
who are finally not solely relying on the models:

"THE INTENSITY FORECAST IS A CONUNDRUM. <talk about models>... THE
INTENSITY FORECAST WILL BUCK THE MODEL GUIDANCE AND CALL FOR SLIGHT
STRENGTHENING DURING THE FIRST 24-36 HR."

Track:
This is also becoming trickier by the hour. Given her slower forward
speed of 9mph it looks like she is moving against an area of higher
pressure (going up hill slowly). There are three scenarios:
1. there is now an area of low pressure moving off the US and into the
Atlantic. IF that moves fast enough and she gets north enough in the
next day or two, she will interact with it and move northward - but
where exactly that interaction will occur is uncertain. However, the
computer models at the moment are predicting that she will not interact
with this low.
2. she manages to get around the high she is now bumping against and
moves N-NW and then N soon
or,
3. she will continue to move in a NW direction and to the west of her
current track as she tries to get around this high pressure system
(remember, in the Northern Hemisphere, things move clockwise around a
high pressure system).

Her forward speed provides a clue about the state of the atmosphere -
slower speeds indicate that she is encountering a high pressure ahead of
her, and so the chance that the track will be to the left of the current
center of the cone is greater.

Let's see what happens during the rest of today.

I hear that the surf is now good in Bermuda - and tomorrow the east
coast of Florida should see some nice surf...
J.

Blogs archived at: http://www.jyotikastorms.blogspot.com/
-------------------------------
DISCLAIMER:
These remarks are just what I think/see regarding tropical storms - not
the opinion of any organization I represent. If you are making an
evacuation decision, please heed your local emergency management and the
National Hurricane Center's official forecast and the National Weather
Service announcements. This is not an official forecast. If I "run away,
run away" (Monty Python), I'll let you know.
-------------------------------------------

Hurricane Bertha: July 9 Update C

Big Beautiful Bertha - she's now a large cat 2 with sustained winds of
105 mph and a minimum pressure of 970 mb (cat 2 winds: 96-110mph). She
is back on a NW track and is moving at 12 mph - so although the track
east of Bermuda is still looking like a good scenario I would make
preparations though (and I don't mean cruise preparations!) because she
will grow, and the track forecast is still dodgy after tomorrow - we now
need her to make that N-NW turn and sustain it, and the sooner the
better. She's at lat. 24.8N, 58.1W, still surrounded by dry air, but
hanging out over water temps of 27-28 degc C and in a low wind shear
environment.

Interestingly, for such a good looking and strong storm her clouds tops
are fairly "warm". What does that mean? It means that the tops of her
clouds are not as high up in the troposphere (the lowest section of our
atmosphere) as they could be. The troposphere is characterized by
cooler air temperatures the higher up you go. So the higher the clouds,
the colder their tops, and that's an indication of some very very strong
(or deep) convective activity (large thunderstorms etc). If you look at
a color infrared image of a hurricane (there are some in the "satellite"
link on left side of the NHS webpage), the coldest clouds tops are
indicated by red. The last time Bertha was this size a couple of days
ago, if I recall correctly, her cloud tops were cooler - and they
certainly were red when she was a cat 3. So she is not yet as deep into
the troposphere as she could be.

That's all for today (unless there's any major change tonight).
Ciao,
J.

P.S. I know the blog/wrap-around text problem did not get resolved -
we'll try something else tomorrow. Oh well... it still looks nicer than
it did. :)

Blogs archived at: http://www.jyotikastorms.blogspot.com/
-------------------------------
DISCLAIMER:
These remarks are just what I think/see regarding tropical storms - not
the opinion of any organization I represent. If you are making an
evacuation decision, please heed your local emergency management and the
National Hurricane Center's official forecast and the National Weather
Service announcements. This is not an official forecast. If I "run away,
run away" (Monty Python), I'll let you know.
-------------------------------------------

Hurricane Bertha: July 9 Update B

Bertha is getting Bigger. Again. Deja vu anyone?

In the 11am advisory, about 2 hours ago the NHS kept Bertha as a cat 1
storm (which I agree with) with about 75mph winds (which I disagree with
- I think they were stronger, even back then) and a central pressure of
987mb.

Intensity: She is intensifying again and an eye has formed. She may even
become a cat 2 by the end of today because she is back to being
Beautiful Bertha. There's a chance for a cat 3 too, but that sort of
very rapid intensification is currently difficult to predict. She is
over 27-28 deg waters in a low wind shear environment (other than to her
north-east) and is not only growing in intensity, but also in size
despite the dry air surrounding her.

Track: She is now officially heading in a W-NW direction at 12 mph and
is located at around 24.5N, 58W so she is ~700 miles SE of Bermuda. It
is a little tricky to judge, but they may have shifted the track a
little to the west - the next advisory at 5pm will be a bit clearer I
think. We really are looking for her to resume that NW motion, and then
N-NW so she stays east of Bermuda.

Both the track and intensity forecasts are now a little dodgy after the
next day or two - the models are not quite as tightly confined as they
have been so far. I am not too surprised by this.

For those following what's going on there from my previous entry - the
research cruise has now been pushed back to Sunday morning. Currently
the forecast is for Bertha will be in the vicinity Sat/Sun...

I'll send out another update later, after the 5pm advisory.
J.

P.S. For those of you looking at the blog on the website, thanks for
complaining about the format of the text (AA) ;). Coincidently, my
wonderful web-guru and pal, CH, decided he needed to take action as well
because otherwise I'd never get anywhere. So I am hoping this entry will
look much nicer than all the rest. I've also added some
hurricane-related links to the site now. And one day, I may even be bold
enough to add an image! (I can hear your collective gasps of amazement
you know) - but let's not rush into this fancy-schmancy technology too
quickly hey? :)

Blogs archived at: http://www.jyotikastorms.blogspot.com/
-------------------------------
DISCLAIMER:
These remarks are just what I think/see regarding tropical storms - not
the opinion of any organization I represent. If you are making an
evacuation decision, please heed your local emergency management and the
National Hurricane Center's official forecast and the National Weather
Service announcements. This is not an official forecast. If I "run away,
run away" (Monty Python), I'll let you know.
-------------------------------------------

Hurricane Bertha: July 9 update A

Building Bertha - I know, I am scrapping the bottom of the barrel here are
for alliterations. If I get them all out now, you may be spared from such
silliness later in the season. Or perhaps not :) Right... down to
Bertha-Business:

Intensity:
The 5AM NHS advisory this morning says that Bertha looks like she is
getting better formed and the vertical shear may be decreasing - which is
what I said yesterday. Despite a better looking storm (much better than
the 'cat 2' they had her at yesterday), they have continued to lower her
wind speed to 75 mph, so barely at hurricane strength (cat 1: 74-95mph). I
do agree with her cat 1 status and I think that we'll see some
intensification to a strong cat 1, also in agreement with the NHS.
Although still surrounded by dry air, the water underneath is 27-28 deg
C., and she is in a region of low wind shear.

Track:
So far the track models have been pretty good as they have forecast her
move around the clearly defined Bermuda/Azores High. They still keep her
to the east of Bermuda - moving past in about 4 days - but I am not as
certain of this as I was yesterday. She's at 23.5N, 56.5W, her forward
speed has slowed down to 10mph, and the NHS say she is moving in a NW
direction. I did some quick calculations (because I'm a geeky scientist)
and it looks like she is moving more on a W-NW trajectory now and has been
since yesterday - this brings her track closer to Bermuda (~lat: 32.3,
long: 64.8W) so we may see the envelope shift westward.

The track forecast may be about to get a bit more complicated though, as
there is a second high pressure system moving off the US into the
Atlantic. The ideal situation is for Bertha to pass between the two high
pressure systems (in a lower pressure area known as a trough), but because
she is slowing down I am wondering if she is actually already interacting
with this second high, which will continue to keep her west of the current
forecast track - hence the possible westward movement of the track
envelope. I don't have a fine enough resolution pressure field to be able
to see this so we will have to watch what happens in the next 24 hours.

So, to sum up: if you are still planning on a research cruise on Saturday
out of Bermuda the most helpful advice I can provide is... don't forget
your sea-sickness aids :)

Another update later...
J.

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-------------------------------
DISCLAIMER:
These remarks are just what I think/see regarding tropical storms - not
the opinion of any organization I represent. If you are making an
evacuation decision, please heed your local emergency management and the
National Hurricane Center's official forecast and the National Weather
Service announcements. This is not an official forecast. If I "run away,
run away" (Monty Python), I'll let you know.
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[Jyo_hurricane] Hurricane Bertha: July 8 Update B

I was disappointed with the NHS forecast earlier today. At 11am they
downgraded Bertha to a cat 2 (winds of 96-110mph) when she was clearly
far less than that by 9.30am this morning with no eye, not very good
convection etc. So for the past six hours she was officially and wrongly
classified as a cat 2, which troubles me. However, the latest 5pm
advisory has her as a cat 1 (winds of 74-95mph), which I agree with.
The NHS acknowledges that their intensity forecasts have been way off.

She is now at 22.7 N, 54.8W and heading NW at 12mph. Maximum winds are
85mph and they forecast continued weakening in the next few hours but
keep her as a cat 1 for the next two days. To me, she looks like she has
intensified slightly since this morning (which is why I agree with their
cat 1 assessment) and she is now back over warmer waters of 27-28 deg C
and is entering a region of lower wind shear. Dry air is still being
entrained into the storm, but she is trying to regain some of her steam
(all puns always intended :) ).

It still looks like she will pass east of Bermuda, but you Bermudians
should still keep an eye out in case something happens that wasn't
forecast - although really, how often does that occur, hey?... umm...
never mind.

I hear that the surf will be wonderful over there soon...(and suddenly
all flights to Bermuda are fully booked). By the way, I had no idea how
many people were surfers on this list. Let me know if you would like me
to introduce you to each other. :)

If there are any major changes I'll send out another update later,
otherwise until tomorrow amigos...
J.

Blogs archived at: http://www.jyotikastorms.blogspot.com/
-------------------------------
DISCLAIMER:
These remarks are just what I think/see regarding tropical storms - not
the opinion of any organization I represent. If you are making an
evacuation decision, please heed your local emergency management and the
National Hurricane Center's official forecast and the National Weather
Service announcements. This is not an official forecast. If I "run away,
run away" (Monty Python), I'll let you know.
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[Jyo_hurricane] Hurricane Bertha: July 8 update A

Although she's still officially a strong hurricane, I think she's going
to be Tropical Storm Bertha (39-73mph) in the next NHS advisory, or at
the very most a cat 1 hurricane (74-95mph). In the last ~6 hours, she
has steadily collapsed from being a strong cat 3 storm (111-130mph) with
winds of 120 mph and central pressure of 955mb to a system that does not
have an eye, has poor convective activity and is entraining dry air. She
is still over waters of 26-27 deg C, but has entered a region of higher
wind shear.

She is also going to pass well east of Bermuda - which is what I thought
and it is also in agreement with the computer models. The current center
of the cone will be shifted eastward again. At the last advisory she was
moving to the NW at 10mph - I think she's now moving N-NW.

Once again, the official intensity forecasts are 'a bit off' - they had
her maintaining cat 3 status throughout the day today, dropping to a cat
2 tomorrow. Given her collapse and surrounding atmospheric
environmental conditions I don't see her re-intensifying to a cat 3, and
I expect the NHS to downgrade her quite rapidly in the next couple of
hours. This storm has really demonstrated the amount of work that still
needs to be done in order to get a handle on the intensification of a
tropical storm.

I will send out another update later today. Have a lovely day :)
J.

Blogs archived at: http://www.jyotikastorms.blogspot.com/
-------------------------------
DISCLAIMER:
These remarks are just what I think/see regarding tropical storms - not
the opinion of any organization I represent. If you are making an
evacuation decision, please heed your local emergency management and the
National Hurricane Center's official forecast and the National Weather
Service announcements. This is not an official forecast. If I "run away,
run away" (Monty Python), I'll let you know.
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[Jyo_hurricane] Hurricane Bertha: July 7 update C

I think Bertha is having fun with the intensity forecasts being made :)
- although forecast to be a cat 2 in the 11am advisory, the 5pm NHS
advisory has her as a major hurricane category 3 storm (winds range:
111-130mph). Her wind speed is now 115mph, which is quite remarkable for
a storm that is surrounded by dry air and only over water temperatures
of 26-27 deg C. (she's moved back over slightly cooler waters since my
last update). She's at ~20.2N, 52.1 W and is moving W-NW at 12mph now,
so she has slowed down quite a bit. Minimum pressure has dropped to 948 mb.

The track is still something to keep an eye on, but it does look like
she's moving more northward of the official W-NW heading which will take
it east of Bermuda, but just in case... if you are in Bermuda, I hope
you are getting ready!

That's all for today folks. More tomorrow.
J.

Blogs archived at: http://www.jyotikastorms.blogspot.com/
-------------------------------
DISCLAIMER:
These remarks are just what I think/see regarding tropical storms - not
the opinion of any organization I represent. If you are making an
evacuation decision, please heed your local emergency management and the
National Hurricane Center's official forecast and the National Weather
Service announcements. This is not an official forecast. If I "run away,
run away" (Monty Python), I'll let you know.
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[Jyo_hurricane] Hurricane Bertha: July 7 Update B

Beautiful Bertha gets Bigger (how's that for a news headline? am I in
the wrong field? :) ) ... she has intensified and the NHS now agrees
with what I wrote earlier - she will continue to intensify and become a
cat 2 (wind range: 96-110mph). Their next advisory is at 5pm, but it
looks to me like she is already a cat 2. The last advisory at 11am had
her with 90 mph winds and she was a smaller, weaker storm at that point.
Her diameter has grown quite noticeably in the last few hours, with a
solid ring of convection around a very clearly defined eye - she really
is a good looking system. There is still wind shear to the north-east,
which is why if you see a satellite image of her (for example,

http://www.ssd.noaa.gov/goes/flt/t1/vis.jpg), you will see a stream of
activity extending off her north-east quadrant. But despite that and the
dry air surrounding her, the low wind shear around other parts of the
storm and the warm waters underneath are really kicking in.

This storm is great and well-timed for two reasons:
1. It demonstrates that we (as a hurricane science community) still do
not fully understand what makes tropical storms intensify because if we
did then the models would have forecast this intensity, but as late as
24 hours ago they were still predicting that today she would be a
Tropical Storm.
2. Although the models improve every year, this gives us a benchmark for
the rest of the season as far as the intensity models are concerned, and
for this year their forecasts may still be off within any 24-hour window.

She's at about 20N, 51.5W, moving W-NW at about 15mph with a central
minimum pressure of 975 mb. Interestingly, the circulation still does
not extend up through the entire troposphere. The troposphere is the
lowest section of our atmosphere and in the tropics it extends to about
16km above the earth's surface (oooh... aaah... science :) ). There is
now, however, a clear circulation (vorticity) at the mid-levels of the
troposphere. The really large storms have a clear circulation all the
way to the top boundary of the troposphere, which is called the tropopause.

I'll probably send out another update after the 5pm advisory is out.
Isn't this exciting? :)
J.

Blogs archived at: http://www.jyotikastorms.blogspot.com/
-------------------------------
DISCLAIMER:
These remarks are just what I think/see regarding tropical storms - not
the opinion of any organization I represent. If you are making an
evacuation decision, please heed your local emergency management and the
National Hurricane Center's official forecast and the National Weather
Service announcements. This is not an official forecast. If I "run away,
run away" (Monty Python), I'll let you know.
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[Jyo_hurricane] Hurricane Bertha: July 7 update A

Great googliemooglies... I knew as soon as I called her 'Boring Bertha'
that she would start to change - it was like throwing down the gauntlet.

Although she is a hurricane (cat 1 wind range 74-95mph), she was barely
one when they upgraded her from a TS to a hurricane early this morning.
The wind speeds are calculated from satellite information, not from in
situ data within the system, so they are not very accurate. The discussion
from the NHS this morning says:

"OBJECTIVE DVORAK ESTIMATES REMAIN SLIGHTLY BELOW THE HURRICANE
THRESHOLD...BUT GIVEN THE MICROWAVE SIGNATURES THE SYSTEM IS UPGRADED TO A
HURRICANE..."

The Dvorak technique is used to estimate the wind speed from satellite
data. Although their calculations showed winds of slightly less than
hurricane strength, the images showed an eye so she was upgraded. I'll
ramble about the Dvorak technique in a later entry.

In this case we were all wrong - the NHS (and models) yesterday forecast
her to reach hurricane strength 24 hours from now (Tues am), and I did not
think she would quite make it and would remain a very strong TS.

She is now at about 19.5N, 50.5W and is moving in a W-NW direction at 17
mph. She will clear the Caribbean, but how far west she moves before
curving into the Atlantic is still debatable. The reason the system is
slowing in forward motion is because she is bumping up against that high
pressure - it's like anything moving up a hill, a bit slower depending on
how steep the gradient is.

There is a well-defined eye and she is looking good: Beautiful Bertha :)
The circulation is not very deep into the atmosphere, so although she
looks good, she is still a very weak cat 1.

She is almost completely surrounded by dry air, so the moisture is
predominanatly coming from evaporation from the ocean. Temperatures
underneath are 26-27 degs C, but within a few hours she will be over water
temperatures of 27-28 deg C, and given the slower forward motion and her
recent intensificaton, it looks likely that she will get stronger. The
wind shear is not very high this morning (except at the north-eastern edge
of the storm) and it does not look like it will get much stronger in the
next 24 hours. The NHS forecast keeps her as a cat 1 storm though.

In 1996 a previous incarnation of Bertha became a Hurricane on July 7.

More later today.
J.

Blogs archived at: http://www.jyotikastorms.blogspot.com/
-------------------------------
DISCLAIMER:
These remarks are just what I think/see regarding tropical storms - not
the opinion of any organization I represent. If you are making an
evacuation decision, please heed your local emergency management and the
National Hurricane Center's official forecast and the National Weather
Service announcements. This is not an official forecast. If I "run
away, run away" (Monty Python), I'll let you know.
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[Jyo_hurricane] TS Bertha: July 6 update A

As expected, there has been little change in TS Bertha: winds of ~50mph,
central pressure of 1000mb, still moving in a general westward direction
at 21 mph. Thankfully Boring Bertha and let's hope she stays that way (by
the way, I may not be politically correct but that is not a commentary on
any person called Bertha!). :)

Her current location is around 18N, 46W - she is not very well defined so
it is difficult to identify her center of circulation. I think she's a
little north of where the NHC would place her, and it looks like she will
continue westward for another day but the NHC/models predict a
northwestward motion sooner than that (which would be good).

There is still dry air to the north, south and west of her and she is now
entering a region of moderate-to-strong wind shear for something her size
- so the atmospheric conditions are not conducive to much growth. On the
other hand, the ocean conditions are becoming favorable - she is over
water temperatures of 26 deg C, and heading towards temps of 27 deg C. I
think there will be a little strengthening, but not too much. The NHC
forecasts that she will reach hurricane strength by Tuesday morning. Given
her current trajectory, I am not convinced about this yet. Unless the
atmospheric conditions change I think she may remain a TS for the next few
days.

If anything changes I'll send out another update today, otherwise tomorrow
it is. Enjoy your sunday and I'm sure you are all looking forward to going
back to work tomorrow after this lovely long weekend... :)

A bientot,
J.

Blogs archived at: http://www.jyotikastorms.blogspot.com/
-------------------------------
DISCLAIMER:
These remarks are just what I think/see regarding tropical storms - not
the opinion of any organization I represent. If you are making an
evacuation decision, please heed your local emergency management and the
National Hurricane Center's official forecast and the National Weather
Service announcements. This is not an official forecast. If I "run
away, run away" (Monty Python), I'll let you know.
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[Jyo_hurricane] TS Bertha: July 5 update B

Not much has changed since the last update other than Bertha's location -
she is now at ~16.7N, 40W. All else is the same: winds are about 50mph,
central pressure 1000mb, still moving westward at 21 mph and is over water
temps of about 25 deg C, the wind shear is still moderate, and there is
still dry air to the north, south and west. She remains disorganized with
convection only to the north-east of the center - and it is not very
strong. Later tonight/early tomorrow she will move over warmer waters of
26 deg C and things will begin to change. I think she will maintain her
westward heading for another day at least.

J.

Blogs archived at: http://www.jyotikastorms.blogspot.com/
-------------------------------
DISCLAIMER:
These remarks are just what I think/see regarding tropical storms - not
the opinion of any organization I represent. If you are making an
evacuation decision, please heed your local emergency management and the
National Hurricane Center's official forecast and the National Weather
Service announcements. This is not an official forecast. If I "run
away, run away" (Monty Python), I'll let you know.
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[Jyo_hurricane] TS Bertha: July 5 update A

Bertha is now at 16.6N, 37.3 W and, like many women this weekend, she is
clearly in a rush to get to the Independence Day sales before they end
because she is moving at a very rapid 21 mph in a westward direction...
and that, my friends, is the slightly troubling aspect of this storm - the
westward direction. The high pressure system is holding firm and does
extend across the Atlantic now, so there is a chance that she could clip
the northeastern Caribbean. The point where she will make that
north-west/north/north-east curve out into the Atlantic is not very clear
at the moment.

The good news is that there has not been a change in intensity since
yesterday - winds are just below 50mph and central pressure is 1000mb. She
is still moving over cool water temperatures of 25-26 deg C but if she
maintains her fast movement she will be entering waters of 26-27 deg C in
about 20 hours.

In the atmosphere, there is dry air to her north, west, and south, which
is also preventing her from blossoming. However, the wind shear is not as
strong now and won't be for at least another day.

The path she takes in the next few days will determine her intensity.

I'll send out another update later, so stay tuned... unless you are at the
shops ;).
Ciao,
J.

Blogs archived at: http://www.jyotikastorms.blogspot.com/
-------------------------------
DISCLAIMER:
These remarks are just what I think/see regarding tropical storms - not
the opinion of any organization I represent. If you are making an
evacuation decision, please heed your local emergency management and the
National Hurricane Center's official forecast and the National Weather
Service announcements. This is not an official forecast. If I "run
away, run away" (Monty Python), I'll let you know.
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[Jyo_hurricane] TS Bertha: July 4 Update A

As expected, there has been little change in the intensity of TS Bertha -
she now has winds of 50mph (TS winds: 39-74 mph). So a low-to-mid-sized
TS.

The good news is that the wind shear has been kicking in since yesterday
and making the storm a little lop-sided with the north-west quadrant
devoid of convection. She is also moving in an area of drier air, and
maybe some of that is getting pulled into the storm (entrained is the
technical jargon). She is moving over colder waters of 25 to 26 deg C,
which is cooler than the temperatures needed to maintain a storm (26.5 deg
C). All these factors will keep her intensity steady or may even decrease
it in the next day or two.

The track is a little more westward than expected because the high
pressure has expanded a little westward - so that is something to keep an
eye on. But her heading is still the same as yesterday: W-NW and she's
moving faster now at a rather quick 18mph. I hope things will be clearer
tomorrow.

She's at 15.5N, 31.6W. It is difficult to see her center because she is
not a very well organized storm, so I will go with the official center -
which the NHS has been shifting a few times over the past day as they got
more information.

I'm only sending out one note today because it's a holiday and not much
has happened really... to the storm anyway... I, on the other hand, had an
adventure with a snake (in my car!!!), and saw an 8ft alligator stalk and
eat a turtle! Why am I living in Florida again??

Hope you all have a great July 4!
J.

Blogs archived at: http://www.jyotikastorms.blogspot.com/
-------------------------------
DISCLAIMER:
These remarks are just what I think/see regarding tropical storms - not
the opinion of any organization I represent. If you are making an
evacuation decision, please heed your local emergency management and the
National Hurricane Center's official forecast and the National Weather
Service announcements. This is not an official forecast. If I "run
away, run away" (Monty Python), I'll let you know.
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[Jyo_hurricane] Tropical Storm Bertha: July 3 Update B

As expected, the 11am NHC advisory upgraded TD2 to TS Bertha. She has
winds of around 40 mph (TS: 39-74 mph), and they have a better handle on
her center of circulation they say, which is at 13.3N, 24.7W, located
190 miles south-southwest of the Cape Verde Islands. She's still moving
in a WNW direction at about 14 mph and her minimum pressure is now 1006 mb.

And now for a bit of background science before the track discussion. For
those of you who have been with me for the start of previous seasons,
this is a refresher.

In the northern hemisphere, things move clockwise around a high pressure
system, and counter-clockwise around a low pressure system. These
storms are generally steered by the larger scale atmospheric pressure
fields. Over the Atlantic there is a large pressure system called the
Bermuda/Azores High and this is a factor in the general steering and
track of these storms. Imagine a clock-face over the Atlantic. The storm
is currently moving from the 6 to 7 on the face, which is the W-NW
track. It will then shift to a NW track (7-8 numbers on the face), then
N-NW (8-9) and so on as it curves out and away from the N. American
continent.

At the moment, this high pressure is confined to the eastern Atlantic.
So, I agree with the computer models and the NHC that given the current
large scale atmospheric pressure fields this storm will curve out in the
Atlantic in a few days.

If anything changes today, I'll send out another update otherwise you'll
hear from me tomorrow. Have a lovely day :)
Ciao,
J.

Blogs archived at: http://www.jyotikastorms.blogspot.com/
-------------------------------
DISCLAIMER:
These remarks are just what I think/see regarding tropical storms - not
the opinion of any organization I represent. If you are making an
evacuation decision, please heed your local emergency management and the
National Hurricane Center's official forecast and the National Weather
Service announcements. This is not an official forecast. If I "run
away, run away" (Monty Python), I'll let you know.
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[Jyo_hurricane] Tropical Depression 2: July 3 Update A

Before we start talking tropical weather, let's get the important things
out of the way: welcome to all the new people who have signed up since
my last update (which was about a month ago). If you have any questions
please don't hesitate to send me an email and if you are lucky, I might
even know the answer ;)

Now on to the trivial stuff: I know a few of you have been watching the
'Blob' (a highly technical term I sometimes use) that came off the coast
of Africa about 3-4 days ago. It looked really beautiful for something
that was just developing. Well finally, after days of watching it not do
much other than look pretty, last night it was officially designated
Tropical Depression (TD) 2 by the National Hurricane Center (NHC).

TD 2 is at about 12.6N, 22.7W, traveling W-NW at 9mph. Central pressure
as of early this morning was 1008 mb, and wind speeds were at about
35mph (55km/hr). I expect this will probably become a Tropical Storm
(TS) within 24 hours - most likely today (that would be TS Bertha) - TS
winds range from 39-73 mph.

However, even though this system is still way out there, there are some
signs that for the next few days it may not develop too rapidly. It is
in a region of moderate wind shear and although it is currently over
water temperatures of 27-28 deg C the depth of that warm water is really
shallow so it will be churning up colder water not warm water. It is
heading to cooler surface waters of 26-27 deg C, but that's still warm
enough to at least maintain a storm if all other conditions were favorable.

I'll talk about the path it will take in the next update later today.

I hope everyone is prepared for hurricane season - wine, beer,
non-perishable food, water, a good book, some ice cream, pina coladas,
sunscreen, bug spray, swim suit .. oh wait, no, sorry that's the
checklist for a picnic on the beach....

J.
-------------------------------
DISCLAIMER:
These remarks are just what I think/see regarding tropical storms - not
the opinion of any organization I represent. If you are making an
evacuation decision, please heed your local emergency management and the
National Hurricane Center's official forecast and the National Weather
Service announcements. This is not an official forecast. If I "run away,
run away" (Monty Python), I'll let you know.
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[Jyo_hurricane] June 1: The "official" start of the 2008 Hurricane Season... and TD Arthur

Hello my friends,

And we're back! Welcome to the first "official" day of the Hurricane
Season of 2008. I've not had access to the internet since Thursday (May
29) afternoon... did I miss anything? ;)

O.k. so although I couldn't log in because I have an uncooperative
computer, I did follow what was going on with TS Alma-call-me-Arthur via
the tv "news coverage" (in Key West, where I went for work on Friday.
Really. I did. It was work. I know, it's a tough life...).

Arthur is now a Tropical Depression over Mexico, heading west-southwest
(and hopefully won't emerge into the Pacific again!) with weakening winds.

Watching the media, I suppose the scariest spin that they could have
possibly put on a (barely) tropical storm not heading to the US is that
"Mother Nature has started the Atlantic season early because TS Arthur
formed the day before June 1." (to paraphrase a number of different
stations). Thereby implying a season like no other.

No, not a WHOLE DAY!! Once again Mother Nature shows her disregard for our
artifically imposed boundaries. How dare she?

Really, it's not a big deal that a storm formed at the end of May. June 1
to November 30 are days that were picked because they are easy to remember
and encompass ~99% of all known storms. I don't think the % would change
if we said the official Hurricane Season went from May 31 to November 29
... or wait for it, how about May 29 to November 27... ooh... how daring
would that be? Ho hum.

Unless Arthur upgrades to Tropical Storm Arthur, or has another identity
crisis and turns into TS Boris (the next Pacific storm name) I won't be
sending another note out until the next Atlantic system.

I hope everyone had a good off-hurricane season.
Ciao for now,
J.

Blogs archived at: http://www.jyotikastorms.blogspot.com/
-------------------------------
DISCLAIMER:
These remarks are just what I think/see regarding tropical storms - not
the opinion of any organization I represent. If you are making an
evacuation decision, please heed your local emergency management and the
National Hurricane Center's official forecast and the National Weather
Service announcements. This is not an official forecast. If I "run away,
run away" (Monty Python), I'll let you know.
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[Jyo_hurricane] Cyclopsychic Storm Detection: How forecasts are really made

Hello my friends,

I know I've come out of the annual winter hibernation a little early,
but I wanted to draw your attention to this article: "Cyclopsychic
research breakthrough proves hurricanes/global warming connection"
(http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=922&tstamp=200804).

As you might guess after reading this, I've been using the old
'cyclopsychic' techniques for a few years now, to look into the future
in forecasting storms. It's too bad that they let the cat out of the
bag. Is nothing to remain a mystery? Sigh. ;)

I hope everyone is having a good off-season. Back to hibernation for a
few more days ...

J.

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