Azores storm could become Subtropical Storm Alberto

By: Dr. Jeff Masters , 7:56 PM GMT on May 12, 2012

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An interesting and surprising hybrid low pressure system with both tropical and extratropical characteristics has formed over the far Eastern Atlantic, about 400 miles southwest of the southern Azores Islands. This low, designated Invest 92L by NHC today, has developed an impressive amount of heavy thunderstorm activity near its center, despite the fact that it is over cold ocean waters with temperatures of 66°F (19°C.) This is well below the 26°C usually needed for a tropical storm to form. However, there is quite cold air aloft, so the temperature difference between the surface the upper levels has been great enough to create sufficient instability for 92L to organize. Wind shear is a moderate 15 - 20 knots, and satellite estimates of 92L's winds were 63 mph at 1:45 pm EDT Saturday, according to NOAA/NESDIS. NHC estimated that 92L had top winds of 50 mph at 2 pm EDT Saturday.


Figure 1. Afternoon satellite photo of Invest 92L, taken at 16 UTC May 12, 2012, by NASA's Aqua satellite. Image credit: NASA.

NHC is giving 92L a 40% chance of developing into a named storm by Monday. They will be reluctant to name it Alberto unless the storm can maintain it's current level of heavy thunderstorm activity for at least 6 - 12 hours. The storm's heavy thunderstorms have weakened some during the afternoon, making it less likely NHC will be inclined to name it; the fact that 92L is over waters of 66°F (19°C) hurts its chances. The coldest waters I've seen a tropical storm form in were 19°C, during Tropical Storm Grace of 2009. Grace holds the record for being the farthest northeast forming tropical cyclone in the Atlantic basin. Like 92L, Grace also formed near the Azores Islands, but in early October. The coldest waters I've seen a hurricane form in were 22°C, for Hurricane Epsilon of 2005. Latest guidance from the computer models show 92L meandering to the south of the Azores through Monday, then beginning a slow motion towards the northeast by Tuesday.

Jeff Masters

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Likely was a tornado in Pensacola.
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Member Since: September 3, 2011 Posts: 13 Comments: 3482
Quoting Tazmanian:




if EL Nino is froming it wil make thing less activity for the atlantic and more activity for the E PAC

The + SOI means La Nina from what it sounds like...and so they are saying its more like ENSO neutral or La Nina. This is opposite of what was expected (El Nino)...
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Quoting stormhank:
If the SOI keeps goin upward wouldnt that signal a slower el nino forming? and tend to lead to more activity in atlantic??




if EL Nino is froming it wil make thing less activity for the atlantic and more activity for the E PAC
Member Since: May 21, 2006 Posts: 5096 Comments: 116630
Quoting stormhank:
If the SOI keeps goin upward wouldnt that signal a slower el nino forming? and tend to lead to more activity in atlantic??


The short answer is yes.

Here is an explanation about the SOI.

The Southern Oscillation Index, or SOI, gives an indication of the development and intensity of El Ni%uFFFDr La Ni%uFFFDvents in the Pacific Ocean. The SOI is calculated using the pressure differences between Tahiti and Darwin. The following figure demonstrates the typical fluctuations in SOI over a period of 11 years. Positive SOI values are shown in blue, with negative in orange. Sustained positive values are indicative of La Ni%uFFFDonditions, and sustained negative values indicative of El Nino conditions.Sustained positive values of the SOI above 8 may indicate a La Nina event, while sustained negative values below 8 may indicate an El Nino event. Values of between positive 8 and negative 8 generally indicate neutral conditions.

Link

Link
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Quoting yqt1001:
Convective pattern looks more like a developing STS now than the odd quasi tropical, subtropical and extratropical look earlier.


What about the banding type eye and cirrus outflow it had earlier today? That was more tropical looking IMO than it is now.... :)
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Good Evening; back from Cape Kennedy with the little one on a field trip and I see we have a unique invest out there. Way too early for the real deal but enclosing a link to an oldie but goodie; NOAA Mariner's Guide on Hurricanes. A nice general overview as to Atlantic Hurricanes and how they form, etc. with some interesting statistics; I have quoted from this source when folks get a little too excited over the the first waves as they start to exit from Africa.....The peak of the wave activity is usually in August and September (the classic Cape Verde portion of the season as the ITCZ rises towards the Caribbean) but only a very small percentage actually make topical storm status. I am enclosing the numbers quote and link below from the Guide. About 3 weeks to go for the start of the Atlantic Season but the start of the E-Pac season only a few days away.

Each hurricane season approximately 60 of these waves cross the tropical North Atlantic. Although the majority of these waves pass through the basin without any significant tropical cyclone development, passage of these waves is often accompanied by squally weather with brief periods of higher sustained winds.

Link

Happy Mother's Day tomorrow to the Lady Bloggers with Children.
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Quoting wunderkidcayman:

yeah that is the one that I said could very well become our first tropical wave when it first appared off of africa coupled of day ago

I wish I could pick out weak tropical waves...usually I rely on the NHC TAFB analyses to tell me where the waves are....this is something I want to get better at...

Quoting trHUrrIXC5MMX:
Atlantic - Caribbean Sea - Gulf of Mexico
Special Tropical Weather Outlook (en Español*)
140 PM EDT SAT MAY 12 2012 Tropical Weather Discussion
805 PM EDT SAT MAY 12 2012
There are no tropical cyclones at this time.

Eastern Pacific (out to 140°W)
Special Tropical Weather Outlook
1040 AM PDT SAT MAY 12 2012 Tropical Weather Discussion
2205 UTC SAT MAY 12 2012


no update yet! come on!

"NHC...you no give no outlooks?!"
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If the SOI keeps goin upward wouldnt that signal a slower el nino forming? and tend to lead to more activity in atlantic??
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oh if you are in the mark it too buy a Samsung Galaxy Tab do not get the 1st Samsung Galaxy Tab it will NOT get android 4.0 get the Samsung Galaxy Tab 2 it will come with android 4.0
Member Since: May 21, 2006 Posts: 5096 Comments: 116630
Atlantic - Caribbean Sea - Gulf of Mexico
Special Tropical Weather Outlook (en Español*)
140 PM EDT SAT MAY 12 2012 Tropical Weather Discussion
805 PM EDT SAT MAY 12 2012
There are no tropical cyclones at this time.

Eastern Pacific (out to 140°W)
Special Tropical Weather Outlook
1040 AM PDT SAT MAY 12 2012 Tropical Weather Discussion
2205 UTC SAT MAY 12 2012


no update yet! come on!
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Quoting Tropicsweatherpr:
Folks,maybe we may have the First Tropical Wave being introduced in the next day or two as that area around 35W if you look closely,has a faint inverted v signature on the clouds.


yeah that is the one that I said could very well become our first tropical wave when it first appared off of africa coupled of day ago
Member Since: June 13, 2009 Posts: 2 Comments: 14974
Quoting MAweatherboy1:

WHAT IS THE NHC DOING???? 92L is CLEARLY a sub-tropical storm! We need advisories NOW!!!!

:)


This reminds me of the meme someone posted many blogs ago:
"NHC...you no start advisories?!"

I don't have the funny picture that goes with it though...
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Folks,maybe we may have the First Tropical Wave being introduced in the next day or two as that area around 35W if you look closely,has a faint inverted v signature on the clouds.

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5 to 10 feet wave heights in the southern Caribbean
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Quoting nigel20:

Hey wunderkid...what's up?

umm nothing
Member Since: June 13, 2009 Posts: 2 Comments: 14974
Quoting wunderkidcayman:
I also noticed the SW caribbean is starting to get wetter with some covection now starting to pop


Hey wunderkid...what's up?
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BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE MOBILE AL
800 PM CDT SAT MAY 12 2012

THE NATIONAL WEATHER SERVICE IN MOBILE HAS ISSUED A

* TORNADO WARNING FOR...
SOUTH CENTRAL ESCAMBIA COUNTY IN NORTHWEST FLORIDA...

* UNTIL 830 PM CDT

* AT 759 PM CDT...A TORNADO HAS BEEN CONFIRMED. THE TORNADIC STORM
WAS LOCATED 3 MILES WEST OF WARRINGTON...OR 7 MILES SOUTHEAST OF
LILLIAN...MOVING NORTHEAST AT 20 MPH.

* LOCATIONS IMPACTED INCLUDE...
WEST PENSACOLA... WARRINGTON... MYRTLE GROVE...
GOULDING... BRENT... BELLVIEW...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A TORNADO HAS BEEN CONFIRMED. TAKE COVER NOW. FOR YOUR PROTECTION
MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A STURDY BUILDING.

&&

LAT...LON 3037 8735 3053 8731 3047 8720 3035 8730
TIME...MOT...LOC 0100Z 211DEG 19KT 3041 8730

$$
Member Since: February 11, 2012 Posts: 88 Comments: 8446
Quoting MAweatherboy1:

WHAT IS THE NHC DOING???? 92L is CLEARLY a sub-tropical storm! We need advisories NOW!!!!

:)


they are waiting for the storm to die,.....!!!!
lazy butts!
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Quoting Patrap:
www.nola.com/rivercam



Thanks Pat, another web cam and a cool one.....
Member Since: February 29, 2012 Posts: 0 Comments: 6865
I also noticed the SW caribbean is starting to get wetter with some covection now starting to pop

Member Since: June 13, 2009 Posts: 2 Comments: 14974
Quoting TropicalAnalystwx13:
The atmosphere of the blog will begin to change as 92L is now firing more convection.

WHAT IS THE NHC DOING???? 92L is CLEARLY a sub-tropical storm! We need advisories NOW!!!!

:)
Member Since: February 11, 2012 Posts: 88 Comments: 8446
May 12, SST's
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Quoting TropicalAnalystwx13:
The atmosphere of the blog will begin to change as 92L is now firing more convection.

Yes, just like earlier today when the blog moved from 1st gear to 3rd gear due to the improved structure of invest 92L at the time
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The atmosphere of the blog will begin to change as 92L is now firing more convection.
Member Since: July 6, 2010 Posts: 113 Comments: 34481
Quoting Tropicsweatherpr:


It keeps on the rising uptick now for almost two weeks.


I wonder how long this uptick will continue for
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Convective pattern looks more like a developing STS now than the odd quasi tropical, subtropical and extratropical look earlier.

Member Since: November 19, 2010 Posts: 1 Comments: 1286
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00z Best Track for 90E.

EP, 90, 2012051300, , BEST, 0, 102N, 1054W, 25, 1009, LO
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www.nola.com/rivercam
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Quoting WxGeekVA:
Seems to be refiring some convection, we'll see what happens though.




LOOP


it will be a record if Alberto comes out of 92L... the first storm of the season so far up north... and early too
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Rain just started coming in off the GulF.
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this made a new blog
Member Since: May 21, 2006 Posts: 5096 Comments: 116630
Really cool here near Dusk in NOLA as the Low cloud's spin in to the Low Center Nne of us now.

Looks mo August like.
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Quoting nigel20:
The 30 day SOI is now standing at +4.9


It keeps on the rising uptick now for almost two weeks.

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177. xcool
Although "Invest 92L" is merely a 100 mile wide gale center below the Azores (embedded in a closed cold 500MB low), there is a chance of an upgrade to depression or named storm status (Alberto) if the circulation and convection continues to maintain its integrity. The upper low should remain stationary, but is feeding moisture into a frontal structure over western/central Europe, resulting in locally heavy rainfall. Note the plume of tropical moisture flowing from the ITCZ northward from the Cameroons into Libya (cutting into the impressive Saharan heat ridge). The ITCZ in Equatorial Africa remains unusually well-defined and active with westward-progressing convective systems

by Larry Cosgrove
Member Since: September 26, 2009 Posts: 2 Comments: 15707
I like the Chrome a lot more than the Ol FireFox now Taz.

Been using it a year now maybe.

Good luck on your new Purchase.
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Quoting Patrap:
You on the cutting edge of the new stuff always Taz.

You should write a blog on that one.

I may get a tablet myself.



well its kind of hard tooo pick


with Samsung Galaxy Tab 2 you can run things like firefox and google chrome


i was all so planing on geting a ipad 2 but the olny thing is you cant run firefox and google chrome on a ipad

but the price for both i pad 2 and Samsung Galaxy Tab 2 is $399

so am going too get the Samsung Galaxy Tab 2 wish would all so be my 1st tablet and it can run firefox and google chrome
Member Since: May 21, 2006 Posts: 5096 Comments: 116630
The 30 day SOI is now standing at +4.9
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You on the cutting edge of the new stuff always Taz.

You should write a blog on that one.

I may get a tablet myself.
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am going too buy a Samsung Galaxy Tab 2 soon likey by the mid june
Member Since: May 21, 2006 Posts: 5096 Comments: 116630
A Wet exit for the Surface Low..

A Good Soaker here for all.



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Seems to be refiring some convection, we'll see what happens though.




LOOP
Member Since: September 3, 2011 Posts: 13 Comments: 3482
Quoting Tropicsweatherpr:
00z Best Track.

AL, 92, 2012051300, , BEST, 0, 346N, 307W, 45, 1009, LO

Why does it come out as soon as I leave the page -.-

That's ok, it won't happen again. I have a secret weapon.
Member Since: July 6, 2010 Posts: 113 Comments: 34481
Quoting pottery:
Good evening!
Mostly sunshine here today, but with haze and mist.
Looks to be setting up for a couple of drier days ahead.

About time.
Good evening Pott..How is " The Tree ".?...I hope things are going well down there. I have some fine red come soon..cant wait...:)
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Quoting Grothar:
Blob North of the Antilles.

If it was August, we would have to watch that one close...The GFS at 8.5 days has the system south of Cuba, but a little further east. It will probably flip flop back and forth between the gulf and the Bahamas for a few more days. There are some big changes with the strength of the troughs coming down. Notice the front with possible severe weather associated with it.
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00z Best Track.

AL, 92, 2012051300, , BEST, 0, 346N, 307W, 45, 1009, LO
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It looks like the nhc thinks that Alberto is more probable than Aletta base on their discussions.
Member Since: October 15, 2011 Posts: 0 Comments: 4545

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Dr. Masters co-founded wunderground in 1995. He flew with the NOAA Hurricane Hunters from 1986-1990. Co-blogging with him: Bob Henson, @bhensonweather

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