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Double Trouble: twin tropical cyclones spin up in the Indian Ocean

By: Dr. Jeff Masters, 3:27 PM GMT on May 10, 2013

There's double trouble in the Indian Ocean today, with a pair of counter-rotating tropical cyclones spinning away on either side of the Equator. In the Southern Hemisphere, we have Tropical Cyclone Jamala, a tropical storm with 45 mph winds that is headed southwards at 3 mph. Jamala is expected to intensify into a Category 1 storm over the weekend, but is not a threat to any land areas. In the Northern Hemisphere, it's Tropical Cyclone 01B, a tropical storm with 40 mph winds that is dumping heavy rains over western Sumatra. This storm much larger and far more dangerous than its Southern Hemisphere twin brother. Cyclone 01B is under high wind shear of 20 - 30 knots, which is keeping the system disorganized, with the heaviest thunderstorms displaced from the center of rotation. However, Cyclone 01B is expected to move generally northwestwards over the next few days through the Bay of Bengal, where wind shear is lower and ocean temperatures are an exceptionally warm 31°C (88°F). This is about 1°C warmer than average for this time of year. The official forecast brings the storm to Category 1 strength before landfall occurs in Myanmar just south of the border with Bangladesh early next week. Comparative model forecasts of Cyclone 01B from the GFS, ECMWF, UKMET, GEM, NAVGEM, and FIM models show poor agreement on the intensity of Cyclone 01B, though, and it is possible that wind shear will keep the storm disorganized until landfall, with heavy rain being the main threat.


Figure 1. Double trouble: Tropical Cyclone Jamala (lower) and Tropical Cyclone 01B (upper storm) spin on opposite sides of the Equator in this infrared satellite image taken at 12 UTC (7 am EDT) Friday May 10, 2012. Image credit: University of Wisconsin CIMSS.

Twin tropical cyclones: how unusual?
Twin cyclones forming on either side of the Equator are surprisingly common in the Indian Ocean. They tend to spin up in May and November--the months immediately preceding and following the annual monsoon (the monsoon dominates the circulation patterns during June - October, making tropical cyclones rare in the Northern Indian Ocean during those months.) The most recent occurrence of twin developments happened unusually late: the end of December 2011, when Tropical Cyclones Thane and Benilde developed. Both storms became mature hurricanes, with Thane hitting the southeast coast of India on December 30, making it the second latest landfalling cyclone in India (thanks go to Meteo-France's Philippe Caroff of RSMC La Reunion for this info.)

Usually, the twin storms spin up when the active phase of the Madden Julian Oscillation (MJO) is present. The MJO is a pattern of increased thunderstorm activity near the Equator that moves around the globe in 30 - 60 days. The area of increased thunderstorms associated with the MJO currently straddles the Equator in the Indian Ocean, and is helping boost thunderstorm activity in both Cyclone 01B and Tropical Cyclone Jamala. The strong MJO pulse coincides with something called a convectively coupled atmospheric Kelvin wave (CCKW), which is helping increase thunderstorm activity as well. The tutorial on Equatorial Waves in the COMET program's excellent Introduction to Tropical Meteorology, (free, but registration required) gives several examples of twin tropical cyclones forming on either side of the Equator. One of these cases occurred in November 2007, when the notorious Tropical Cyclone Sidr formed in the North Indian Ocean at the same time that Tropical Cyclone Lee-Ariel formed on the other side of the Equator. Sidr struck Bangladesh as a Category 4 storm, killing up to 10,000 people. Dr. Michael Ventrice of wsi.com gave me these examples of other twin Indian Ocean tropical cyclones that formed between 1990 - 2009:

1. mid Oct 1992
1. early November 1993 
2. late April 1994
3. mid Nov 1995
4. late April/early May 1995 
5. late October 1995
6. mid March 2000
7. early May 2002 (*Great Example, two sets of twins*) 
8. early Nov 2002
9. mid Dec 2002
10. early Dec 2003
11. early July 2004 
12. late April 2008
13. mid Oct 2008
14. mid Nov 2008
15. early Nov. 2009 

These twin cyclone events tend to  most commonly occur during strong MJO events over the Indian Ocean (strong equatorial lower tropospheric westerly winds), but it's not the only time that they can occur. To look at these years with MJO and Kelvin wave type filtered anomalies overlaid (contours), please visit http://www.atmos.albany.edu/student/ventrice/ncep/5S-5N/. Here, blue shaded TCs represent the tropical depression category forming south of the equator, whereas red TC symbolizes depressions that have formed north of the equator. 

It's worth mentioning that the active pulse of the Madden Julian Oscillation is expected to reach the Western Caribbean sometime May 22 - 26, and there will be a heightened chance of an early-season tropical storm forming in the Eastern Pacific and Western Caribbean during that time period.


Figure 2. The most spectacular case of twin cyclones in the Indian Ocean: "twin twins" on May 9, 2002. A strong MJO event superimposed with a strong convectively coupled atmospheric Kelvin wave passed the Indian Ocean and two sets of twins developed, the first over 60E on May 1-3, and the second pair of twins over 90E May 8-10. The eastern pair of twins are Tropical Cyclone Errol (Southern Hemisphere) and Tropical Cyclone 02B (Northern Hemisphere.) The western pair had quite a significant impact, with Tropical Cyclone Kesiny in the Southern Hemisphere making landfall in northern Madagascar as a hurricane, which was the first occurrence of a hurricane making landfall in the month of May in the Southwest Indian Ocean in at least 40 years (though Kesiny was followed the next year by Tropical Cyclone Manou, which hit the east coast of Madagascar at an even higher intensity.) Kesiny affected half a million people in Madagascar and caused numerous fatalities (at least 33), with people being drowned due to severe flooding in the aftermath of the TC-related rain event (Toamasina the major harbour of the country and main city of the east coast of the island received 891 mm (35.08") of rainfall in 3 days--although being quite far to the south from the landfalling point). At the same time, Tropical Cyclone 01A finished its life on the arid land of the Arabian Peninsula, also generating a severe rain event (unprecedented in at least 30 years), which caused devastation in the Dhofar region of western Oman. An observing station reported 251 mm (9.88") of rainfall (the equivalent of 4 to 5 years of average rainfall for this arid region). At least 9 fatalities were attributed to this unusual storm and rain event. Thanks go to Meteo-France's Philippe Caroff of RSMC La Reunion for this info and image.

Resources
Comparative model forecasts of Cyclone 01B from the GFS, ECMWF, UKMET, GEM, NAVGEM, and FIM models.

India Meteorological Department's tropical cyclone page


Tutorial on Equatorial Waves in the COMET program's Introduction to Tropical Meteorology, plus their case exercise built around the May 2002 "twin twins" case, for use in a tropical synoptic course.

Equatorial Rossby Waves and Twin Tropical Cyclogenesis

Dynamical Aspects of Twin Tropical Cyclones Associated with the Madden-Julian Oscillation

Shen, B.-W., W.-K. Tao, Y.-L. Lin, and A. Laing, 2012: Genesis of twin tropical cyclones as revealed by a global mesoscale model: The role of mixed Rossby-gravity waves. J. Geophys. Res., 117, D13114, doi:10.1029/2012JD017450


Have a great weekend, everyone!

Jeff Masters

Hurricane

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.

Reader Comments

for today in florida it looks like an inland and east coast event if it happens..they do say there is the possibility of severe storms.
Quoting pcola57:
Quoting Dakster:
Thanks Largo. I was going to replace some house siding today... Looks like that might have to wait a bit.
yes it might be wise to wait till this front clears out of here..dont want the insulation getting wet huh.
well i guess i'd better walk the dogs in the park before the rains get here..see ya all later..stay safe and alert today.
Quoting LargoFl:
yes it might be wise to wait till this front clears out of here..dont want the insulation getting wet huh.


Or the house flooding... The joys of a wood frame house in Florida.
GFS phase diagrams say the disturbance made huge progress in acquiring a warm core. Last night the system was well within the asymmetric cold-core phase.

Quoting MississippiWx:


I'm thinking the same thing. It's awful persistent and shear doesn't seem to be quite as bad as yesterday. Seeing that it is forming from an upper low from the top down, the shear isn't quite as bad over it. The convection has certainly consolidated near the center this morning.



just an ull there dont see much chance at the surface.

From Google News..

USA Today news release..

Spacewalkers to tackle leak at space station

CAPE CANAVERAL, Fla. (AP) — Two astronauts took a hastily planned spacewalk Saturday to find and, possibly, fix a serious leak at the International Space Station.

Flakes of frozen ammonia coolant were spotted Thursday drifting from the long frame that holds the solar panels on the left side. Less than 48 hours later, Thomas Marshburn and Christopher Cassidy emerged from the orbiting lab to hunt for the leak. They were prepared to replace a pump, if necessary.

NASA said the leak, while significant, poses no safety threat. But managers wanted to deal with the trouble now, while it's fresh and before Marshburn returns to Earth in just a few days.

The space agency has never staged such a fast, impromptu spacewalk for a station crew. Even during the shuttle days, unplanned spacewalks were rare.

At the beginning of the spacewalk, neither astronaut spotted any flakes of ammonia or anything else amiss as they reached the spot in question and began an inspection.

"I see nothing off-nominal," Cassidy said. He noted some smudges, but nothing more
The astronauts needed to take pictures of the equipment, but the connection to the camera's flash was not working and Marshburn had to wait until the space station reached the daylight side of Earth.

Flight controllers in Houston worked furiously to get ready for Saturday's operation, completing all the required preparation in under 48 hours. The astronauts trained for just such an emergency scenario before they rocketed into orbit; the repair job is among NASA's so-called Big 12.

This area on the space station is prone to leaks. The ammonia coursing through the plumbing is used to cool the space station's electronic equipment. There are eight of these power channels, and all seven others were operating normally. As a result, life for the six space station residents was pretty much unaffected, aside from the drama unfolding Saturday 255 miles above the planet.

NASA's space station program manager Mike Suffredini said it's a mystery as to why the leak erupted. One possibility is a micrometeorite strike. If there is nothing to suggest that the old pump is at fault, then the spacewalkers expect to leave it in place and go back inside as flight controllers figure out the next step.

Marshburn has been on the space station since December and is set to return to Earth late Monday. Cassidy is a new arrival, on board for just 1½ months.

"Suddenly very busy," Marshburn said via Twitter on Friday.

By coincidence, the two performed a spacewalk at this troublesome spot before, during a shuttle visit in 2009.
Quoting Dakster:
Emergency ISS Spacewalk.

They have a leak...

You can watch it live... which I am doing right now. (CNN, but I am sure NASA has it as well)


Got it live on NASA TV HD at my house. I remember back in 2007 they were doing an EVA when they flew over a Category 4 Hurricane Dean in the Central Caribbean. Still stunning to think of to this day.
Quoting pcola57:


****

Gro..
How come your links are so much better than mine?
What you got that I ain't got??..Lol.. :)


Just think of what I've already lost. :)
If I'm seeing this right, another SSW (Sudden Stratospheric Warming) event is either happening or just concluded. If so, what effect on the tropics (if any) will such an event have happening this close to summer and the start of the hurricane season, given the havoc they wreak on hemispheric weather patterns?

SSW


The GFS shows the system currently at the border between symmetric-cold core and symmetric warm-core.

Quoting pcola57:
From Google News..

USA Today news release..

Spacewalkers to tackle leak at space station

CAPE CANAVERAL, Fla. (AP) — Two astronauts took a hastily planned spacewalk Saturday to find and, possibly, fix a serious leak at the International Space Station.

Flakes of frozen ammonia coolant were spotted Thursday drifting from the long frame that holds the solar panels on the left side. Less than 48 hours later, Thomas Marshburn and Christopher Cassidy emerged from the orbiting lab to hunt for the leak. They were prepared to replace a pump, if necessary.

NASA said the leak, while significant, poses no safety threat. But managers wanted to deal with the trouble now, while it's fresh and before Marshburn returns to Earth in just a few days.

The space agency has never staged such a fast, impromptu spacewalk for a station crew. Even during the shuttle days, unplanned spacewalks were rare.

At the beginning of the spacewalk, neither astronaut spotted any flakes of ammonia or anything else amiss as they reached the spot in question and began an inspection.

"I see nothing off-nominal," Cassidy said. He noted some smudges, but nothing more
The astronauts needed to take pictures of the equipment, but the connection to the camera's flash was not working and Marshburn had to wait until the space station reached the daylight side of Earth.

Flight controllers in Houston worked furiously to get ready for Saturday's operation, completing all the required preparation in under 48 hours. The astronauts trained for just such an emergency scenario before they rocketed into orbit; the repair job is among NASA's so-called Big 12.

This area on the space station is prone to leaks. The ammonia coursing through the plumbing is used to cool the space station's electronic equipment. There are eight of these power channels, and all seven others were operating normally. As a result, life for the six space station residents was pretty much unaffected, aside from the drama unfolding Saturday 255 miles above the planet.

NASA's space station program manager Mike Suffredini said it's a mystery as to why the leak erupted. One possibility is a micrometeorite strike. If there is nothing to suggest that the old pump is at fault, then the spacewalkers expect to leave it in place and go back inside as flight controllers figure out the next step.

Marshburn has been on the space station since December and is set to return to Earth late Monday. Cassidy is a new arrival, on board for just 1½ months.

"Suddenly very busy," Marshburn said via Twitter on Friday.

By coincidence, the two performed a spacewalk at this troublesome spot before, during a shuttle visit in 2009.


;>)
Lt. Cmdr. Geordi La Forge:"Coolant leak! Bridge we got a coolant leak in the engine core! I can't shut it down! I estimate two minutes to a warp core breach!"
nice spin to it now.
Quoting docrod:


;>)
Lt. Cmdr. Geordi La Forge:"Coolant leak! Bridge we got a coolant leak in the engine core! I can't shut it down! I estimate two minutes to a warp core breach!"


Lol..
Thats a good one doc.. :)
Quoting Neapolitan:
If I'm seeing this right, another SSW (Sudden Stratospheric Warming) event is either happening or just concluded. If so, what effect on the tropics (if any) will such an event have happening this close to summer and the start of the hurricane season, given the havoc they wreak on hemispheric weather patterns?

SSW




Quoting pcola57:
Thanks Dr. Masters for the updated blog..
Seeing those "twins" in the Indian Ocean is cool..
But that brings up a new question as well..
Why don't we see this in our basin ?
Could we expect to see this more often in a warming world ?
Thanks again..




I haven't seen that Nea..
I included my post #41 from the current blog..
I thought my questions were relevant..
Just as the one you posed..
Thanks for posting..
Quoting Grothar:


interesting twist out there. not moving west however.
Quoting Grothar:


Will it go 'round in circles?
Will it fly high up in the sky?

Mr Billy Preston.. :)
What do you say Grothar, is it blob worthy? :)
Quoting pcola57:


Will it go 'round in circles?
Will it fly high up in the sky?

Mr Billy Presto.. :)


YES - I posted a FRO ref last week. 8>)
I did not like the song when it first came out. Mellowed since.
Quoting docrod:


interesting twist out there. not moving west however.

It should stay stationary while pinned between open Atlantic surface ridge to the northeast and front about push off of the US shore...then eventually get absorbed by that front.
Quoting NCHurricane2009:

It should stay stationary while pinned between open Atlantic surface ridge to the northeast and front about push off of the US shore...then eventually get absorbed by that front.



that front is forecast to push through the FL Keys by Wed - may stall - I'm in the middle Keys
Quoting CybrTeddy:
What do you say Grothar, is it blob worthy? :)


Not yet. Just a swirl.
Quoting hurricanes2018:
nice spin to it now.


Link to NW Atlc Satellite...

Most of that spin seems to be with that upper-level low that triggered this system. You can highlight the upper-wind direction by clicking on the HDW-H checkbox in the above link....

Link to Surface Map

At the surface this thing is still an open trough of low pressure...no closed surface spin right now...
527. SLU
Pre-1st August Named Storm Days – South of 23.5°N, East of 75°W is usually an indicator of the very busy Cape Verde season. For example, the seven years with the most named storm days in the deep tropics in June and July (since 1949) are 1966, 1969, 1995, 1996, 1998, 2005 and 2008. All seven of these seasons were very active. When storms form in the deep tropics in the early part of the hurricane season, it indicates that conditions are already very favourable for TC development. In general, the start of the hurricane season is restricted by thermodynamics (warm SSTs, unstable lapse rates), and therefore deep tropical activity early in the hurricane season implies that the thermodynamics are already quite favourable for TC development.

Even if this disturbance north of Puerto Rico near 23°N and 66°W doesn't develop further, the mere fact that it could get so well defined south of 23.5°N, East of 75°W in mid-May is a huge sign of a very active season on the way.

Quoting SLU:
Pre-1st August Named Storm Days – South of 23.5°N, East of 75°W is usually an indicator of the very busy Cape Verde season. For example, the seven years with the most named storm days in the deep tropics in June and July (since 1949) are 1966, 1969, 1995, 1996, 1998, 2005 and 2008. All seven of these seasons were very active. When storms form in the deep tropics in the early part of the hurricane season, it indicates that conditions are already very favourable for TC development. In general, the start of the hurricane season is restricted by thermodynamics (warm SSTs, unstable lapse rates), and therefore deep tropical activity early in the hurricane season implies that the thermodynamics are already quite favourable for TC development.

Even if this disturbance north of Puerto Rico near 23°N and 66°W doesn't develop further, the mere fact that it could get so well defined south of 23.5°N, East of 75°W in mid-May is a huge sign of a very active season on the way.


What a recap! You sure have a way with words. This is a nice write up. Thanks for posting this.
Mahasen up to 50kts. Sadly Bangladesh is now in the bullseye.

Quoting Grothar:


Just think of what I've already lost. :)


youth.

;)
C'mon NHC give us an invest.Do it for the fans :) (and no I am not downing the NHC).
TAFB adds on 12z surface analysis a weak surface low north of PR.



533. SLU
Quoting washingtonian115:
C'mon NHC give us an invest.Do it for the fans :) (and no I am not downing the NHC).


This is good enough to at least be declared our 1st invest of the year.

partial shot of spinner

The system north of Puerto Rico has surprisingly completed its "top down" process and now has a weak surface low with some shallow convection developing near the newly formed low. Shear really isn't a problem since the system is basically a hybrid right now. With that being said, sea surface temperatures are marginal with readings AOA 77-79 Fahrenheit and very decent theta-e in the region which should support convection.

Persistence has definitely been this systems greatest ally and I imagine if this develops any more than it already has, that we will see a STWO within the next 12 hours. Although, I don't really see any reason why this should persist for any longer than 18-24 hours due to the upper level setup and with that being said I also very highly doubt that anything more than a short lived invest comes from this.

http://i300.photobucket.com/albums/nn39/Stormchas er20079/2013%20Hurricane%20Season/ScreenHunter_20M ay111131.png

Hey Everyone..

Beautiful saturday here in eastern NC..looks like something is brewing on the horizon..looks like the GFS operational has slowed down again in timing of the long range storm

06z GFS Ensembles however hasnt..why is that?






Quoting Tropicsweatherpr:
TAFB adds on 12z surface analysis a weak surface low north of PR.





O_o ....does anyone have a quickscat of the area to see if a surface rotation is closing off?
There is another little area of interest in the Atlantic..that flock of gulls off Africa..



Pretty fresh ASCAT of that..

Declaring it an invest wouldn't be a bad idea right now. It's not expecte to last long but, it's interesting nonetheless.
Quoting NCHurricane2009:


O_o ....does anyone have a quickscat of the area to see if a surface rotation is closing off?

Quikscat died a long time ago. Windsat looks dysfunctional. I'm waiting with abated breathe on ASCAT. If that doesn't catch it, OSCAT should follow a few hours later.
Quoting Skyepony:

Quikscat died a long time ago. Windsat looks dysfunctional. I'm waiting with abated breathe on ASCAT. If that doesn't catch it, OSCAT should follow a few hours later.


Is there an OSCAT of Mahasen?
Quoting Grothar:


Not yet. Just a swirl.

Just a Swirl ?
Nothing to worry about ??

Huh! I've been undone by a swirl several times, particularly a swirl of petticoats.
I'm sure you remember.
But some of the others around here might need to google that to find out what it is.....

Aaahhhh....
Quoting NCHurricane2009:


O_o ....does anyone have a quickscat of the area to see if a surface rotation is closing off?


QUICKSCAT has been dead for over 3 years.
Quoting Skyepony:
There is another little area of interest in the Atlantic..that flock of gulls off Africa..



Pretty fresh ASCAT of that..



Are you sure those aren't the Cape Verde Islands?? :)
Crossing fingers for a special two.
Looks like the GFS has something spinning up wayyy down the line, and if I'm correct, no other models are showing this. Still interesting

Quoting washingtonian115:
Crossing fingers for a special two.


Or at least 90L.
Quoting cg2916:
Looks like the GFS has something spinning up wayyy down the line, and if I'm correct, no other models are showing this.


GFS has been quite consistent in showing this, and every run the past couple days has shown a tropical storm developing in the Caribbean.
India Meteorological Department
Tropical Cyclone Advisory #8
CYCLONIC STORM MAHASEN (BOB01-2013)
17:30 PM IST May 11 2013
==========================================

At 12:00 PM UTC, The cyclonic storm Mahasen over southeast Bay of Bengal moved slighly northwestward and now lays near 8.0N 89.5E, about 400 km southwest of Car Nicobar, 900 km east southeast of Trincomalee, Sri Lanka, 1150 km southeast of Chennai, India, and 1600 km south southwest of Chittagong, Bangladesh.

The system would intensify further into a severe cyclonic storm during the next 24 hours. It would move initially northwestwards during the next 36 hours and thereafter northeastwards towards Bangladesh-Myanmar coast.

According to satellite imagery, the Dvorak intensity of Cyclonic Storm Mahasen is T2.5. It is a curved band pattern. Intense to very intense convection seen over south Bay of Bengal, adjoining Indian Ocean between 3.0N and 12.5N and 82.0E and 96.0E, extreme northern Sumatra, Nicobar Islands, and southwest Andaman Sea. The lowest cloud top temperature due to convection is about -85C.

3 minute sustained winds near the center is 40 knots with gusts of 50 knots. The central pressure of the system is 996 hPa. The state of the sea is high around the center of the system.

The upper tropospheric ridge runs along 12.0N and is providing poleward outflow in association with the anticyclonic circulation over southern Andaman Sea. Hence, divergence is favorable for intensification. The low level convergence along with low level relative vorticity has increased further in the past 12 hours. The sea surface temperature is about 30C and ocean thermal energy is about 100 kj/cm2. The vertical wind shear of horizontal wind is about 10-20 knots (HIGH) in the northwest sector. It has decreased around the system and is about 10-20 knots (MODERATE). The MJO now lies over phase 3 with amplitude greater than 2. It is favorable for intensification.

Forecast and Intensity
======================
12 HRS: 09.6N 88.1E - 45 knots (Cyclonic Storm)
24 HRS: 11.0N 86.7E - 55 knots (Severe Cyclonic Storm)
48 HRS: 13.5N 86.2E - 60 knots (Severe Cyclonic Storm)
72 HRS: 16.5N 87.5E - 60 knots (Severe Cyclonic Storm)
Quoting dfwstormwatch:

GFS has been quite consistent in showing this, and every run the past couple days has shown a tropical storm developing in the Caribbean.


Yes, although as Levi32 pointed out, even though the GFS has been consistent in showing a TS in the Caribbean, it keeps pushing back the date.
Quoting cg2916:


Yes, although as Levi32 pointed out, even though the GFS has been consistent in showing a TS in the Caribbean, it keeps pushing back the date.

Hmm, seems to me it has been moving up the timeline quite nicely since Wednesday.
Quoting hurricane23:


just an ull there dont see much chance at the surface.



Highly disagree that there is nothing at the surface.



I realize that this is 850mb, but there was hardly anything showing at 850 yesterday. This is an upper low that has gone from top down to the surface thanks to persistent convection.
Quoting cg2916:
Looks like the GFS has something spinning up wayyy down the line, and if I'm correct, no other models are showing this. Still interesting

you should ignore 360 hours out,its way too far in the future
Quoting TropicalAnalystwx13:
Declaring it an invest wouldn't be a bad idea right now. It's not expecte to last long but, it's interesting nonetheless.


The GFS had this area of precip persisting for another 48-60 hours on the 00z run last night. It will be around long enough. The problem is that none of the models are picking up on any area of low pressure.
This reminds me of Beryl from last year.
Quoting LargoFl:
you should ignore 360 hours out,its way too far in the future

It shows it developing around 288 hours, and has been consistent in the past 10 or so runs by showing it.
Quoting MississippiWx:


Highly disagree that there is nothing at the surface.



I realize that this is 850mb, but there was hardly anything showing at 850 yesterday. This is an upper low that has gone from top down to the surface thanks to persistent convection.


OK ok there appears to be something at the surface :0). From what i can tell It seems vertically stacked with the ull. Worth watching i guess
noaa doesnt see anything tropical at all.............
JeffMasters has created a new entry.
12z GFS is running..that low looks to stick around

27 hours


39 hours


45 hours


63 hours


75 hours