2016-2017 Southern Hemisphere tropical cyclone season

[Digital-TC-Chaser]

Shem about to break the shackles?

[Digital-TC-Chaser]

Tropical Cyclone Outlook
IDD10610
Tropical Cyclone Outlook for the Northern Region, including the Gulf of Carpentaria
Issued at 2:15 pm CST on Monday 6 February 2017
for the period until midnight CST Thursday 9 February 2017.
Existing Cyclones in the Northern Region:
Nil.
Potential Cyclones:

An active monsoon trough extends from the Kimberley, across the central Top End and into the Gulf of Carpentaria. A tropical low is likely to form over the Gulf of Carpentaria during Tuesday or Wednesday. Due to favourable conditions, the tropical low is expected to strengthen and there is a moderate chance of reaching tropical cyclone intensity on Thursday.

Likelihood of a tropical cyclone in the Northern Region on:
Tuesday:Very Low.
Wednesday:Very Low.
Thursday:Moderate.

NOTES: The likelihood is an estimate of the chance of each system being a tropical cyclone in the Region for each day.
Very Low:less than 5%Low:5% to 20%
Moderate:20 to 50%High:Over 50%
The area of coverage for this outlook is the Ocean area south of 9S, between 125E and 142E, including the Gulf of Carpentaria, but excluding the area around Timor (northwest of 11S 125E, 11S 128E, 9S 128E).
Further information on


Tropical Cyclone Outlook for the Western Region
Issued at 2:00 pm WST on Sunday 5 February 2017
for the period until midnight WST Wednesday 8 February 2017.
Existing Cyclones in the Western Region:
Nil.
Potential Cyclones:

The monsoon trough is active over the Browse Basin, Timor Sea, Arafura Sea and over waters north of the Pilbara. A weak low may form in the monsoon trough on Monday near the west Kimberley coast. The system will slowly develop while moving west or southwest away from the Kimberley during Tuesday. There is a Moderate risk of this system developing into a tropical cyclone during Wednesday as it moves over open waters north of the Pilbara coast.


Tropical Cyclone Outlook for Coral Sea
Issued at 2:30 pm EST on Monday 6 February 2017
for the period until midnight EST Thursday 9 February 2017.
Existing Cyclones in the Eastern Region:
Nil.
Potential Cyclones:

A monsoon burst is developing about northern parts of the Coral Sea. There is a slightly elevated risk of a tropical system developing in the Coral Sea mid to late week.

Likelihood of a tropical cyclone in the Eastern Region on:
Tuesday:Very low
Wednesday:Low
Thursday:Low

NOTES: The likelihood is an estimate of the chance of each system being a tropical cyclone in the Region for each day.
Very Low:less than 5%Low:5% to 20%
Moderate:20 to 50%High:Over 50%




-Fiji Meteorological Service
RSMC - Tropical Cyclone Centre


Tropical Disturbance Summary For area Equator to 25S, 160E to 120W
ISSUED FROM RSMC NADI Feb 052355 UTC.

TROPICAL DISTURBANCE 09F CENTRE [1004HPA] LOCATED NEAR 21.2S 179.7E
AT 052100UTC.POSITION POOR BASED ON HIMAWARI IR IMAGERY WITH
ANIMATION AND PERIPHERAL SURFACE OBSERVATIONS. TD09F SLOW MOVING.
CONVECTION DISPLACED TO THE EAST OF SUPPOSED LLCC. ORGANISATION
REMAINS POOR. SYSTEM LIES TO THE EAST OF AN UPPER TROUGH IN A HIGH
SHEARED ENVIRONMENT. SST IS AROUND 29 DEGREES CELCIUS. GLOBAL MODELS
HAVE PICKED THE SYSTEM AND MOVE IT SOUTHEASTWARDS WITH SLIGHT
INTENSIFICATION.

POTENTIAL FOR THIS SYSTEM TO DEVELOP INTO A TROPICAL CYCLONE IN THE
NEXT 24 TO 48 HOURS IS LOW.

NO OTHER SIGNIFICANT TROPICAL DISTURBANCE ANALYSED OR FORECAST IN THE
AREA.

[AJC3]

Looks to me like there's a pretty ridiculous vortex sheet roll-up going on within an unusually expansive SPCZ monsoon trough, which extends from the extreme eastern SIO basin through a large chunk of the SPAC.

[Calasanjy]

Looks to me like there's a pretty ridiculous vortex sheet roll-up going on within an unusually expansive SPCZ monsoon trough, which extends from the extreme eastern SIO basin through a large chunk of the SPAC.

Yes, there seems to be a large convective episode extending from the northwest coast of Australia to near and east of the International Dateline. I believe a strong Madden-Julian Oscillation (MJO) is in place, as well as the monsoon trough. I think there is a chance there could be a "cyclone outbreak" around Australia and the South Pacific within the coming week (I define an outbreak as 3 or more active cyclones). The models I have seen over the past few days seem to suggest that at least 2-3 cyclones may soon form. Nothing like an outbreak to cut into the deficit. However, only time will tell, as numerous "model storms" have failed to materialize this season.

[1900hurricane]

The current setup actually reminds me of the one for the WPac during much of August 2016. We're currently seeing an active but rather poleward monsoon trough setup. Good for incipient disturbances, but they're quickly running into hostile conditions once they try to gain sovereignty and develop into tropical cyclones.

[Digital-TC-Chaser]

Looks to me like there's a pretty ridiculous vortex sheet roll-up going on within an unusually expansive SPCZ monsoon trough, which extends from the extreme eastern SIO basin through a large chunk of the SPAC.

Is mega in length
http://www.bom.gov.au/fwo/IDY65100.pdf

[Digital-TC-Chaser]

Tropical Disturbance Summary For area Equator to 25S, 160E to 120W
ISSUED FROM RSMC NADI Feb 081005 UTC.

TROPICAL DISTURBANCE TD09F CENTRE [1000HPA] LOCATED NEAR 20.0S 179.3E
AT 080900UTC.POSITION POOR BASED ON HIMAWARI IR IMAGERY WITH
ANIMATION AND PERIPHERAL SURFACE OBSERVATIONS. TD09F MOVING EAST AT
05 KNOTS.
CONVECTION DISPLACED TO THE EAST OF SUPPOSED LLCC. ORGANISATION
REMAINS POOR. SYSTEM LIES UNDER AN UPPER DIFLUENT REGION IN A HIGH
SHEARED ENVIRONMENT. SST IS AROUND 29 DEGREES CELCIUS.

GLOBAL MODELS ARE MOVING TD09F EAST-SOUTHEAST WITH SLIGHT
INTENSIFICATION.

POTENTIAL FOR THIS SYSTEM TO DEVELOP INTO A TROPICAL CYCLONE IN THE
NEXT 24 TO 48 HOURS IS LOW.

*********************************************************************
***************

TROPICAL DISTURBANCE TD10F CENTRE [996HPA] LOCATED NEAR 21.3S 166.0E
AT 080900UTC. POSITION POOR BASED ON HIMAWARI IR IMAGERY WITH
ANIMATION AND PERIPHERAL SURFACE OBSERVATIONS. TD10F MOVING
SOUTHEAST AT 13 KNOTS.
DEEP CONVECTION HAS INCREASED AND ORGANISATION HAS IMPROVED SLIGHTLY
IN THE PAST 24 HOURS. SYSTEM LIES UNDER A ANTICYCLONIC CIRCULATION IN
A LOW SHEARED ENVIRONMENT. CYCLONIC CIRCULATION EXTENDS UPTO 500HPA.
SST IS AROUND 30 DEGREES CELCIUS.

GLOBAL MODELS HAVE PICKED THE SYSTEM AND MOVE IT SOUTHEAST WITH SOME
INTENSIFICATION.

POTENTIAL FOR THIS SYSTEM TO DEVELOP INTO A TROPICAL CYCLONE IN THE
NEXT 24 TO 48 HOURS IS LOW TO MODERATE.




http://www.ssd.noaa.gov/PS/TROP/Basin_SouthPac.html


SPECIAL WEATHER BULLETIN NUMBER THIRTY SIX FOR HEAVY RAIN ISSUED FROM RSMC NADI AT 11AM ON THURSDAY THE 9TH OF FEBRUARY, 2017.

HEAVY RAIN WARNING

A HEAVY RAIN WARNING REMAINS IN FORCE FOR LAU GROUP.
A HEAVY RAIN ALERT REMAINS IN FORCE FOR THE REST OF FIJI.

SITUATION:
TROPICAL DISTURBANCE 09F CENTRE [1000HPA] WAS ANALYSED NEAR 19.3S 179.0W OR ABOUT 130KM EAST OF MATUKU AND ABOUT 300KM EAST-SOUTHEAST OF SUVA AT 6AM TODAY.
TD09F IS MOVING EAST AT APPROXIMATELY 12KM/HR. ASSOCIATED TROUGH OF LOW PRESSURE WITH CLOUD AND RAIN AFFECTS THE NORTHERN AND EASTERN PARTS
OF THE GROUP. MEANWHILE, ANOTHER ACTIVE TROUGH OF LOW PRESSURE TO THE FAR WEST OF FIJI IS ANTICIPATED TO MOVE EAST AND AFFECT THE COUNTRY FROM FRIDAY AFTERNOON.

FORECAST FOR THE WHOLE OF FIJI GROUP.
TILL MIDNIGHT THURSDAY FOR LAU GROUP:
PERIODS OF RAIN, HEAVY AT TIMES AND SQUALLY THUNDERSTORMS, EASING TO OCCASIONAL SHOWERS AND FEW THUNDERSTORMS WITH HEAVY FALLS FROM THIS AFTERNOON.
FOR THE REST OF FIJI:
OCCASIONAL SHOWERS AND FEW THUNDERSTORMS WITH HEAVY FALLS.
FOR FRIDAY: SHOWERS INCREASING TO RAIN, BECOMING FREQUENT AND HEAVY AT TIMES WITH SQUALLY THUNDERSTORMS FROM AFTERNOON OVER MOST PLACES.

24 HOURS RAINFALL SINCE 4AM YESTERDAY(08/02) OVER SOME STATIONS AROUND FIJI;-

STATIONS RAINFALL(mm)
TAVUA - 238.0
YAQARA - 179.0
BA - 131.2
NADARIVATU - 125.0
RAKIRAKI - 118.5
LAKEBA - 81.5
UDU POINT - 62.4

LOCALISED HEAVY RAIN MAY LEAD TO FLASH FLOODING.

FOR CURRENT FLOOD WARNINGS AND ALERTS REFER TO http://www.met.gov.fj/aifs_prods/20016.txt

THE NEXT SPECIAL WEATHER BULLETIN ON HEAVY RAIN WILL BE ISSUED AT 2PM TODAY OR EARLIER.


EC/GFS MODELS with all the bells and whistles.
https://www.windytv.com/?-21.085,164.377,5

https://www.ventusky.com/?p=15.1;125.8; ... =0QEQYp_5B
ICON /GFS/CMC same as above,go into WEATHER MAP SETTINGS. Show values in grid. (tick)

http://www.ann-geophys.net/27/2523/2009 ... 3-2009.pdf

[1900hurricane]

I'm doubting we're going to see any type of significant tropical development from it, but the activity in the SPCZ is pretty cool to look at right now.

[Digital-TC-Chaser]

http://www.tropicaltidbits.com/analysis ... ypos=880.8
00z... 186Hrs out to the end of the run looping strong TC,long way way out.

[1900hurricane]

For those accustomed to viewing tropical cyclones in the Northern Hemisphere (like I am), here is a flipped version of the SPCZ right now. Awesome.

[Calasanjy]

Just an amateur opinion, but here are my thoughts on potential tropical cyclones for the next week:

05P/Alfred - Gulf of Carpentaria - 80% chance of development. Guess for maximum intensity - 50 knots. Quick development and landfall in Northern Australia, preventing further intensification. However, it may eventually reemerge over water off Western Australia but I do not feel comfortable providing a potential for redevelopment or maximum intensity estimate for such an eventuality.

06S/Dineo - Mozambique Channel - 50% chance of development. Guess for maximum intensity - 60 knots. Landfall in Mozambique, preventing further intensification.

An additional TC has a 50% chance of development in the Coral Sea the following week (between February 16 and 23). This is the system that was mentioned previously as being indicated by the models, but I do not trust models to be more than half accurate more than a few days in advance. I am not sure about other areas in the Southern Hemisphere for that timeframe.

[Digital-TC-Chaser]

Wonders with the slow season thus far if maybe it may end similar to the Wpac 2016 back loaded.

[1900hurricane]

The SPCZ (which is essentially semi-permanent reverse-oriented monsoon trough) looks like it has begun monsoon trough breakdown. Two good-looking invests have been declared as a result. 96P is to the west and 97P is to the east.



*EDIT: I don't know east from west.

[Digital-TC-Chaser]

positions of invests as quoted above.

[Steve820]

I really do hope and predict that at least a couple of these invests will eventually become named storms. It would be a real pity if they didn't. The SPac is in extreme desperate need of a named storm, as it has not seen a SINGLE named storm yet this season. The Australian region has been very slow too, with only Yvette forming there AFAIK. What was going on here?! The SHem has been so slow that it must be a record. Hopefully, with these invests, the absolutely dead SHem finally gets going.

[Digital-TC-Chaser]

[dexterlabio]

For those accustomed to viewing tropical cyclones in the Northern Hemisphere (like I am), here is a flipped version of the SPCZ right now. Awesome.

Ahhh...very reminiscent to the reverse-oriented monsoon outbreak in WPAC last August 2016. I wonder if there will be at least one potent system to develop out of this parade, like Cat4 Lionrock.

[Calasanjy]

Seasons like this make me wish there were a viable "tropical cyclone simulation" available, similar to a game like SimCity but simulating tropical weather, so I could at least imagine that there are storms to track. If anyone knows of such a thing, please let me know, otherwise I may try to develop one.

Still waiting for additional TCs even though we are still in the heart of the season...

[Digital-TC-Chaser]

Usually these out this wide bora bora tahiti pop-up in elnino.



ABPW10 PGTW 150600
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/SIGNIFICANT TROPICAL WEATHER ADVISORY FOR THE WESTERN AND
SOUTH PACIFIC OCEANS/150600Z-160600ZFEB2017//
RMKS/
1. WESTERN NORTH PACIFIC AREA (180 TO MALAY PENINSULA):
A. TROPICAL CYCLONE SUMMARY: NONE.
B. TROPICAL DISTURBANCE SUMMARY: NONE.
2. SOUTH PACIFIC AREA (WEST COAST OF SOUTH AMERICA TO 135 EAST):
A. TROPICAL CYCLONE SUMMARY: NONE.
B. TROPICAL DISTURBANCE SUMMARY:
(1) AN AREA OF CONVECTION (INVEST 90P) HAS PERSISTED NEAR
13.4S 148.6W, APPROXIMATELY 260 NM NORTHEAST OF BORA BORA. ANIMATED
MULTISPECTRAL SATELLITE IMAGERY AND A 150423Z SSMIS 91GHZ MICROWAVE
IMAGE SHOWS SCATTERED CONVECTION ALONG THE OUTER EDGE, PRIMARILY ON
THE NORTHEAST SIDE, OF A LOW LEVEL CIRCULATION CENTER (LLCC). A
141834Z METOP-B ASCAT PARTIAL PASS SHOWS AN ELONGATED LLCC WITH 30
KNOT WINDS TO THE EAST OF THE DISTURBANCE, BUT THE WINDS DO NOT
APPEAR TO BE WRAPPING INTO THE CIRCULATION AT THIS TIME. THE
DISTURBANCE IS CURRENTLY LOCATED IN A MIXED ENVIRONMENT, WITH WARM
SEA SURFACE TEMPERATURES (AROUND 28 C), LOW VERTICAL WIND SHEAR (5-
10 KNOTS), AND MODERATE EQUATORWARD OUTFLOW. HOWEVER AN UPPER LEVEL
TROUGH POSITIONED JUST TO THE SOUTH IS HINDERING DEVELOPMENT. GLOBAL
MODELS SHOW SOME INTENSIFICATION OVER THE NEXT SEVERAL DAYS,
PRIMARILY GRADIENT INDUCED AND CONFINED TO THE EASTERN PERIPHERY.
MODELS ALSO INDICATE THE DISTURBANCE WILL TRACK TOWARDS
THE SOUTHEAST AS A SUBTROPICAL SYSTEM. MAXIMUM SUSTAINED SURFACE
WINDS ARE ESTIMATED AT 10 TO 15 KNOTS. MINIMUM SEA LEVEL PRESSURE IS
ESTIMATED TO BE NEAR 1010 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A
SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS LOW.
(2) NO OTHER SUSPECT AREAS.//

[1900hurricane]

This season seems determined to troll the BOM. Check out this microwave pass of their classified Tropical Low making landfall.



JTWC has been slow to the punch too, since they still have it tagged as Invest 91P.