Gedday,

Just curious concerning what Qld/NT offices are thinking concerning any
TC-development potential for  the mass of  convection that has existed
over the past day in the northern Gulf?  From  the charts I can see there
is no circulation at all, but there is a fair  amount of cyclonic
(-partialU/partial-y) vorticity associated with the  equatorward side of
an easterly max; and there is a large scale anticylone  over it at upper
levels..... Any thoughts?

Charts 8 April:

  
                Satellite image                                                                                        850hPa analysis

  
                            900 hPa vorticity                                                                                        250 hPa

John McB

Jeff Callaghan
Hi Jon
WQuikscat has Elies in the Gulf with a low centre near Tanimbar Islands. As
per a recent discussion on the Tropical storm group this region of the
Indonesian Seas is affected by severe small TCs in Nov/Dec and April May.
The latest EC slowly develops an 850hPa vortex in this area over the next
36 hours.
Jeff

Jeff Callaghan:  Low-latitude midget TC's

From: Jeff Callaghan <j.callaghan@BoM.GOV.AU>
To: John McBride <jmb@BoM.GOV.AU>
Subject: Fwd: The limiting effect of the coriolis parameter on Tropical  Cyclogenesis may be
    overrated

John
this is the email sent to the storms group re low latitude midgets
Jeff
Date: Wed, 28 Nov 2001 01:23:41 +1000
>To: tropical-storms@tstorms.org
>From: Jeff Callaghan <j.callaghan@bom.gov.au>
>Subject: The limiting effect of the coriolis parameter on Tropical
>Cyclogenesis may be overrated
>
>Hi Group
>Alan Brunt in 1967 said something like the above in an excellent paper
>"Low latitude Cyclones" Aust Met Mag 1967
>vol 17 pp67-90. He thought that an important limiting factor on
>cyclogenesis may be the short time the monsoon trough may spend in these
>low latitude regions.
>
>The inspiration for the study was tropical cyclone "Annie" which developed
>near 6 deg S and caused widespread damage and loss of life in the maritime
>provinces of Papua New Guinea in November 1967. Since then two destructive
>midgets like "Annie' affected the region, "Hannah" in May 1972 and 'Adel"
>in  May 1993 which both developed near 5.5
>With the planned "Sunrise" production oil and gas platform to be located
>at 9.6S 128.1E there is an interest in these low  latitude systems. An
>initial inspection of tracks in the region suggest that the worst activity
>is south of the planned platform. However In the region equatorward of
>this planned installation, we know of some disastrous TC occurrences:-
>
>April 1973 a TC, with an IR image at 0140 UTC 29/4/1973 near 8S 121.5E
>looking like a clone of "Tracy", caused 1500 fishermen to be lost at sea,
>sunk a ship with the loss of 21 and caused 53 deaths on the Island of Flores.
>
>Dec 1960 Saumlaki (7.9S 131.3E) was virtually destroyed with most people
>left homeless, it caused 3 deaths and thousands of palm trees were uprooted.
>
>April 1960. The ship 'Straat Jahore" encountered a hurricane near 8.7S 129.1E
>
>April 1925 Yamdena (7.5S 131.5E) almost all houses were destroyed by a
>cyclone.
>On Selaru (8.0S 131.0E) 10 people were killed, hundreds of palms were
>blown down, most houses were damaged and storm surge destroyed much of the
>plantations.
>
>April 1908 Kisar Islands (8.0S 127.2E) 150 people killed by cyclone.
>
>1850 Kei Islands 5.8S 132.7E (Elderly inhabitants relate of a terrible
>cyclone in the 1850s when trees were uprooted).
>
>April 1843 Roti (10.6S 123.0E) 75 people killed by a cyclone and many
>homes were destroyed.
>
>April 1778 Banda Islands (4.5S 129.8E) Nearly all houses were unroofed
>over 4 hour period and 85% of nutmeg trees were destroyed. There was a
>similar event in 1811.
>
>Note that the occurrences both in the Indonesian area and the PNG area
>were bimodel; Nov/Dec as the monsoon trough passed south on its way down
>to Australia and April/May as it was retreating back to the NH.
>
>In this region just north of the equator typhoon "Kate" at 4.5N 131E
>reached  a minimum sea level pressure of 938 hPa (as reported from a
>reconaissance flight.)
>Kate went on to make landfall in the Davao Gulf of Mindanao (usually a
>typhoon free zone) and caused 631 deaths.
>
>Thanks to Mark Lander for the following reference re Kate
>Holliday, Charles R., Aylmer H. Thompson, 1986: An Unusual Near-Equatorial
>Typhoon. Monthly Weather Review: Vol. 114, No. 12. 2674
>
>Jeff

Geoff Garden:  TROPICAL CYCLONE OUTLOOK
Date: Mon, 08 Apr 2002 14:31:59 +0930
From: Geoffrey Garden <g.garden@BoM.GOV.AU>
To: j.mcbride@BoM.GOV.AU
Subject: Fwd: BOM: Darwin Tropical Cyclone Outlook
 

>Date: Mon, 8 Apr 2002 14:18:01 +0930
>From: Aifs Operational Manager <aifsop@Bom.Gov.Au>
>To: warn_sevwx@barra.nt.BoM.GOV.AU
>Subject: BOM: Darwin Tropical Cyclone Outlook
>
>IDD10610
>BUREAU OF METEOROLOGY
>Northern Territory Region
>Darwin Regional Forecasting Centre
>
>TROPICAL CYCLONE OUTLOOK
>
>TROPICAL CYCLONE OUTLOOK
>FOR THE AREA BETWEEN LONGITUDES 125 EAST - 142 EAST
>Issued by the BUREAU OF METEOROLOGY, DARWIN
>at 2:15 pm CST Monday 8 April 2002
>
>A developing TROPICAL LOW 1007 hPa is situated in the ARAFURA SEA.
>At 1pm it was near latitude 8.5S, longitude 132E, about 300 km north of Cape
>Don, and moving towards the west southwest at about 20 km/h.  The LOW is
>expected to continue moving towards the west or southwest across the northern
>TIMOR SEA on Wednesday. The low may develop into a tropical cyclone
>southwest of
>Timor on Thursday.
>
>The potential for development into a Tropical Cyclone over the next
>few days is estimated to be:
>      Tuesday:   low,
>      Wednesday: moderate,
>      Thursday:  high.
>
>NOTE: Development Potential is an estimate of the probability of tropical
>cyclone development for each day... Low = 10% or less, Moderate = 20% - 40%,
>High = 50% or more.
>
>DARWIN Regional Forecasting Centre.

Geoff garden:  tropical cyclone outlook
>Date: Mon, 8 Apr 2002 14:55:24 +0930
>From: Aifs Operational Manager <aifsop@Bom.Gov.Au>
>To: warn_sevwx@barra.nt.BoM.GOV.AU
>Subject: BOM: TC Outlook Prognostic Reasoning
>
>IDD10620
>BUREAU OF METEOROLOGY
>Northern Territory Region
>Darwin Regional Forecasting Centre
>
>TROPICAL CYCLONE OUTLOOK PROGNOSTIC REASONING
>- For Meteorologist Use Only -
>
>Issued by the BUREAU OF METEOROLOGY, DARWIN
>at 1430 CST Monday 8 April 2002
>
>I. ANALYSIS
>A weak low 1007 hPa is located in the Arafura Sea around 8.5S 132E, moving to
>the west southwest at 10 knots. Convection has increased against the diurnal
>trend in convergent flow to the south of the system, but remains disorganised
>[T1.5].  The building of the ridge along the Queensland coast is feeding a
>strengthening easterly flow into the system.  The mid-level ridge over
>Australia
>is weak, and has an ENE-WSW orientation. The upper-level ridge is south of the
>low, but there is good divergent upper flow above the system.
>
>II. PROGNOSIS
>Computer models analyse the system further north, and move it west across
>Timor
>on Wednesday, but given the current west-southwestward motion and the fact
>that
>there are no new influences expected to affect the steering flow during
>the next
>couple of days, the track of the system is expected to remain
>west-southwesterly.  This will bring the low closer to the upper ridge, and
>assuming development at a standard rate, would have it reaching cyclone
>strength
>on Wednesday in the northern Timor Sea or, more likely, southwest of Timor on
>Thursday.  However, if the low does move west across Timor, its
>development will
>be retarded by the interaction with land.
>
>III. TC OUTLOOK FORECAST
>Tuesday: Low.
>Wednesday: Moderate.
>Thursday: High.
>
>DARWIN Regional Forecasting Centre.

TC OUTLOOK April 9

>
>CANCELLATION OF WIND WARNING
>FOR COASTAL WATERS between Cape Fourcroy and Nhulunbuy.
>Issued by BUREAU OF METEOROLOGY, DARWIN
>at 1100 CST Tuesday 9 APRIL 2002
>
>PLEASE BE AWARE
>Wind gusts can be a further 40 percent stronger than the averages given here,
>and maximum waves may be up to twice the height.
>
>NOTE: latitudes and longitudes are in decimal degrees.
>
>SITUATION at 1100 CST
>A tropical low, 1008 hPa, was located near 7S 129.3E, about 300 nautical miles
>northwest of Cape Don, and moving west southwest at 7 knots.
>The low is no longer expected to develop and it is moving further away from
>Northern Territory waters.
>
>The Strong Wind Warning for coastal waters between Cape Fourcroy and Nhulunbuy
>has been cancelled as strong winds are no longer expected to develop. However
>fresh easterly winds should persist along the north coast and over the
>northern 1Gulf of Carpentaria for the next few days.