West Pacific And North Indian Ocean Invest Thread 2010

[Somerset Squall]

This thread is to discuss all invests (disturbances suspect for tropical cyclone development) that occur during 2010. A thread will be made for all invests that are upgraded to Tropical Cyclone status.

Well, not much going on in the West Pacific or North Indian Ocean at the moment as both are in their quiet phases. However, even at this time of year tropical cyclones can form just not as frequently as in the Summer.

[Cookie]

thanks for doing this mate.

not a great deal to talk about at the moment, anywhere around the globe.

I cant see 2010 being as active as 2009

[Somerset Squall]

West Pacific:

Invest 93W has developed in the South China Sea, just off the east coast of Vietnam. A circulation is rapidly consolidating and convection is wrapping tightly into the centre. This development is happening in spite of high shear. Sea temps are favourbale for a tropical depression to form, and indeed, 93W seems close already. May have the first storm of 2010 in the West Pacific if trends continue!

North Indian Ocean:

No invests.

[Cookie]

93W

[Somerset Squall]

West Pacific:

93W became Tropical Depression 01W.

Invest 98W has formed around 2.5N 153.5E, approx 300 miles southeast of the island of Chuuk. Convection is steadily increasing over a developing LLC, despite the proximity to the equator. Conditions are favourable with low shear, sea temps of 29C, and good upper level outflow which could help the LLC develop further. JTWC give the system a fair chance of becoming a TC within the next 24hrs, but I think it may take a little longer than that if at all as the system really does need to move further north from the equator so it can acquire more spin.

North Indian Ocean:

No invests.

[Somerset Squall]

West Pacific:

98W has become better organised over the last 24hrs. Deep convection continues to build and has started to wrap in towards a slowly consolidating LLC. With favourable conditions set to persist, this one may become a tropical depression in the next day or so if organisational trends continue.

North Indian Ocean:

No invests.

[Somerset Squall]

West Pacific:

98W looks impressive on satellite imagery, with deep convection exploding over an increasingly well defined LLC. JTWC have issued a tropical cyclone formation alert on the system. Warm waters, low shear and high moisture favours continued development.

North Indian Ocean:

No invests.

[Cookie]

98W

Special Statement by NWS Guam

http://www.prh.noaa.gov/guam/

000

WWPQ80 PGUM 202153

SPSPQ

SPECIAL WEATHER STATEMENT

NATIONAL WEATHER SERVICE TIYAN GU

753 AM CHST SUN MAR 21 2010

PMZ161-171-212000-

KOROR PALAU-YAP-

753 AM CHST SUN MAR 21 2010

...DEVELOPING TROPICAL DISTURBANCE MOVING TOWARD YAP AND PALAU...

A TROPICAL DISTURBANCE LOCATED ABOUT 600 MILES SOUTH OF GUAM NEAR

5N145E IS MOVING WEST-NORTHWEST AT 10 TO 15 MPH AND INTENSIFYING.

BASED ON ITS CURRENT MOVEMENT AND FORECAST MODEL GUIDANCE...THIS

DISTURBANCE IS EXPECTED TO MOVE IN THE GENERAL DIRECTION OF YAP AND

PALAU OVER THE NEXT TWO DAYS...WITH THE CORE CONVECTION ASSOCIATED

WITH THIS SYSTEM PASSING BETWEEN YAP AND BABELTHUAP IN THE REPUBLIC

OF PALAU AROUND TUESDAY. RESIDENTS OF YAP AND PALAU CAN EXPECT

PERIODS OF HEAVY RAIN AND STRONG GUSTY WINDS MONDAY NIGHT THROUGH

TUESDAY NIGHT AS THIS DISTURBANCE PASSES BY. WINDS 20 TO 25 MPH WITH

GUSTS TO 35 MPH IN HEAVIER SHOWERS ARE POSSIBLE AT YAP AND PALAU.

RESIDENTS ARE ADVISED TO CLOSELY MONITOR THE MOVEMENT AND DEVELOPMENT

OF THIS TROPICAL DISTURBANCE OVER THE NEXT TWO TO THREE DAYS FROM THE

NATIONAL WEATHER SERVICE...AVAILABLE MEDIA SOURCES...THE INTERNET...

AND NOAA WEATHER RADIO. PRECAUTIONARY MEASURES TO SECURE SMALL BOATS

AND ANY PERSONAL PROPERTY THAT MAY BE EASILY BLOWN AROUND IS ADVISED.

RESIDENTS SHOULD REFER TO THEIR LOCAL EMERGENCY MANAGEMENT OFFICE

FOR THE LATEST INFORMATION. THE NATIONAL WEATHER SERVICE WILL UPDATE

THIS STATEMENT AS NEW INFORMATION BECOMES AVAILABLE.

$$

MUNDELL

[Cookie]

90W

[Somerset Squall]

West Pacific:

98W became Tropical Storm Omais.

As Cookie indicated above, invest 90W formed a few days ago, several hundred miles southeast of the Philippines. The disturbance has moved northwestwards with little development so far, especially yesterday when the system was moving over land and looked to be dissipating. However, 90W is looking more healthy again as it enters the South China Sea. The convection is showing signs of fairly strong rotation though it is not clear whether it is at low levels. Waters in the southern half of the South China Sea are warm, and shear throughout this region is also low. These conditions are conducive for further development, and if the rotation extends to the surface then a tropical depression may form over the next day or so from 90W.

North Indian Ocean:

No invests.

[Somerset Squall]

West Pacific:

90W dissipated.

Invest 91W has formed to the southeast of the Philippines. The disturbance lies at just 5 degrees north and as a result is only showing signs of weak rotation and is little more than a tropical wave. However, waters are now quite toasty at around 29C in the region, and shear is low which could promote some slow development of 91W.

North Indian Ocean:

There are no invests still in this basin, but it is worth noting is a disturbance does reach this region then it has the potential to become something big as the lack of activity has led to some extremley hot, undisturbed waters of around 33C:

[Cookie]

Theirs going to be a huge amount of un disturbed waters around. as its gone very quite yet again.

do you still think theirs chance of something cropping up in the souther hemisphere?

[Somerset Squall]

Not much I don't reckon, as shear is very high is large swathes of the Southern Hemisphere as the pattern is very much Winter type now. If a system does form then it's most likely to be near the equator around Indonesia where shear is lower for longer.

I've been keeping my eye of the North Indian Ocean for a while. The monsoon is late for India, and the lack of tropical disturbances has been notable, especially as May is supposed to be the first of two peaks (the other is November) in tropical cyclone activity for the basin. You can see the extent of the hot waters aswell so things could explode if the disturbed weather finally arrives.

The active South Pacific season this year quickly shut down too with no activity in April, the last month of the season. In fact, April only had two tropical cyclones worldwide, and they were both weak and shortlived, and both in the South Indian Ocean. There seems to be very little in the way of monsoon troughs in the West Pacific too at present, though activity tends to increase here June onwards. May is the quietest month worldwide on average, but things do seem to be VERY quiet at the moment. A lull before some increased activity? We shall see.

[Cookie]

thanks mate, interesting to read you're thoughts.

[Somerset Squall]

West Pacific:

No invests.

North Indian Ocean:

Invest 92B has formed in the southeastern Bay of Bengal, 750 miles south of Kolkata, India. Disorganised convection is showing signs of rotation around a very broad cyclonic system. Sea temps are hot and shear is low. However, given the current disorganised appearance of the system, further development could be quite slow.

Invest 93A has formed in the Arabian Sea, 500 miles southeast of Socotra Island. Convection is showing signs of rotation around some pronounced turning. It appears the system lacks a well defined LLC at present, but shear is low, waters warm and outflow is excellent in the region, which could allow one to spin up quite quickly. Given the good environment and already organised convection, I think there is a fair chance of this one becoming the first tropical cyclone of the North Indian Ocean season over the next day or so.

[Cookie]

93A

THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 8.5N 57.2E,

IS NOW LOCATED NEAR 9.9N 56.5E, APPROXIMATELY 325 NM EAST-SOUTHEAST

OF CAPE GUARDAFUI, SOMALIA. RECENT ANIMATED MULTISPECTRAL IMAGERY

SHOWS WELL DEFINED LOW- AND MID-LEVEL CYCLONIC TURNING WITH DEEP

CONVECTION ASSOCIATED WITH CONVERGENCE ALONG THE WESTERN PERIPHERY

OF SYSTEM. ENVIRONMENTAL ANALYSIS SHOWS THE SYSTEM IN APPROXIMATELY

20KTS OF VERTICAL WIND SHEAR AND NEAR AN UPPER LEVEL OUTFLOW SOURCE

THAT IS PROVIDING GOOD VENTING. MAXIMUM SUSTAINED SURFACE WINDS ARE

ESTIMATED AT 20 TO 25 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED

TO BE NEAR 1006 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A

SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS REMAINS FAIR.

Edited May 16, 2010 by cookie

[Somerset Squall]

West Pacific:

No invests.

North Indian Ocean:

92B has become much better organised today, with a well defined LLC rapidly developing. In addition, convection has become more concentrated and is consolidating into bands flanking the LLC. The system yesterday was still broad and disorganised, so this is a sign that a tropical cyclone could be rapidly forming. Waters are an extremely hot 32-33C, shear is very low, and outflow is excellent in all directions. We could have the first cyclone of the season later tonight or early tomorrow at this rate.

93A has not become any better organised. Strong rotation is noted still in the mid to upper levels, but the LLC remains weak. In addition, 93A is moving into much drier air as it inches westwards towards Somalia. Also, shear has increased which has significantly reduced convection associated with the system. Time is running out for 93A to become a tropical cyclone, chances are certainly decreasing.

Edited May 17, 2010 by Somerset Squall

[Cookie]

92B

this system has shot up rapidly

deep bursts of convection through today,

[Somerset Squall]

West Pacific:

No invests.

North Indian Ocean:

92B became Tropical Cyclone Laila.

93A has become much better organised as shear has eased and the region has become moister. Deep convection is building near a developing circulation which has finally extended to the surface. Waters are hot, shear is now low and outflow towards Yemen is very good. Therefore, this one could well become a tropical cyclone by morning. If it does, it will mean two cyclones active together in the North Indian Ocean, which is not common.

[Cookie]

93W

THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 17.3N

113.2E, IS NOW LOCATED NEAR 19.7N 115.4E, APPROXIMATELY 170 NM

SOUTH-SOUTHEAST OF HONG KONG. ANIMATED INFRARED SATELLITE IMAGERY

AND A 261819Z AMSU-B MICROWAVE IMAGE DEPICT CURVED CONVECTION AND

IMPROVED INFLOW INTO A LOW LEVEL CIRCULATION CENTER (LLCC).

ADDITIONALLY, NEARBY OBSERVATIONS INDICATE 15 KNOT WEST-

SOUTHWESTERLY WINDS. UPPER LEVEL ANALYSIS SHOWS THE SYSTEM IS

LOCATED JUST SOUTH OF THE SUBTROPICAL RIDGE AXIS IN AN AREA OF

MODERATE NORTHEASTERLY VERTICAL WIND SHEAR. MAXIMUM SUSTAINED

SURFACE WINDS ARE ESTIMATED AT 15 TO 20 KNOTS. MINIMUM SEA LEVEL

PRESSURE IS ESTIMATED TO BE NEAR 1007 MB. DUE TO IMPROVED

CONVECTIVE ORGANIZATION AND HIGH SEA SURFACE TEMPERATURES ANALYZED

AROUND 29 DEGREES CELSIUS, THE POTENTIAL FOR THE DEVELOPMENT OF A

SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS UPGRADED

TO FAIR.

[Somerset Squall]

West Pacific:

93W continues to consolidate in the South China sea. The invest is moving into an area of decreasing shear, and waters are very warm in the region. Convection is flaring, but not yet persisting near an increasingly well defined LLC. JTWC have issued a tropical cyclone formation alert on the system, so they must invisage the low shear and hot waters fuelling some rapid development.

North Indian Ocean:

93A became Tropical Cyclone Bandu.

[Somerset Squall]

West Pacific:

93W is on the verge of dissipation. I stated above that the JTWC issued a TCFA obviously thinking 93W would develop rapidly. It would have had to be rapid, as 93W did not have persistant convection. However, they may have been over eager on this one, as shear has completely stripped convection away from a distorted LLC. 93W is moving quickly northeastwards towards cooler waters around Taiwan, where the system will dissipate or become a weak extratropical storm.

North Indian Ocean:

No invests.

[Somerset Squall]

West Pacific:

93W dissipated.

North Indian Ocean:

Invest 94A has formed in the central Arabian Sea. The system has been consolidating quite quickly today, with deep convection now persisting over an area of increasingly pronounced turning. Conditions are favourable in the upper levels, with low shear and strong poleward outflow which should further tighten the LLC. At the surface, sea temps are a toasty 31C. If current trends continue, don't be surprised to see this one become a tropical cyclone as soon as tomorrow. If it does, it would be the third of the month, which is somewhat unusual in this basin.

[Cookie]

94A

[Cookie]

94A

starting to look more organized