Tag Archives: SH10

Tropical Cyclone Desmond Brings Wind and Rain to Mozambique

Tropical Cyclone Desmond brought wind and rain to Mozambique on Monday.  At 4:00 p.m. EST on Sunday the center of Tropical Cyclone Desmond was located at latitude 18.8°S and longitude 36.3°E which put it about 25 miles (40 km) west of Conceicao, Mozambique.  Desmond was moving toward the west-northwest at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 40 m.p.h. (65 km/h) and there were wind gusts to 50 m.p.h. (80 km/h).  The minimum surface pressure was 1000 mb.

Tropical Cyclone Desmond made landfall in Mozambique near Ponta Timbue on Monday.  Thunderstorms developed on the western side of the circulation where the winds were blowing toward the land.  Those thunderstorms were dropping heavy rain over parts of Mozambique.  The strongest winds were occurring along the coast of Mozambique and over the Mozambique Channel.  Winds to tropical storm force extended out about 100 miles (160 km) on the eastern side of Tropical Cyclone Desmond.  Wind speeds were slower over land.

Tropical Cyclone Desmond will move around the eastern end of a subtropical high pressure system over southern Africa.  The high will steer Desmond toward the north-northwest.  On its anticipated track Tropical Cyclone Desmond will move farther inland over the Zambezi River toward southern Malawi.  Desmond will drop locally heavy rain over parts of the lower Zambezi River basin and flooding could occur in some locations.

Tropical Cyclone Desmond Forms Over Mozambique Channel

Tropical Cyclone Desmond formed over the Mozambique Channel on Sunday.  At 4:00 p.m. EST on Sunday the center of Tropical Cyclone Desmond was located at latitude 21.3°S and longitude 39.0°E which put it about 250 miles (400 km) south-southeast of Quelimane, Mozambique.  Desmond was moving toward the north at 6 m.p.h. (10 km/h).  The maximum sustained wind speed was 45 m.p.h. (75 km/h) and there were wind gusts to 60 m.p.h. (95 km/h).  The minimum surface pressure was 997 mb.

Thunderstorms developed closer to the center of a low pressure system over the Mozambique Channel on Sunday and the system was designated Tropical Cyclone Desmond.  The distribution of thunderstorms around Desmond was very asymmetrical.  Most of the stronger thunderstorms were occurring in bands southeast of the center of circulation.  Bands in other parts of the circulation consisted of showers and lower clouds.  An upper level trough just southeast of Africa was producing northwesterly winds which were blowing toward the top of Tropical Cyclone Desmond.   Those winds were causing moderate vertical wind shear and they were probably the reason for the asymmetrical distribution of thunderstorms.

Tropical Cyclone Desmond will move through an environment somewhat favorable for intensification during the next 24 to 36 hours.  Desmond will move over water where the Sea Surface Temperature is near 29°C.  The upper level trough is forecast to move eastward and the vertical wind shear could decrease.  Tropical Cyclone Desmond could strengthen when the shear decreases, if it is still over water.

Tropical Cyclone Desmond will move around the eastern end of a subtropical ridge in the middle levels over southern Africa.  The ridge should steer Desmond in a north-northwesterly direction.  On its anticipated track Tropical Cyclone Desmond will move toward Mozambique and it could make landfall within 36 hours.  However, there is another low pressure system near northern Madagascar.  If the circulations of the two low pressure systems interact, then Desmond could be pulled farther to the north.

Stronger Tropical Cyclone Kelvin Makes Landfall in Western Australia

A stronger Tropical Cyclone Kelvin made landfall on the coast of Western Australia near Anna Plains on Saturday night.  At 10:00 p.m. EST on Saturday the center of Tropical Cyclone Kelvin was located at latitude 19.4°S and longitude 121.9°E which put it about 60 miles (95 km) east-northeast of Sandfire, Australia.  Kelvin was moving toward the east-southeast at 8 m.p.h. (13 km/h).  The maximum sustained wind speed was 75 m.p.h. (120 km/h) and there were wind gusts to 95 m.p.h. (155 km/h).  The minimum surface pressure was 975 mb.  The Australian Bureau of Meteorology issued a Warning for the portion of the coast from Broome to Wallal Downs and the Warning extends inland to include Telfer.

Tropical Cyclone Kelvin intensified very rapidly before it made landfall on the coast of Western Australia.  Kelvin strengthened in a few hours from a minimal tropical storm to the equivalent of a hurricane/typhoon.  A small circular eye developed at the center of circulation.  The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in the ring of storms.  Bands of showers and thunderstorms were revolving around the core of the circulation.  Kelvin was a small tropical cyclone.  Winds to tropical storm force only extended out about 60 miles (95 km) from the center of circulation.

Tropical Cyclone Kelvin intensified enough to be capable of causing wind damage, but locally heavy rain is the greater risk.  The small size of Kelvin will limit the area of heavy rain, but there could be enough rain in some areas to create the potential for floods.  The Australian Bureau of Meteorology issued Flood Warnings for the North Kimberly District, the West Kimberly District, and the Sandy Desert.  Flood Watches were issued for the De Grey Rivers and the Salt Lake District Rivers.  Tropical Cyclone Kelvin will weaken as it moves farther inland, but Kelvin will take longer to spin down because it strengthened so much before landfall.

Tropical Cyclone Kelvin Develops Near Western Australia

Tropical Cyclone Kelvin developed near the coast of Western Australia on Saturday.  At 1:00 p.m. EST on Saturday the center of Tropical Cyclone Kelvin was located at latitude 19.2°S and longitude 120.9°E which put it about 60 miles (95 km) north-northeast of Wallal Downs, Australia.  Kelvin was moving toward the east at 4 m.p.h. (6 km/h).  The maximum sustained wind speed was 45 m.p.h. (75 km/h) and there were wind gusts to 60 m.p.h. (95 km/h).  The minimum surface pressure was 988 mb.  The Australian Bureau of Meteorology issued a Warning for the portion of the coast from Broome to Pardoo Roadhouse and the Warning extended inland to include Telfer.

A Tropical Low meandered near the coast of Western Australia during the past several days.  The Tropical Low moved off the coast and strengthened into Tropical Cyclone Kelvin on Saturday.  The circulation of Kelvin is small.  Winds to tropical storm force only extend out about 60 miles (95 km) from the center of circulation.  Even though it is small, the circulation of Tropical Cyclone Kelvin is well organized.  There is a distinct low level center of circulation.  Thunderstorms are occurring near the center of circulation.  Additional bands of showers and thunderstorms are revolving around the core of Tropical Cyclone Kelvin.  The storms in the core are generating upper level divergence which is pumping away mass.

Tropical Cyclone Kelvin will move through an environment favorable for intensification during the next few hours.  Kelvin will move over water where the Sea Surface Temperature is near 30°C.  It is moving near the southwestern end of an upper level ridge and the upper level winds are weak.  There is little vertical wind shear.  The only factor inhibiting intensification is the proximity to the coast of Western Australia.  Tropical Cyclone Kelvin is likely to intensify until it makes landfall on the coast of Western Australia.  Kelvin should gradually weaken when it moves inland.

The upper level ridge is steering Tropical Cyclone Kelvin slowly toward the east.  That general motion is forecast to continue for several more hours.  Kelvin is likely to move more toward the southeast when it nears the coast.  On its anticipated track Tropical Cyclone Kelvin could make landfall on the coast of Western Australia between Bidyadanga and Wallal Downs within the next 12 hours.  Kelvin will bring gusty winds to the coast, but locally heavy rain and flooding are greater risks.  The Australian Bureau of Meteorology has issued Flood Warnings for the North Kimberly District and the West Kimberly District,  Flood Watches have been issued for the Kimberly and North Pilbara District catchments.  An Initial Flood Warning has been issued for the Sandy Desert.

Tropical Cyclone Blanche Strengthens Near Coast of Western Australia

Tropical Cyclone Blanche strengthened on Sunday as it moved over the Timor Sea toward the coast of Western Australia.  At 7:00 p.m. EST on Sunday the center of Tropical Cyclone Blanche was located at latitude 14.0°S and longitude 128.2°E which put it about 100 miles (165 km) north of Wyndham, Australia.  Blanche was moving toward the southwest at 11 m.p.h. (17 km/h).  The maximum sustained wind speed was 60 m.p.h. (95 km/h) and there were wind gusts to 80 m.p.h. (130 km/h).  The minimum surface pressure was 988 mb.

The inner core of Tropical Cyclone Blanche became more organized on Sunday.  A band of thunderstorms wrapped about two thirds of the way around the southern and western portions of the center.  The band has the appearance of a partial eyewall.  The strongest winds are occurring in the band near the center.  The thunderstorms are generating upper level divergence which is pumping out mass to the west and southeast of the Tropical Cyclone Blanche.  The upper level divergence allowed the surface pressure to decrease and the wind speed to increase.

Tropical Cyclone Blanche will be over the Timor Sea for a few more hours.  It will be in an environment that is favorable for intensification during that time.  Blanche will move over water where the Sea Surface Temperature is near 29°C.  An upper level ridge east of Blanche is producing northerly winds which are blowing toward the tropical cyclone.  The winds are causing moderate vertical wind shear, but the shear was not strong enough to prevent intensification on Sunday.  Tropical Cyclone Blanche could intensify a little more before it makes landfall.

A subtropical ridge is steering Tropical Cyclone Blanche toward the southwest and that general motion is expected to continue.  On its anticipated track Tropical Cyclone Blanche will make landfall on the coast of Western Australia northwest of Wyndham in a few hours.  Blanche will bring gusty winds and some storm surge to the coast.  It will cause locally heavy rain and the potential for flooding as it moves inland.

Tropical Cyclone Blanche Forms Northwest of Darwin

Tropical Cyclone Blanche formed northwest of Darwin, Australia over the Timor Sea late on Saturday.  At 10:00 p.m. EST on Saturday the center of Tropical Cyclone Blanche was located at latitude 11.9°S and longitude 130.3°E which put it about 55 miles (85 km) northwest of Darwin, Australia.  Blanche was moving toward the southwest at 7 m.p.h. (12 km/h).  The maximum sustained wind speed was 40 m.p.h. (65 km/h) and there were wind gusts to 60 m.p.h. (95 km/h).  The minimum surface pressure was 993 mb.

An area of low pressure moved north of the Northern Territory over the Arafura Sea during the past few days.  The low exhibited enough organization for the Australian Bureau of Meteorology to designate it as a tropical low.  The center of the low moved across Melville Island and Bathhurst Island earlier today.  More and stronger thunderstorms began to form closer to the center after it moved over the Beagle Gulf and into the Timor Sea.  The increased convection and organization prompted the Australian Bureau of Meteorology to name the system Tropical Cyclone Blanche.

Although the circulation of Tropical Cyclone Blanche became better organized today, it is still somewhat asymmetrical.  Many of the stronger thunderstorms are occurring in a band south and west of the center or circulation.  Bands north and east of the center contain mainly lower clouds and showers.  An upper level ridge to the east of Blanche is producing northerly winds which are blowing toward the top of the tropical cyclone.  The vertical wind shear appears to have increased during recent hours and the upper level divergence to the east of the center has been reduced.  Part of the lower level circulation appears to becoming exposed on the most recent visible satellite images.

Tropical Cyclone Blanche will be moving through an environment that contains both positive and negative factors.  Blanche will move over water where the Sea Surface Temperature is near 29°C.  So, there is sufficient energy in the upper ocean to support intensification.  However, the upper level ridge to the east of Blanche is producing moderate vertical wind shear, which appears to have stalled intensification for now.  If the wind shear remains moderate, then Blanche will not strengthen.  If the wind shear increases, it could blow the upper portion of the circulation away from the lower part and the tropical cyclone would weaken.  On the other hand if the wind shear decreases, then Tropical Cyclone Blanche could intensify a little more.  There is a great deal of uncertainty about the future intensity of Blanche.

Blanche is moving around the northwestern portion of a subtropical ridge, which is steering the tropical cyclone toward the southwest.  This general motion is expected to continue.  On its anticipated track Tropical Cyclone Blanche will move across the Timor Sea and make landfall on the coast of Western Australia between Wyndham and Kalumburu in 24 to 36 hours.  Tropical Cyclone Blanche could bring some gusty winds, but the primary risk will be locally heavy rainfall and the potential for flooding.