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Atlantic Tropical Depression #2 Weakens to TROF as it Heads for Caribbean

By: Dr. Jeff Masters, 5:17 PM GMT on July 23, 2014

(By Steve Gregory - Substituting for Dr. Masters who is on Vacation.)

Former Tropical Depression #2 is estimated to be near 14.1N / 56.2W or about 300NM east of the CARIB, and is heading westward (290ᵒ) at 17Kts. Imagery loops along with a few surface OBS any clearly indicate TD #2 opened-up into an inverted TROF early this AM; and one with a minimum of significant convection.


Fig 1: The above VIS (left) and Enhanced IR (right) image of former TD #2 depicts an extremely weak and poorly organized area of convection.

Although the decrease in convection was partially due to typical diurnal variation, the disturbance encountered stronger wind shear and drier air that ultimately destroyed the already borderline circulation. In addition, the disturbance will be encountering even stronger wind shear over the next 48 hours, and the chances of re-development are NIL.


Fig 2: TD-2 ran into increasing shear overnight, and this appears to be the primary reason TD-2 is no longer…

Anything up Elsewhere in the Atlantic?


Fig 3: The precipitable water graphic shows an increase in moisture associated with the ITCZ, though drying due to the intrusion of the SAL is also shown over the Cape Verdes ahead of the next, albeit somewhat weaker wave now emerging off the African coast.


Fig 4: This unique ‘convective’ image for northern Africa (along with related loop imagery and 850mb Vorticity analysis – not shown) helps identify the next set of upstream tropical waves over central and western Africa.

The tropical wave analysis using the above Convective imagery indicates a moderately strong wave with some mid-level turning over west central Africa (2nd from the coast) and a much stronger wave developing over east central Africa (far right in above image) with significant low to mid-level rotation evident. Both of theses waves will be moving over the Atlantic next week. However, in the meantime, no cyclone formation is currently expected for the next 6 or more days.

Typhoon MATMO over mainland China

MATMO crossed Taiwan yesterday with numerous wind reports supporting CAT 2 intensity at landfall. While crossing Taiwan, it weakened to a CAT 1, with additional weakening due to friction affects and increasing wind shear as it crossed the Taiwan Strait. The storm made it’s 2nd landfall along the SE coast of China between 06Z and 07Z today. The system is now moving northward, and will transition to a non-tropical Low as it moves more rapidly N/NE during the next 2 days – with heavy rainfall it’s primary threat.


Fig 6: MATMO is seen ‘unwinding’ rapidly in the above IR image, with most of the significant convection far removed from the center of the cyclone.


Fig 7: The latest color enhanced IR image of MATMO indicates very strong convection remains along the coast and over the open waters well south of the storm center.

Winds are likely still gusting to tropical storm intensity over land, while winds are likely near CAT 1 intensity in the stronger convective bands over the open water.

Although there are 3 other ‘Invests’ over the West Pacific – none of these are expected to develop into cyclones during the next 48 hours.

The next update will be coming from Dr. Jeff Masters on Thursday.

For those interested , I will once again be providing my own Weather Updates starting the week of AUG 18 at Steve Gregory

Steve Gregory


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