TheIronSheik
SUPER ELITE UPPER TIER
Dr. Jeff Masters update:
INVEST 98L and ‘EX INVEST 97L’
While NHC dropped 97L early yesterday – it added INVEST 98L earlier this morning. INVEST 98L in the NW GOM originated at the ‘tail end’ of a very strong mid-level Dry Line that surged south/southwest from the SE US across Florida and into the northern Gulf of Mexico (GOM) 2 days ago – triggering a line of very strong T-storms along and ahead of it. While the dry line boundary has begun to fade away (though relatively dry air continues to dominate much of the GOM) a small surface circulation has formed in the NW GOM, centered about 200NM east of Corpus Christi, TX. An area of convection, with some isolated deep convection, is near and to the North and Northeast of the Low itself. The convection and surface circulation is quasi-stationary, and with wind shear of 30Kts over most of the system, significant development is unlikely for at least the next 24 hours. The first run of specialized tropical cyclone models (12Z cycle) are in remarkably good agreement on forecasting the system to move slowly westward into south Texas in 48-72 hours. With a generally anti-cyclonic flow aloft, and some of the warmest SST’s seen in years in this part of the GOM, and falloff in wind shear to under 15Kts could allow this small disturbance to spin-up prior to moving inland.
' EX INVEST 97L' STILL WORTH WATCHING’
While yesterday’s Global model runs had forecast what was 97L to develop into a significant cyclone, the last few runs have completely backed away on this. However, most of the global models now forecast this elongated wave near the eastern CARIB to move across the CARIB towards the Yucatan over the weekend, with some models showing a small cyclone formation in the southern GOM next week.
There has been a dramatic increase in moisture both with the westbound wave and from the deep (Equatorial) tropics in South America (SOAMER) that has been surging northward ahead of the wave for over 24 hours. Though wind shear is over 30Kts over much of the eastern CARIB (and will remain relatively high for the next few days) there is a somewhat anti-cyclonic flow developing between a small upper air Low/TROF in the west central CARIB and the approaching tropical wave in the far eastern CARIB. This anti-cyclonic curvature of the high level wind field may develop further and move westward as the tropical wave traverses the CARIB over the next few days – and shear speeds may drop off during the weekend. Clearly a system worth monitoring over the coming days.
STRONG DISTURBANCE STILL WESTBOUND OVER AFRICA
One of the season's strongest ‘Cape Verde’ disturbances is emerging off the West African coast, with virtually all global models forecasting the system to gradually intensify over the weekend as it heads West/Northwest. This strong wave with a cyclonic circulation system has a long history since it developed in the highlands of east-central Africa last weekend and has maintained a low-mid level circulation and significant convection as it crossed north Africa. The most reliable models (especially the GFS) have consistently shown this system developing into a strong cyclone early next week – but also show the system turning Northwestward and eventually northward as it approaches the central Atlantic. The latest (00Z) model run has shown this recurvature occurring a bit further west than earlier runs - but the ‘theme’ of ultimately turning this system out to sea before it can impact the CARIB or US remains unchanged.