Upper Shear Keeps Deep Tropics Quiet While Chris Almost Became A Major Hurricane

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Chris narrowly missed strengthening to a category 3 major hurricane while the remains of Beryl follows Chris and could reorganize. In the deep tropics upper westerly shear maintains a quiet pattern.

Fig. 1: Morning IR satellite view of Cat-2 Hurricane Chris starting to lose a well-defined eye present last night as system moves toward cooler water.

Discussion: Chris intensified rapidly overnight as surface pressure lowered to 970 MB. Intensification was caused primarily by increased inflow to the center of Chris induced by increased outflow across the top of Chris triggered by an approaching upper trough. Chris is moving over the warm Gulf Stream also helping intensification. During the past 2-3 hours Chris is shifting toward less warm surface water causing the previously well-defined eye to fade. NOAA/NHC indicates Chris remains a hurricane moving northeast to the east of New England. Weakening could be quicker due to acceleration of Chris into much cooler waters. Meanwhile the remains of Beryl is likely to follow Chris late week/weekend possibly organizing to a weak tropical cyclone well east of the Carolinas this weekend. The upper shear pattern is strong across the North Atlantic basin characteristics of an El Nino climate.

Fig. 2: Morning IR satellite view of the North Atlantic basin identifying northeastward moving Cat-2 Hurricane Chris which may weaken more quickly than the indicated NOAA/NHC forecast track (red = hurricane). The remains of Beryl follows Chris. The upper shear axis keeps the deep tropics quiet.