A thunderous negative phase of the Antarctic oscillation (-AAO) also referred to as Southern Annular Mode (SAM) is present in the southern hemisphere. The result is uncharacteristic deep upper troughs in the southern hemisphere middle latitudes. One of these troughs impacts South America weather.

The India/Southeast wet monsoon failed during mid-July to mid-August. Drought is developing across southern, western, and northern India. Drought continues in Thailand, parts of Vietnam, and Southern China. Conversely, parts of China have observed heavy rain and flooding.

A warmer than normal southeastern Pacific propels Hilary to a major hurricane late this week and eventually excessive rains and flooding in California while tropical rains soak Florida. Away from the wet weather, extreme heat and dryness dominates the Central and Mid-south U.S.

Two new tropical waves are apparent in the morning analysis. The first, located near 30W, is weak but expected to drift westward with some development possible over the next 5 days. NOAA/NHC indicates only a 10% chance of a tropical cyclone in the 3-5-day forecast. The second tropical wave, still over West Africa, is stronger with a 30% chance of tropical cyclone risk late this week.