We now have 3 tropical waves in the outer tropical North Atlantic basin. Each tropical wave is located over 80-81F water which is marginally supportive for development. The upper shear axis stretches across the southern Caribbean Sea and northwest of the tropical waves. However, the shear axis is not particularly strong. Meanwhile upper shear is very light across the northern Caribbean Sea and Bahamas (where surface water is generally warmer than normal).

The most impressive upper level feature in the northern hemisphere since springtime has been the persistent and vigorous upper level cool and showery trough over Western Russia. Occasionally, upstream from the deep trough an amplified ridge forms to bring heat wave conditions to Europe centered on France. Otherwise the trough takes over and squashes heat and this time leads to wet weather over France next week after the torrid heat this week.

The Australian Bureau of Meteorology has updated their Indian Ocean Dipole outlook which indicates a robust positive phase evolving for AUG/SEP/OCT 2019.

Dynamic global SSTA forecast models including NCEP CFS V2, NMME and GFDL are suddenly forecasting La Nina cooling in the eastern equatorial Pacific Ocean for AUG/SEP/OCT 2019. The possible cause for this sudden change picked up by most global models is the rapid cooling off the West Coast of South America the past few weeks forced northward into the East Pacific tropics by the reactivated Humboldt Ocean Current. The just-ending El Nino warm waters shift west to the Dateline. Interestingly, if the La Nina cooling forecast is less dramatic an El Nino Modoki may form.