Hawaii Extended Forecast Discussion NWS Weather Prediction Center College Park MD 817 AM EDT Wed Jul 16 2014 Valid 00Z Thu Jul 17 2014 - 00Z Thu Jul 24 2014 ...Tropical Wave this Weekend... The trades are forecast to be interrupted by a tropical wave approaching Hawai'i from the southeast this weekend. The 00Z/16 high-resolution ECMWF indicates that the heart of the 850-millibar circulation and deep-layer moisture should pass slowly along the island chain Saturday through Tuesday. The ECMWF shows a plume of precipitable water in excess of 2.00 inches affecting the state during this time period. The plume is capable of fueling many inches of rainfall, with a direct track of the low-level vorticity across the high terrain the worst-case scenario with upwards of a foot. That small-scale detail is still beyond the scope of the time range of the event, but the threat should be noted. While not presently expected by the National Hurricane Center to become a full-blown tropical cyclone, winds in the high terrain could gust in excess of 35kts over the weekend. Cisco