(ABOVE IMAGE) A National Weather Service image shows the latest 5 day track for Tropical Storm Ana.

(ABOVE VIDEO) Video contains the first Hawaii County Civil Defense message concerning Tropical Storm Ana.

NEWS BRIEFS

• A Tropical Storm Watch was issued for Hawaii County as of 5 p.m.
• Tropical Storm Ana is 545 miles southeast of Hilo, Hawaii. The storm is moving west at 10 miles per hour.
• Maximum sustained winds are near 60 miles per hour, with higher gusts. Ana is forecast to gradually intensify and may become a hurricane on Friday. Ana is expected to gradually turn toward the northwest by early Thursday, and maintain this motion through Friday. On the forecast track, the center of Ana will pass near the Big Island Friday night and Saturday.
• Governor Neil Abercrombie has signed an emergency proclamation. A number of closures have already been scheduled for Friday.

PRIMARY SOURCES

Ana is presenting a deteriorated satellite appearance this evening… As it continues to encounter moderate north to northwesterly shear. The shear also introduces uncertainty with respect to the current position of the low level center… But a 0402 utc ssmi/s pass confirms what earlier passes suggested… That the center remains displaced northwest from the deepest convection. Dvorak intensity estimates ranged from 3.0/45 kt to 3.5/55 kt… And given the recent satellite trends… The initial intensity for this advisory has been lowered to 50 kt.

The initial motion is nearly due west at 265/09 kt… To the south of a deep layer ridge. Latest guidance indicates that the ridge providing this steering flow will remain relatively unchanged through early Thursday… Before shifting slightly to the east later Thursday into the weekend. This will produce a northwestward steering flow… Which is expected to turn Ana toward the Hawaiian Islands. The latest track guidance aids remain tightly clustered… And are close to the previous forecast track. Thus the updated forecast track is similar to the previous… After accounting for the westward motion since the previous advisory. The track takes the center of Ana just south and west of the Big Island Friday night and Saturday… Then near Oahu and Kauai over the weekend. Forward motion of the cyclone is expected to slow over the weekend as steering currents weaken due to the passage of a low to the north. The NOAA Gulfstream iv sampled the near-storm environment earlier today… And is slated to fly again tomorrow… Providing valuable environmental data.

The intensity forecast remains a challenge. On one hand… More than adequate sea surface temperatures and an expected decrease in vertical wind shear would support intensification to a hurricane over the next day or two… In line with hwrf and ghm guidance. However… Ships and lgem have been consistently lowering the expected peak intensity over the past 24 hours.. And are not forecasting Ana to become a hurricane. The current deterioration of Ana in satellite imagery lends credence to these forecasts. The intensity forecast for this package is a blend of the two… But delays hurricane intensity until friday… With a peak intensity of 65 kt. If Ana fails to reorganize soon… Subsequent intensity forecasts may need to be nudged further downward.

It is important for people in the main Hawaiian Islands not to focus too closely on the exact forecast track of Ana. With an average 48 hour track error of approximately 80 miles… It is still too soon to say with much certainty which islands will be most likely to experience the worst weather. Everyone should be prepared for the possibility of direct impacts from Ana. It is also important to keep in mind that significant impacts from tropical cyclones can extend well away from the center. National Weather Service discussion on Oct. 15 at 11 p.m. HST