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

NEWS BRIEFS

• Hawaii County remains under a Tropical Storm Watch
• Tropical Storm Ana is 250 miles south of Hilo, Hawaii. The storm is moving west northwest at 14 miles per hour. This direction expected to continue this morning, with a slight turn to the northwest later today and Saturday. A decrease in forward speed is expected Saturday night and Sunday. On this forecast track, the center of Ana will pass about 125 miles southwest of the Big Island tonight and about 130 miles southwest of the rest of the main Hawaiian islands this weekend. Tropical storm force winds extend outward up to 80 miles from the center.
• 70 mph, 110 km/h, with higher gusts. Gradual strengthening is expected during the next 24 hours, with Ana possibly becoming a hurricane later today or tonight. Gradual weakening is expected Saturday and Sunday.
• The National Weather Service says “based on the latest forecast, there is little chance for hurricane conditions at this time. Also, the chance for tropical storm conditions at this time is 20 percent at South Point, 16 percent at Kailua Kona, and 8 percent at Hilo.”

PRIMARY SOURCES

Thankfully, Tropical Storm Ana has continued to shift somewhat to the west, but it is still a powerful storm that still could be upgraded to hurricane strength. Ana is moving West-Northwest at 14 mph, and our island remains under a tropical storm and flash flood watch, and we all need to stay alert. Our schools remain closed as is our county beach parks. County and State offices are open today. The National Weather Service is predicting heavy rains of six to eight inches on the Island of Hawaii, and winds of 20 mph to 40 mph with stronger gusts. Surf is already picking up, and surf heights of 10 to 20 feet are expected on our southeast shores. Surf in the 8 to 10 feet plus range is expected on our southwest shores. The center of the storm is expected to be at its closest point to the Island of Hawaii at 2 a.m. Saturday morning. Please be safe, and please be prepared!Mayor Billy Kenoi on Facebook, Oct. 17

Ana continues to produce bursts of deep convection near and east of the center… With impressive outflow in the north and east semicircles. Satellite imagery showed what appeared to be a banding type eye on the western edge of the deep convection around midnight… But that feature quickly eroded… With westerly shear near 10 kt likely preventing Ana from organizing more efficiently. Data from a u.S. Air force Reconnaissance Aircraft confirmed that Ana is close to hurricane strength… With maximum flight level winds of 72 kt in the northwest quadrant… And maximum sfmr winds of 54 kt. A blend of the available data supports increasing the initial intensity to 60 kt for this advisory. The next penetration of the cyclone by the aircraft is scheduled for this afternoon… While the NOAA g-iv will be flying another synoptic mission today.

The initial motion estimate is the same as the previous advisory… 295/12 kt. A slight turn toward the northwest is expected later today and Saturday… As the deep layer anticyclone centered to the northeast of Ana is nudged eastward by a mid-latitude trough passing well northeast of the Hawaiian Islands. Late Saturday and Sunday a new ridge is forecast to build north of Ana… Resulting in a slowing in the forward motion… And a turn toward the west… Just as the system approaches Kauai county and Oahu from the south. Latest track guidance continues the trend of the past 48 hours… Shifting west with each successive run… Especially at these time ranges. The latest forecast track follows the previous forecast closely in the short term… And continues to lie on the right side of the guidance envelope. In the longer range the track forecast has been shifted westward… In concurrence with the dynamic guidance… And toward the ecmwf solution… Which has been verifying well over the past 48 to 72 hours. By days 4 and 5…Ana is forecast to be near the Papahanaumokuakea Marine National Monument.

Modest intensification is expected through tonight… With light to moderate westerly shear preventing significant strengthening despite water temperatures increasing along the forecast track. The forecast calls for Ana to strengthen to a hurricane in the short term… But the window for strengthening is still expected to close on Saturday…At least temporarily. This is due to the passing mid-latitude trough imparting increased vertical wind shear. The official forecast lies between the ships and lgem guidance… But is weaker than the icon consensus. The consensus forecast is deemed to be too high… As the hwf and gfdi make Ana a 100 kt hurricane by day 4… Despite increasing shear. This strengthening trend occurs as Ana reaches the anomalously warm waters northwest of the main Hawaiian Islands… With the variance in forecast models due to the differing forecast shear profiles in the longer ranges. National Weather Service discussion on Oct. 17 at 5 a.m. HST