July 21-25, 1986 (HURRICANE ESTELLE)

Hurricane ESTELLE developed a few days earlier on July 16 in the eastern North Pacific near 10N 115W. ESTELLE crossed 140W and into the CPHC area at 210600Z. ESTELLE was a well developed and quite powerful hurricane during the previous 24 hours when maximum sustained winds were estimated at 115 knots. While in the area between 130W and 140W, ESTELLE was moving toward the west northwest at 20 knots and maintained this forward motion after it crossed 140W.

The synoptic weather pattern over the North Pacific during ESTELLE's early days had been rather unique for mid summer with strong pressure features more reminiscent of winter. A large trough in the upper westerlies was located off the west coast of North America during the formative stages of ESTELLE. This trough retrograded toward the west and was in the vicinity of the Hawaiian Islands as ESTELLE made her approach from the east and, for a time, it appeared that it could recurve to the east of the Islands or become sheared as the upper westerlies descended in both altitude and latitude near the cyclone. In any event, ESTELLE started to weaken gradually on the 21st and continued this slow decline over the next few days as it moved rapidly west and approached the Hawaiian Islands.

The rapid forward motion of about 20 knots on a course aiming directly at the Hawaiian Islands during this intense stage of ESTELLE's life resulted in some very large swell that moved toward the Big Island of Hawaii. With the wave energy and the cyclone's moving at approximately the same speed, the swell bunched up and hit the east facing shores of the Big Island with high intensity during the afternoon hours of July 22. All beaches along the southeast coast of the Big Island were evacuated before 10 to 20 foot surf began to pound the shoreline. The waves from ESTELLE came at a time of spring tides near full moon and during a period of high water induced by the cyclone itself as strong northeast winds, gusting to near 50 knots, blew parallel to the Puna and Ka'u Coast and piled the water to the right of the wind toward shore. This caused the swell waves from the southeast to break higher up on the beach and, in the process, demolished five beach front homes and caused heavy damage to several others in the Vacation Land subdivision. Total dollar damage on the Big Island was estimated at $2 million.

On the island of Maui, the wave action on the eastern coast caused a stretch of dirt road between Kipahulu and Kaupo to be washed away. On the island of Oahu, two drownings occurred on July 23 and may have been caused by the rough waters associated with ESTELLE.

NOAA buoy 51004 proved to be a valuable observing platform. Forecasters at the CPHC were able to obtain vital wind, pressure, and wave data as ESTELLE approached the Big Island and Buoy 51004. The lowest pressure, peak wind, and largest wave height was reported at 222300Z when ESTELLE was about 30 miles south of 51004. The lowest hourly sea level pressure reported was 1000.6 mb, the maximum 10 minute average winds 080 degrees 52 kt gusting as high as 66 knots, and the largest waves reported 21 half meters (34.4 feet).

A U.S. Air Force reconnaissance aircraft flying into the center of ESTELLE fixed the surface position at 17.0N 152.6W at 222307Z. This position is exactly 30 nm south of Buoy 51004. The reconnaissance aircraft reported measured sea level pressure of 981 millibars in the center of ESTELLE and observed maximum winds within the northwest quadrant of 52 knots at a distance of 60 nautical miles from the center.

ESTELLE moved along a very predictable westward track near 20 knots from 140W to 155W. The west northwest track turned west near 150W as the flow carrying ESTELLE was influenced by the upper trough. ESTELLE moved almost due west along 17N between 150W and 160W. The closest point of approach to the southernmost tip of the Big Island occurred about 231000Z when ESTELLE's center passed about 120 miles to the south with maximum sustained winds estimated at 75 knots. Winds over the Big Island were not particularly strong and were estimated at 40 to 50 miles per hour locally in exposed areas. Rainfall was also light during the passage of the tropical cyclone south of the island. However, heavy showers did subsequently occur when ESTELLE was located to the southwest of the Big Island and moisture was spreading north behind the storm.

Some 48 hour rainfall amounts ranging between 5 and 10 inches were reported over the Ka'u and Puna districts.

ESTELLE was downgraded to a tropical storm at 231800Z. The storm continued to weaken as it moved on a more north of west track and was downgraded to a tropical depression at 250000Z. The final advisory on ESTELLE was issued by the CPHC at 260600Z when the remnants of the once powerful tropical cyclone was located near 19N 166W. The EPHC and the CPHC issued a total of 40 advisories on ESTELLE, which denotes a tem day life span.

Moisture laden air carried along by ESTELLE interacted with the dynamics of an upper trough to the north of the Islands during the dissipating stage and caused heavy thunderstorms over most of the Hawaiian Islands. Rainfall amounts of 4 to 7 inches fell on portions of Oahu on the 24th and 25th.

There were no reports of serious damages or casualties to ships attributed to ESTELLE.

July 27-28, 1986 (TROPICAL DEPRESSION ONE-C)

Tropical Depression ONE-C was tracked westward along 11N at a fairly rapid forward speed of 20 to 25 kt. The data are sketchy, but it is possible that ONE-C was formed from the remnants of Tropical Depression EIGHT-E, which had dissipated a few days earlier well to the east of 140E. Several radio reports from ship ABQJ on the 27th and 28th were helpful in locating the depression's center. TD1C failed to develop past the depression stage. It passed well south of the Hawaiian Islands on the 28th with no noticeable effects on the Islands' weather. At 280000Z, it was dissipating to the southwest of the Hawaiian Islands and the final advisory was issued.

July 29-30, 1986 (TROPICAL DEPRESSION TEN-E)

Tropical Depression TEN-E had been a steady state tropical depression for about 3 days before moving into the Central Pacific. TD10E crossed 140W near 12N on July 29 at about 1000Z. A slow weakening began as the depression continued to move west at near 15 knots. By 301800Z near 12N 148W, it had become poorly organized and the final advisory was issued.

August 1 - 2, 1986 (TROPICAL DEPRESSION FRANK)

Tropical depression Frank entered the CPHC area near 12N 140W at 020000Z. The depression had been a tropical storm just 12 hours earlier. FRANK had maximum sustained winds estimated at 30 knots and was moving northwest at 15 knots. FRANK was slowly losing strength as it was moving over slightly cooler waters and additionally encountered unfavorable upper winds that tended to shear its circulation.

The CPHC issued its last advisory on FRANK at 030300Z as it was considered dissipating and transforming into a weak extratropical system.

August 3- 4, 1986 (TROPICAL STORM GEORGETTE)

Tropical Depression GEORGETTE crossed into the CPHC area at a rather low latitude of 08N. The system had earlier been a tropical storm and was in a weakening trend moving westward at a rather rapid pace of 20 to 30 kt just south of 10N. GEORGETTE was upgraded to tropical storm status once again at 041200Z as satellite imagery indicated some intensification when in the vicinity of 09N 145W. The gathering of strength was short lived, however, as GEORGETTE relapsed into a decline. The final advisory was issued at 042100Z as satellite imagery showed GEORGETTE's circulation had merged into the deep convection associated with the ITCZ and was dissipating. The CPHC issued just 4 advisories on the weak tropical system.

September 16, 1986 (TROPICAL DEPRESSION LESTER)

LESTER was already under the adverse effects of strong vertical shear across its circulation for the 24 hours before crossing 140W and into the CPHC area about 161800Z. LESTER, on crossing 140W, was downgraded to a tropical depression. It was moving northwest about 10 knots in a rather unusual low level flow, which featured a broad trough or low pressure system just north of the Hawaiian Islands.

All that remained of LESTER at 170000Z was a weak low level circulation with no sign of a closed isobars at the surface. The final advisory on LESTER was issued at this time.

September 21-24, 1986 (HURRICANE ORLENE)

Hurricane ORLENE formed out of Tropical Depression 22-E, which developed within an active trough to the southwest of Tropical Storm MADELINE in the vicinity of 10N 140W on the 21st. The EPHC issued the first few advisories as the poorly defined center was located just east of 140W and there was a good chance that TD22E would recurve and follow MADELINE toward the north northeast. TD22E became Tropical Storm ORLENE at 211200Z near 13N 139W. A few hours later, a distinct eye could be seen developing in satellite imagery and the EPHC upgraded the tropical storm to a hurricane at 212300Z and passed the responsibility for the issuance of advisories to the CPHC.

ORLENE tracked almost due north just west of 140W with maximum sustained winds estimated between at 65 and 70 knots. ORLENE soon started to move into an environment with unfavorable strong southwesterlies aloft and slightly lower sea surface temperatures. This resulted in shearing and rapid weakening near 16.5N 141.5W and the subsequent downgrading to a tropical storm at 231800Z. Stripped of its upper level circulation, the low level remains of Tropical Storm ORLENE took on a westerly course along 17N at a relatively slow rate of 5 to 10 kt. At 241800Z, ORLENE was downgraded to a tropical depression near 17N 144W. The final advisory was issued a few hours later at 250000Z at 260000Z as the remains of ORLENE drifted slowly west.