Over the next several days, the system waxed and waned due to changes in wind shear before organizing into a tropical depression on July 10 while well southwest of Hawaii.

Halola crossed the International Date Line on July 13 and entered the Western Pacific, where it was immediately recognized as a severe tropical storm.

The storm further strengthened into a typhoon over the next day before encountering strong wind shear on July 16, upon which it quickly weakened into a tropical depression as it passed south of Wake Island.

On July 21, Halola regained typhoon status and later peaked with 10-minute sustained winds of 150 km/h (93 mph) and a minimum pressure of 955 hPa (mbar; 28.20 inHg).

The typhoon initially posed a significant threat to Wake Island, prompting the evacuation of all personnel from the military base spanning the atoll; however, no damage resulted from its passage.

Development temporarily halted late on July 7 after an upper-level anticyclone traveled northward, away from the center, causing easterly wind shear to affect the system.

The system continued to organize, developing into a tropical depression on July 10 at 06:00 UTC, while located approximately 1,650 km (1,030 mi) southwest of Honolulu, Hawaii.

Slow strengthening continued over the next couple of days, with the nascent depression being upgraded to Tropical Storm Halola by the Central Pacific Hurricane Center at 00:00 UTC on July 11.

[1] On July 13 at 00:00 UTC, Halola crossed the International Date Line and entered the Western Pacific,[1] falling under the purview of the Japan Meteorological Agency (JMA), which immediately recognized it as a severe tropical storm.

[2] Once in the Western Pacific, Halola began to intensify quickly, developing a small 15 km (9.3 mi) wide eye and good outflow channels.

Although the eye feature quickly disappeared, convection continued to deepen and Halola reached its initial peak intensity at 06:00 UTC with 10-minute sustained winds of 130 km/h (81 mph).

[4][2] The US-based Joint Typhoon Warning Center (JTWC) simultaneously judged Halola to have 1-minute sustained winds of 155 km/h (96 mph), equivalent to Category 2 on the Saffir–Simpson scale.

[2] Convection became sheared to the east of the low-level circulation center as Halola passed south of Wake Island on July 16, reflecting the disorganized state of the system.

[2] As the system tracked steadily westwards under the influence of a strong ridge, it was met with dry air that further limited thunderstorm activity through July 18.

[2] The eye contracted to a diameter of 9 km (5.6 mi) as the storm strengthened,[11] eventually reaching peak intensity at 18:00 UTC on July 21 with 10-minute sustained winds of 150 km/h (93 mph) and a minimum pressure of 955 hPa (mbar; 28.20 inHg).

[12][13] Halola remained a well-organized and compact system through July 22 despite worsening outflow,[14] with the JTWC assessing that it had once again attained 1-minute sustained winds of 155 km/h (96 mph) at 12:00 UTC.

[23] That day, a Boeing C-17 Globemaster III aircraft from the Hawaii Air National Guard was used to evacuate 125 Department of Defense personnel deployed on Wake Island due to the threat of storm surge.

This was subsequently extended on July 24 to cover Sasebo and Marine Corps Air Station Iwakuni while the bases on Okinawa were placed under TCCOR 2.