Tropical Cyclone 11E / Tropical Cyclone 12W (Hinnamnor) / Tropical Cyclone 13W
Thursday, September 1, 2022

Current Snapshot

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By PDC’s Senior Weather
Specialist Glenn James

Tropical Cyclone 11E…is located 280 miles south of Cabo San Lucas, Mexico

Tropical Cyclone 12W (Hinnamnor)…is located approximately 335 NM south-southwest of Kadena AB, Okinawa

Tropical Cyclone 13W…is located approximately 163 NM south-southeast of Kadena AB, Okinawa – Final Warning

Northeast Pacific:

Tropical Cyclone 11E

TROPICAL DEPRESSION FORMS OFF THE SOUTHERN BAJA CALIFORNIA PENINSULA COAST

The depression is moving toward the northwest near 10 mph and this motion with some increase in forward speed is expected during the next couple of days.

Maximum sustained winds are near 35 mph with higher gusts. Slow strengthening is forecast during the next 36 to 48 hours, and the depression is expected to become a tropical storm tonight or on Friday.

HAZARDS AFFECTING LAND  

SURF: Swells generated by the depression are expected to affect portions of the southern and central Baja California peninsula. These swells are likely to cause life-threatening surf and rip current conditions.  

RAINFALL: Tropical Depression Eleven-E is expected to produce 1 to 2 inches of rainfall, with isolated storm totals of 3 inches across southern portions of Baja California Sur through Friday.

>>> South of southern Mexico:

A tropical wave is producing disorganized showers and thunderstorms near the Gulf of Tehuantepec.

Gradual development of this system is expected, and a tropical depression is likely to form late this weekend or early next week while it moves westward or west-northwestward near the coast of southern and southwestern Mexico.

* Formation chance through 48 hours…low…20 percent
* Formation chance through 5 days…high…70 percent

Central Pacific:

There are no tropical cyclones nor any areas of disturbed weather under investigation by the CPHC

Northwest and Southwest Pacific Ocean, Indian Ocean, Arabian Sea:

Tropical Cyclone 12W (Hinnamnor)

According to the JTWC Warning number 19, sustained winds were 115 knots with gusts to near 140 knots.

Animated enhanced infrared satellite imagery depicts eroding deep convection over the northern semicircle due to increasing northeasterly vertical wind shear. However, the system has retained a cloud-filled eye and fragmented spiral banding over the western semicircle. A microwave image still shows a round 12 NM microwave eye feature with the bulk of the core convection over the southern semicircle and extensive deep convective banding around the western and southern peripheries.

Environmental conditions have degraded with increasing easterly vertical wind shear and decreasing poleward outflow due to convergence associated with an upper-level trough to the northeast and an upper-level ridge to the northwest.

TY 12W is forecast to slow and stall through the next 24 hours with erratic, quasi-stationary motion expected. The system will weaken primarily due to cool upwelling water to around 90 knots.

After 24 hours, a mid-latitude shortwave trough is expected to dig over central China, which will weaken the western ridge and allow the
subtropical ridge to the east to assume the primary steering influence. Consequently, TY 12W will accelerate northward along the western periphery of the ridge through 72 hours.

Re-intensification is anticipated as poleward outflow improves into the strong westerlies over the Korean Peninsula with favorable sea surface temperature values.

TY 12W will recurve toward South Korea and western Japan as it tracks around the ridge axis and begins to interact with the midlatitude westerlies. The system will commence extra-tropical transition near Cheju-do and will rapidly transition into an extra-tropical low in the Sea of Japan.

Tropical Cyclone 13W – Final Warning

According to the JTWC Warning number 6, sustained winds were 25 knots with gusts to near 35 knots.

Animated enhanced infrared satellite imagery depicts a fully exposed low level circulation center with tightly wrapping low level cloud lines. A microwave image reveals that 13W is under relentless northeasterly shear due to the outflow from 12W which is 260 NM northwest.

TD 13W is forecast to track generally northwestward along the eastern periphery of TY 12W. While the system is currently being limited by the outflow from 12W, there is a shrinking opportunity for development near 12 hours.

Once 13W escapes this repressive outflow and moves parallel to 12W the outflow environment should improve dramatically, model fields suggest limited eastward and poleward outflow from TY 12W and development of an equatorward and eastward outflow channel for TD 13W.

This new outflow pattern coupled with the already warm sea surface temperatures and mild vertical wind shear could allow for a period of brief intensification to a peak of approximately 40 knots by 24 hours. After 24 hours, 13W will continue to interact with TY 12W until fully dissipating as a separate and distinct circulation center by 36 hours with an intensity near 40 knots.

Unlike previously forecasts the latest run of HWRP-P is no longer indicating the long shot intensification to typhoon strength before striking Kadena and orbiting 12W, nevertheless, the JTWC will continue to monitor all possible permutations as binary interaction can be highly complex and unpredictable.