By PDC’s Senior Weather
Specialist Glenn James
Current Tropical Cyclones:
Typhoon 02W (Mawar)…is located approximately 395 NM south-southwest of Kadena AB, Okinawa
Northeast Pacific Ocean:
There are no tropical cyclones…nor any areas of disturbed weather under investigation by the National Hurricane Center (NHC)
Tropical cyclone formation is not expected during the next 7 days.
Western Pacific Ocean
Typhoon 02W (Mawar)
According to the JTWC Warning number 41, sustained winds were 80 knots, with gusts to 100 knots.
Animated enhanced infrared satellite imagery depicts adegraded convective appearance with the northern side of the storm in particular showing clear signs of significant erosion of the eyewall. A recent pass depicted a 25 NM wide, well-defined low-level eye structure, but a coincident microwave imagery showed a classic double eyewall structure, with a weak inner eyewall around 30 NM out from the center, and a more pronounced secondary eyewall around 50 NM out.
Analysis reveals a marginal environment characterized by warm sea surface temperatures and low vertical wind shear. The upper-level pattern however is somewhat odd, showing cyclonic divergent outflow, with a band of eastward outflow splitting off just south of Okinawa.
TY 02W has continued to slow down as it moves into a weak and competing steering pattern, with subtropical ridges centered over south-central China and south of Tokyo and a weakness in the deep-layer mean due north of the system. No significant change in either the strength or position of the competing ridge centers is expected through the next 48 hours, and TY 02W is forecast to slowly drift northward, and at times become quasi-stationary, generally moving towards the weakness in the
By 72 hours, the ridge to the east is expected to build, while a moderate-strength mid-latitude trough is expected to pass over Korea and Japan, both enhancing the steering gradient on the east side of the system and enticing the system poleward into the weakness in the ridge. TY 02W will eject poleward by 72 hours, and slowly accelerate to the northeast through 120 hours, though by the end of the forecast period, it is expected to still be in the vicinity of the Ryukyu Island chain.
In terms of intensity, the recent influx of dry air from the north has kicked off the weakening trend, even though conditions otherwise remain marginally favorable. Sea surface temperatures are already fairly low as the system is approaching a cold eddy and now that the system is forecast to slow to a crawl, upwelling will occur very rapidly and result in a rapid weakening trend through 72 hours.
After the system starts to move northeastward, sea water temperatures will continue to decrease, but the system will also tap into a poleward outflow channel into a jet max over Japan, offsetting the decrease in sea surface temperatures for a time as the system passes by Okinawa. However, between 96 and 120 hours the system begins subtropical transition and begins to rapidly weaken once more due to the decrease in sea surface temperatures, and a shot of cool, dry air from the north.