2009-Typhoon Mirinae (23w) #1(Short Report)

Updated at 2009-10-28 18:30 HKT

Short Description

Mirinae has been intensified into Typhoon and tracked westward to west-northwestward in the past few hours. It is expected to make landfall on the northern Philippines and will bring threat to Philippines.

Track Analysis

Typhoon Mirinae, located about 750 kilometers north of Yap, is forecast to move west. From the numerical model, the strength of the high pressure steering ridge will be invariant and it is steering Mirinae westward within few days and will be approaching the eastern coast of Luzon.

Strength Analysis

As mentioned by JTWC, the strong zonal flow across southern Japan in the upper level becomes the primary mechanism for poleward outflow (shown in fig1). Also, there is an upper level anticyclone located to the east of the system which will enhance the equaterward outflow. Therefore, the upper level divergency channel has been maintained after the lifting out of the mid-latitude trough.

Figure 1 - Wind Field in Layer 200hPa of ECMWF model

The atmosphere allow the strengthening of Mirinae and it is forecast to become a Category 3 Typhoon before landfall with the maximum wind speed near 190kph in one minute average. The circulation of Mirinae will become more organized and the outer rainbands will effect the eastern Luzon on about Friday.

Organization Cyclone Information:

+ HKO(10-min avg): TY120 km/h
+ JMA(10-min avg): TY145 km/h
+ CWB(10-min avg): TY125 km/h
+ JTWC#10(1-min avg): TY160 km/h

Appendix

Figure 2 – Sea level Pressure of ECMWF model after 24 hrs

Figure 3 – Sea level Pressure of ECMWF model after 72 hrs

Figure 3 – Geopotential 500 hPa of ECMWF model after 72 hrs

From the images above, it reveals that Mirinae keep intensifying. Also, it tracks westward beneath the subtropical ridge before coming ashore near Philippines.