Over the past two days, tropical cyclone Meari has tracked north-northwestward from the maritime sub-continent toward China and is presently located between Taiwan and Japan.
The Joint Typhoon Warning Center forecasts Meari to move northward, making landfall on the Korean Peninsula at around 1200 UTC 26 June.
|Source: Joint Typhoon Warning Center|
As shown in the GFS loop below, Meari is not expected to undergo extratropical transition (at least during this 5 day period). It weakens following landfall, but as can be seen in the dynamic tropopause analysis (top panel), it does contribute to the development of a high amplitude ridge over Japan.
There is, however, another cyclone in this case, an extratropical cyclone that develops over the northwest Pacific and moves into the Bering Sea. Downstream of this feature a pronounced upper-level ridge forms over the Gulf of Alaska and contributes to a sharp trough that develops off the Pacific Northwest coast.
There is great uncertainty in regards to the position and intensity of this trough. If we look at the GFS ensemble, one can see wide ranging solutions. In some, the trough moves onshore as an open wave, in others it closes off upstream of California. This makes quite a bit of difference in the weather for folks in the Pacific Northwest!
|Source: Penn State Meteorology E-Wall|