Followup to the above 12Z UKMET post regarding the new MDR AOI:
I just looked at the last 4 UKMET runs and discovered that the reason the latest run recurves this AOI into Erin is because Erin is further SW due to a further W recurve and thus doesn’t exit until a couple of days later than yesterday’s runs:
UKMET progs for 0Z 8/22:
1) 0Z 8/15 run at 168 hrs:
Erin 954 mb at 38N, 59W after recurve at 70W
AOI 1011 mb at 20N, 61W, is 1,250 miles to the S
2) 12Z 8/15 run at 156 hrs:
Erin 949 mb at 42N, 57W after recurve at 70W
AOI 1006 mb at 18N, 62W, is 1,700 miles to the SSW
3) 0Z 8/16 run at 144 hrs:
Erin 962 mb at 37N, 66W after recurve at 73W
AOI 1007 mb at 16N, 59W, is 1,500 miles to the SSE
4) 12Z 8/16 run at 132 hrs:
Erin 958 mb at 35N, 71W after recurve at 74W
AOI 1006 mb at 20N, 57W, is 1,350 miles to the SE moving NW to the S of retreating H5 ridge
Conclusion:
It isn’t just about how fast the AOI moves W and develops, but also and possibly more crucially it is about how far W Erin recurves. The further W Erin recurves, the longer it will take for her to exit. The later the exit, the better chance the AOI would have to recurve before reaching the Conus.
