Because the models are having significant issues with H5. The standard room for error at h5 encompasses some of these potential changes.
One slightly different phase and your whole storm is different. Can't always just take models lock stock and barrel
In theory... High resolution short range models should have your best shot here
The GFS is more than likely to not come around until the last minute. Likewise, this is not the GFS wheel house.
If it is the GFS alone, you will have several very well respected models vs a global at short range.
I may have jumped the gun there... but that H5 -if it comes to fruition- will disappoint no one here.
I can't remember seeing that type of H5 on the models since I started tracking... about 20 years ago.
I believe the crawling monster is very possible, if not likely (not sure about that low a mb but), however, those on Long Island should also prepare for what comes along with that.
The PNA ridge ebbing up and down has been able to cut off the southern stream energy there. The progressive pattern allows for the ebbing and flowing, while also cutting off some energy in the four corners region.
At hr 36 you can see the southern stream is much better and being allowed to interact with the Northern stream. This is much better. Orientation is better as well.