90L is on the cusp tonight and appears likely to begin tracking poleward as a strengthening tropical cyclone.

Some 20/0z model runs:

20/0z GFS turns 90L north as a strengthening TC, taking it across the Dominican Republic as a 992mb 50KT tropical storm. After crossing the island the GFS has the cyclone undergo further intensification, becoming a strong Cat 1/2 hurricane traveling north-northwest towards Bermuda and then crossing the island nation from the southeast overnight Saturday Aug 26th as a Cat 2 hurricane

20/0z HWRF Threads the needle in between between the passage of the Dominican Republic and Puerto Rico overnight Tuesday Aug 22nd as a strong Cat 1, then proceeds north-northeast bringing the cyclone to Major Hurricane by 25/0z, winding down as it tracks north-northeast away from land.

20/0z HMON Drives 90L into the DR overnight on the 22nd as a 995mb 50KT tropical storm. Once having crossed that island, HMON never really revs it up much, opting instead to keep it a sloppy tropical storm/eventual hybrid, tracking north-northeast away from land.

20/0z HAFSA Strengthens 90L into a strong storm or perhaps Cat 1 while south of DR/PR on Monday the 21st, then takes the cyclone over the DR on Tuesday 22nd. End of run near 26.5N 64.5W while tracking north-northeast at Cat 1 and back up to Cat 1 after having weakened over DR.