sentences:  Strong influence from the monsoonal westerlies left the depression drifting and slowly executing a loop to the northwest.Based on sufficient satellite classifications, JTWC upgraded the depression to Tropical Storm Isa early on April 12 while it was located 105 km (65 mi) of Pohnpei.The Japan Meteorological Agency (JMA) simultaneously classified the system as a tropical depression, and upgraded it to a tropical storm early on April 13.