Kammala jumla mai zuwa: Irma ya sake yin karfi a cikin guguwar rukuni na 3 a 12:00 UTC a ranar 3 ga Satumba yayin da ya koma kudu maso yamma a ƙarƙashin tasirin dutsen. Tun daga farkon rana mai zuwa, idon ya fara girma da kuma kyautata bayyanarsa, yayin da zurfin da ke kewaye da ido ya zama mafi daidaituwa. Bugu da ƙari, guguwar ta shiga cikin yanayin zafin teku mai zafi yayin da ta kusanci tsibirin Leeward. Sakamakon haka, Irma ya sake fuskantar wani lokaci na saurin tsanantawa, ya kai matakin 4 a 18:00 UTC a ranar 4 ga Satumba da kuma matsayin 5 a 12:00 UTC a ranar 5 ga Satumba. Hurricane mai karfin gaske ya girma a girma kuma ya zama mai karuwa, yana samun halaye na annular, tare da mesovortices da aka lura a cikin ido mai ma'ana, yana nuna ci gaba da tsananta guguwar. Iska mai ci gaba ta kai 180 mph (285 km / h) kusa da 18:00 UTC a ranar 5 ga Satumba <unk> duk da cewa an tantance aikin a 185 mph (295 km / h). A farkon Satumba 6, guguwar ta kai ƙaramar matsin lamba na iska na kusa da 06:00 UTC, ƙididdigar da aka yi dangane da lura da matsin lamba da ma'auni daga Barbuda da Saint Barthélemy. Wannan shi ne mafi ƙasƙanci barometric matsa lamba a cikin Atlantic tun
Dean a shekara ta 2007.