UNCTLED AIRSPACE IN PROX OF PART TIME ATCT; ATCT CLOSED; TIED UP AS ZLC HOLDS IFR DEP TIME FOR PREVIOUSLY CANCELED FLT ARRIVING AT TWF; ID.

Narrative

AT AA30 AM LCL MDT I RECEIVED THE CALL TO GO ON AN AIR AMBULANCE FLT FROM BOI TO TWF AND TRANSPORT A BABY. DUE TO THE FACT THAT WX HADN'T BEEN RPTED FROM TWF; I HAD TO FILE A FLT PLAN TO BOI VIA TWF. FAR 135 SAYS YOU CANNOT FILE AN IFR FLT TO A DEST WITH NO WX. I FELT I HAD TO FILE IFR DUE TO THE FACT THAT THERE WAS A 3000 FT CEILING AT BOI AT THE TIME AND I WAS UNSURE WHAT WAS AT MY DEST. AFTER TKOF I LEVELED AT 11000 FT MSL AND APPROX 40 NM FROM BOI; BROKE INTO CLR SKIES. I THEN TOLD ZLC THAT I WANTED TO LAND IN TWF AND HE SAID OK; 'CLRED FOR APCH OR RPT TWF IN SIGHT FOR THE VISUAL.' A SHORT TIME LATER THE CTR CTLR ASKED HOW LONG I WOULD BE IN TWF; AND I TOLD HIM I WOULD BE AIRBORNE WITHIN AN HR. HE THEN ISSUED MY RETURN CLRNC AND SQUAWK; WHICH I ACKNOWLEDGED. AT APPROX 25 DME FROM TWF I TOLD THE CTLR I WANTED TO CANCEL MY IFR CLRNC AND REMAIN WITH HIM FOR VFR ADVISORIES. SALT LAKE ACKNOWLEDGED AND SHORTLY THEREAFTER TERMINATED FLT FOLLOWING. I LANDED AT AB30 AM MDT. AT AB30 PLUS 2:30 I RETURNED TO THE ACFT AND WAS TOLD TO CALL THE TWR. APPARENTLY; ZLC HAD KEPT THE AIRSPACE UNTIL THE TWR WAS OPENED AT AC00 AM MDT. THEY WERE UPSET. I DON'T KNOW HOW TO CORRECT THE SIT; ESPECIALLY WHEN I CANCELED MY CLRNC WITH THE CTLR. PERHAPS FOLLOW-UP WITH A PHONE CALL?