Narrative:

Flight to ZZZ departed XA27 on 05/mon/05. After checking WX at FBO using WX radar and metar/taf information decided to depart for ZZZ with some storm activity south of my departure area and southwest of my planned route of flight. Approximately 15 NM northwest of tyler I encountered some lowering visibility so I adjusted course more westerly; started to slow airspeed with lowering visibility. After a few mins decided VFR conditions could not be held and due to the dark (low surface lighting) conditions that a 180 degree turn would not be the best course of action. Entered IMC in a climb straight ahead to a safe altitude 4000 ft. Contacted approach and declared an emergency. Followed directions and clrncs given. Continued IFR to ZZZ runway 31R ILS. Cancelled IFR on final approach in VFR conditions; continued to hospital VFR. Landed at ZZZ XB17. Contacted my operations management.

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Original NASA ASRS Text

Title: HELI PLT VFR ENRTE TO ZZZ INADVERTENTLY ENTERS IMC. DECLARED EMER; OBTAINS IFR CLRNC UNTIL ONCE AGAIN IN VMC AND CONTINUES TO DEST.

Narrative: FLT TO ZZZ DEPARTED XA27 ON 05/MON/05. AFTER CHKING WX AT FBO USING WX RADAR AND METAR/TAF INFO DECIDED TO DEPART FOR ZZZ WITH SOME STORM ACTIVITY S OF MY DEP AREA AND SW OF MY PLANNED RTE OF FLT. APPROX 15 NM NW OF TYLER I ENCOUNTERED SOME LOWERING VISIBILITY SO I ADJUSTED COURSE MORE WESTERLY; STARTED TO SLOW AIRSPEED WITH LOWERING VISIBILITY. AFTER A FEW MINS DECIDED VFR CONDITIONS COULD NOT BE HELD AND DUE TO THE DARK (LOW SURFACE LIGHTING) CONDITIONS THAT A 180 DEG TURN WOULD NOT BE THE BEST COURSE OF ACTION. ENTERED IMC IN A CLB STRAIGHT AHEAD TO A SAFE ALT 4000 FT. CONTACTED APCH AND DECLARED AN EMER. FOLLOWED DIRECTIONS AND CLRNCS GIVEN. CONTINUED IFR TO ZZZ RWY 31R ILS. CANCELLED IFR ON FINAL APCH IN VFR CONDITIONS; CONTINUED TO HOSPITAL VFR. LANDED AT ZZZ XB17. CONTACTED MY OPS MGMNT.

Data retrieved from NASA's ASRS site as of January 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.