Narrative:

During a VFR EMS flight to an accident scene, unforecasted WX was encountered. The pilot was unable to continue safely under VFR conditions so the pilot elected to climb into IMC conditions in controled airspace without a clearance. After initiating the climb, the pilot contacted center to advise them of the situation and to obtain a clearance. The rest of the flight proceeded uneventfully.

Google
 

Original NASA ASRS Text

Title: AN EMS HELI RUNS INTO IMC WHILE OUTBOUND ON A MISSION. BEING TOO LOW TO CONTACT ATC THE PLT CLBS IMC TO OBTAIN AN IFR CLRNC.

Narrative: DURING A VFR EMS FLT TO AN ACCIDENT SCENE, UNFORECASTED WX WAS ENCOUNTERED. THE PLT WAS UNABLE TO CONTINUE SAFELY UNDER VFR CONDITIONS SO THE PLT ELECTED TO CLB INTO IMC CONDITIONS IN CTLED AIRSPACE WITHOUT A CLRNC. AFTER INITIATING THE CLB, THE PLT CONTACTED CTR TO ADVISE THEM OF THE SIT AND TO OBTAIN A CLRNC. THE REST OF THE FLT PROCEEDED UNEVENTFULLY.

Data retrieved from NASA's ASRS site as of July 2007 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.