"I ran into icing at about 8000 ft on my way into Virginia. It was clear on top and when I descended through a layer my windshield froze over instantly. Airspeed went from 250 to 150 in a descent, wings were icing even though I had deicing switched on. I was flying a T-210 and had flown in snow and ice before but nothing like this. I reported the icing to ATC, but didn't declare an emergency. Then my engine decided to quit even though I had sufficient fuel, switched tanks and it fired up again. I landed on instruments and about half power. Windshield never did thaw till we left several days later. Would have been nice to have known about the icing before my descent. I would have diverted. Should ATC be required to notify you of icing?" - Greg K.
“First, never be reluctant to declare an emergency. The PIC should consider the situation as described an imminent situation where the safe outcome of the flight is in doubt.
Second, ATC is required to report icing if known. Generally, the only way it is known is through a PIREP. There may or may not have been other aircraft in the area at the time and at the same altitude. ATC RADAR only detects precipitation not necessarily icing or turbulence.
There are some great new weather forecasting tools available on the Aviation Digital Data Service website. This website contains a graphical depiction of Current and Forecast icing conditions along with current PIREPS.
However, nothing beats a good old briefing from Flight Service if you suspect challenging conditions. The Internet sites are great, but a trained briefer can help you evaluate the situation.
Also be aware of your aircraft POH limitations – most light aircraft are prohibited from flying in known icing conditions.”