GA pilot reported landing at a closed airport due to adverse flight characteristics caused by icing.

Attributes
ACN	1512360
Time
Date	201801
Local Time Of Day	1201-1800
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Make Model Name	PA-28R Cherokee Arrow All Series
Operating Under FAR Part	Part 91
Flight Phase	Initial Approach
Route In Use	Vectors
Flight Plan	IFR
Person 1
Function	Single Pilot
Qualification	Flight Crew Multiengine Flight Crew Flight Instructor Flight Crew Instrument
Experience	Flight Crew Last 90 Days 30 Flight Crew Total 2500 Flight Crew Type 1500
Events
Anomaly	Deviation - Procedural FAR Deviation - Procedural Published Material / Policy Ground Incursion Runway Inflight Event / Encounter Weather / Turbulence

Narrative:

While on IFR flight plan to I encountered unforecast icing conditions just north of ZZZ while on vector to the ILS. I immediately requested a 180 turn-out due to icing; toward my departure airport; which was also my filed alternate. Within a couple minutes; there was significant ice accumulation such that there were significant unfavorable flight characteristics. No longer able to maintain altitude; I requested a vector to the nearest airport. A vector was given to ZZZ1. Although ATC did not advise the airport was closed; I already knew it was because I saw the NOTAM previously when I had considered this an alternate airport for my flight plan.I made an emergency landing at the closed airport. I had no alternative but to use the long; plowed runway. I had no time to tune to CTAF or contact unicom; so I landed in the blind. Only activity was a plow truck at the far end of the runway; but I had no time or other options. I closed my IFR flight plan with center when crossing the numbers and safe landing was assured. After landing; I contacted unicom.

Original NASA ASRS Text

Title: GA pilot reported landing at a closed airport due to adverse flight characteristics caused by icing.

Narrative: While on IFR Flight Plan to I encountered unforecast icing conditions just north of ZZZ while on vector to the ILS. I immediately requested a 180 turn-out due to icing; toward my departure airport; which was also my filed alternate. Within a couple minutes; there was significant ice accumulation such that there were significant unfavorable flight characteristics. No longer able to maintain altitude; I requested a vector to the nearest airport. A vector was given to ZZZ1. Although ATC did not advise the airport was closed; I already knew it was because I saw the NOTAM previously when I had considered this an alternate airport for my flight plan.I made an emergency landing at the closed airport. I had no alternative but to use the long; plowed runway. I had no time to tune to CTAF or contact UNICOM; so I landed in the blind. Only activity was a plow truck at the far end of the runway; but I had no time or other options. I closed my IFR flight plan with Center when crossing the numbers and safe landing was assured. After landing; I contacted UNICOM.

Data retrieved from NASA's ASRS site 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.