THE PLT RPRTD HE ENCTRD IFR CONDS AT APRX 400' AGL DRG TAKEOFF. HE ELECTED TO 'FLY OUT OF IT' & 'WAS IN THE CLEAR' AFTERCLBG TO 4500' MSL. HE ELECTED TO RETURN TO THE ARPT & INDCD HE COULD SEE THE ARPT 'ON AND OFF' THRU BRKN CLDS. ON AN APCH TO LND, THE ACFT WAS 'IN & OUT OF IFR.' AS THE PLT WAS FLARING TO LND, THE ACFT WAS BLOWN OFF THE CENTERLINE, SO HE ELECTED TO GO ARND. HE APPLIED FULL PWR, BUT AFTER RAISING THE FLAPS, THE ACFT STRUCK THE GND BESIDE THE RWY. THE PLTSTATED THE ACDNT WAS AT 0830, BUT POLICE RPRTD IT OCCURRED AT 0300. THE PLT RPRTD A 400' CEILING & 5 MI VIS WITH FOG; 18 MI NW AT THE MIDWAY ARPT, THE WX WAS IN PART: 20,000' OVC, 6 MI VIS WITH HAZE, WND 190 DEG AT 10 KTS. AT 0950, BLOOD SAMPLES TAKEN AT A HOSPITAL SHOWED THE PLT HAD AN ALCOHOL LVL OF 0.04%. ASSUMING ALCOHOL WAS METABOLIZED AT 0.015% PER HR, HIS BLOOD/ALCOHOL LVL AT 0300 WOULD HAVE BEEN APRX 0.14%. THERE WAS NO INDCN OF ALCOHOL CONSUMPTION AFTER THE ACDNT.MARAJUANA METABOLITES WERE FND IN HIS URINE, BUT NONE WERE FND IN HIS BLOOD. HE HAD NO NGT FLTS IN THE PREVIOUS 90 DAYS.