Narrative:

Pae ATIS indicated 1200' AGL ceiling and VFR visibilities at the time of my departure at am PDT. I was cleared for takeoff on 16R, make a right downwind departure northbound. I was cleared for 1200' MSL to remain VFR below the clouds. On the downwind, as I was approaching mukilteo, the clouds became less distinct and the ceiling and visibility declined rapidly. I descended as soon as possible to about 800' to maintain VFR, also making a turn of about 20 degrees right to avoid a cloud. About 3-4 mi north of pae I noticed a business jet about 400-500' above me, apparently inbound to pae. No evasive action was necessary; however, he did complain to pae tower of the presence of a light plane on the localizer. I was VFR at about 800-900' MSL, and he was in and out of scattered to broken clouds above. I indicated to the tower that I had the traffic in sight. She chastised me for crossing the localizer west/O notifying her and that I should do so in the future. I reported my position at that time as just east of hat island. Notes and contributing factors: ATIS at pae did not indicate the much lower ceiling and visibility north of the field. Pae tower did not inform me of the inbound jet traffic. Due to the rapid decline of cloud height and visibility I was unable to maintain reference behind me to note the position for the runway centerline extension. Subsequent pilot report from another aircraft showed the ceiling to be less than 1300' MSL in the control zone (that's 700' AGL) pae. I would suggest that pae use either 16L or 34R for all light plane (under 250 hp) departures when VFR is either marginal or instrument approachs are being made to the instrument runway--as a way of keeping VFR/IFR well separated. I was assigned 16R, even though 16L was also in use. (I did not request a change to 16L, however offer this as a suggestion.)

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Original NASA ASRS Text

Title: SMA DEPARTING VFR ENCOUNTERS LOWERING CEILINGS. TURNS TO AVOID CLOUDS AND CROSSES LOCALIZER APCH COURSE. NMAC WITH BUSINESS JET.

Narrative: PAE ATIS INDICATED 1200' AGL CEILING AND VFR VISIBILITIES AT THE TIME OF MY DEP AT AM PDT. I WAS CLRED FOR TKOF ON 16R, MAKE A RIGHT DOWNWIND DEP NBND. I WAS CLRED FOR 1200' MSL TO REMAIN VFR BELOW THE CLOUDS. ON THE DOWNWIND, AS I WAS APCHING MUKILTEO, THE CLOUDS BECAME LESS DISTINCT AND THE CEILING AND VISIBILITY DECLINED RAPIDLY. I DSNDED ASAP TO ABOUT 800' TO MAINTAIN VFR, ALSO MAKING A TURN OF ABOUT 20 DEGS RIGHT TO AVOID A CLOUD. ABOUT 3-4 MI N OF PAE I NOTICED A BUSINESS JET ABOUT 400-500' ABOVE ME, APPARENTLY INBOUND TO PAE. NO EVASIVE ACTION WAS NECESSARY; HOWEVER, HE DID COMPLAIN TO PAE TWR OF THE PRESENCE OF A LIGHT PLANE ON THE LOC. I WAS VFR AT ABOUT 800-900' MSL, AND HE WAS IN AND OUT OF SCATTERED TO BROKEN CLOUDS ABOVE. I INDICATED TO THE TWR THAT I HAD THE TFC IN SIGHT. SHE CHASTISED ME FOR XING THE LOC W/O NOTIFYING HER AND THAT I SHOULD DO SO IN THE FUTURE. I RPTED MY POS AT THAT TIME AS JUST E OF HAT ISLAND. NOTES AND CONTRIBUTING FACTORS: ATIS AT PAE DID NOT INDICATE THE MUCH LOWER CEILING AND VISIBILITY N OF THE FIELD. PAE TWR DID NOT INFORM ME OF THE INBOUND JET TFC. DUE TO THE RAPID DECLINE OF CLOUD HEIGHT AND VISIBILITY I WAS UNABLE TO MAINTAIN REF BEHIND ME TO NOTE THE POS FOR THE RWY CENTERLINE EXTENSION. SUBSEQUENT PLT RPT FROM ANOTHER ACFT SHOWED THE CEILING TO BE LESS THAN 1300' MSL IN THE CTL ZONE (THAT'S 700' AGL) PAE. I WOULD SUGGEST THAT PAE USE EITHER 16L OR 34R FOR ALL LIGHT PLANE (UNDER 250 HP) DEPS WHEN VFR IS EITHER MARGINAL OR INSTRUMENT APCHS ARE BEING MADE TO THE INSTRUMENT RWY--AS A WAY OF KEEPING VFR/IFR WELL SEPARATED. I WAS ASSIGNED 16R, EVEN THOUGH 16L WAS ALSO IN USE. (I DID NOT REQUEST A CHANGE TO 16L, HOWEVER OFFER THIS AS A SUGGESTION.)

Data retrieved from NASA's ASRS site as of August 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.