Narrative:

ATIS at pae was calling the ceiling at 1500 ft overcast. Took off with my student to do lndgs, staying in the pattern. As we took off there was a lower scud layer approaching from the south. On the 2ND takeoff it looked like the layer was approaching pretty fast. On the 3RD takeoff we had to turn an early crosswind to avoid entering the clouds. Completed a full stop landing. I should have discontinued the lesson after the 1ST takeoff since it already looked like the marine layer was rapidly approaching. Felt like I had to fly because my student hasn't flown in a month. After landing we were crossing runway 16L at pae I saw an aircraft fly overhead. I told my student to cross since ground had cleared us to our parking area after exiting runway 16R. That was probably at least 5 mins prior to us crossing runway 16L. (It was a long taxi.) I'm quite sure that we were cleared all the way to our parking area. It was quite early and that is a common clearance when airport traffic is light. I'm hoping we didn't get and miss an amended clearance to hold short or that I misconstrued the original clearance. I was talking to my student, discussing the lndgs he just did. At the very least I should have confirmed with ground that we were cleared to cross.

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Original NASA ASRS Text

Title: PIPER PA28 INSTRUCTOR PLT ENTERED IMC DURING STUDENT TRAINING IN PRACTICE LNDGS AND THEN SUBSEQUENTLY CROSSED A PARALLEL RWY WITHOUT CLRNC DURING TAXI IN.

Narrative: ATIS AT PAE WAS CALLING THE CEILING AT 1500 FT OVCST. TOOK OFF WITH MY STUDENT TO DO LNDGS, STAYING IN THE PATTERN. AS WE TOOK OFF THERE WAS A LOWER SCUD LAYER APCHING FROM THE S. ON THE 2ND TKOF IT LOOKED LIKE THE LAYER WAS APCHING PRETTY FAST. ON THE 3RD TKOF WE HAD TO TURN AN EARLY XWIND TO AVOID ENTERING THE CLOUDS. COMPLETED A FULL STOP LNDG. I SHOULD HAVE DISCONTINUED THE LESSON AFTER THE 1ST TKOF SINCE IT ALREADY LOOKED LIKE THE MARINE LAYER WAS RAPIDLY APCHING. FELT LIKE I HAD TO FLY BECAUSE MY STUDENT HASN'T FLOWN IN A MONTH. AFTER LNDG WE WERE XING RWY 16L AT PAE I SAW AN ACFT FLY OVERHEAD. I TOLD MY STUDENT TO CROSS SINCE GND HAD CLRED US TO OUR PARKING AREA AFTER EXITING RWY 16R. THAT WAS PROBABLY AT LEAST 5 MINS PRIOR TO US XING RWY 16L. (IT WAS A LONG TAXI.) I'M QUITE SURE THAT WE WERE CLRED ALL THE WAY TO OUR PARKING AREA. IT WAS QUITE EARLY AND THAT IS A COMMON CLRNC WHEN ARPT TFC IS LIGHT. I'M HOPING WE DIDN'T GET AND MISS AN AMENDED CLRNC TO HOLD SHORT OR THAT I MISCONSTRUED THE ORIGINAL CLRNC. I WAS TALKING TO MY STUDENT, DISCUSSING THE LNDGS HE JUST DID. AT THE VERY LEAST I SHOULD HAVE CONFIRMED WITH GND THAT WE WERE CLRED TO CROSS.

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.