Sorry naive out-of-towner,
There is virtually no chance of a tailwind here as prevailing storms are always from the WEST. The 1987 CIM was run in horrible heavy rain with recorded 75 mph HEADWINDS on the ground and 125 mph aloft!
I have run NYC, Boston, Chicago, London, and Berlin and IMHO BERLIN is THE super fast and "record quality" course it deserves to be.
CIM is really a "crap shoot" in terms of a "fast course" as about 20% of the time there is a storm front and a HEADWIND. Yes, when the conditions are neutral, like 2017 and 2018, it is a good PR course, but as noted, it is NOT FLAT and it is ROLLING. There is also a little uphill at around 21-22 miles for the bridge over the American River.
CIM this year was SUPER FAST for everybody behind the two top finisher males as there were PACKS OF RUNNERS from place 3 on back who stayed together for almost ALL THE RACE! Here are some depth stats:
265 Women broke 3 hours
662 Men were under 3 hours
139 women were under 2:50 (NYC Marathon, 18 American)
433 total (men + women) under 2:45
61 men broke 2:20 (NYC Marathon, 8 American)
50th place woman was well under 2:43 !
This was THE BEST SHOWING of American men in terms of depth of field under 2:20 since about the 1984 Boston Marathon and it is absolutely THE BEST SHOWING overall depth of field for American Women (50th place time) perhaps EVER!