OP's question was when it was "appropriate" to ask and the answer to that is that it can never hurt. But, the 2-hour scheduled connection was a sellable connection well over MCT and agents who do fee-free changes these days do get asked to justify their change fee waivers, especially, as here, where there is a carrier change to BA (yes, I understand that both are OW and that some routes are under a JV).

There is also a tendency to push these things off to the connection point as aircraft make up time enroute and connecting flights get delayed. In this situation, unless the LAX flight was overbooked and at risk of oversale, there is real revenue on the table.

On the other hand, this was a departure from the EU and EC 261/2004 delay/cancellation compensation would have applied. It would have been measured at OP's final ticketed destination, e.g. DEN. I have no idea what a misconnect at LAX would have meant, but if it had pushed the DEN arrival back sufficiently, that would have cost AA EUR 600.

I would try everything. Ask at the AC, call, and as a last resort at the gate. Don't bother if you have checked luggage as this was a connection from VIE and the chances that AA would manually pull luggage for a voluntary change at the gate were slim.

It's time for winter type weather and disruptions, and today there are ground holds at LGA for high winds and delays at EWR for traffic volume. See links in the Wikipost to learn more.

Weather waiver for ORD and much of the midwest due to a winter storm. Currently applies to travel December 10 or 11.

Winter Storm Caly - Midwest U.S.
Information current as of December 9, 2016

If you’re traveling to/through/from:

Chicago, Illinois (ORD)
Detroit, Michigan (DTW)
Flint, Michigan (FNT)
Grand Rapids, Michigan (GRR)
Kalamazoo, Michigan (AZO)
Lansing, Michigan (LAN)
Marquette, Michigan (MQT)
Traverse City, Michigan (TVC)
Cleveland, Ohio (CLE)
Toledo, Ohio (TOL)
Green Bay, Wisconsin (GRB)
Madison, Wisconsin (MSN)
Milwaukee, Wisconsin (MKE)

The change fee may be waived if you:

Are traveling on an American Airlines flight
Bought your ticket by December 8, 2016
Are scheduled to travel December 10 - 11, 2016
Can travel December 09 - 13, 2016
Don't change your origin or destination city
Rebook in same class or pay the difference
Look up your trip and see if you have the ‘change trip’ button to change it online.

Travel Alert - Winter Storm Decima
 

Just got an email.

Winter Storm Decima
Information current as of December 15, 2016

If you’re traveling to/through/from:

Chicago, Illinois (ORD)
Fort Wayne, Indiana (FWA)
Indianapolis, Indiana (IND)
Detroit, Michigan (DTW)
Flint, Michigan (FNT)
Grand Rapids, Michigan (GRR)
Kalamazoo, Michigan (AZO)
Lansing, Michigan (LAN)
Marquette, Michigan (MQT)
Traverse City, Michigan (TVC)
Minneapolis, Minnesota (MSP)
Buffalo, New York (BUF)
Rochester, New York (ROC)
Syracuse, New York (SYR)
Erie, Pennsylvania (ERI)
Pittsburgh, Pennsylvania (PIT)
Akron, Ohio (CAK)
Cleveland, Ohio (CLE)
Columbus, Ohio (CMH)
Dayton, Ohio (DAY)
Toledo, Ohio (TOL)
Toronto, Ontario Canada (YYZ)
Sioux Falls, South Dakota (FSD)
Green Bay, Wisconsin (GRB)
Madison, Wisconsin (MSN)
Milwaukee, Wisconsin (MKE)
Mosinee, Wisconsin (CWA)
The change fee may be waived if you:

Are traveling on an American Airlines
Bought your ticket by December 15, 2016
Are scheduled to travel December 16 - 17, 2016
Can travel December 15 - 20, 2016
Don't change your origin or destination city
Rebook in same class or pay the difference
Look up your trip to see if you have the ‘change trip’ button to change it online.

Question - would I just be able to cancel for a refund? The rules don't make it seem that way.

Doubt it. Rules only allow for rebooking - only in same class. You'll have to have your flight to cancel for a refund. (And depending on your departure city, some may start canceling later today...)

Its ORD-LAS tomorrow at 5:05. I was never planning on taking the flight, I was just hoping to luck out and get my money back without a change fee.

Strong Headwinds! (BOS-LAX/PHX)
 

Headwinds are really strong right now! Head up if your flying BOS-West Coast.

AA305 (6pm BOS-LAX) stopped in ORD (presumably fuel) and others have flying times of 7+ hours!

https://www.flightradar24.com/data/flights/vx367
https://www.flightradar24.com/data/flights/aa305

VX, UA & DL have all stopped today in MCI!

Make sure you have plenty of time if making connections in LA!

EF confirms it was a fuel stop. There have been lots of fuel stops on westbound transcons this week for airlines that operate the 320 on those routes (B6, VX, etc). I think this is the first I am hearing of a 738 stopping (though it may have happened other times)

A bit late to the party, but AA has posted a Northeast Travel Waiver for December 17-18.

Winter Storm Decima - Northeast U.S.
Information current as of December 16, 2016

If you’re traveling to/through/from:

Wilkes-Barre/Scranton, PA (AVP)
Hartford/Springfield/Windsor Locks, CT (BDL)
Baltimore, Maryland (BWI)
Boston, Massachusetts (BOS)
Portland, Maine (PWM)
Manchester, New Hampshire (MHT)
Newark, New Jersey (EWR)
Albany, New York (ALB)
Buffalo, New York (BUF)
Islip, New York (ISP)
Ithaca, New York (ITH)
Johnson City, New York (BGM)
New York Kennedy, New York (JFK)
New York La Guardia, New York (LGA)
Rochester, New York (ROC)
Syracuse, New York (SYR)
Watertown, New York ()
White Plains/Westchester, New York (HPN)
Allentown, Pennsylvania (ABE)
Harrisburg, Pennsylvania (MDT)
Philadelphia, Pennsylvania (PHL)
State College, Pennsylvania (SCE)
Providence, Rhode Island (PVD)
Burlington, Vermont (BTV)
Washington Dulles, Washington DC (IAD)
Washington Reagan National, Washington DC (DCA)
The change fee may be waived if you:

Are traveling on an American Airlines
Bought your ticket by December 16, 2016
Are scheduled to travel December 17 - 18, 2016
Can travel December 16 - 22, 2016
Don't change your origin or destination city
Rebook in same class or pay the difference
Look up your trip to see if you have the ‘change trip’ button to change it online.

In case my flight tomorrow is cancelled from ORD
 

perhaps the best option is to try to catch up to my cruise in Nassau on Monday. Is it within my "rights" to ask for a confirmed seat on flights to Nassau as it is within 300 miles of my planned destination? I was told by the reservations agent who gave me my one free change that if the new flight is cancelled, I could standby for any flight within that distance. But that may be limited to the US. Any experts here? Trying to work out a backup plan. Open to other suggestions. The ship sails on Sunday at 4.

Most importantly, in the future, never, ever fly to a cruise on the day of departure. Under any circumstance.

Pretty clear she's flying tomorrow and cruise is not until Sunday.

Flight Delays & Bad Weather
 

I hoping someone can help give me some advice. My wife and I are traveling to Punta Arenas in a week and a half leaving from Chicago.

I had booked the flight with my AA miles to Santiago (SCL) and on a separate LATAM ticket from SCL to Punta Arena (PUQ). My total flights looked like this:

* ORD (6AM Dec 29th) -> DFW
* SCL (7:40PM Dec 29th) -> SCL (7AM Dec 30th)
* SCL (8AM Dec 31st) -> PUQ

I gave us 12+ hours in DFW to account for any winter weather delays out of ORD, and a full day in SCL to account for any delays getting out of DFW. However, American has since changed our itinerary and their schedule so it is now:

* ORD (3PM Dec 29th) -> DFW (5:40PM)
* SCL (7:40PM Dec 29th) -> SCL (7AM Dec 30th)

So now if we are delayed out of ORD for more than 2 hours we will miss our SCL flight. The SCL flight now runs once a day which means we would miss our SCL->PUQ flight and since they are on separate tickets I would be out of luck and the rest of our LATAM legs would be canceled and would strand us in Santiago.

I called American Airlines and explained my situation and asked that they either change my flight back to my original itinerary (I still don't know why they changed our 6AM flight to 3PM..) or get us out of Chicago the day before (Dec 28th). They said there was nothing they could do since I'm an award ticket and that I should call back closer to my departure if the weather looks unfavorable.

Now my question for you all is if it looks like there will be snow or ice for my departure day (Dec 29th) when should I call American Airlines and try again to get them to adjust our outbound flight? If there is a weather advisory do they typically let you depart before the storm hits or is it typically only to reschedule for after the inclement weather passes? Any other suggestions on how to handle a possible delay or bad weather next week would be great. Thanks!

Call AA back and say u don't accept their re accommodation to the later ORD DFW flight. Happens all the time. Should be simple to fix. Sounds like this is sometyoe of Skd change. Now, if u previously accepted it, then u might have a problem. Also, u might have to escalate to a supervisor. AA can open up award space on their metal for Skd changes

Agree. Whenever the computer plays with a reservation for any reason - one minute schedule change, equip chg, flt number chg - it will often grab flights with shorter connections. The 6:00 AM is still operating - should not be a big deal to get back on it.