I've seen this "airline notes" field on flight information displays on Travelocity - here's an example URL:

http://dps1.travelocity.com/dparflif...UA&flt_num=251

I did some searches, but can't find out how to decode the notes, which look like this:

ETD .30L LTEQ/1245CT/1345-2000/PROB DLYS/DVRT/CNCL-THUNDERSTORMS+ETA .43L LTEQ+

They seem to differ from airline to airline (these are from United). Anyone in the know on how to decode United's?

It looks similar to a METAR. I can definitely decode part of that - reported at 12:45 Central Time (1245CT), effective 13:45 - 20:00 (1345-2000), probable (PROB) delays (DLYS), diversions (DVRT), and cancellations (CNCL) due to thunderstorms (THUNDERSTORMS). I might also hazard a guess that estimated times of departure (ETD) are 0.30 hours late (.30L) and estimated times of arrival (ETA) are 0.43 hours late (.43L), but those are only guesses. I have no idea what LTEQ might mean.

Edited to add: Actually, the .30 and .43 are not fractions of an hour, but minutes (30 minutes and 43 minutes).

ETD .30L = Estimated Time of Departure is 30 minutes late

LTEQ/1245CT/1345-2000/PROB DLYS/DVRT/CNCL-THUNDERSTORMS = Not sure on this one, perhaps late arriving equipment due to delayed/diverted/cancelled flights due to thunderstorms

+ETA .43L = Estiamted Time of Arrival is 43 minutes late

LTEQ+ = Again not sure other than late arriving equipment

united.com says schedule change due to late arriving aircraft.

Actually you may be correct, it could be .30 hours and .43 hours based on what united.com is showing 6:05 scheduled departure/6:19 estimated departure and 8:33pm scheduled arriveal/9pm scheduled departure.

Wirelessly posted (BlackBerry7290/4.0.0 Profile/MIDP-2.0 Configuration/CLDC-1.1 UP.Link/6.3.0.0.0)

Yeah I think .43 refers to the mins.

it changed to:

OUT .20L RAMP/1245CT/1345-2000/PROB DLYS/DVRT/CNCL-THUNDERSTORMS+ETA .28L RAMP+

Based on the previous posts / united.com, I'm guessing that the flight left 20 minutes late due to "ramp" ( ramp service? ). The weather thing still seems a concern, and the flight is expected 28 minutes late. Am I getting this right?

Yes.

hamburgler

It's pretty much a straight pull from our flight following information command (FLIFO). When we pull it up, it's displayed a little bit better, something like this: (note this isn't a real display, I pulled information from a few flights to make an example that shows everything)

F:251/27MAY
IAD/1723CT/OFF 623P .04L RAMP
PDX/1723CT/ETA 819P .14E RAMP
IAD/1245CT/1345-2000/PROB DLYS/DVRT/CNCL-THUNDERSTORMS

The first line tells you how many minutes late (L) or early (E) the flight is/was/expected to be, and the delay reason. RAMP would show up as "Ramp Service" on United.com or on the easyInfo displays at the gate. Other examples:
CUST - Customer Service
FACL - Facilities
ARPT - Airport Operations
WX - Weather
ATC - Air Traffic Control
MECH - Aircraft Servicing

The final line refers to what calls up in our command as a "DPAM", or advisories for an airport that is either the arrival/destination/stopover point of the flight number.

Happy Travels!