This hospice site says that dying has two phases. Preactive usually is up to two weeks. Active is 3 days.

Preactive symptoms Mom has had:

increased periods of sleep, lethargy (5 weeks)

decreased intake of food and liquids (3 weeks)

inability to heal or recover from wounds or infections (2 weeks)

increased swelling (edema) of either the extremities or the entire body (2 weeks)

Active symptoms Mom has had:

inability to arouse patient at all (coma) or, ability to only arouse patient with great effort but patient quickly returns to severely unresponsive state (since Sunday, 7/11)

inability to swallow any fluids at all or not taking any food by mouth voluntarily (today, 7/17)

patient breathing through wide open mouth continuously and no longer can speak even if awake (since Sunday, 7/11)

blood pressure dropping dramatically from patient’s normal blood pressure range–more than a 20 or 30 point drop (at least since Thursday, 7/15)

marked decrease in urine output and darkening color of urine or very abnormal colors, such as red or brown (Today it is brown, like dark tea. 7/17)

patient’s body is held in rigid unchanging position (since at least last Thursday, July 8 )

About.com has different signals. They are similar in some ways. I am only noting the ones that I didn’t see on the last one.

One to two weeks prior

The blood pressure lowers. (Friday, 7/16)

There is increased perspiration. (Friday, 7/16)

Speaking decreases and eventually stops altogether. (This has been happening since ICU, at least. I wasn’t here before. So, July 1.)

Days to Hours
None of these match Mother.