I'd take her out to lunch and start some gossip. Sort of like "Did you hear we're going to lose our jobs?". Then move on to I heard that XXxx is on the short list and I might be too. If she says "NO! I heard we're all going to be fine" then you need to sort of say "Well I heard you and I are both on the top of the list for being let go".
By saying your job is at risk too, even if it's not, won't make her feel like it's personal. By starting this "gossip" it's not XX told me you are getting fired when they start shifting stuff around, you better get prepared. It's giving her a heads up that lots of jobs are at risk.
My hubby was working at a local electric co-op as a computer guy for a few years. He made a good living. They had a credit union and we had little debt.
We both bought program vehicles. They were nice cars and our car payments were just over $700 per month. Our car insurance on these vehicles was just over $1100 every 6 months. We were still able to pay our bills and have money left over for our needs. We didn't have any kids living with us, my daughter lived full time with her dad. Raising my grand kids didn't happen until years later.
Anyway. We had just bought hubbies car and thought his job was pretty secure. They laid him off the week before Christmas....
They sent him a letter in January from the credit union that we either needed to pay off both cars by the end of the month or forfeit them to be sold at auction. We would of course be liable for any money remaining on the note if they didn't sell for what we owed on them.
They came and got them. They sued us for the remaining couple of thousand dollars we owed them when it was all said and done but hubby health had started to deteriorate and he was unable to work full time. They garnished his wages at 15% for a long time to get their money.
Had we known they were thinking of outsourcing their IT support we might not have bought such expensive vehicles, mine was not as expensive as his anyway.... It would have been nice to know it "might" happen so we could start planning to minimize our spending. Not that we spent lots of money each month but we might have been able to put hubby's car up for sale and paid it off. My car would have been low enough payments that would could have probably kept it.
As it was we had no car, our house, credit cards, everything was gone. He had been laid off at his long time job a year or so before this and we had just started getting on our financial feet again. We never recouped our financial stability.
We lost everything.
So having any sort of idea he might lose his job would have been a life changing bit of information. Even if it had just been "gossip between friends" it would have put that little bit of doubt in our mind/on the back burner. So it some major purchase was possible we might have chosen to wait until the job cuts were done.
By saying it's gossip you're not putting anyone on the defensive you are putting it as something hidden and secret, that makes her interested. That it's special information. It's not so "Hey, you're getting fired".
By including yourself in the possible lay offs she doesn't feel alone and things you are a co-worker who is in the same boat, soon to be out of a job.
By saying you've heard this through the grapevine she feels special because you chose to share it with her. It's like a rallying of the work force, all being in the same position to lose their jobs. It helps her accept what you're saying and makes her feel like she's not alone.