Dear Ms Dawson,
I am writing to apologise sincerely for missing the budget meeting on Tuesday, which I know was important for the whole department.
I had left home in good time, but my train was cancelled because of a signal failure, and the replacement bus was caught in heavy traffic. There was no mobile signal in the tunnel, so I could not warn you until the meeting had started, and I regret that.
To catch up on what I missed, I have already asked Sarah for her notes and I have read the draft figures that were circulated. I would also like to meet you briefly this week to go through any decisions that were made, so that I can complete my part of the work before the deadline on Friday.
Please accept my apologies once again for any inconvenience this has caused. I will leave home earlier in future so that a single delay cannot cause the same problem, and I am ready to take on any extra work you think necessary.
Yours sincerely,
Daniel Wright