Hello, and thank you all in advance for the help.

I would like to know the most accurate translation for "Northwest" and "Pacific Northwest" for a tattoo. Followup: What is the difference between "iarthar" and "siar" with regard to "west"?

Also, I would like to take the translation then re-translate it to Ogham. I was led to believe that you can (starting from the bottom up) translate letters directly from Irish to Ogham using resources online. Is this accurate?

Again, thank you all for your time. Cheers!

the Northwest: an tIarthuaisceart
Pacific Northwest: Iarthuaisceart an Aigéin Chiúin (But this means rather the northwest of the Pacific Ocean itself than an area in the US)
so better: an tIarthuaisceart Ciúin-Aigéanach

iarthar is a noun, an t-iarthar = the west.
siar is an adverb. It means "to the west, westwards"
There's aniar ("from the west"), thiar ("in the west") and laistiar de ("western of ..."), too.

As well, iarthuaisceart is a noun, an t-iarthuaisceart = the northwest (lit. "the westnorth").
The adverbs are siar ó thuaidh ("to the northwest"), aniar aduaidh ("from the northwest"), thiar thuaidh ("in the northwest"), laistiar lastuaidh de ("situated northwestern of ...")

Not really, no. Ogham was based on sounds, not letters. Most of those sites should be taken with a big grain of salt.

Redwolf

Thank you Labhrás and Redwolf -- much appreciated! I will pass on this information! Any tips on finding an accurate way to translate to Ogham that don't need to be taken with a salt lick?