THINK wine from the USA and you’ll think California. It’s hardly surprising – more than 90% of all wine made in the USA is Californian.

Of the rest, the wines of the ‘Pacific Northwest’ are the best. Washington State is the most important producer, followed by Oregon, its southern neighbour. Idaho makes some wine too, but its three dozen wineries are dwarfed by the 700 of Washington and almost 400 of Oregon.

Commercial viticulture began in earnest in Washington and Oregon in the 1960s. The wine soon gained a reputation for high quality, often in a more delicate and aromatic style than that produced in California.

In particular, Oregon turned out such upper-class Pinot Noir that even leading winemaking companies from Burgundy were keen to buy land and get in on the act.

Pinot Noir is still Oregon’s speciality. It takes up nearly two-thirds of the state’s vineyard. It is very good indeed, but expensive.

Some growers are worried that their high production costs will price them out of a competitive market. Top-class Oregon Pinot Noir is a luxury product and sales to cash-strapped American consumers have fallen.

Oregon’s climate is relatively cool and damp. Most vineyards lie in the Willamette Valley, south of Portland and to the west of the Cascade Mountains. Across the Columbia River, almost all the vineyards of Washington State are planted in the Columbia Valley, to the east of the Cascades and in their rain shadow.

Here the climate is very different, with baking summers, freezing winters, very low rainfall and abundant sunshine.

The growing season is lengthened a little by the huge range in temperature between day and night, even in midsummer. Such conditions make it possible to make flavourful wines with both high sugar levels and crisp acidity.

The vines are planted on the warmest south-facing slopes, not to encourage them to ripen as fully as possible, but to mitigate the worst of the winter cold.

Pinot Noir does not respond well to the rigours of the Washington weather. The favoured grapes there are Cabernet Sauvignon, Chardonnay, Merlot and Syrah, but rather against the odds, Riesling is very popular too.

Despite a constant murmur of critical acclaim and prices that have fallen to reasonable levels for all but the best Oregon Pinot Noir, not much wine from the Pacific Northwest has found its way to our shops (my wine of the week is a welcome exception).

And as opportunities to taste it are accordingly fairly infrequent, I leaped at the chance to make amends at the annual Washington and Oregon trade tasting held in London a few weeks ago. I wanted to judge for myself just how good these wines really are.

I was duly impressed by some of the Oregon Pinot Noirs, though they were not all as elegant as I’d hoped, and I was very pleasantly surprised by Washington State Riesling and in particular the suggestively named Snoqualmie Naked Riesling.

It’s ‘naked’ because it’s organic, though Oregon outdoes Washington in the rush to be crowned the queen of sustainability. It can now boast that a third of all its vineyards are managed organically. Nowhere else in the world is quite that green. The Snoqualmie wine has a lovely classic balance between sweetness and tangy acidity and like much Riesling grown in a rather warm place, is markedly mineral.

To buy it you’ll have to go online to www.oldbutcherwinecellar.co.uk where it costs £11.75.

The same shop, linked to one of the main importers of Washington and Oregon wine into the UK, has one of the very best choices of goodies from several wineries, including a fine and relatively affordable Oregon Pinot Noir (for a special occasion) in the form of Erath Vineyards Oregon Pinot Noir 2008 (£17.99).

If that sounds a bit steep, just think how much a halfway decent red Burgundy will set you back. I also warmly recommend Domaine Sainte Michelle Blanc de Noirs (£12.50), a carefully-crafted fizz from Washington State with deliciously fresh, crunchy strawberry fruit.

And amongst those rich red wines balanced by juicy acidity that Washington does increasingly well, Snoqualmie’s cheapest Syrah, a nicely mature 2006 (£11.75), is a very good, affordable example.

Another good source online is www.savageselection.co.uk, which I promise is nothing to do with me!

They are fine wine merchants based in Cheltenham. They list, for example, Eyrie Vineyards’ excellent Oregon Pinot Noir and even a couple of wines from Idaho.

Pinot Gris, not often one of my favourite grapes, was another welcome surprise both from Oregon, where it plays second fiddle only to its cousin Pinot Noir, and from Washington State.

Château Sainte Michelle Pinot Gris 2008 is very good and is available locally from Rehills of Jesmond – so often a source of unusual and worthwhile bottles. It costs just £9.99.

For this you get a deliciously smoky dry white with quince apple and melon and lots of gingery spice.

Other local merchants will be delighted to get hold of Pacific Northwest wines if you ask for them. Carruthers & Kent, for example, have told me that they are happy to do so.

WINE EXTRAS

Pinot Noir and Sauvignon Blanc thrive in the relatively cool climate of South Australia’s Adelaide Hills.

Nepenthe’s Altitude series wines are good examples. They have just released new vintages. Sauvignon Blanc 2010 (£8.49) from Waitrose, Majestic or the Co-op has an invitingly grassy, passion fruit and green pepper smell and a crisp, zesty, yet ripely fruity, almost peachy taste.

Pinot Noir 2008 (£9.99 at Majestic or the Co-op) has a big, spicy cherry and raspberry aroma and a juicy, red fruits taste, balanced by quite firm tannins.

Viñalba Gran Reserva Malbec 2008 (£13.99 at Majestic) is a very grand red indeed and shows how complex and sophisticated Argentine Malbec can be in the right, careful hands.

Big, rich and spicy with layers of lingering plum and damson fruit, it manages to be elegant despite 14.5% alcohol. Very impressive.

WINE OF THE WEEK

Château Sainte Michelle, Cabernet Sauvignon, 2005 £12.99, Rehills of Jesmond

This mature yet still youthful red is a great advert for Washington State, with a lovely depth of ripe blackcurrant and licorice fruit, an overlay of leather and spice and a lingering, slightly salty aftertaste. An excellent partner for roast beef – rare, of course.