Heating Your Greenhouse in Europe This Winter

[Bern]

Heating Your Greenhouse in the USA This Week

A massive system of extremely cold air will affect most the country this week. The extent of this system, as well as the frigid temperatures is something to behold.  Many new record low temperatures will probably occur over the next several days. It will be interesting to see if the electric and natural gas utilities in some areas will be able to keep up with the demand. Some plant people will be sorely vexed by this weather from coast to coast and from the Canadian border to the Gulf of Mexico.  South Florida looks like the only reliably warm spot this week.

Here's the National Weather Service map of the low temps on Tuesday night when the cold mass is at its greatest extent.

[janemcgary]

The map Bern shared is a good graphic for understanding the role of high mountain ranges and maritime wind effects on North America. Right now I'm in the blue-to-green zone at around 20 F in western Oregon, and would not be that cold were it not for the presence of the Columbia River Gorge, cutting the Cascade Range, through which continental winds bring deep, sudden cold. The Pacific coastline is about 120 miles west of us, with its mild winter temperatures in spite of the offshore cold Japan Current. The arctic air mass so prominent on the map is able to extend all the way to the Atlantic coast because there are no continuous high mountains east of the Rocky Mountain range. 

[Bern]

The map Bern shared is a good graphic for understanding the role of high mountain ranges and maritime wind effects on North America.

The Appalachians will block many cold air masses from moving east, but not this one.  Fortunately, the effects of this system will be mild here compared to locations on similar or lower latitudes in the central part of the country.  Rogers, AR, which is even further south than Williamsburg, will experience temps from 0 F to the low single digits for the next few days.  We won't get anything near as cold here.

Interestingly enough, the latest USDA zone map promoted this area from 7b to 8a.  Many other locations across the US received similar promotions.  Will these designations stand if this winter continues to have such cold temps?  Time will tell......

[Martin Bohnet]

OK, now move that cold air east until it hits the atlantic ocean. that will trigger the atlantic trough (that's what LEO spits out for "Tiefdruckrinne", no Idea if that's a thing), and that will drive the cold out of central Europe. That was one hell of a week - frozen hell, I mean...

Seems everyone wants to have the cold air anywhere as long as it's far away. I vote for Russia, they a) are used to it and b) don't deserve it better these days...

[David Pilling]

Going to be a cold few days in the UK - but it will probably stay above 0C here on the coast. Talk is of snow. By the end of the week the weather should start to come from the South-West again and temperatures are predicted to rise to 10C.

[Bern]

In den nächsten Nächten wird es hier bitterkalt sein. Dann wird es nächste Woche wie im Frühling sein!

[janemcgary]

Slowly emerging from an ice storm in the Pacific Northwest. Mark at Illahe (60 miles south of me) reports no collapsed greenhouses, but that happened at other nurseries. I crept out to the bulb house (open sided, solid roof) yesterday and found most foliage looking healthy after 100+ hours below freezing. The horrible Oxalis obtusa that infests the raised beds and comes up through the pot drains, however, looks really dead; probably too much to hope that its zillions of bulblets have died, but at least spring won't look so awful without its foliage there. Snowdrops in the open garden standing up again. Still at least a day before the ice is off my steep road, though.