Friday, February 26, 2010

An abnormally Quiet Pattern for Minnesota

I'll admit it: I'm very, very nervous. No real storms within a thousand miles of quiet a late February as I can recall in recent years. I'm quickly running out of ways to say "sunny & quiet." Lately Minnesota has resembled a cold Palm Springs, day after day of blue sky, gentle breezes and low humidity. O.K. The golfing is still pretty rough, but you get my drift. We're coming up on 2 weeks in a row without a "plowable" snow. An unusually persistent bubble of high pressure anchored - stalled over the Upper Midwest is responsible for our blue-sky weather winning streak. Under the center of that fair-weather system: light winds and occasional inversions, resulting in a few days with rare midwinter air pollution advisories for the Twin Cities. Wait, New York City is getting steamrolled with snow and we're getting....smog? I know, very odd.

Can I tell your weather-fortune?
There are no atmospheric "gotcha's" in the 7-Day, at least not yet. We expect a fair amount of sunshine today, again Sunday, daytime highs close to freezing. A slight cooling trend by the middle of next week gives way to another warming trend by the first weekend of March, highs may reach the mid 30s within a week or so. Hardly grilling weather, but a baby-step in the right direction.

Snowy Hurricane. OK. OK. I realize it's not even close to being a true hurricane, a warm weather/water phenomenon. But the spiral bands of windswept snow wrapping around the center of this temporarily stalled super-storm do create an uncanny resemblance to a tropical system. This Doppler image was recorded Friday morning, when the center of low pressure was almost directly over New York City.

Feeling even better about living in Minnesota. In the next few days I'd like to encourage you to call up a friend living in the Mid Atlantic Region, preferably greater New York. The Big Apple picked up 15-20" of snow from Friday's storm. A good overview on the storm is here. Why so much? Normally storms clip along at 20-40 mph this time of year, limiting just how long it can snow at any given point. But this storm became "cut-off" from the prevailing steering winds aloft. The result: a nearly stationary whirlpool of bitter air aloft, counterclockwise winds pumping a long fetch of Atlantic moisture (like a firehose) directly into New England, New Jersey and parts of Pennsylvania. What would have otherwise been an 18-24 hour snow turned into a 48 hour snow blitz. As of Friday night 36" of snow had fallen so far in February, setting a record for the snowiest month on record. That's more than 3 times more snow than has fallen on the Twin Cities, btw. We feel their pain. Or do we?

Photos Encouraged. Yes, we want to see your weather-related photos. And please try to use your digital camera properly, in stark contrast to the unfortunate woman in the above photograph. Mom, is that you?

Don't let anyone from D.C. or New York City give you a hard time about living in Minnesota. At least not this winter. Many cities and suburbs from Washington D.C. and Baltimore to Philadelphia and New York have seen 2 to 3 times more snow than we have so far this winter. My observations over time (learned the hard way, believe me): the weather has an uncanny way of evening the score. Unusually dry, quiet spells are usually followed by spells of unusually stormy, wet weather. With that in mind, I firmly expect the other shoe (boot) to drop on our heads the latter half of March. We WILL make up for lost time, it's just a statistical inevitability. Looking at the numbers we SHOULD pick up another 10-20" of snow before the rains arrive, wash the drifts away, before thoughts turn to the Twins and the Fishing Opener. The difference? A snowfall in December/January has the permanence of freshly-poured concrete. It won't go anywhere for a good long time! But snow in March often melts within a couple of days of when it falls. The sun is too high in the sky for snow to stick around nearly as long as it does early in the year, when the sun angle is low. Forecast: more snow. And more important: accelerated melting in March and beyond. For the sake of Minnesotans living along rivers my hope is that it's a nice, gradual thaw (without heavy rain). Time will tell...

Everyone is asking why. Why has Dallas seen a little over an inch less snow this month than MSP? Why is D.C. and New York getting creamed while we look on, feeling a little smug about our nagging streak of sunny days? Good question. As I mention in Saturday's print column proving cause and effect with the atmosphere is problematic. But the winter we're experiencing is very consistent with the moderate El Nino, the warming of Pacific Ocean water, that seems to have a cascading domino effect on weather patterns thousands of miles downwind. I've noticed that, during El Nino patterns, the jet stream, the main highway for storms, is much more prone to becoming temporarily "locked" in a pattern that guides Pacific storms into Dixie, and then right up the east coast, detouring many hundreds of miles south of Minnesota, leaving much of the Midwest and Great Lakes area high and dry. El Nino winters tend to be wetter and much cooler for the south and east, but significantly warmer and drier for the northern tier states. So far we are enjoying (?) a warmer than average winter; based on NWS heating degree data we've saved about 5% heating our homes and businesses so far this winter. Snowfall is running close to average for the Twin Cities, a little above average south/west of the Minnesota River (and along the North Shore of Lake Superior) but below average across a big swath of central and northern Minnesota. The St. Cloud area has seen 10" less snow than the Twin Cities. Meanwhile Rochester is boasting closer to 52", with over 60" for Des Moines, again, closer to the non-stop parade of storms sliding off well to our south. Strange, but consistent with the El Nino phenomenon as we understand it. Keep in mind, even though El Nino events have been showing up in the Pacific every 4-8 years, they've only come to the forefront of scientific inquiry (and public attention) since the severe El Nino of 1983, the intense warming of Pacific Ocean water that really put this phenomena on the map.

Rogue Iceberg. Almost 40 miles long, weighing an estimated 700 billion tons, Antarctica's Mertz Glacier Tongue is probably not the result of climate change, at least not directly, but rather the result of a collision with another iceberg. For the complete story click here.

* Be glad your name isn't Al Nino. During the '83 event a resident of Los Angeles by the name of Al Nino received a rash of annoying, threatening phone calls. L.A. experienced a series of major storms, floods, mudslides, even a few rare tornadoes. The locals were upset with the horrific winter weather, and a few called to pin the blame on poor, defenseless Al Nino. There's a guy in need of a name change.

* Snowfall so far in February for the Twin Cities: 13.9" (average Feb. snowfall: 7.3")
* Snowfall so far this winter season at MSP: 40.7" (average snowfall to date: 41.4")

Average snowfall for January (now the snowiest month of the year) is over 10". Why the dip in February? Well, there are 3 fewer days in February than January, and that makes a pretty big difference, statistically. At some point that energized, sopping-wet storm track plaguing the south will shift north with the rising sun. My hunch is that we'll make up for lost ground (and snow) by the middle and end of March. Just an educated guess at this point, a gut feel. Nausea, perhaps?

Faulty Temperature Sensors? Climate scientists rely on observations from satellites (since about 1970), ocean buoys and thousands of land-based weather stations around the planet. Although the NCDC separates out about 120 of these stations in the USA for long-term climate analysis (because they are thought to be far enough away from the warm taint of major urban areas) there is growing concern about the data integrity and reliability of some of these sensors. The complete story at Fox News is here.

Cherry-picking the data to support the content that global temperatures have dropped since 1998? It's disingenuous at best, because 1998 was a major El Nino year, possibly the strongest warming of Pacific Ocean water ever observed. Removing the spurious El Nino years and solar cycles shows a steady upward temperature trend over the last 30 years, a time when greenhouse gases have spiked by 16% An interesting editorial here.

Paul's Conservation MN Outlook for the Twin Cities and all of Minnesota.

Today: Generous sunshine, PM temperatures close to average. Winds: NW 5-10. High: 33

Saturday night: Partly cloudy, still dry, still quiet. Low: 10

Sunday: Partly sunny, more high clouds. High: 33

Monday: More clouds, a few passing flurries possible (from the stalled New England storm!) Low: 16. High: 28

Tuesday: Partly sunny, a bit cooler. Low: 12. High: 27

Wednesday: Mostly sunny and brisk. Low: 15. High: 29

Thursday: Sun dimmed by increasing clouds. Low: 16. High: 31

Friday: Mostly cloudy, flurries possible late, noticeably milder. Low: 18. High: 34

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