Not very autumnal

Yesterday, at precisely 4:18 pm central time, the sun's direct rays passed over the equator, marking the autumnal equinox, the official kick-off of the Fall of '09. In reality autumn really began closer to September 1, when "meteorological summer" came to an end. Climatologists tracking the warmest 90 day period, the balmiest 3 months, admit that summer REALLY kicks off June 1 and goes through September 1. I guess we've just been living a lie these last 3+ weeks, although I have to say that September has been more memorable, more lake-worthy and tempting, than just about anything I can recall back in July and August. Yes, it was a "Manitoba Summer", the edge came off the heat. Many Minnesotans were just fine with Summer Lite, but a significant percentage of friends, family and colleagues felt irritated, CHEATED that we never had any true Dog Day weather, you know: week after week of hot, stuffy, steamy, unbearable weather. Speaking of cheated, residents of Minneapolis/St. Paul are wondering what happened to the showers that looked like such a sure thing on Monday. Crystal picked up .13" of rain, .12" at Flying Cloud Airport in Eden Prairie, and yet the airport (MSP International) saw only a trace of rain. Same at St. Paul: a trace! The story of the month.

Last month Chaska picked up 10" of rain. So far this month: about 1/10th of an inch. That's 1/100th the amount that fell just 30 days ago. What gives? Whoever is playing with the atmospheric thermostat please stop! We can't take too much more of this...


July was cool, August was wet (one of the 10 wettest on record) and now September: the driest in recent decades, and one of the warmest too. Temperatures are averaging 5-7 degrees above normal, a trend which may just linger through the end of the month. With generous sunshine returning again today we should see some mid 70s, 80 is not out of the question again Thursday as Minnesota finds itself "between storms". One cut-off low doing the twist over the central Plains (capable of dumping 6-16" of snow west of Denver by midweek above 9,000 feet). That area of low pressure will eventually open up and lift northeastward, increasing the chance for rain here by Friday and Saturday. Check out the computer simulation below: the latest run keeps most of the rain to our east, over Wisconsin, on Saturday, with leftover clouds and a few light showers or sprinkles for Minnesota (it does not look as wet as yesterday's run).



In between Storms. Madison, WI picked up close to 4" of rain on Tuesday, a 24 hour rainfall record. Meanwhile a stalled storm "cut off" from the main jet stream, swirling over the central Plains, may dump over 10" of snow near Aspen by Thursday...a potentially early start to the ski season west of Denver this weekend. That storm to our southwest will approach later in the week, increasing the potential for the first significant rain of September by Friday and Saturday.

Although shirtsleeves, sunglasses and short reign supreme the next couple of days (if you can get away with it) have a jacket handy for Sunday and Monday of next week. A surge of chilly air jabs south of the border - by Sunday evening it will be cold enough for flurries over Lake Superior's North Shore. Monday looks gusty and foul with wind-whipped showers and sprinkles, winds puffing away at over 30 mph, temperatures holding in the 50s over much of Minnesota. A rapid warming is set for next week; we will see more 60s, probably another run of 70s toward the very end of September and the first week of October. Nothing wintry in sight (yet) but by Sunday we'll all get a definite taste of autumn. Yes, we are due for a.....taste.

Paul's Outlook for the Twin Cities

Today: Partly cloudy and mild. Winds: NE 5-10. High: 75

Tonight: Mostly clear and cool. Low: 53

Thursday: Warm sunshine, still feels like late August. High: near 80

Friday: More clouds, a few showers, possible thunder. High: 76

Saturday: Lingering clouds, unsettled. Little more than a light shower or sprinkle. High: 72

Sunday: Better chance of showers, turning windy and cooler. High: 66 (falling during the PM)

Monday: Feels like autumn (finally!) Mostly cloudy, gusty, cool with showers/sprinkles. High: 58

Tuesday: Less wind, more sun, not as uncomfortable. High: 63

Wednesday: Sunny, breezy, turning milder again. High: 72

GFS Model Output valid Saturday evening at 7 pm. The map shows rainfall in the 12 hour period from 7 am to 7 pm Saturday, showing the brunt of the shower activity to our east in Wisconsin and northern Illinois. A showery, unsettled weekend is likely; another surge of showers arriving Sunday with a vigorous cool front that will have us reaching for jackets early next week.

Back to normal on the sun? It's not much: one lonely sunspot, but after the fewest sunspots on the sun in nearly a century astronomers are observing more sunspots coming into view. A handful of climatologists are linking this lack of sunspots to cool weather over North America this past summer - a return to normal (ie. more sunspots) could mean a return to milder conditions yearround. Time will tell. For more information click here and read up more at spaceweather.com.