Tuesday, September 21, 2010

Flood Watch (and a new summer record for MSP)

* Severe storm watch southwestern and south central MN until 6 pm today.

* Clouds roll in today, heavy rain likely from this evening through much of Thursday, latest models printing out 2-3" for the Twin Cities, a "tropical rain" likely (more typical of June than September).

* Flood watch issued by the NWS for much of Minnesota from tonight into Friday morning.

* Unsettled Saturday - passing shower or two possible, temperatures holding in the 60s.

* Sunday still looks like the sunnier, milder day, chance of sampling low to mid 70s.

* 8-14 Day Outlook keeps Minnesota significantly milder than normal through the first week of October.

* New summertime record for the Twin Cities: nighttime lows for June, July and August were the warmest ever recorded, nearly 5 degrees F. warmer than "average."

Severe Storm Watch. SPC has issued a watch for southwestern and south central MN until 6 pm - it does NOT include the immediate MSP metro area. Hail, damaging winds, even an isolated tornado can't be ruled out.

Flood Watch. Yes, it's going to rain - a LOT of rain on tap. The watch is in effect from Wednesday night through Friday morning for some 2-4" rainfall amounts (heavier north metro). If you live in a flood-prone region take all necessary precautions.

Gulley-Gushing, Window-Rattling Rain?
The latest NAM/WRF model prints out 2.65" of rain for the Twin Cities by Thursday evening. Some 2-4" amounts may set up over parts of central MN (looks like the north metro could see as much as TWICE as much rain as the south metro). Watering optional until further notice.

Biggest Pumpkin In The World? Attention Charlie Brown - we just found your mythical Great Pumpkin, weighing in at 974 pounds in a field near Bluefield, West Virginia. The eye-opening video from WAVY-TV here.

Record-Setting Summer. Monday's official high came close to midnight (80 degrees) and it got me thinking about summer warmth, specifically how unusually warm the nights were. According to Pete Boulay at the MN State Climate Office the average low temperature from June through August was 65.4 F, which is the warmest on record. The old record: 65.1 F in 1939. By the way, the average nighttime low for June - August is 60.5 F, so we were almost a full 5 degrees warmer than average. Amazing.

Warmest Average Summertime Nighttime Lows. Data from June 1 through August 31, according to Pete Boulay at the MN State Climate office.

A Wet And Worrisome Flood Outlook for Minnesota. The Star Tribune's Bill McAuliffe reports on a growing sense of concern across northwestern Minnesota about the potential for spring flooding in 2011. The ground is saturated from recent heavy rains, river and lake levels high - locals worried that if heavy snows fall on top of waterlogged ground the result may be the third year in a row of record flooding in the Red River Valley. More on the wet weather concerns here.

Soggy 60-Day Spell. The map above shows "departure from normal" since July 21, the last 60 days, indicating that much of central and western Minnesota (the dark blue regions) has seen 1.5 to 2 times as much rain as typical. Portions of the north metro have been a little bit drier than average - drought conditions lingering over the MN Arrowhead.

Study Seeks To Explain The Parting Of The Red Sea. Disclaimer: I do not believe everything can be explained by science (I happen to believe that miracles are possible - I've seen them in my own life and the lives of others). That said - I stumbled upon this article that tries to provide a meteorological explanation for what Moses may have encountered some 3,000 years ago, documented in the Book of Exodus. Hmmm.

Tropical Storm Lisa. So far in 2010: 14 tropical depressions - 12 of those grew to tropical storm strength, 6 went on to become full-fledged hurricanes with sustained winds higher than 74 mph. "Lisa" is still out in the eastern Atlantic, NASA is using a low-orbiting satellite with a special "AIRS" sensor, the Atmospheric Infrared Sounder, which measures the temperatures of clouds. In the last 24 hours the tops of thunderstorms near the center of the storm cooled (to -94 F), hinting at additional intensification - in all probability Lisa will become the 7th named hurricane of the season. More from NASA here.

Hey, It's NOT a Toy! Have an iPad? Want to bring back fond, carefree memories of your childhood? Now you can have the best of both worlds - an Etch-A-Sketch iPad case has just been released, details from neatorama.com here.

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

Today: Some sun early, then increasing clouds - rain possible by late afternoon/evening. Wind: East 10-20. High: 67

Wednesday night: Cloudy with rain likely, heavy at times. Low: 59

Thursday: Rain, heavy at times - a few T-storms possible (some 1-3" amounts possible). High: 72

Friday: Windy and cooler with more clouds than sun - drying out (dry for evening football games). High: 65

Saturday: Still unsettled, more clouds than sun with a passing shower possible. High: 66

Sunday: Much better. Probably the nicer day, plenty of sun, breezy and mild by afternoon. High: 73

Monday: Blue sky, still lukewarm. High: 74

Tuesday: Clouds increase - slight chance of a shower or sprinkle late. High: 69

What a strange September we're muddling through. I was pretty pumped up in late August, anticipating a mostly-sunny, mostly-dry September with a spell of lukewarm days, and a rapid drop-off in thunderstorms. We should be worrying about foggy mornings, tracking hurricanes in the Atlantic and Caribbean - instead we're tracking significant storms every 2-3 days, still tormented by bouts of severe weather. Burnsville picked up quarter-size (1" diameter) hail late Monday night, right after the metro area experienced a high of 80 close to midnight. What the heck is going on here?

We salvaged a good-looking Tuesday with a welcome dip in humidity - no weather complaints yesterday. Expect a dry commute this morning, but any fleeting sun will get snuffed out by increasing clouds by midday, a good chance that rain may streak into town by late afternoon or evening. Not sure about after-school activities later today - odds favor some rain after 4 or 5 pm. That rain may fall (heavy at times) tonight into a portion of Thursday - some of the computer models still printing out some 1-3" rainfall amounts for the metro area by Thursday evening, even a band of 3-5" from near St. Cloud and Monticello into the far northern suburbs of the Twin Cities. If that verifies we may have some minor flooding problems across parts of central MN by tomorrow, some swollen streams, wet basements, flooded intersections. That's typical of June, but September?

What strikes me about the summer of '10? A couple of things: humidity levels significantly higher than long-term normals. 145 tornadoes, Minnesota still leading the nation in that unlikely count, and a warmer than normal summer than lead to a much greater consumption of electricity to keep us cool. Based on "cooling degree days" we spent an estimated 35% more money than usual cooling our homes and businesses than normal. Where we're really seeing much of the warming (during the summer as well as the winter) is in the observed nighttime lows. As I mentioned up top nighttime lows in the Twin Cities during June, July and August ran almost 5 degrees F. warmer than average. The reason? Consistently higher dew points, more moisture in the air (the temperature can't fall below the dew point). If you have a day where the dew point is 70 you limit how cool it can get during the nighttime hours. More moisture in the air also provides more potential fuel for severe storms, flash flooding, hail and tornadoes. According to Pete Boulay at the MN Climate Office we had 252 hours of dew points > 70 F. this summer - that's 80 hours more than usual! Yes, it was an unusually sticky summer - that kept us warmer at night (and stormier than average, whatever "average" is these days).

So a pouring, soaking rain is expected from tonight into much of Thursday, maybe an inch or two for the metro, with some 2-4" amounts not out of the question across central Minnesota. A wind shift to the northwest on the backside of this area of low pressure begins to punch a few sunny holes in our stale cloud deck Friday - we begin to dry out, but scrappy stratocumulus clouds may linger much of the day (although I expect dry weather for Friday evening football games).

The weekend outlook? A bit more muddled than it was yesterday, I'm afraid. Models are hinting at a cold wrinkle of air drifting over Minnesota Saturday (one of those 'dang-blasted "upper air disturbances" that increasingly torment us during the fall months). If the sun is out for a few hours Saturday morning (likely) the airmass overhead may become unstable enough for a few instability clouds, even a passing shower or two Saturday afternoon. It won't rain all day - it should NOT be as runny & muddy as tomorrow - but a 20-30 minute shower can't be ruled out Saturday afternoon. By Sunday this cold twist aloft pinwheels over the Great Lakes, a warming trend aloft promising a more stable atmosphere floating overhead. That should mean more sun, enough blue sky for low to mid 70s across much of Minnesota with a light southwest breeze. Sunday should be a classic September day across the state - without a doubt the nicer day of the weekend.

We can't (officially) call it Indian Summer - yet. The reason? Most of central and southern Minnesota has yet to experience the first killing frost of the season. Up north locals can safely call it Indian Summer, without reproach or some weather know-it-all gently correcting you. North of Brainerd and Mille Lacs most areas HAVE seen the first frost, even the first killing freeze with a few hours colder than 28 up on the Iron Range.

Sunny, mild (dry) weather should spill over into Monday, possibly Tuesday, before the next clipper-like system whips up a few showers or sprinkles late Tuesday.

The foulest day in sight: Thursday. No redeeming qualities whatsoever, at least weatherwise. the best day in sight? Sunday. Blue sky, low humidity, highs topping 70s across most of central and southern Minnesota. By Monday a few towns south and west of the MN River may approach 80. That's more like it. Hey, the 8-14 Day Extended Outlook from the Climate Prediction Center has us considerably warmer than average through the first week of October.

Hope springs eternal...

Igor's Aftermath. Newfoundland, Canada has been getting a serious thrashing, courtesy of "Igor", which has weakened into an (intense) extra-tropical low pressure system, still capable of 5-10" rains. At least 20,000 residents of the Burin Peninsula were cut off from the rest of Newfoundland - airports closed, a number of roads washed out from torrential, tropical rains. USA Today has the latest here.

Newfoundland Flooding. Hurricanes hitting Canada? Rare, but not unprecedented. Click here to see what can happen when 5"+ rain in less than 24 hours.

8 Costliest Hurricanes On Record. We've been very lucky so far this year (we're up to the "L-storm" - Lisa just formed in the eastern Atlantic), and yet the United States has yet to suffer a direct strike so far in 2010. #1 on the list: Katrina, which triggered an estimated $125 billion dollars worth of damage along the Gulf coast in 2005. For a rundown of the 8 most expensive hurricanes in U.S. history click here.

Typhoon Fanapi. Taiwan is cleaning up from a damaging typhoon (same thing as a hurricane, but they're called "typhoons" in the western Pacific, "cyclones" in the Indian Ocean, sometimes referred to as "Willy Willys" off the coast of Australia). As much as 44" of rain was reported in southern Taiwan - at least 2 deaths blamed on the typhoon - damage estimated at least $62 million and rising. It was the 11th typhoon to hit China so far this year - more from the AP here.

Warm Spell? September temperatures are running 2 degrees F. cooler than average. We're due for a warming trend and it appears to be imminent. The CPC, the Climate Prediction Center, shows a high probability of warmer than average weather for the Upper Midwest, the Rockies and Southwestern USA through October 5. We'll see a run of 70s, I certainly wouldn't rule out another 80-degree high close to home.

"Global Climate Disruption." The administration is (apparently) concerned that the term "global warming" is too benign, implying a gradual, uniform buildup of greenhouse gases. They are suggesting that we transition to using the expression "global climate disruption". Top White House Science Advisor John Holdren "changes to the climate are rapid, when viewed in terms of the capacity of society and ecosystems to adjust, the impact is distributed unevenly, and the outcome will be overwhelmingly negative for much of the globe." More from the New York Times here.

Climate Change: Are Private-Public Partnerships The Answer? Can private capital investment coupled with federal funding (and various incentives) be the answer that propels green-tech to the next level? An interesting story from the Wall Street Journal here.

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