Sunday, July 8, 2012

88 F. "Cool Front" (on track for hottest summer in U.S. history?)

86 F. high temperature in the Twin Cities Saturday.

84 F. average high for July 7.

87 F. high temperature a year ago; July 7, 2011.

+12.6 F. The first week of July is running more than 12 F. above average at KMSP.

3,215 record highs, nationwide, in June.

64 days above 100 F. in the Twin Cities since 1873. Source: Minnesota Climatology Working Group.

13 counties in northeastern Minnesota declared Federal Disaster Areas. $108 million in damage to public property. Source: Star Tribune.

Not-As-Hot-Front. Expect mid to upper 80s from today into Tuesday, still a few degrees above average for early July. Models pull the mercury back up to near 90 by Thursday, the ECMWF hinting at mid-90s by next weekend.

94 F. average temperature for the entire day, Saturday, at Washington Reagan Airport, averaging all 24 hours.

106 F. for one minute at DCA, Washington Reagan Airport Saturday, tying the all-time record for hottest reading ever observed in our nation's capital. Source: Capital Weather Gang.

"Historically, Minneapolis/St. Paul has experienced an average of 12 days per summer over 90 and less than 2 days over 100. Under the higher-emissions scenario, the Twin Cities could experience nearly 70 days above 90°F toward the end of the century and 28 days over 100. Under the lower-emissions scenario, the Twin Cities would experience a little more than 30 days over 90 and 7 days over 100, on average." - from a recent UCS (Union of Concerned Scientists) press release.

"At some point...extreme weather events will have become sufficiently common to convince any person of reason that global warming has begun." - from a story on climate change by Doug Craig at below.

A Week's Worth Of Records. All those red dots are record highs, yellow dots are record (warm) nighttime lows. Map courtesy of NOAA and Ham Weather.

Most 100-Degree Days Since 1988. Here is a statement from The Minnesota Climatology Working Group: "For the second time in a week, the mercury hit 100 degrees or higher at the Twin Cities International Airport. The last time there were two 100 degree maximum temperatures in the Twin Cities was 1988, when there were four. July 1-6, 2012 will also finish the warmest first six days of July on record in the Twin Cities with a preliminary average of 87 degrees F, higher than the next closest average (July 1-6 1949) with 84.2 degrees F. It's been relatively uncommon to see the mercury reach 100 at the Twin Cities International Airport in recent years. Before 2011, the last time the maximum temperature was 100 degrees or more was on July 31, 2006 when the air temperature reached was 101 degrees. Looking back to 1873, the maximum temperature at the Twin Cities official measuring site has reached 100 or more on 64 occasions. The most was in 1936 with nine days. The last year with more than one 100 degree temperature was in 1988 with four.

Lingering Warm Bias. The 6-10 Day Extended Temperature Outlook from NOAA's Climate Prediction Center (CPC) shows extreme heat spreading into much of the Pacific Northwest, Northern Rockies - more heat aimed at the Dakotas and Minnesota the latter half of this week (but right now I don't see 100 F). We'll have to be content (?) with mid 90s. Hot enough. Map courtesy of Ham Weather.

Dry Spell. A dry week is shaping up for most northern tier states, the best chance of heavy rain and embedded T-storms from Houston and Little Rock to Knoxville, Asheville and the Outer Banks - some 2-5" amounts are possible. QPF map courtesy of NOAA HPC.

The Longest, Hottest Heat Wave. D.C. Records 9th Straight 95+ Day. Some amazing details on the (historic) heat wave from The Washington Post's Capital Weather Gang: "For the 9th straight day, Washington, D.C. has met or exceeded 95 degrees (officially 95 at 11:25 a.m., 96 is the high so far today). In 141 years of records, this is a first. And the streak is likely to be extended to 11 after Saturday and Sunday. This record is just one of countless extraordinary heat records established over the course of the last three summers."

Graphic credit above: "Number of consecutive days at or above 95 degrees in Washington, D.C. since 1872." (Ian Livingston)

From NOAA in Washington D.C.:

"The earliest reported reading of 100 F. in a calendar day was recorded yesterday, July 6, 2012...just before 12 pm noon EDT, or 11 am Eastern Standard Time. Previously the earliest record of a 100 F. reading in Washington D.C. was August 21, 1930 at noon EST, or 1 pm EDT. The most number of consecutive hours of 100 F or better in Washington is 7 hours. This has occurred twice...once on July 21, 1930 from noon to 6 pm EST...the other was yesterday, July 6, 2012 from noon to 6 pm EDT.

From The Capital Weather Gang:

5:40 pm update: The weather observer at National Airport reports the temperature did hit 106 F. for one minute. That would have tied D.C.'s all-time high, but it has to last for at least 3 minutes to count. So today's official high will go down as 105 F, breaking the previous July 7 record of 102 F. in 2010. Also, Dulles tied its record high for the date with a high of 101 F, while BWI broke its record high for the date with a high of 103 F.

8:25 pm update: It's likely we've established at least two additional records today at Reagan National. 1) Highest low temperature for the date of 82, two degrees above the old record of 80 from 2010 (assuming it doesn't drop below that before midnight). 2). Highest average temperature for any calendar day on record (all-time) of 94 F.

Gridlock: Storms, Blackouts Expose Power Problems. Our infrastructure is increasingly vulnerable to blackouts from super-sized thunderstorms, as explained in this NPR article; here's an excerpt: "As hundreds of thousands swelter without power a week after a violent storm pummeled the Midwest and Mid-Atlantic, energy experts say the future will look even worse if the nation's aging, congested electrical grid isn't upgraded. Customers chafe at rising utility bills, but the energy industry warns that the alternative is even scarier: Unless $673 billion is invested in the system, it could break down by 2020, according to an American Society of Civil Engineers report released in April. The grid's dependability has become an increasing concern as the system strains to meet increased demand. Bottlenecks in the grid and equipment failures are causing more brownouts and blackouts, energy experts say."

Photo credit above: Monte Draper/AP. "A power pole is bent after severe storms hit the Bemidji, Minn., area on Tuesday, knocking down thousands of trees and causing extensive damage to utility lines. Thousands of customers were left without power."
Photo Of The Day: "Undulatus Asperatus". Thanks to Paul Schroeder for sending in an amazing example of undulatus asperatus, which is a recently discovered cloud type, an exotic wave cloud formed by extreme turbulence and temperature inversions (temperatures warming with altitude). He snapped this photo near Hayward, Wisconsin Saturday morning.

Cumulonimbus. Thanks to Paul Brooks, a prolific storm chaser, who heads up PBrooks Photography. A link to the photo and his company via Facebook. This shot was taken north of Bennett, Iowa.

Is Your Computer Infected Wit DNS Malware? I know, I was skeptical too (more like paranoid to click on anything I don't know or trust), but this is a legitimate concern, and using the link below you can (safely) check your PC or Mac to see if you're infected.

"Ask Paul". Weather-related Q&A:

Today's highlighted question is a good one: how do we (as meteorologists) grade ourselves? How does "verification" really work? Every meteorologist, to some degree or another, uses their own metrics to evaluate what they believe to be an accurate forecast. If you're withing 2-3 F. of the predicted temperature, that usually fits the definition of an accurate forecast. Precipitation is much trickier, especially in summer. If the forecast calls for "partly sunny with isolated thundershowers" and it doesn't rain at your house, but a town 10 miles away gets dumped on, is that an accurate forecast? All weather is local. Everyone cares about their home, their neighborhood, but during a typical summer afternoon it may only rain on 10-30% of the state.

Mr. Paul Douglas,

"I read your narrative in the StarTribune June 22, 2012 weather column.  You stated that the national accuracy for a 24-hour forecast is 87%.  This prompted me to reach back and read a paper I wrote in Feb 1999 that looked at a small slice of weather data for the previous year.  That paper was written in response to similar accuracy questions I had at the time.  I still have the same questions today.  For instance, what weather variable(s) does the 87% refer to? - high temperatures, low temperatures, humidity (dew factor), sun, wind, rain, etc?.  Under what parameters is the accuracy calculated?

I have attached the paper (Weather.docx) and and some supporting graphs (hi_lo_tm.xlsx) based on the data I collected.  I know you are a very busy man, but I hope you will find time to read the paper and comment on my questions above

Thank You,
Warren Banks

Warren - thanks for your note and the work you put into the white paper/spread sheet. The 87% number is the generally agreed upon metric for 24 hour accuracy (averaging all forecasts, NOAA and private sector). I can't find a paper or link to support that number, but I've heard it batted around now for nearly 30 years - and (interestingly) ithat 87% number hasn't improved during that period, in spite of (significant) gains for Day 2-7. I forwarded your question to the local NWS office in Chanhassen and here is their response:

"We use a few different methods internally to try and gauge our accuracy. The forecasters look at verification information frequently, since it is tough to improve if one doesn't know how well he/she is doing. Plus, we view detailed verification of the various model guidance, since knowing what is working best makes it easier for us to do well, since we can work from the "best" starting point. The majority of our verification is now done in a gridded manner, such that we verify things at each 2.5x2.5 km. grid box for which we produce a forecast (for the National Digital Forecast Database). The "truth" which we verify against is a combination of the Real-Time Mesoscale Analysis (RTMA) combined with all available observations (METARS, mesonet data, etc). 

In the past, verification was only done for specific points, and could be misleading on how the overall forecasts were performing across the entire area. For temperatures, a common metro we use to judge our accuracy is the measure of the percentage of the entire forecast area (evaluated at each grid point) for which the error is <3 degrees F. As an example, over the past 30 days, our forecasts (MPX) for our area for low temperature the following night (i.e. the forecast issued today for tomorrow night) have had an overall error of <3 degrees F for 70.1% of the area, with 0% having an error >10 F. 

For the day seven forecast, over the past 30 days, the area with error of <3 F was 34.2% and the error of >10 degrees F was 11.7% These are just quick examples, but should give you some idea of things we commonly look at to quickly assess our accuracy with respect to temperatures. For the probability of precipitation, the thing we consider most frequently is the "reliability" metric, which essentially provides information on what percenage of the time a given probability occurs. Perfectly calibrated POP's would result in a situation when measurable precipitation occurs 20% of the time that 20% POPs are forecast, 50% of the time 50% POPs are forecast, and 100% of the time 100% POPs are forecast."

Tom Hulquist, NOAA (Twin Cities office)

Experimental Headlight Can See Through Rain And Snow. I thought this story from was interesting; here's an excerpt: "Driving at night in falling rain or snow can be treacherous, but not just because the asphalt is slippery – visibility is also greatly reduced, as the driver’s view of the road ahead is obscured by brightly headlight-lit raindrops or snowflakes. In the future, however, that may not be so much of a problem. A team led by Carnegie Mellon University’s Prof. Srinivasa Narasimhan has developed an experimental headlight system that renders most foreground precipitation virtually invisible, while still adequately illuminating the road beyond."

Forget The Ice Cream Truck, This One Makes Wood-Fired Pizzas! This might work in....California? Details from "Del Popolo’s is a traveling pizza truck located in San Francisco, that features an impressive wood-fired pizza oven. The mobile restaurant has been constructed from a recycled shipping container which has been completely remodeled to include a modern kitchen workspace and two large glass doors that open out to the public."

Is Your Computer Infected? I know - it sounds like one of those scams you DON'T want to click on, but this is legit. According to the FBI there is a lot of malware out there that may prevent hundreds of thousands of Internet users from accessing the web on Monday. To see if your computer is infected click here (I did it with my PC - no problems). It's a little additional peace of mind on a Sunday. Service provided by (Thanks Pete!)

Great Story-Telling Advice (From A Pixar Pro). Here's an excerpt of a terrific story about...storytelling, from an employee of a company that has turned it into a true artform, Pixar - from the Wall Street Journal (subscription may be required): "For the past five years, Pixar has served as my film school. As a storyboard artist, working mainly on "Brave" but more recently on other projects, I had the privilege to collaborate with an incredible creative team. As we hashed out the details of our narrative, I learned a lot about the basics of storytelling, and I have used Twitter to share them with others. Here's some of what I've road-tested from my work trying to bring Princess Merida, other Pixar characters and my own creations to life. 

1. You admire characters more for trying than for their successes.
2. Remember that what's interesting to an audience can be very different from what's fun to do as a writer."

19 Thoughts About Finding Your Purpose. I found this simple - yet profound. Here's an excerpt from

"Those who win are producers, not consumers. The first thing you do each morning should be active, not passive– no Facebook, no email. Whatever you choose should put you in a state of mind for the rest of the day. Choose carefully.

The goals others set for you are usually wrong. The people who give them to you seem well meaning, and they have more experience, too. But your heart will guide you better than anyone. Find internal markers to know if what you’re doing is right.

If you do two things at once, one of them is getting done wrong. No matter how wrong you think this is, or how many exceptions you think there are… I sincerely doubt it."

Mea Culpa. Yes, the weather was nicer than expected yesterday - but nobody seemed to mind too much. I've made the startling discovery that people tend not to mind (much) if the weather turns out nicer than predicted, but woe is ye if it's the other way around. In spite of morning clouds and a few showers over southern Minnesota skies cleared rapidly, with a welcome drop and temperature. How did 86 qualify as a "cool front" anyway? Over half an inch of rain fell from storms overnight in the metro; Saturday highs ranging from 81 at Grand Marais to 86 at St. Cloud and the Twin Cities.

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

TODAY: Plenty of warm sun - slight chance of an isolated shower up north late. Winds: NW 10-15. High: 88

SUNDAY NIGHT: Partly cloudy. Low: 64

MONDAY: Sunny, pleasant breeze. Dew point: 58. High: 85

TUESDAY: Warm sun, still dry. Dew point: 59. Low: 63. High: 86

WEDNESDAY: Hazy-blue sky, warmer. Low: 65. High: 88

THURSDAY: Partly sunny, sticky again. Dew point: 65. Low: 68. High: near 90

FRIDAY: Intervals of hazy sun, humid. Dew point: 68. Low: 70. High: 92

SATURDAY: Partly sunny and hot. Lake-worthy. Dew point: 70. Low: 72. High: 95

A Summer to Remember

This is the summer where 85 F became a "cool front".

Even some of my most skeptical friends are beginning to have second thoughts about a warming atmosphere. They may not believe peer-reviewed papers from climate scientists but they tend to believe their own eyes.

How do you separate day to day changes in weather from longer term climate trends? The sky overhead is running a low-grade fever, and we can diagnose the symptoms: at least 240 ALL TIME record highs in just the last 2 weeks, 2,346 record highs in the last week, record low Arctic ice, 7 times more record highs than record lows since January 1. 2012 will probably be the warmest year ever recorded. The previous records: 2010 (warmest) and 2011 (second warmest). Coming after the warmest winter.

The pace of records seems to be accelerating.

I sense we're only seeing the tip of the iceberg; a chronic, low-grade climate emergency that will turbocharge droughts, spike rainfall rates, and take our breath away.

The climate scientists were right.

A stray T-shower may pop later today up north, but this week looks unusually dry - no widespread, organized showers or T-storms are in sight through the end of the week. 90 F returns by Thursday; maybe mid-90s by next weekend?

Welcome to a long, hot summer.

October anyone?

* photo credit above:

Climate Stories....

Cartoon Credit: "This Pat Bagley editorial cartoon appears in The Salt Lake Tribune on Sunday, July 8, 2012."

What Global Warming Looks Like. Here's part 2 of a thoughtful 4 part series on our recent spate of extreme weather and a link with climate change, from Doug Craig at "Seth Borenstein, an Associated Press writer, published a piece on Independence Day with this lead: "If you want a glimpse of some of the worst of global warming, scientists suggest taking a look at U.S. weather in recent weeks." He also wrote, "These are the kinds of extremes climate scientists have predicted will come with climate change, although it's far too early to say that is the cause. Nor will they say global warming is the reason 3,215 daily high temperature records were set in the month of June." But look it this way. If you are making soup, you can make it without salt or with a little or a lot of salt. Each decision will affect the taste. Human activity is to our climate like salt is to soup. Once you add salt and mix it in, every spoonful contains a little of that extra flavor. Same with our climate. We have added enough extra CO2 and methane and various other greenhouse gases to permanently alter the Earth's atmosphere. Every inch of sky bears our brand."

Union of Concerned Scientist Press Release. Here is a press release from The Union of Concerned Scientists that arrived Friday. I was going to provide an excerpt, but this is too important to chop up and edit. So I'm including the entire statement from UCS:

Heat waves and climate change
As heat-trapping emissions from burning coal and gas and destroying tropical forests continue to pile up in the atmosphere, the Earth’s average temperature increases and with it, the likelihood that extreme heat events will occur.

Over the last decade, the United States has set twice as many record highs as record lows. Because warmer air can hold more moisture, heat indices, which measure what it actually feels like to be outside, are also increasing. Meanwhile, the number of extreme heat events globally has increased and in the United States, there has been an increase in high-humidity heat waves characterized by high nighttime temperatures.

Cities are particularly vulnerable to extreme heat, in part, because dark, heat-absorbing asphalt and heat-trapping buildings are so prevalent. Over the past fifty years, smaller cities have seen extreme heat events increase by an average of almost six days per year, while larger cities have seen an increase of about 15 days.

Future projections of extreme heat nationally
According to a U.S. government scientific assessment, dramatically reducing emissions would limit average warming in the United States to between 4 and 7 degrees Fahrenheit by the end of the century. But staying on a business as usual path would lock in 7 to 11 degrees of warming. The assessment projected that staying on our current path would make extreme heat events that occurred just once every twenty years in the past happen every other year or annually throughout the country by the end of the century.

Over the very long term, higher temperatures could make it very difficult, if not impossible, for people to tolerate the outdoor heat during the hottest months of the years in many parts of the world. The emissions choices we make today will determine whether or not such scenarios will remain on the table.

Extreme heat is an economic and public health threat
People’s health is most at risk from basic heat stress, which can result in hospitalizations and death. Extreme heat is also a catalyst for increased ground-level ozone pollution -- or smog -- which can cause breathing problems and exacerbate asthma.

Heat also can drive spikes in energy demand as people crank up their air conditioners. During the 2011 heat wave, peak power prices in affected areas jumped from $100 per megawatt hour to $350. Such increases translate to hefty electricity bills for consumers. Additionally, heat stresses electricity grids, lowering their efficiency and increasing equipment failures.

When it comes to agriculture, extreme heat can dampen productivity for crops and cattle. Extreme heat can drag down yields for corn, soybean, wheat and cotton. For livestock, extreme heat can sap milk production as much as fifty percent, lower the rate at which livestock gain weight, and greatly reduce reproduction rates.

North America was hit hard in 2011, with the kind of heat wave that is more likely in a changing climate

For the United States, 2011 was the hottest summer since the Dust Bowl. Forty-two states had above-normal temperatures for the summer months and 4 states broke records for extreme summer heat. During a July heat wave, the National Weather Service had issued heat alerts for areas home to approximately 141 million people.

The National Climatic Data Center estimates that the combination of heat, wildfires and drought in the Southwest and Southern Plains resulted in $12 billion worth of damage, including damage to agricultural and livestock production.

Preparing for a future of heat stress
Americans can build resilience to climate change consequences and take aggressive measures to reduce our carbon emissions and the risks of climate change. Because a certain amount of climate change is already locked in for the next few decades, we will have to cope with the impacts of extreme heat on our daily lives, our health and on our economy. Preventative public health measures and local preparedness are critical for protecting public health and saving lives. But in order to effectively prepare for the impacts of climate change, we need a comprehensive national strategy to create climate-resilient communities and reduce the emissions that are driving climate change.

Extreme heat projections for select Midwest States and Cities
Confronting Climate Change in the U.S. Midwest, a 2009 UCS analysis, included heat projections for nine Midwest cities based on two future emissions scenarios. The analysis also included projections for how the summer-time climates of two states – Illinois and Michigan – would “migrate.” Below are summaries of that information and links to relevant charts and graphics.

By the end of the century, under a lower-emissions scenario Illinois’s summer-time climate is projected to be more like Arkansas and Louisiana’s while under a higher-emissions scenario it would more closely resemble Texas. Illinois “migrating state” map.

By the end of the century, under a lower-emissions scenario, Michigan’s summer-time climate is projected to resemble Tennessee, Missouri and Arkansas’ climate. Under a higher-emissions scenario, it would be more like Oklahoma’s. Michigan “migrating state” map.

Historically, Chicago has experienced an average of 15 days per summer over 90 and about 2 days per year over 100. Under the higher-emissions scenario, Chicago could experience more than 70 days above 90°F toward the end of the century and 30 days over 100. Under the lower-emissions scenario, the city would experience less than 40 days over 90 and 8 days over 100, on average.

Historically, Cincinnati has experienced an aver­age of more than 18 days per summer with highs over 90 and less than 2 days over 100. Under the higher-emissions scenario, Cincinnati is projected to experience more than 85 days over 90°F—nearly the entire summer—and 29 days over 100 by the end of the century. Under the lower-emissions scenario, Cincinnati would experience less than 50 days over 90 and 8 days over 100, on average.

Historically, Cleveland has experienced an aver­age of 9 days per summer with highs over 90 and less than 1 day over 100. Under the higher-emissions scenario, Cleveland is projected to experience more than 60 days over 90 and 21 days over 100. Under the lower-emissions scenario, Cleveland would experience less than 30 days over 90 and 5 days over 100, on average.

Des Moines:
Historically, Des Moines has experienced an average of 22 days per summer over 90 and less than 2 days over 100. Under the higher-emissions scenario, Des Moines could experience more than 85 days above 90°F toward the end of the century and more than 30 days over 100. Under the lower-emissions scenario, the city would experience less than 50 days over 90 and only 9 days over 100, on average.

Historically, Detroit has experienced an average of 10 days per summer over 90 and less than 1 day over 100. Under the higher-emissions scenario, Detroit could experience almost 65 days per summer with highs above 90°F toward the end of the century and 23 days above 100. Under the lower emissions scenario, the city would experience less than 30 days above 90 and 5 days over 100, on average.

Historically, Indianapolis has experienced an average of 17 days per summer over 90 and less than 1 day over 100. Under the higher-emissions scenario, Indianapolis could experience over 80 days above 90°F toward the end of the century and 28 days over 100. Under the lower-emissions scenario, the city would experience 40 days over 90 and 7 days over 100, on average.

Historically, Milwaukee has experienced an average of 9 days per summer over 90 and less than 1 day per year over 100. Under the higher-emissions scenario, Milwaukee could experience more than 55 days per summer with highs above 90°F toward the end of the century and 22 days over 100. Under the lower-emissions scenario, the city would experience less than 30 days over 90 and 5 days over 100, on average.

Minneapolis/St. Paul:
Historically, Minneapolis/St. Paul has experienced an average of 12 days per summer over 90 and less than 2 days over 100. Under the higher-emissions scenario, the Twin Cities could experience nearly 70 days above 90°F toward the end of the century and 28 days over 100. Under the lower-emissions scenario, the Twin Cities would experience a little more than 30 days over 90 and 7 days over 100, on average.

St. Louis:
Historically, St. Louis has experienced an average of 36 days per summer above 90 degrees and less than 3 days over 100. Under the higher-emissions scenario, St. Louis could experience 105 days above 90°F toward the end of the century and 43 days above 100. Under the lower-emissions scenario, the city would experience a little more than 60 days over 90 and 11 days over 100, on average.

Aaron Huertas
Press Secretary, Union of Concerned Scientists
Washington D.C.

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