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Paul Douglas on Weather

Another Nice Day Thursday - Highs Around 80 By Friday

Fire Weather Concerns This Afternoon

Due to gusty winds and low humidity values expected this afternoon, a Red Flag Warning has been issued for western Minnesota. This means that conditions are favorable for any fires that develop to rapidly spread.

Winds are expected to gust in the 20-35 mph range across parts of western and southern Minnesota during the afternoon hours.


80 Degrees Possible On Friday

Ready to enjoy some August weather in the second half of October? It is on its way to parts of the state Friday, with highs in the 70s and potentially touching 80 in areas on Friday! The forecast high right now for the Twin Cities Friday is 80.

That high of 80 expected Friday in the Twin Cities will actually approach the record for the day of 83 set back in 1953.

In many areas of the state, highs will be 15-25 degrees above average on Friday. This will certainly be some nice weather for the second half of October across the region... especially when we could have snow falling instead!

If the Twin Cities did hit 80 on Friday, it would be one of the latest last 80s on record as only ten other years have had a later date that the last 80 occurred on. The last average 80 on record (looking over the entire Twin Cities record) occurs on September 29th. Meanwhile, it was quite a warm Halloween in 1950 as that is the date of the latest 80 on record. Last year, the last 80 was on September 18th. The last time we saw a high that was 80 or higher this year was back on September 24th when the high reached 90.


Weather That Makes the Chamber of Commerce Proud
By Paul Douglas

If only this could last, right? Embrace and memorize the good times - power through the bad. Factoring dew point, bug count and allergy index you could make a strong case that the next 2 days will feature some of the finest weather of the year. 80F is not out of the question Friday afternoon; the average high on August 21.

Unusual but hardly unprecedented. On this date in 2000 the mercury hit 84F in the Twin Cities and 90F at Appleton. But the pendulum can just as easily swing in the opposite direction. On October 19, 1972 the mercury sank to 9F in Luverne and St. Peter.

Shorts on Friday give way to umbrellas Saturday as an eastbound cool front sparks a few showers and thundershowers. Sunday will be the sunnier, drier, better day of the weekend for outdoor plans.

A quick swipe of chilly air Tuesday gives way to a stronger, deeper push of Canadian air late next week. The first widespread frost/freeze of the season is likely late next week; possibly the first flurries of the winter season.

When the weather is this nice, for this long, expect the other shoe (boot) to drop!


Extended Twin Cities Forecast

THURSDAY: Sunny and beautiful. High 73. Low 53. Chance of precipitation 0%. Wind S 8-13 mph.
FRIDAY: Sunny with a warm wind. High 79. Low 60. Chance of precipitation 10%. Wind S 15-25 mph.
SATURDAY: Few showers and thundershowers. High 71. Low 47. Chance of precipitation 70%. Wind S 10-20 mph.
SUNDAY: Partly sunny, nicer day of the weekend. High 63. Low 50. Chance of precipitation 10%. Winds W 8-13 mph.
MONDAY: More clouds, few light showers. High 60. Low 43. Chance of precipitation 40%. Winds NW 10-15 mph.
TUESDAY: Cool sunshine, light jackets return. High 53. Low 38. Chance of precipitation 10%. Winds NW 10-15 mph.
WEDNESDAY: Partly sunny, trending milder. High 60. Low 37. Chance of precipitation 10%. Winds SW 8-13 mph.


This Day in Weather History
October 19th

2000: The warmest October 19th in Minnesota history occurs for many towns. Many cities had highs in the 80s, with the Twin Cities hitting 84. Appleton in Swift County reported 90 degrees.

1972: A cold snap moves through Minnesota, with lows of 1 above in Tower and 9 in St. Peter and Luverne.

1916: Redwood Falls receives a record-setting 7 inches of snow.


Average Temperatures & Precipitation for Minneapolis
October 19th

Average High: 57F (Record: 87F set in 2000)
Average Low: 39F (Record: 15F set in 1972)
Average Precipitation: 0.07" (Record: 2.75" set in 1934)


Sunrise/Sunset Times for Minneapolis
October 19th

Sunrise: 7:34 AM
Sunset: 6:20 PM

*Length Of Day: 10 hours, 46 minutes and 27 seconds
*Daylight Lost Since Yesterday: ~2 minute and 59 seconds

*Latest Sunrise Before Daylight Saving Time Ends: November 4th (7:56 AM)
*Next Sunset At/Before 6:00 PM: November 1st (6:00 PM)


Minnesota Weather Outlook

Another warm, beautiful day is expected Thursday with temperatures in the low to mid 70s in central and southern Minnesota and mainly sunny skies. Many areas of northern Minnesota should make it into the 60s, but Grand Marais looks to stay in the 50s.

Across most of the state, highs will be 10-15 degrees above average for this time of year Thursday.


Enjoy the nice weather through the end of the week (including that 80 degree day mentioned above on Friday) as a change will be coming as we head into the weekend. A cold front will pass through Saturday, bringing the chance of some thunder with it along with cooler temperatures. Another front will move through early next week. Both of these fronts will help usher in some of the coolest weather so far this season into the region, with highs only in the 50s by next Tuesday in the Twin Cities.

A cold front moving through Saturday will bring the best chance of accumulating rain since last weekend to the state. Rainfall amounts in the Twin Cities are expected to be around a half an inch, with higher amounts expected across parts of southern Minnesota into Wisconsin. Showers will be possible as early as the morning hours Saturday across southern Minnesota, with a few thunderstorms possible during the afternoon.

A second chance of rain exists in the extended outlook as we head into next week with that second cold front that moves through. I hate to say this... but there is even the chance of a few snowflakes across portions of the state next Tuesday.


National Weather Outlook

Rain and high elevation snow will continue across the Pacific Northwest into the day on Thursday as a cold front moves through the region - even as far south as northern California. We could see some flooding from this rain, as some mountain ranges could pick up a half an foot or more of rain through the end of the week. A low pressure center could bring some showers and storms to parts of the desert Southwest Thursday. A few showers and storms will be possible along the Texas coast by the evening hours. Meanwhile, a stalled front will bring parts of Florida more scattered showers and storms. Most of the rest of the nation will see mainly sunny skies and fairly warm temperatures for this time of year.

Highs across many areas of the nation Thursday will be above average for this time of year, with the greatest departure from averages found in the Northern Plains and New England. With that cold front coming onshore along the west coast, highs will be slightly below average.

Temperatures will be warming across the upper Midwest the next couple days, with highs approach 80 in Bismarck and Rapid Citiy Tuesday, then reaching that same mark Friday in the Twin Cities. However, you can see that cold front moving through the region this weekend, quickly dropping highs behind it by at least 10-20 degrees. Another cold front early next week will bring even cooler air into the region.

We are expecting high pressure to build into the Great Basin this weekend. This will lead to quickly warming temperatures across the Southwest, with record highs possible for areas like Los Angeles, San Diego and Tucson by Monday.

Record highs will continue into Tuesday across the region, including in Los Angeles, Phoenix and Tucson.

The heaviest rain over the next five days (through the weekend) will be across the Northwest, where we'll watch several systems move through. Some heavy rain will also be possible across parts of the southern Plains/lower Mississippi Valley as a system moves through during the weekend, potentially bringing more than 2" of rain to the region.

As a system passes through parts of the southern and central Plains this weekend, some severe weather will be possible Saturday from Kansas to the Dallas area. Damaging winds would be the main threat with any severe storms.


More Lightning In Shipping Lanes?

That’s the conclusion based off a recent study, and it has to do with pollution those ships produce. More from Scientific American: “When lightning sparks across the sky, it sends out low-frequency radio waves that researchers can use to determine its location. Recently, scientists were looking over a map of lightning activity, when they noticed something strange: narrow lines of increased lightning frequency stretching across the Indian Ocean and the South China Sea. Straight features like these are rare on a spherical, spinning planet, except where humans are up to something. In this case, sending ships across the sea.” (Image: Observed annual-mean WWLLN lightning density for 2005–2016 in the eastern Indian Ocean and the South China Sea. (b) PM2.5shipping emissions estimates from EDGAR database for 2010, both at 0.1° resolution. From Joel A. Thornton et al, Lightning enhancement over major oceanic shipping lanes)

New Danger After California Fires

After the recent California wildfires comes a new danger: hazardous debris. California OES News has more: “Statewide wildfires that scarred communities across Northern and Southern California now pose a new threat. As changing weather patterns and tireless work of more than 11,000 firefighters boost containment lines, communities devastated by the fires face potential health risks associated with the improper handling of fire debris.

Electrical Problems In Puerto Rico

FiveThirtyEight took a dive into why the electrical grid has been a problem in Puerto Rico - long before Maria ever struck the island - and why there will be troubles for potentially years to come: “More than two weeks after Hurricane Maria crashed into Puerto Rico on Sept. 20, Allan Rivera had still not had a full night’s sleep. “Every three hours … I get up and do some maintenance on the generator,” he told me. His wife — who has multiple sclerosis — relies on air conditioning to help minimize her symptoms, but Toa Baja, the town where he lives on the island’s north coast, was still without electricity. That meant Rivera had to keep a gasoline-powered generator running 24 hours a day, seven days a week.” (Image: Aerial photographs of Puerto Rico before and after Hurricane Maria. NOAA)

Jones Act Could Affect Offshore Wind Market

The same government act that had to be revoked so more goods could get to Puerto Rico after Maria could pose a problem for future offshore wind power. More from GreenTechMedia: “The U.S. has lagged behind Europe in building offshore wind for decades. That’s often attributed to uncompetitive pricing and lack of political will. But as more developers work to get U.S. offshore wind projects off the ground in the coming years, the century-old Jones Act has raised concerns that even with improving economics and technological innovation, the process could remain onerous and the costs exorbitant.” (Image: Offshore wind farm near Samsø, Denmark. Photo Credit: Flickr/m.prinke)

“Green” Bond For Fiji 

A new bond from Fiji will specifically raise funds to combat climate change in the country. More from Reuters: “Fiji will issue a $50 million "green" bond in coming weeks to help combat the effects of global climate change, the first developing country to do so, its prime minister said on Wednesday.  The Pacific Island nation is seen as particularly vulnerable to climate change, with some of its 300 low-lying islands susceptible to rising seas.


Thanks for checking in and have a great Thursday! Don't forget to follow me on Twitter (@dkayserwx) and like me on Facebook (Meteorologist D.J. Kayser)!

 - D.J. Kayser

Weather Bliss - Minor Reality Check Brewing - Dangers of Living in Risky Places

About As Good As It Gets in Late October!

Hi, I'm Paul, your weather emcee and Master of the Obvious. You do realize we could be tromping around in thigh-high snow today, right? Blizzards, ice storms & subzero wind chills are all possible by the third week of October, so any day like today is a minor meteorological miracle - an atmospheric reprieve - another day the air won't hurt your face!

This is as good as it gets in late October, when large north-south contrasts in temperature can whip up fierce, full-latitude storms packing gale force winds. Low 70s and blue sky will feel like a revelation later today; about 15F warmer than average. A lukewarm breeze lingers into Saturday, when a strong southerly fetch of moisture may fuel a few showers and T-showers. Sunday looks drier and cooler; by early next week there will be no doubt in your mind it's late October.

Bitter air never comes south all at once, it arrives in waves. Long-range models suggest the first widespread freeze of the season by the last weekend of October. GFS guidance shows 40s to near 50F on Halloween with showers.

Soak up this amazing warmth!

Minor Reality Check Ahead. Nothing shriek-worthy (yet), but by next week there will be no doubt in your mind that it's late October. Yep, you could see this coming. Twin Cities ECMWF numbers: WeatherBell.

2 Weeks Out: Zonal, But Trending Colder. It's time, long nights and fresh snow are brewing up chilly air across Alaska and western Canada, and this surge of numb will draw closer as we push into early November. Temperatures may rebound a bit for Minnesota around Halloween (50s?) before trending colder after November 1 or so.

November Coin Flip. Right now NOAA's CFS2 (Climate Forecast System) model predicts a warmer than average November for much of Canada and the northern USA; a cold bias for the Gulf Coast. Place your bets. Map: WeatherBell.

Firefighters Gaining Ground Against California's Deadliest Ever Blazes. HuffPost has an update and a measure of good news: "Firefighters began gaining ground on wildfires that killed at least 40 people in the past week, the deadliest blazes in California’s history, as winds eased and searchers combed charred ruins for more victims with hundreds still missing. Two of the three most destructive Northern California fires were more than half contained early on Monday, and some residents who fled the flames in hard-hit Sonoma County could be allowed to return home later in the day, officials said. More than 5,700 structures were destroyed by more than a dozen wildfires that ignited a week ago and consumed an area larger than New York City. Entire neighborhoods in the city of Santa Rosa were reduced to ashes. “Overall, things are feeling optimistic. We’re very cautious about that,” said Brad Gouvea, California Department of Forestry and Fire Protection incident commander..."

Wildfires Kill At Least 39 in Portugal and Spain. Reuters has details on some truly apocalyptic blazes: "At least 36 people died in wildfires raging through parched farmlands and forests in Portugal and another three in neighboring northwestern Spain on Sunday and Monday. Firefighters were battling 50 blazes in Portugal and a similar number in Spain. Portugal’s government asked for international help and declared a state of emergency in territory north of the Tagus river - about half of its landmass. Flames ripped across Iberian countryside left tinder-dry by an unusually hot summer and early autumn, fanned by strong winds as remnants of ex-Hurricane Ophelia brushed coastal areas. Television footage showed abandoned villages with many houses in embers and charred vehicles left on the roads..."

It's Time to Ditch the Concept of 100-Year Floods. An article at FiveThirtyEight is a worthy read: "...That’s no surprise to experts, who say the concept of the “100-year flood” is one of the most misunderstood terms in disaster preparedness. In the wake of catastrophic flooding on the Texas coast, the media has been working hard to explain the term, turning out dozens of articles explaining that a “100-year flood” is not a flood that you should expect to happen only once every 100 years. Instead, it refers to a flood that has a 1 percent chance of happening in any given year. Over the course of a 30-year mortgage, a house in a 100-year floodplain has a 26 percent chance of being inundated at least once.1 Stories that emphasize this fact are “doing the Lord’s work,” said Wesley Highfield, professor of marine sciences at Texas A&M University at Galveston. But there are still more holy offices to perform..."

File photo: Reuters, TPX Images.

People Love to Live in Places That Are At Risk for Disaster, "And This Is What Happens". A combination of factors in play. Here's an excerpt from The Washington Post: "...It’s just part of the facts of a highly developed society, is that you have a lot of people and a lot of assets in the face of floods and hurricane and fires,” Brown (D) said at the Wednesday briefing. “And this is what happens.” That might have sounded detached and cerebral while in the middle of a crisis, but it’s what everyone in the emergency management business knows to be true. As a people, we are consistently stepping into the path of destruction. “Natural” disasters have a heavily engineered element. Recent months have delivered a steady pounding of misery, as flooding drowned Houston, hurricanes chewed through Florida, the U.S. Virgin Islands and Puerto Rico, and wildfires killed dozens of people in California. If it feels like these things are getting worse, experts say that’s because, in some cases, they are..."

Map credit: USDA, Silvis Lab, NOAA - Washington Post.

California's Fires Aren't "Natural" - Humans Made Them Worse At Every Step. Additional perspective via Vox: "...The study projected that by 2050, 645,000 houses in California will be built in ‘very high’ wildfire severity zones. “We are definitely seeing [construction in fire-prone regions] happen more and more: 95 percent of the population of the state lives on 6 percent of the land,” said Lynne Tolmachoff, a spokesperson for the California Department of Forestry and Fire Protection. Californians are drawn to views of mountains, forests, and grasslands and are building ever closer to these features that often have a propensity to burn. And places like Napa and Sonoma counties, picturesque regions that are now charred, have some of the fastest-growing property values and highest-priced homes in the United States. This proximity is part of what’s driving the death toll..."

Map credit: "A map showing population density growth projections (left) and a map showing fire hazards." Mann et al. | Land Use Policy

Northern California is Facing Catastrophic Wildfires More Typically Seen in the South. Experts Aren't Sure Why. A story at The Los Angeles Times caught my eye; here's a clip: "...Until last week, 13 of the 20 most destructive — and 16 of the 20 deadliest — wildfires in modern state history occurred in Southern California. Two years ago, the Valley fire in Lake, Napa and Sonoma counties made the list when it claimed four lives and destroyed 1,955 structures. “It seems like every summer now we’re seeing some big, horrific event like this. Why?” Moritz said. “How much of this is climate change? Was some of this left over from five years of drought?” he said. “How much of this is because we’ve built increasing numbers of homes and communities in relatively fire-prone landscapes?” The last is unquestionably a factor..."

For Clean Energy Jobs, Sky's the Limit. The Star Tribune reports: "...Osborn’s job, wind technician, is the fastest growing occupation in the nation. As utilities rapidly increase the amount of power they get from wind farms, workers willing and able to climb hundreds of feet to keep turbines running smoothly are in high demand. Students in wind power training programs in Minnesota are getting jobs as soon as they graduate or even before. “I do what pays the bills, and I looked at what was happening and will be happening for the next 30 years, and wind maintenance seemed win-win,” said Osborn, who works for Vestas, a global wind energy giant. As wind and solar energy have grown, they’ve created a tide of jobs nationwide in fields from construction to manufacturing. Renewable energy jobs, most of which are in wind and solar, grew by 16 percent to around 6,200 in Minnesota from 2015 to 2016, according to a recent study by Clean Energy Economy Minnesota, an industry-led nonprofit..."



Conservative Think Tank: Plan to Help Coal, Nuclear Power "Arbitrary". TheHill has the story: "...Perry’s proposal aims to prop up coal and nuclear plants by mandating higher payments for the electricity they generate, arguing the two power sources are able to store so much of their fuel on site that they help support the reliability and resilience of the electric grid. But Philip Rossetti, an AAF data analyst, said the plan “does not promote a policy that would necessarily achieve” a more stable electricity system, and instead would “arbitrarily value nuclear and coal power above their market rates.” “The only effect of the [proposal] is to set an arbitrary target of on-site fuel requirements that values coal or nuclear power, regardless of if those sources are able to provide resiliency and reliability at least cost,” Rossetti’s analysis says. AAF’s disapproval of Perry’s plan comes as others raise questions and doubts about the proposal..."

After Hurricane Power Outages, Looking to Alaska's Microgrids for a Better Way. NPR reports: "...More places are exploring creating microgrids after a spate of hurricanes and other storms knocked out power to millions in recent years. In Puerto Rico, especially, advocates say this could help key institutions like hospitals and military bases keep the lights on when the larger grid goes down. They might want to look north — far north — for guidance. "Alaskans have been doing this for 50 years," says Ian Baring-Gould, of the National Renewable Energy Lab in Boulder, Colorado. He says the state's remote communities have "an amazing wealth of expertise in that area." Of course, not all of Alaska's microgrids run on renewable energy..."

Tech Addiction is More of a Problem Than People Realize. Arianna Huffington explains in a story at "We are at an inflection point in our relationship with technology. Technology allows us to do amazing things that have immeasurably improved our lives. But at the same time, it’s accelerated the pace of our lives beyond our ability to keep up. And it’s getting worse. We’re being controlled by something we should be controlling. And it’s consuming our attention and crippling our ability to focus, think, be present, and truly connect with ourselves and the world around us. The numbers only confirm what we all know to be true — we’re addicted. A 2015 Bank of America report found that over 70 percent of Americans sleep next to or with their phone. This addiction comes at a cost. A Pew study from the same year found that 89 percent of phone owners said they’d used their phones in their last social gathering, and 82 percent felt that when they do this it damages the interaction..." (File image: LinkedIn).

Star Collision Scatters Gold and Platinum. CNN reports it was an astronomical gong show. "For the first time, two neutron stars in a nearby galaxy have been observed engaging in a spiral death dance around one another until they collided. What resulted from that collision is being called an "unprecedented" discovery that is ushering in a new era of astronomy, scientists announced Monday. "We can now fill in a few more tiles in the jigsaw puzzle that is the story of our universe," said Laura Cadonati, deputy spokeswoman for the LIGO Scientific Collaboration and professor in the school of physics at Georgia Tech. The collision created the first observed instance of a single source emitting ripples in space-time, known as gravitational waves, as well as light, which was released in the form of a two-second gamma ray burst. The collision also created heavy elements such as gold, platinum and lead, scattering them across the universe in a kilonova -- similar to a supernova -- after the initial fireball..."

U.S. Vs. Japan: Giant Robots Are About to Face Off, Fighting For Their Country. Looks like all those Saturday morning cartoons about transformers are coming true. reports: "...It will battle one of Suidobashi's Kurata robots that, according to PC Mag, weighs 6.5 tons and is about 13 feet tall. When responding to MegaBots' initial challenge two years ago, Suidobashi CEO and founder, Kogoro Kurata had said his team couldn't let another country win because giant robots were part of Japanese culture. MegaBots co-founder, Brinkley Warren, told CNBC in 2015 that the fight could potentially pave the way for a fighting robot league and a billion-dollar sport. Prospective fighting robot fans can watch the battle on MegaBots' Twitch channel on Tuesday, Oct. 17 at 7 p.m. PT..."

Headwaters of the Mississippi. Odds are you knew this already, but just in case Atlas Obscura provides a reminder: "Everything has to start somewhere, and the Mississippi River starts in Itasca State Park in Minnesota. The official beginning of the mighty river is on one side of a small rock dam where water from Lake Itasca begins to flow, soon to be joined by water from many other tributaries on its journey to the gulf. At the watershed, the river is tranquil and shallow; it’s a great spot for wading. A large post has been installed next to the headwaters since the 1930s, officially proclaiming the park’s status as the source of the great river and listing its distance to the gulf as 2,552 miles..."

Image credit: R. Stemple.

73 F. high temperature yesterday in the Twin Cities.

58 F. average high on October 17.

72 F. high in the Twin Cities on October 17, 2016.

October 18, 1950: Record high temperatures are set across the area as highs reached the mid to upper 80s. Minneapolis and Farmington saw highs of 87 degrees Fahrenheit, while Albert Lea reached 86 degrees.

October 18, 1916: A blizzard impacts Minnesota. A sharp temperature drop begins as well; Hallock drops from the 60s to 2 above by the 20th.

TODAY: Partly sunny, breezy and mild. Winds: W 10-20. High: 71

WEDNESDAY NIGHT: Partly cloudy, a bit cooler. Low: 43

THURSDAY: Sunny. Just try and stay inside. Winds: S 5-10. High: near 70

FRIDAY: Shorts in late October? Lukewarm sunshine. Winds: S 10-20. Wake-up: 55. High: 75

SATURDAY: Sunny start, few PM T-showers possible. Winds: SW 7-12. Wake-up: 60. High: near 70

SUNDAY: Sunnier, drier, cooler day of weekend. Winds: SW 5-10. Wake-up: 48. High: 62

MONDAY: Mostly cloudy, feels like fall again. Winds: NW 10-20. Wake-up: 47. High: 57

TUESDAY: Partly sunny and brisk. Winds: NW 10-15. Wake-up: 42. High: 51

Climate Stories...

Hurricane Ophelia Sheds Light on Another Climate Change Concern. An article at HuffPost explains: "...Before being downgraded to a post-tropical cyclone, Ophelia was a Category 3 hurricane on Saturday and Sunday. It went farther east than any other previously recorded Category 3 hurricane in the Atlantic Basin and broke a record set in 1980. “As sea surface temperatures continue to warm, the region of the Atlantic Ocean that can support the genesis and strengthening of tropical storms and hurricanes is expanding eastward,” said Michael Mann, a distinguished professor of atmospheric science and the director of the Earth System Science Center at Penn State University. Hurricanes are not only reaching much farther to the east, but they’re forming farther east as well, Mann noted. Hurricane Irma, which devastated parts of the Caribbean and the southeastern United States last month, was the strongest hurricane to ever form as far east in the Atlantic as it did, he said..."

More Hurricanes to Hit Western Europe Due to Global Warming. Here's an abstract of a 2013 paper at Geophysical Research Letters: "We use a very high resolution global climate model (~25 km grid size) with prescribed sea surface temperatures to show that greenhouse warming enhances the occurrence of hurricane-force (> 32.6 m s–1) storms over western Europe during early autumn (August–October), the majority of which originate as a tropical cyclone. The rise in Atlantic tropical sea surface temperatures extends eastward the breeding ground of tropical cyclones, yielding more frequent and intense hurricanes following pathways directed toward Europe. En route they transform into extratropical depressions and reintensify after merging with the midlatitude baroclinic unstable flow. Our model simulations clearly show that future tropical cyclones are more prone to hit western Europe, and do so earlier in the season, thereby increasing the frequency and impact of hurricane force winds..."

Stanford Climate Scientist Addresses Misconceptions About Climate Change. People can adapt to the averages; it's the extremes that tend to wreak havoc. Here's an excerpt of a story from Stanford News that made me do a double-take: "..."People tend to ask, 'When will the average conditions cross a threshold that results in climate change?' But that's not really relevant. People and ecosystems can adapt to the average conditions, but where things fall apart is in the extremes. We experience damages from climate mainly at the extremes, and it's the extremes that can result in disasters. "Farmers might have enough rain on average to grow corn in Illinois. But in a drought, as in 2012, yields get whacked. Corn yields decline rapidly when temperatures rise above 29 C (84 F). If temperatures are above that 29 C threshold once every 200 years, it may not be a big problem. But if it is every five years, farmers start seeing impacts on yield and, if the high temperatures occur too frequently, on the viability of corn farming in that area. "We're already seeing evidence of climate-change impacts in the increased frequency of extreme events..."

Photo credit: "Poorly developed cornstalks show the effects of prolonged hot, dry weather. Extreme temperatures year after year have an impact on the viability of corn farming in an area, Stanford scientist Chris Field says." Earl D. Walker / Shutterstock