Four Major U.S. Heat Records Fall In Stunning NOAA Report

For Litany Of U.S. Cities, 2012 Temperatures Are Unprecedented

JR: Here are two Climate Central pieces on the amazing heat waves that hit the country.

Year-to-Date divisional temperature rankings from NOAA. Click on image for a larger version.

by Andrew Freedman, via Climate Central

Four major heat records fell in a stunning new climate report from NOAA on Thursday. The lower 48 states set temperature records for the warmest spring, largest seasonal departure from average, warmest year-to-date, and warmest 12-month period, all new marks since records began in 1895. While the globe has been tracking slightly cooler than recent years — thanks in part to the influence of now dissipated La Nina conditions in the tropical Pacific — the U.S. has been sizzling.

The average springtime temperature in the lower 48 was so far above the 1901-2000 average — 5.2°F, to be exact — that the country set a record for the largest temperature departure for any season on record since 1895.

Spring 2012 beat 1910, which had held the title for record warm spring, by a healthy margin of 2°F. No doubt much of this was driven by the massive heat wave that gripped the country during March, but unusual warmth continued during April and May, albeit not as intense. Such warming trends are consistent with both the influence of manmade global warming, particularly the prevalence of record warm nighttime temperatures, and natural variability has also favored warmer-than-average conditions so far this year. Studies show that as greenhouse gases continue to increase in the atmosphere, the odds of heat extremes are growing as well.

Climate Extremes Index showing 2012 has had the most extreme weather to date for any year on record. Credit: NCDC.

According to NOAA’s National Climatic Data Center, the spring of 2012 “was the culmination of the warmest March, third warmest April, and second warmest May. This marks the first time that all three months during the spring season ranked among the 10 warmest, since records began in 1895.”

Des Moines, Iowa offers a case study of just how warm it’s been. The year-to-date there has averaged a whopping 8 degrees F above average, with many other cities across the country tracking close to that figure as well.

Temperature trend chart for Des Moines, IA, showing that 2012 is the warmest year to date by far. Click for a larger image. Credit: NOAA/NCDC.

Temperature trend chart for Des Moines, IA, showing that 2012 is the warmest year to date by far. Click for a larger image. Credit: NOAA/NCDC.

Most of the states that experienced record or near-record warmth this spring were located east of the Rocky Mountains, with 31 states setting records for warmest spring temperatures. Remarkably, not a single state in the lower 48 was cooler than average this spring, and only Oregon and Washington had spring temperatures that were close to average. Although there were exceptions, much of the country had a drier-than-average spring with Colorado, Delaware, Indiana, Utah, and Wyoming coming in with a top 10 driest spring.

The record warmth helped propel the U.S. Climate Extremes Index, which tracks the highest and lowest 10 percent of extremes in temperature, precipitation, drought and tropical storms and hurricanes across the contiguous U.S., to a record-large 44 percent during the March-May period, which was more than twice the average value. “Extremes in warm daytime temperatures (81 percent) and warm nighttime temperatures (72 percent) covered large areas of the nation” were mainly responsible for this record.

Chart showing the warmest 12-month periods on record in the lower 48 states. Click on image for a larger version. Credit: NOAA/NCDC.

Spring was unusual for the pre-season tropical weather, as two tropical storms developed before the official start of the Atlantic Hurricane Season on June 1. Tropical Storm Beryl made landfall near Jacksonville, Fla., on May 28, and brought heavy rainfall to parts of the Southeast that were in the grips of a severe drought. This year marked the third time on record that two tropical storms occurred during May in the North Atlantic Basin.

Major drought has remained elsewhere, though, and drought plus high winds led to ideal conditions for wildfires in the West. The White-Water Baldy Fire Complex in New Mexico, which was the result of two separate fires that combined into a massive conflagration, broke the record set just last year for the largest wildfire in New Mexico history.

Andrew Freedman is the Senior Science Writer for Climate Central. This piece was originally published at Climate Central and is reprinted with permission.

JR: And here is a second, related, CC piece.

For Litany of U.S. Cities, 2012 Temps Are Unprecedented

by Andrew Freedman, via Climate Central

So far this year, the U.S. is running a distinct fever, as the lower 48 states had its warmest January-to-May period on record, according to the National Oceanic and Atmospheric Administration (NOAA). Other longstanding records have fallen as well, including the record for warmest spring, which dated back to 1910 and was smashed by 2°F, warmest 12-month period, and largest seasonal departure from average.

Taking a deeper dive into the temperature statistics reveals fascinating insights into just how warm it’s been at the local level in many locations. As NOAA stated on its website on Thursday, “In some locations, 2012 temperatures have been so dramatically different that they establish a new “neighborhood” apart from the historical year-to-date temperatures.”

The year-to-date numbers were certainly boosted by the unprecedented heat wave that took place during March, when several thousand warm temperature records were shattered from the Rocky Mountain states on eastward. Global warming raises the odds of heat extremes, and natural variability has favored warmer-than-average conditions so far this year as well. This has had a profound effect at the local level this year.

Take Chicago, for example. With a January-to-May average temperature that was 7.1°F above average, or 3.1 standard deviations above the 1981-2000 norm, this year so far stands in a class of its own — the warmest in the past 54 years of recordkeeping. NOAA’s chart (click on it to open a larger version) clearly illustrates this, with the bright red line depicting 2012 temperatures.

Haywood plot showing how temperatures in 2012 so far stack up against previous years for Chicago. Click on image for a Credit: NOAA/NCDC.

Here’s NOAA’s technical explanation for how such charts, called “Haywood Plots”, are calculated:

The unusualness is based upon the number of standard deviations difference between the 2012 value and the station’s average, based on the station’s history.

…As you read from left to right, a particular year’s trace represents the average of all previous days during that year. For this reason, these plots are often very noisy early in a period (towards the left), but they provide an outstanding representation of unusualness over the whole of the period.

Here’s what the chart looks like for St. Paul, Minn., where the January-to-May period came in at 7.5°F above average, for the warmest in 74 years of recordkeeping there.

Haywood plot showing how temperatures in 2012 so far stack up against previous years for St. Paul, MN. Click on image for a Credit: NOAA/NCDC.

It was a similar story in Milwaukee, where January-to-May temperatures were 6.2°F above average, or 2.8 standard deviations above the norm. This made it the warmest such period in 71 years of recordkeeping.

Haywood plot showing how temperatures in 2012 so far stack up against previous years for Milwaukee. Click on image for a Credit: NOAA/NCDC.

In Detroit, January-to-May temperatures averaged 5.8°F above average, or 2.9 standard deviations above the norm, for the warmest such period in 54 years.

Haywood plot showing how temperatures in 2012 so far stack up against previous years for Detroit. Click on image for a Credit: NOAA/NCDC.

Lastly, in New York City’s Central Park, where weather records extend further back than at some Midwestern stations, the January-to-May period was 4.7°F above average, making it the warmest such period in 137 years.

Haywood plot showing how temperatures in 2012 so far stack up against previous years for New York. Click on image for a Credit: NOAA/NCDC.

Additional data is available from NOAA’s website, showing how temperatures compared at other cities across the country. There were precious few places that had cooler-than-average temperatures so far this year, the vast majority of them located in the West and Northwest. One exception is Portland, Maine, which somehow beat the heat — with an average temperature of 0.7°F below average. Portland residents can probably thank the cold waters of the Atlantic Ocean for that.

— Andrew Freedman. This piece is reprinted with permission.

Related Climate Progress Posts:

17 Responses to Four Major U.S. Heat Records Fall In Stunning NOAA Report

  1. Michael Stefan says:

    Global temperatures may soon catch up with the U.S., per the latest MEI update:

    With the overall MEI indicating now indicating weak El Niño conditions, one can find a surprisingly high number of key anomalies in the MEI component fields that exceed or equal one standard deviation, or one sigma (compare to loadings figure). During April-May 2012, all of them flag El Niño features – a big change from even just last month…

    …The updated (April-May) MEI registers at +0.71, another large one-month increase of +0.65 sigma that is the 6th highest such increase for this time of year since 1950, which also constitutes the 4th monthly rise of this caliber in a row (second only to the record of SIX such large monthly consecutive increases in 1997, which culminated in the last ‘Super-El Niño’ of 1997-98).

  2. Michelle M says:

    Wow, the left coast has the least effect! There is a god!

  3. Peter M says:

    the warmth continues to build mostly east of the Rockies- in the interior Heartland of the US- in the corn and wheat belts. Not a good omen for the future- climate models have predicted this outcome for awhile.

    One can only imagine the heat in 10 years- as Greenhouse gases in the pipeline begin to show. Meanwhile we continue to add 2-3ppm a year or more to C02 total. Anyone for 420ppm or more by 2020?

  4. From Peru says:

    And do not forget the greenhouse forcing masked by sun-reflecting, cooling aerosols.

    If we drastically cut aerosol emissions, that alone is enough to double the current planetary energy net forcing even without further greenhouse emissions.

    Thus on top of “warming in the pipeline” there is “forcing in the pipeline”

  5. Mulga Mumblebrain says:

    Thank God I’m an atheist!

  6. NOAA has a nice video talking about the warmth that the U.S. has experienced so far this year:

  7. Alex says:

    Republicans need to get to work making it illegal to take into account studies like this. I hear North Carolina is already working on it.

  8. Mark E says:

    Suppose Romney wins, and next year El Nino~ really ramps up; Add a return of record breaking drought to Texas-Oklahoma, but expand it to the Iowa cornfields and the Montana wheatlands…..

    We’d suffer, sure.

    But when it happens, as projections say it will, I would sure like to have a republican in the whitehouse. And I’d like to get a SHORT taste of this many years before it becomes a regular event. Am I nuts to hope for US agricultural collapse in 2013 (but not again until 2025 or later)?

  9. mjcc1987 says:

    We won’t have to worry about things like this when Mitt becomes President. Like Bush, science will be subservient first to politics and then to religion. Don’t that that’s true? Check NC and TX for the future (or lack thereof)

  10. Dennis Tomlinson says:

    “…religious faith is better interpreted as an unseen trap unavoidable during the biological history of our species. And if this is correct, surely there exists ways to find spiritual fulfillment without surrender and enslavement. Humankind deserves better.” ~E.O. Wilson

    And then there’s the age old, “There are no atheists in Fox holes.” -Anon. (‘F’ intended)

  11. squidboy6 says:

    These kind of events have synergistic effects and even greater amounts of carbon dioxide entering the atmosphere will occur.

    The warming of the Great Lakes, the so-called Permafrost, and from the oceans will accelerate. This will make methane more active from these sources, more likely to enter the atmosphere since warming makes dissolved gases less soluble in water and less stable in the frozen soils and bogs.

    Since this is Climate Change there will be cooling events as well and this is where people need to be convinced that it’s regional and temporary – that warming is the actual trend. What a world billions and billions and billions of people have we created?

  12. NOAA has an interesting video that shows that most of the April record high temps that were set across the U.S. occurred in the last decade (2001-2010) and 2011 and 2012.

  13. DallasNE says:

    It has probably been over a year since we have had a single month with below average temps. Both January and March set records for warmest on record — and by no small margin either. There was a town in Michigan that had a day in March where the high temperature broke the old record by 31 degrees. In fact, the low for that day was warmer than the old record high. Our last temp of 32 or colder happened in the first week of March. Normal for that is around April 17th. The last 4 days have been right at 90 and that is about 7 degrees above average.

  14. Thanks for presenting this. These graphs are dramatic and shocking.

    And why did main stream mass media see fit to ignore such a clear data visualization?

  15. h4x354x0r says:

    If you look at the carbon concentrations in the earth’s atmosphere:

    …you will see the increase in carbon concentrations is incredibly consistent: Nearly linear, but not quite. Concentrations accelerate by roughly 1% per year.

    This, despite much larger fluctuations in actual carbon emissions. Climate science deniers latch on to this, and claim it proves there’s no correlation between carbon emissions and atmospheric carbon concentrations.

    Nothing could be further from the truth.

    Earth’s atmosphere weighs about 5.3 Quadrillion Metric Tons.
    We (world) are releasing roughly 32 Million Metric tons per year (and increasing far more quickly than airborne carbon concentrations).
    Do the math. We are dumping about 2-1/2 times more carbon into the atmosphere than stays there. The rest just gets absorbed.

    This does not mean CO2 releases don’t affect airborne CO2 concentrations. It only means the earth can only change atmospheric carbon levels so fast (accelerating at 1% per year). We’re simply exceeding the earth’s ability to increase atmospheric CO2 concentrations, so the earth eats the rest.

    Problem is, what it has recently eaten, isn’t gone. All that carbon is lurking just around the corner; ready and eagerly waiting to come out as soon as the atmosphere can take it. Every shred of science and current and historical evidence of the earth’s climate points to a positive carbon feedback cycle: greenhouse gasses drive heating, which drives the release of more greenhouse gasses, which drives more heating.

    All that extra carbon that has been recently sequestered, but is lurking just around the corner, is the “momentum” behind climate change, and boy have we build up a LOT of momentum over the last 30 years. Even if we drop carbon emissions below what the earth’s atmosphere can increase each year, all the extra carbon we released before that just steps in to take it’s place.

    Few people seem to understand how much momentum there is behind this. It’s basically a runaway freight train, and it’s going to take a lifetime to slow it down. Unfortunately, most planning fails to look past the next quarterly profit statements, let alone look 30 years down the road.

  16. You’ve got it right, h4. It’s no comfort to think about what small natural temperature forcing through spiralling feedbacks led to the breakup of the last ice age. Species extinctions ensued for thousands of years and the seas rose fitfully, over 400 feet! It is useless either to lay blame or to avoid the reality: As civilized people of an industrial age we have without witting jump-started the same inexorable positive feedbacks all over again. How many species will end this time because of us? How high will the seas rise? How many years can we keep emissions up before global heating completely dismisses humanity? The only people who can know the answers conclusively are slated to suffer the results indefinitely, for better or for worse.

    While bowing to realism, I hold high the hope that coal, rock oil and gas have nearly, but not quite yet been committed to the point of despair. Please, if you are a POLICY MAKER or VOTER in a democratic system of government, reread the article above and its responses. Pledge to yourself and to your progeny immediate and drastic policy action in hopes we might leave as our legacy better than a cursed millennium or more spiralling climate change.

    Per Dr. James E. Hansen at
    (slides at


    If we do start working (really hard together) in 2012: A century of 6% per year decreases in fossil carbon emissions along with massive reforestation MAY do the trick to restore a survivable (350 ppm CO2E or lower) climate. If we wait until a decade from now: A century of 15% annual reductions and greater reforestation will be needed. No matter how we might have felt toward one another before, you and I would very likely find civil behavior hard to maintain under that kind of stress. We simply cannot wait any longer to start traveling this hard road together, for as we’ve waited the road heaved into ever larger boulders and crevices, DOUBLING in difficulty just since 2005.

    I particularly like the mechanism of a carbon fee collected at the mine or wellhead and rebated IN FULL back to the individual consumers (and thus the investors) who alone in contemporary society have the power to fix this or fail this. If such an electronic fee/rebate system can be phased in at least for the US and China, I’m optimistic that we may yet have a fighting chance to back away from the catastrophic ledge. If not, then there’s really nothing left to do but diversify our investments in established/promising religions, mind-altering drugs and purer forms of hedonism.

    Let us act NOW to avoid the dreary depths of totality when others dictate actions and limits…for that is the last alternative that will remain open to humankind if we continue to allow these better opportunities to slip away. Inventions already exist that will make us shine as heros in the eyes of all future life; we’ve simply got to transform access to them. A public carbon fee/rebate operating with the good will of people that I see everywhere enables exactly that transition. This should clearly be one issue on which we all can agree. DON’T VOTE FOR ANYTHING LESS!