The summer of 2012 is in the running for one of the
top three hottest summers in the past 60 years in the United States and
southern Canada.
Steven A. Root,
Certified Consulting Meteorologist and President and CEO of WeatherBank, Inc.
has been examining hourly and daily temperatures in 59 hub cities dating back
to Jan. 1, 1950.
WeatherBank is an
AccuWeather, Inc. long-range forecasting and data partner.
Root computes the
cooling degree days (CDD) for each city, each day of the year. Cooling degree
days are the number of degrees that a day's average temperature is above 65
degrees. The period from May 15 to Sept. 15 is considered to be the air conditioning/cooling
season for the U.S. and Canada.
Root is estimating
this summer to finish up with 59,484 CDDs based on what has happened thus far
and what is projected.
"The summer of
2012 is on pace to finish third hottest on the list of 62 summers since 1950,
but is still in the running for number two or one on the list," Root said.
The hottest summer
on Root's records was last year (2011) with 60,402 CDDs. The second hottest
summer, according to Root was 1951 with 60,078 CDDs. Comparatively, the coolest
summer was 1965 with 43,337 CDDs.
Root's approximate
60-year average is 51,923 CDDs. The commonly used National Oceanic and
Atmospheric Administration's (NOAA) most recent 30-year average is 53,933 CDDs.
In the past 10 years, the average CDDs is 56,134.
"This tells you
that the summers are trending hotter in the most recent decades and years for
the U.S. and southern Canada as a whole," Root said.
In the U.S. as a whole, seven out of the last 10
summers have been hotter than the 62-year average. This compared to the 1960s
and 1970s, when seven out of 10 summers were cooler than the NOAA's recent
30-year average.
During the 1980s and
1990s, again in the U.S. as a whole, the number of summers were about a 50/50
split being warmer or cooler than the NOAA 30-year average.
It is important to
note that during an average summer across the U.S. and southern Canada, one
part can be and often is significantly warmer or cooler than the local average.
Last summer, heat
got a later start, compared to this summer. Root expects the period through
Sept. 15 to fall a bit behind last year's pace and it is for that reason that
this summer will probably fall a bit short of last year in terms of total CDDs.
"It will still
be close and another big, broad surge of extreme heat can push the summer over
the top in terms of CDDs," Root said.
According to AccuWeather.com's long-range
forecasting department, headed by veteran meteorologist Paul Pastelok, "We
expect more surges of heat to build out of the Plains and into the East in the coming
weeks."
"While cooler
and potentially wetter conditions are projected to expand in the West, the most
extreme warmth, relative to normal, could be forced out of the Plains and take
root in the Great Lakes and Northeast, during September and October,"
Pastelok added.
Root and Pastelok
agreed that dry soil conditions and existing extreme warmth could continue to
skew averages through the remainder of the summer over much of the country,
into the fall and so on.
Only when sufficient
soil moisture returns will things begin to behave as they should.
Soil moisture takes
energy away from the sun, so that less of the sun's energy is available to heat
the ground and the air nearest the ground.
How Does Root Estimate the Reminder of the Summer?
First, all available
computer models in the public and private sector are examined.
Next, all past years
are examined and the top candidates for similar-looking weather and temperature
patterns to this summer are pulled and weighted in. These are known as analog
years.
Finally, the analog
years are adjusted by shifting the start of the season forward and backward to
account for potential late-starting or early-starting summer patterns.
In the 15 years Root
has been making seasonal weather projections, he has run into some problems in
the most recent years, due to more extremes in temperature (hot and cold) than
during the prior years.
"In the recent
five years, I have had to manually override the data due to the high number and
magnitude of temperature extremes, compared to prior decades," Root said.
Root chose 1950 as
the starting point since this is when a high number of the reporting stations
throughout the U.S. and southern Canada began recording hourly temperature
data.
"Even with this
starting point we had to create a few virtual weather stations for the first
few years, based on knowledge of weather in the missing locations, relative to
surrounding actual stations," Root said.
AccuWeather
Enterprise Solutions (AES) provides ag-focused forecasts from expert
agricultural meteorologists that help manage risk, highlight opportunity and
increase profitability.
AES works directly with your company to provide
the long-range predictions that impact yields including seasonal, planting,
harvesting and drought forecasts. It also provides timely warnings for severe
weather, including hail, frost, thunderstorms, extreme heat and cold and more
for growing regions around the world.
For
more information, contact us at 814-235-8600 or email sales@AccuWeather.com.
Source : AccuWeather