Bus-Sized satellite to re-enter Earth's atmosphere

UARS, a NASA satellite the size of a small bus, will re-enter Earth's atmosphere later this week and it has been grabbing a lot of attention as debris is predicted to make it to the earth's surface. In fact, there has been scientists who put the odds of debris of hitting someone at one in 3200. While this is still quite small, it is a statistically significant risk. Though the statistic has been misquoted by some reporters by saying that your chance of being it is one in 3200. Well, that's not quite true as the odds are for hitting one of the billions on the planet. So it's not as scary as it seems through some reports.

What you can expect though is a brilliant fireball somewhere over our planet. Best estimates place the re-entry time during the late hours of Sept. 23rd over a still-unknown region of Earth. Observers of the rapidly-decaying satellite say it is tumbling and flashing, sometimes almost as brightly as Venus. Video images are featured at http://spaceweather.com to show how the doomed satellite looks through a backyard telescope.

If you would like to catch a last glimpse of UARS streaking across the night sky should check SpaceWeather's Satellite Tracker for flyby times: http://spaceweather.com/flybys . You can also turn your smartphone into a UARS tracker by downloading our Simple Flybys app: http://simpleflybys.com

A Brisk Change to Autumn

Over the past couple of days, we seemed to have leapfrogged from the month of August right into October.  Temperatures topped out near 80 in many spots on Wednesday, while afternoon temperatures were only hovering in the 50s on Thursday after a potent cold front pushed on through.  I know I was a bit surprised when I left work Thursday afternoon and it felt so crisp despite the sun being out.  While we've had some damp, chilly days recently, that was probably the first cool, dry afternoon we've had since the spring.  After the cool day, we dropped to near 40 Thursday night and many outlying areas were in the 30s - it's a night we would typically see later in October, not in September.  DuBois hit 36 degrees Friday morning, and some of the outlying areas dropped to near the freezing mark, especially near and north of Interstate 80.

We didn't get the brunt of the cold air, though, which was centered over Minnesota.  The "Icebox of the Nation," located in International Falls, Minnesota, dipped down to 19 degrees Thursday morning.  That set a record as the coldest temperature ever recorded in the month of September.  It was the first time since 1924 that Chicago recorded back-to-back high temperatures below 60 degrees.  And the front brought some much needed relief from the heat in Dallas, where the mercury hit 107 degrees on Tuesday, but didn't even hit 80 on Thursday.

The unseasonably cold air was thanks to a very strong area of high pressure (especially for this time of year) that came down from Canada.  Those of you that have home barometers may have noticed some high readings the past couple of days, up between 30.30" to 30.40" of mercury.  These strong highs give us our coldest nights in the winter, and this time brought us an early start to autumn.

Those of you that aren't ready for the cooler weather - don't worry.  70s will return to the forecast as the sun is still relatively strong this time of year and it's impossible to keep it this cool for the rest of the month.

--Meteorologist Brian Thompson

NOAA: Globe had eighth warmest August on record

The globe had its eighth warmest August since record keeping began in 1880, while June through August was the seventh warmest such period on record. The Arctic sea ice extent was the second smallest for August on record at 28 percent below average.

This monthly analysis from NOAA’s National Climatic Data Center is part of the suite of climate services NOAA provides government, business and community leaders so they can make informed decisions.

Global Temperature Highlights: August

• The combined global land and ocean average surface temperature for August 2011 was the eighth warmest on record at 61.09 F (16.15 C), which is 0.99 F (0.55 C) above the 20^th century average of 60.1 F (15.6 C). The margin of error associated with this temperature is +/- 0.16 F (0.09 C).
• Separately, the global land surface temperature was 1.51 F (0.84 C) above the 20^th century average of 56.9 F (13.8 C), making this the second warmest August on record. The margin of error is +/- 0.32 F (0.18 C). Warmer-than-average conditions occurred across most of North America and the northern half of South America, southern Greenland, eastern Russia, Mongolia, most of Europe, northern Africa to Southwest Asia, and southern Australia. Cooler-than-average regions included western Russia, Alaska, Chile, Argentina, and Uruguay.
• The August global ocean surface temperature was 0.79 F (0.44 C) above the 20^th century average of 61.4 F (16.4 C), making it the 12^th warmest August on record. The margin of error is +/- 0.07 F (0.04 C). The warmth was most pronounced across the north central, northwest, and south central Pacific Ocean, the north-central Atlantic, and the Labrador Sea.
• Scotland and Northern Ireland had their coolest average monthly August temperatures since 1993. Scotland was 1.4 F (0.7 C) below its 1971–2000 average of 55.2 F (12.9 C), while Northern Ireland was 1.3 F (0.8 C) below its average temperature of 57.6 F (14.2 C).
• Australia’s August 2011 average maximum temperature was the fifth warmest August in its 62-year period of record. The state of Tasmania had its all-time warmest August maximum and minimum temperatures on record.

Global Temperature Highlights: June – August

• The combined global land and ocean average surface temperature for June – August 2011 was the seventh warmest on record at 61.11 F (16.16 C), which is 1.01 F (0.56 C) above the 20^th century average of 60.1 F (15.6 C). The margin of error associated with this temperature is +/- 0.16 F (0.09 C).
• Separately, the global land surface temperature was 1.55 F (0.86 C) above the 20^th century average of 56.9 F (13.8 C), which was the third warmest June – August period on record. The margin of error is +/- 0.29 F (0.16 C). Warmer-than-average conditions occurred across Mexico, the eastern two-thirds of the United States and Canada, and most of Europe and Asia. Cooler-than-average regions included southern Alaska, Chile, Argentina, Uruguay, and northern Australia.
• The June – August global ocean surface temperature was 0.81 F (0.45 C) above the 20^th century average of 61.5 F (16.4 C), making it the 11^th warmest June – August on record. The margin of error is +/- 0.07 F (0.04 C). The warmth was most pronounced across the north central, northwest, and south central Pacific, the equatorial north Atlantic, and the Labrador Sea.

Global Temperature Highlights: Year to Date

• The combined global land and ocean average surface temperature for the January – August period was 0.92 F (0.51 C) above the 20^th century average of 56.9 F (13.8 C), making it the 11^th warmest such period on record. The margin of error is +/- 0.18 F (0.10 C).
• The January – August worldwide land surface temperature was 1.40 F (0.78 C) above the 20^th century average — the seventh warmest such period on record. The margin of error is +/- 0.36 F (0.20 C). The global ocean surface temperature for the year to date was 0.74 F (0.41 C) above the 20^th century average and was the 11^th warmest January-August period on record. The margin of error is +/-0.07 F (0.04 C).
• Last month, La Niña conditions returned. According to NOAA’s Climate Prediction Center, La Niña is expected to gradually strengthen and continue into the Northern Hemisphere winter 2011/12.

Polar Sea Ice and Precipitation Highlights

• The average Arctic sea ice extent during August was 28 percent below average, ranking as the second smallest August extent since satellite records began in 1979. The extent was 830,000 square miles (2.15 million square kilometers) below average and 61,800 square miles (160,000 square kilometers) above the record low August extent set in 2007.
• According to model analysis by the University of Washington’s Polar Science Center, Arctic sea ice volume, which depends on both ice thickness and extent, reached a record low of 1,026 cubic miles (4,275 cubic kilometers) on August 31, 2011, breaking the previous lowest volume set on September 15, 2010. The average August 2011 volume was 1,200 cubic miles (5,000 cubic kilometers). This value is 62 percent lower than the 1979–2010 average and 72 percent lower than the maximum in 1979.
• Conversely, the August 2011 Antarctic sea ice extent was 0.08 percent above the 1979–2000 average and was the 14^th smallest (20^th largest) August extent since records began in 1979.
• The June – August 2011 (Southern Hemisphere winter) was Australia’s first drier-than-normal season since September – November 2009 and was 12 percent below the 1971–2000 average.

Scientists, researchers and leaders in government and industry use NOAA’s monthly reports to help track trends and other changes in the world's climate. This climate service has a wide range of practical uses, from helping farmers know what and when to plant, to guiding resource managers with critical decisions about water, energy and other vital assets.

A La Nina Developing Again

La Niña, which contributed to extreme weather around the globe during the first half of 2011, has re-emerged in the tropical Pacific Ocean and is forecast to gradually strengthen and continue into winter. Today, forecasters with NOAA’s Climate Prediction Center upgraded last month’s La Niña Watch to a La Niña Advisory.

NOAA will issue its official winter outlook in mid-October, but La Niña winters often see drier than normal conditions across the southern tier of the United States and wetter than normal conditions in the Pacific Northwest and Ohio Valley.

“This means drought is likely to continue in the drought-stricken states of Texas, Oklahoma and New Mexico,” said Mike Halpert, deputy director of the Climate Prediction Center. “La Niña also often brings colder winters to the Pacific Northwest and the northern Plains, and warmer temperatures to the southern states.”

Climate forecasts from NOAA’s National Weather Service give American communities advance notice of what to expect in the coming months so they can prepare for potential impacts. This service is helping the country to become a Weather Ready Nation at a time when extreme weather is on the rise.

Seasonal hurricane forecasters factored the potential return of La Niña into NOAA’s updated 2011 Atlantic hurricane season outlook, issued in August, which called for an active hurricane season. With the development of tropical storm Nate this week, the number of tropical cyclones entered the predicted range of 14-19 named storms.

The strong 2010-11 La Niña contributed to record winter snowfall, spring flooding and drought across the United States, as well as other extreme weather events throughout the world, such as heavy rain in Australia and an extremely dry equatorial eastern Africa.

La Niña is a naturally occurring climate phenomenon located over the tropical Pacific Ocean and results from interactions between the ocean surface and the atmosphere. During La Niña, cooler-than-average Pacific Ocean temperatures influence global weather patterns. La Niña typically occurs every three-to-five years, and back-to-back episodes occur about 50 percent of the time. Current conditions reflect a re-development of the June 2010-May 2011 La Niña episode.

NOAA: U.S. experiences second warmest summer on record

NOAA: U.S. experiences second warmest summer on record

Texas has warmest summer on record of any state

The blistering heat experienced by the nation during August, as well as the June through August months, marks the second warmest summer on record according to scientists at NOAA’s National Climatic Data Center (NCDC) in Asheville, N.C. The persistent heat, combined with below-average precipitation across the southern U.S. during August and the three summer months, continued a record-breaking drought across the region.

The average U.S. temperature in August was 75.7 degrees F, which is 3.0 degrees above the long-term (1901-2000) average, while the summertime temperature was 74.5 degrees F, which is 2.4 degrees above average. The warmest August on record for the contiguous United States was 75.8 degrees F in 1983, while its warmest summer on record at 74.6 degrees F occurred in 1936. Precipitation across the nation during August averaged 2.31 inches, 0.29 inches below the long-term average. The nationwide summer precipitation was 1.0 inch below average.

This monthly analysis, based on records dating back to 1895, is part of the suite of climate services NOAA provides.

U.S. Climate Highlights – August

· Excessive heat in six states – Arizona, Colorado, New Mexico, Texas, Oklahoma, and Louisiana – resulted in their warmest August on record. This year ranked in the top ten warmest August for five other states: Florida (3^rd), Georgia (4^th), Utah (5^th), Wyoming (8^th), and South Carolina (9^th).The Southwest and South also had their warmest August on record.

· Only nine of the lower 48 states experienced August temperatures near average, and no state had August average temperatures below average.

· Wetter-than-normal conditions were widespread across the Northeastern United States, which had its second wettest August, as well as parts of the Northern Plains and California. Drier-than-normal conditions reigned across the interior West, the Midwest, and the South.

· Hurricane Irene made landfall near Cape Lookout, N.C., as a Category 1 storm on August 27, marking the first hurricane landfall in the U.S. since Hurricane Ike in September 2008. Irene made a second landfall in New Jersey as a hurricane on August 28, marking only the second recorded hurricane landfall in that state.

· Irene contributed to New Jersey, New York, Vermont, and New Hampshire having their wettest August on record. Meanwhile, Massachusetts (2^nd), Connecticut (2^nd), Delaware (3^rd), Maine (3^rd), Maryland (5^th), Pennsylvania (5^th), and Rhode Island (9^th) had a top 10 wet August.

· Several major U.S. cities broke all-time monthly rainfall amounts during August. New York City (Central Park) measured 18.95 inches of rain, exceeding the previous record of 16.85 inches in 1882. In Philadelphia, 19.31 inches of rain was observed, besting the previous monthly record of 13.07 inches in September 1999.

· Louisiana (3rd), Tennessee (4th), Texas (5th), Mississippi (6th), Georgia, (6th), Illinois (8th), Washington (9th), and Alabama (9th) had precipitation totals among their top ten driest on record.

· Despite record rainfall in parts of the country, drought covered about one-third of the contiguous United States, according to the U.S. Drought Monitor. The Palmer Hydrologic Drought Index indicated that parts of Louisiana, New Mexico, Oklahoma and Texas are experiencing drought of greater intensity, but not yet duration, than those of the 1930s and 1950s. Drought intensity refers to the rate at which surface and ground water is lost, due to a combination of several factors, including evaporation and lack of precipitation.

· An analysis of Texas statewide tree-ring records dating back to 1550 indicates that the summer 2011 drought in Texas is matched by only one summer (1789), indicating that the summer 2011 drought appears to be unusual even in the context of the multi-century tree-ring record.

U.S. Climate Highlights – Summer

· Texas, Oklahoma, New Mexico, and Louisiana had their warmest (June-August) summers on record. Average summer temperatures in Texas and Oklahoma, at 86.8 degrees F and 86.5 degrees F, respectively, exceeded the previous seasonal statewide average temperature record for any state during any season. The previous warmest summer statewide average temperature was in Oklahoma, during 1934 at 85.2 degrees F.

· Fifteen states had a summer average temperature ranking among their top ten warmest. West of the Rockies, a persistent trough brought below-average temperatures to the Pacific Northwest, where Washington and Oregon were the only states across the lower 48 to have below-average summer temperatures.

· Texas had its driest summer on record, with a statewide average of 2.44 inches of rain. This is 5.29 inches below the long-term average, and 1.04 inches less than the previous driest summer in 1956. New Mexico had its second driest summer and Oklahoma its third driest summer. New Jersey and California had their wettest summers on record with 22.50 inches and 1.93 inches, respectively.

· The U.S. Climate Extremes Index, a measure of the percent area of the country experiencing extreme climate conditions, was nearly four times the average value was during summer 2011. This is the third largest summer value of the record, which dates to 1910. The major drivers were extremes in warm minimum and maximum temperatures and in the wet and dry tails of the Palmer Drought Severity Index.

· Based on NOAA's Residential Energy Demand Temperature Index, the contiguous U.S. temperature-related energy demand was 22.3 percent above average during summer. This is the largest such value during the index’s period of record, which dates to 1895.

Other U.S. Climate Highlights

· During the six-month period (March-August), much-above-average temperatures dominated the southern and eastern United States. New Mexico, Oklahoma, Texas, Louisiana, South Carolina, and Florida, all experienced their warmest March-August on record. Cooler-than-average temperatures dominated the West and Northwest.

· For the year-to-date period, the average statewide temperature for Texas was 69.9 degrees F, the warmest such period on record for the state. This bests the previous record for the year-to-date period of 69.8 degrees F in 2000.

· For precipitation year-to-date, New Mexico, Texas, and Louisiana have all had their driest January-August periods on record, while Ohio, Pennsylvania, New York, New Jersey, and Connecticut were record wet during the same period.

NCDC’s monthly reports are based on preliminary data, which are subject to revision. Additional quality control is applied to the data when late reports are received several weeks after the end of the month and as new scientific methods improve NCDC’s processing algorithms.