Mount Etna is the largest volcano in Europe and one of the most active volcanoes in the world. On Thursday morning, December 3rd, southern Italy woke up to see an eruption after two years of silence. Scientists say it was the most violent eruption from the volcano in the past two decades. The intense eruption exploded from Etna’s Voragine crater with ash reaching as high as 10,000 feet into the atmosphere and a fountain of lava as high as 5000 feet. High level winds pushed ash over villages in Sicily and other portions of southern Italy. Volcanic lightning was also seen above Mt Etna on Thursday during the eruption period which lasted less than an hour. The Voragine crater was formed inside of the central crater in 1945 and is among three other craters in the volcano: Bocca Nuova, the crater of the Northeast, and the crater of the Southeast which is said to be the most active one.Read More
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More good news this year for the nation on the extreme weather front as it has been another down year in terms of hurricanes and tornadoes. The Atlantic Basin hurricane season officially ends tomorrow, December 1st, and it is quite likely safe to say that this will be another below-normal year in the US for land falling tropical storm activity. In fact, the US has not been struck by a major hurricane (category 3, 4 or 5) in slightly more than ten years and this is the longest drought of that kind since record-keeping began in 1851. In addition, 2015 is turning out to be another below-normal year for tornadoes across the nation and this too continues a trend that is a decade in the making.Read More
12:40 PM | *Soaking rain event on Thursday to be followed by cold blast for the weekend…coldest weather so far for Sunday and Monday...looking ahead to Turkey Day*
[Today's satellite image of major storm that is headed into the eastern US; courtesy NASA, Capital Weather Gang]
Thursday rain event
A powerful storm system that currently extends from Mexico to Canada is headed towards the eastern US and it will produce a significant rain event for much of the region on Thursday (satellite image above). This is the same storm system that produced heavy snow and winter cold in Colorado and Kansas earlier in the week as well as tornadoes in its warm sector across parts of the central US. The rain is likely to arrive here late tonight and continue through the morning and it could very well have a negative impact on the morning commute in DC, Philly and perhaps even New York City (could hold off there until just afterward rush hour). The winds will be quite gusty tomorrow ahead of a strong cold front and there can be an isolated thunderstorm or two during this upcoming event.
[12Z GFS surface forecast map for Sunday morning (blues=snow); courtesy NOAA, tropicaltidbits.com]
Progressively colder Friday, Saturday and Sunday
This significant rain event will be followed by a colder air mass in the Mid-Atlantic region to close out the work week on Friday, but this will be just the first "step-down" in temperatures in coming days. Another storm system will move quickly from the Rockies this weekend and head towards the Great Lakes region likely producing the first accumulating snow of the season in places like Chicago, Detroit and Madison. This next storm will slide a secondary cold front through here on Saturday night and the coldest air mass of the season will arrive on Sunday. In fact, Sunday promises to be the coldest day of the season so far and snow flurries/snow showers are not out of the question across portions of the Mid-Atlantic and Northeast US (forecast surface map above; blue=snow). Well-below normal temperatures will remain stuck in place across the eastern US on Monday as we begin the new work week (temperature anomaly forecast map below).
[12Z GFS temperature anomaly forecast map for Monday morning; courtesy NOAA, tropicaltidbits.com]
Looking ahead to Turkey Day and beyond
While still chilly next Tuesday, it is likely that the second half of next week will see a turn to milder conditions in the eastern US following this weekend’s cold blast and before another cold blast arrives late in the weekend following Thanksgiving Day. This next cold blast which will arrive near the end of November is likely to be even colder than this weekend’s outbreak.
[00Z GFS Ensemble 2-meter temperature anomaly forecast map for days 1-5; courtesy NOAA, "tropicaltidbits.com"]
So far the month of November has been well above normal in the Mid-Atlantic region (Philly +7.1°, DCA +5.0°, NYC +6.4°), but it looks like the overall mild pattern is going to change noticeably to colder for the last ten days of the month and perhaps right even into early December and all of this is going to be triggered by a heavy rain event on Thursday. After a mild day to start the work week, there will be a temporary setback in the mild temperatures on Tuesday as a back door cold front slides southward through the Mid-Atlantic region during the overnight hours. High temperatures on Tuesday afternoon will be some ten degrees cooler than what is expected later this afternoon. Milder air pushes northward again on Wednesday and Thursday riding in on increasingly strong south-to-southwest winds and a strong cold front will be approaching from the west. Heavy rain is likely from the cold frontal system late Wednesday night and Thursday in the I-95 corridor and this event will trigger the temperature pattern change to colder beginning by this upcoming weekend.
[00Z GFS Ensemble 2-meter temperature anomaly forecast map for days 6-10; courtesy NOAA, "tropicaltidbits.com"]
Last night’s GFS Ensemble run at 00Z shows nicely the changes that are coming not only here to the Mid-Atlantic region for the last ten days of the month, but also to much of the nation as well. The first map (top) shows the overall temperature anomalies across the US for days 1-5 (16NOV-21NOV). Warmer-than-normal conditions (oranges) dominate in the eastern US with mainly colder-than-normal (blues) weather out west during this current 5-day stretch. Beyond that, the 6-10 day (21NOV-26NOV) temperature anomaly forecast map (middle) shows big changes in the Mid-Atlantic region with colder-than-normal (blues) conditions and it is similarly cold throughout most of the nation away from the southwestern states. Does the cold hold beyond that time period? The 11-15 day (26NOV-01Dec) temperature anomaly forecast map (bottom) indicates it certainly will with colder-than-normal weather continuing in most of the nation right from Thanksgiving into the beginning of December. As far as snow is concerned, there are signs for some threats in the Northeast US in the weekend after Thanksgiving or the early part of December and we’ll monitor those chances in the days ahead.
[00Z GFS Ensemble 2-meter temperature anomaly forecast map for days 11-15; courtesy NOAA, "tropicaltidbits.com"]
[Colorized IR satellite image on November 10, 1975; courtesy University of Wisconsin, NOAA]
Forty years ago on November 10th, 1975, a major storm over the Great Lakes helped to sink the SS Edmund Fitzgerald in Lake Superior and all of its 29 crew members died. When launched on June 7, 1958, it was the largest ship on North America's Great Lakes, and she remains the largest to have sunk there. The Edmund Fitzgerald was in the worst possible location during the worst weather of the ferocious storm. The wind and waves from the west hit the freighter broadside as it tried to flee south to safety in Whitefish Bay. The Edmund Fitzgerald was loaded with about 26,000 tons of taconite pellets on Nov. 9, 1975, at Superior, Wisconsin and was bound for Detroit, Michigan.
Storms on the Great Lakes can rival hurricanes in their intensity and the one that sank the Edmund Fitzgerald had sustained winds of 67 mph, gusts up to 86 mph, and waves reported up to 35 feet according to another vessel in the area that survived the storm. On November 8, 1975, a storm was brewing in the center part of the country and it headed northeastward towards the Great Lakes. On November 9 at 7 p.m. the National Weather Service (NWS) issued a gale warning for Lake Superior. The NWS predicted east to northeasterly winds during the night, shifting to NW to N by the afternoon of November 10. At approximately 10:40 p.m., the NWS revised its forecast for eastern Lake Superior to easterly winds becoming southeasterly the morning of the 10th. At about 2:00 am on November 10th the NWS upgraded the gale warning to a storm warning (winds 48-55 knots) with a prediction of "northeast winds 35 to 50 knots becoming northwesterly 28 to 38 knots on Monday, waves 8 to 15 feet".
[Surface map on November 10, 1975]
Around 2 a.m. on the 10th the captains of the Anderson – a second freighter caught in the storm that survived - and Edmund Fitzgerald discussed the threatening weather and decided to change their route. This safer route would take them northward, toward the coast of Canada. The northern route would protect them from the waves that the storm generated. At 3 am, the winds were reportedly coming from the northeast at 42 knots. The Anderson and Edmund Fitzgerald proceeded together with the Edmund Fitzgerald ahead of the Anderson. They had radio contact and the Anderson's radar located the position of the Edmund Fitzgerald. At 7 am onn the 10th, the intensifying storm passed over Marquette, Michigan and it started to move across Lake Superior.
On the afternoon of November 10th, an important wind shift took place. At 2:45 p.m. the winds had backed to NW and were still strong at 42 knots. Steady winds at 43 knots and waves of up to 12 and 16 feet were reported by the Anderson. At around this time, the Edmund Fitzgerald contacted the Anderson and reported "a fence rail down, two vents lost or damaged and a list” (a list is when a ship leans to one side). A shift of winds to the NW is very important, as this increased the fetch allowing large waves to build. The Edmund Fitzgerald and Anderson were no longer protected by land.
Late on the afternoon of the 10th, the captain of the Edmund Fitzgerald made radio contact with another ship, the Avafor, and reported that they "had a bad list, had lost both radars, and was taking heavy seas over the deck in one of the worst seas he had ever been in." Captain McSorely was a seasoned sailor of the Great Lakes with 44 years of experience and this incredibly was to be his final voyage before retirement. At 7 p.m., the Anderson made radio contact with the Edmund Fitzgerald and had her on their radar. When asked how the Edmund Fitzgerald was making out (around 7:10 pm) they replied "we are holding our own". Shortly afterwards the Edmund Fitzgerald disappeared from the Anderson's radar screen. No distress signals were ever issued. The Anderson reported the missing Edmund Fitzgerald to the U.S. Coast Guard. After conducting a heroic, but futile search of the area for survivors, the Anderson entered into the protection of Whitefish Bay from the stormy Lake Superior in the early hours of November 11. The Edmund Fitzgerald sank in 530 feet of water about 17 miles from Whitefish Bay, near the cities of Sault Ste. Marie, Michigan, and Sault Ste. Marie, Ontario.
Gordon Lightfoot’s song “The Wreck of the Edmund Fitzgerald”
The story of the Edmund Fitzgerald was made famous one year later by Canadian songwriter Gordon Lightfoot's song "The Wreck of the Edmund Fitzgerald" (1976, Moose Music, Ltd.). This song was a tribute to the ship wreck and to the men who lost their lives. Some of the lyrics of the song (below) made it sound as though the crew knew they were doomed. In reality, it is believed that the sinking of the Edmund Fitzgerald was very rapid and it is likely they did not know the seriousness of their condition. Indeed, after the wreck a severely damaged life boat was found and only part of the second. The condition of the lifeboats suggests that no attempts were made to leave the ship.
"...At seven p.m. a main hatchway caved in he said 'fellas it's bin good to know ya' The captain wired in he had water comin' in and the good ship and crew was in peril and later that night when 'is lights went out of sight came the wreck of the Edmund Fitzgerald"
More on Great Lakes shipping disasters
Incredibly, in the past 300 years, about 30,000 people have died in 10,000 shipwrecks on the Great Lakes. Other shipping disasters on the Great Lakes, in which weather played a role include: • Nov. 11, 1913: eighteen ships were lost killing 254 people. • Nov. 11-13, 1940: 57 men died when three freighters sank in Lake Michigan. • Nov. 18 1958: 33 men died on Lake Michigan with the sinking of the Carl D. Bradley. • Nov. 29, 1966: Daniel J. Morrell sank in Lake Huron killing the 28 crew members.
[Current SST anomalies with El Nino region circled; data courtesy NOAA, map courtesy "tropicaltidbits.com"]
El Nino conditions developed last year in the equatorial part of the Pacific Ocean and they have intensified significantly in the past several months. In fact, it appears that this El Nino will end up rivaling in strength the comparable events of 1972-1973, 1982-1983 and 1997-1998. This type of natural phenomenon features warmer-than-normal sea surface temperatures in the tropical Pacific Ocean while its counterpart called La Nina is associated with colder-than-normal waters. Given the fact that the Pacific Ocean is by far the world’s largest, it is not surprising that an El Nino of this magnitude is having major ramifications around the world and it will continue to do so for the next several months. Indeed, this El Nino is quite likely to play an important role in the upcoming winter around here in the Mid-Atlantic region: http://vencoreweather.com/2015/10/14/400-pm-2015-2016-winter-outlook-for-the-mid-atlantic-region/. There are some indications that the peak of this current El Nino episode will occur over the next month or two and then it’ll begin to weaken during the early part of 2016. In fact, there are some computer model forecasts that suggest this strong El Nino will completely reverse in a year or so to strong La Nina conditions and this too would have significant consequences around the world.
In the past few months, warmer-than-normal sea surface temperature anomalies (circled orange area in above plot) have spread westward from the west coast of South America into the central equatorial Pacific Ocean. Computer forecast models are in general agreement that this strengthening trend in the El Nino will reach its peak over the next couple of months and then there will be weakening next year. The effects of the current strong El Nino have already been appearing in numerous ways around the world. To begin, the added warmth to the sea surface temperatures in the Pacific Ocean has helped to fuel a very active tropical season in that part of the world. In addition, the Atlantic Basin has actually experienced a below-normal tropical season which is often the result of an El Nino as it tends to increase wind shear across the tropical Atlantic Ocean which, in turn, inhibits tropical storm formation.
In addition to its impact on tropical storm activity, El Nino tends to generate a spike in global temperatures. The plot below of global temperature anomalies is produced by NOAA’s CFSv2 model and the circled areas show the spikes in global temperatures associated with recent El Nino events of 2006-2007 and 2009-2010 as well as the jump caused by the current episode. The spike associated with the current El Nino may continue for the next several months as there is often a lag in the effects of El Nino well past the actual peak in sea surface temperature anomalies. In other words, even if El Nino begins to weaken during early 2016, a residual “warming” effect can still show up for awhile with respect to global temperature anomalies. One other important point to make regarding the global temperature anomaly pattern that is related to El Nino is that in each of the recent El Nino events of 2006-2007 and 2009-2010, global temperatures dropped sharply in subsequent months following the El Nino.
[NOAA CFSv2 global temperature anomalies; courtesy Ryan Maue of Weather Bell Analytics]
Strong La Nina may be just a year away
Some computer forecast models are already predicting the demise of the current El Nino and, in fact, suggest a strong La Nina (colder-than-normal SSTs) will replace it by the end of next year. The plot below is a computer model forecast map from the Scripps Institution of Oceanography and it predicts there will be a strong La Nina event in a year or so in the same tropical region of the Pacific Ocean that is now experiencing well above-normal SSTs. As has been the case with the recent two El Nino events, a reversal like this would quite likely have serious ramifications on global temperatures. It would not be surprising to see another sharp drop in global temperatures once the current strong El Nino event fades away and La Nina conditions return to the tropical Pacific Ocean.
[Scripps Institution of Oceanography forecast map of tropical Pacific Ocean SST anomalies during late 2016 (greens, blues are colder-than-normal water temperatures]
Valley Forge, PA
[Increase in October snowpack across Siberia (white=snowcover, yellow=ice); courtesy US National Ice Center/NOAA]
One of the key reasons provided in the mid-month release of Vencore Weather’s “Winter Outlook” (http://vencoreweather.com/2015/10/14/400-pm-2015-2016-winter-outlook-for-the-mid-atlantic-region/) for the expectation of a snowy winter in DC, Philly and NYC had to do with the fact that there were numerous favorable signs for “high-latitude blocking” this upcoming winter. “High latitude blocking” is an atmospheric phenomenon that can be tracked by meteorologists through an index called the Arctic Oscillation (AO) and it often leads to cold air outbreaks in the Northeast US (usually with a negative index value). Studies have shown that an increase in snowpack across Siberia during the month of October – specifically in areas south of 60°N – is pretty well correlated with persistent negative AO index values in subsequent winter months and “high latitude blocking” events (http://web.mit.edu/~jlcohen/www/papers/Gong_JC03.pdf). This in turn is often correlated with cold air outbreaks in the Northeast US which, of course, is a necessary requirement around here for snow. Indeed, the snowpack across Siberia has increased dramatically from the beginning of October to now – even in those areas south of 60°N. In fact, there are reports that in just the last three days the Siberian snowpack has increased by over 2 million square kilometers (source WxRisk.com).
[Current Northern Hemisphere snowpack (brown=snowcover); courtesy Rutgers Snow Lab]
The top figure compares the snow cover (white region) across Siberia from the end of September to today’s level. There has been a steady increase in snowpack in Siberia over the past few weeks from the mainly snow-free grounds at the beginning of the month. In addition to northern Canada and Greenland, Siberia can be a crucial cold air source for the northeastern states during any given winter season. It is not uncommon for an air mass to build up over a several day period in the wintertime over a snow-packed Siberia and then have it make a move across the North Pole into northern Canada and then eventually into the northern US. The second figure above displays a current view of the snow pack across the Northern Hemisphere and - in addition to Siberia - northern Canada and Greenland are now well covered by snow (brown region; data courtesy Rutgers Snow Lab). (One final note, there is an unofficial report of the lowest October temperature ever recorded in Greenland on 10/24 at -67.72°F).
[Game winning celebration for the KC Royals at the end of Game 1; courtesy MLB, ESPN, Getty images]
The World Series began last night in Kansas City, Missouri and it turned out to be the longest first game in Fall Classic history (14 innings, 5 hours 9 minutes) and there was ample entertainment along the way including a first-pitch inside the park home run for the Royals, a power outage that knocked the telecast off the air, and a game tying home run in the bottom of the ninth inning. The weather started off on the damp and chilly side, but, all in all, it did not play much of a factor in the marathon. This World Series is beginning slightly later than usual and should it go all 7 games, it would not end until Wednesday, November 4th. Despite some chilly weather expected in New York City this weekend for their three home games, the weather looks like it should not become a major issue this year – despite the late start. In fact, should the Series get back to Kansas City next week for games 6 and/or 7, high temperatures are liable to reach the 70’s on either day as a warm weather pattern sets up next week for much of the eastern 2/3rds of the country.
In terms of the coldest World Series games ever (and the records are sketchy pre-1970’s as Major League Baseball did not track weather records), the most memorable game occurred in Game 4 of the 1997 World Series in Cleveland, Ohio between the Indians and the Florida (now Miami) Marlins. The first-pitch temperature for that game was 38 degrees with a wind chill in the teens. Snow flurries fell throughout the game and ice patches actually formed on the infield. The first two games of that Series were played in Miami where temperatures were in the high 80’s. The second coldest game in recent history was the first game of the 1979 World Series in Baltimore, Maryland between the Orioles and Pirates with first-pitch temperatures right around 40 degrees and a steady, chilly rain falling.
Perhaps the most memorable game with respect to weather and the World Series is Game 5 of the 2008 World Series between the Phillies and the Tampa Bay Rays. That game began on October 27th with 50-degree temperatures and a steady rain falling and was suspended in the 6th inning as the rain became too heavy. The game could not be resumed the next day as a powerful nor’easter continued to pound away on the Philadelphia region with a cold, steady rain and even several inches of accumulating snow in nearby Bucks County, PA. Finally, two days after the game began, Game 5 resumed on a cold night in Philly with first-pitch temperatures at 44 degrees along with a gusty northwest wind and the Phillies went on to clinch the title.
Whether these findings are part of normal "year-to-year" variability or indeed part of a long-term trend, the results of a new study are quite interesting. Philip Klotzbach (Department of Atmospheric Science, Colorado State University) and Christopher Landsea (NOAA/NWS/National Hurricane Center) have just published the results of a study in which they conclude shows “large, significant downward trends” in Accumulated Cyclone Energy in the Northern Hemisphere, the Southern Hemisphere and globally during the 25-year period of 1990-2014. In addition, the study has found “small, insignificant” trends in intense (category 4-5) hurricane frequency and percentage in the same 25-year period on a global basis. The results of this study have been published in the October edition of the Journal of Climate: http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-15-0188.1).
Accumulated Cyclone Energy (ACE)
Accumulated Cyclone Energy (ACE) is a commonly-used metric for tropical activity because it is not dependent on exact numbers of named storms or hurricanes, but rather is based on both the intensity and longevity of all tropical storms and hurricanes (so a long-lived tropical storm could contribute as much ACE as a short-lived storm that reached hurricane intensity). The figure below from the Klotzbach and Landsea journal article displays the ACE levels for the 45-year period from 1970 through 2014. The top half of the figure displays ACE by year for each of the six global tropical cyclone basins since 1970. These values are combined into hemispheric and global sums in the bottom half of the figure. There has generally been a decreasing trend in ACE since the early 1990s when a prolonged El Nino event enhanced activity in the North Pacific.
[Accumulated Cyclone Energy (ACE) 1970-2014; courtesy Klotzbach and Landsea (1 October 2015, Journal of Climate)]
This year’s tropical activity
In terms of ACE for 2015, it has been very active in the Pacific Ocean aided in large part by a strong El Nino event (warmer-than-normal water) in the tropics. Indeed, the ACE values are well above normal in both the western North Pacific and the eastern/central North Pacific (table below; data courtesy Ryan Maue of Weather Bell Analytics; http://models.weatherbell.com/tropical.php). On the other hand, the Atlantic Ocean has actually been below normal with respect to ACE and that is partly due to the same El Nino event that has helped to fuel Pacific Ocean tropical storms. Evidence shows that in El Nino years, there is an added level of wind shear in the tropical Atlantic Ocean which tends to inhibit tropical storm formation. The downturn in Atlantic Basin tropical activity during 2015 has helped keep alive a 10-year drought in the US with respect to major hurricane (categories 3, 4 and 5) strikes. In fact, we have just passed the 10-year anniversary for the last major hurricane landfall in the US (Wilma in Florida, October 2005) which is the longest drought ever logged in the record-keeping era.
[2015 Accumulated Cyclone Energy (ACE) on a global basis; data courtesy Ryan Maue, Weather Bell Analytics]
Looking ahead to the tropics
There is a word of caution for the US, however, as this year’s strong El Nino event in the tropical Pacific Ocean is quite likely to weaken during 2016 and the “beneficial” effect of higher-than-normal wind shear in the Atlantic Basin is likely to diminish by next summer potentially leading to an uptick in activity. In fact, this potential increase in Atlantic tropical activity next year could even extend into 2017 as La Nina conditions (colder-than-normal waters) are quite possible by that time in the tropical Pacific Ocean. Meanwhile, it is entirely possible that at the same time the Atlantic Ocean tropical activity potentially increases during the next couple of years, the Pacific Ocean could experience somewhat quieter conditions compared to today as sea surface temperatures drop relative-to-normal with the gradual demise of El Nino.
[Visible satellite image of Hurricane Patricia shortly after sunrise; courtesy NASA]
Hurricane Patricia intensified explosively yesterday from a category 1 storm early in the day to a category 5 level by early today - perhaps reaching the strongest levels ever seen during the record-keeping era in the eastern Pacific Ocean in terms of central pressure (880 mb or 25.98 inches) and wind speeds (maximum sustained winds near 200 mph). It is likely to make landfall later today somewhere between Puerto Vallarta and Manzanillo with 185 mph wind gusts possible along with torrential rainfall.
Fueled by one of the strongest El Nino events since 1950, Patricia has become the 9th hurricane in the eastern Pacific to achieve at least category 4 or 5 intensity, which is the most during the record-keeping era. The storm has been able to achieve incredible intensification by developing over some of the warmest ocean temperatures in the Northern Hemisphere, over 86 degrees. In fact, the “boxed-in” region on the sea surface temperature plot (below) has water temperatures that average 1°C higher than at any time in the last 34 years (source: Ryan Maue of WeatherBell Analytics).
[Sea surface temperature analysis of eastern Pacific Ocean region (dark brown region is 86-87 degrees F); source Weather Bell Analytics]
According to the National Hurricane Center, early this morning Patricia became the strongest hurricane recorded for the eastern Pacific and Atlantic Ocean. The estimated central pressure of Patricia dropped to 880 mb, breaking the record of 894 mb from Hurricane Linda in the eastern Pacific set in 1997 and also surpassing the 882 mb pressure of Hurricane Wilma in the Atlantic from 2005. The maximum sustained winds of 200 mph (160 knots) breaks the previous wind speed record from Linda and Wilma (185 mph) for the strongest surface winds ever in the area of responsibility of the National Hurricane Center.
[Colorized IR image of Hurricane Patricia from early today; courtesy NOAA, NASA]
While significant weakening will occur after the center of Patricia heads inland, copious amounts of moisture will head northeastward across Mexico bringing flooding along its path this weekend. By late in the weekend, the remains of Hurricane Patricia will head into the Texas/Louisiana section of the Gulf coastal region in the US bringing heavy rains and strong winds. The moisture is then likely to get caught up in a frontal system early next week across the Mississippi and Ohio Valleys and it could generate widespread heavy rainfall and even a significant severe weather outbreak. By the middle of next week, this system and its moisture field will likely arrive in the Mid-Atlantic region.