Snowiest Winter on Record in Portions of Michigan and Ohio

Figure 1. Predicted temperatures for March 20 - 26, 2014, from NOAA's Climate Prediction Center show a continuation of much colder than average temperatures over the Midwest and Northeast U.S.

The relentless winter of 2013 - 2014 continues to add to its extraordinary resume over the Eastern U.S., where yet another near-record cold blast is underway. Temperatures on Thursday will be 10 -25° below normal over the eastern 1/3 of the country, and it will be a serious case of weather 
whiplash in places like New York City, where the temperature peaked at 65°F at JFK Airport on Tuesday, a record high for the date. Temperatures will struggle to reach the upper-20s on Thursday--a spectacular 40° swing, and one of the coldest high temperatures so late in the year.
 The weather pattern that brought this winter's persistent cold to the Midwest and Eastern U.S., and record warmth and drought to the West Coast, is going to remain in place through most of the remainder of March. The latest 16-day forecast from the GFS model predicts a continuation of the dominant ridge over the Western U.S. and trough over the Midwest and Eastern U.S. that we've all grown very, very, very tired of (said Dr. Masters, after shoveling the latest installment of 6.5" of 
-like snow of this winter's 90.7 inches that have fallen in the Detroit area--second only to the 93.6" that fell in the winter of 1880 - 1881.)
 Detroit has now had over 1" of snow on the ground for 72 consecutive days, and will easily break the record of 74 straight days, set during the notorious winter of 1978. Just to the south, in Toledo, Ohio, and Fort Wayne, Indiana, Wednesday's dumping of 6.7 - 7" of snow from Winter Storm Vulcan made the winter of 2013 - 2014 the snowiest on record at both cities. Chicago's 3.2" brought the winter total to 79.1", making it the Windy City's 3rd snowiest winter (the record: 89.7" in 1978 - 1979.) Some major cities that have had a top-five snowiest winters on record during 2013 - 2014
http://www.wunderground.com/blog/JeffMasters/archive.html?year=2014&month=03

Winter of 2013 - 2014: Top-10 Coldest in Midwest; Warmest on Record in California

Figure 1. Perhaps the most iconic image of the U.S. winter of 2013 - 2014: Traffic gridlock in Atlanta on Tuesday afternoon, January 28, 2014 after Winter Storm Leon brought 2.6" of snow, shutting down the city. Image credit: @beercontrol/twitter.
The winter of 2013 - 2014 will go down in the history books in the Midwest U.S. as a top-ten coldest winter on record, but ranked as the warmest winter on record in California. Temperatures averaged over December 2013 - February 2014 in the contiguous U.S. made it our 34th coolest winter since 
records began in 1895, said NOAA's National Climatic Data Center (NCDC) in their latest State of the Climate report. The last winter that was colder was 2009 - 2010, which ranked 15th coolest. For comparison, the winter of 2012 - 2013 was the 20th warmest, and the "non-winter" of 2011 - 2012 was the 4th warmest. Seven states had a top-ten coldest winter on record in 2013 - 2014: Wisconsin, Minnesota, Iowa, Missouri, Illinois, Indiana, and Michigan. 
Three states had a top-ten warmest winter on record: California, Arizona, and Alaska. The Southwest had an unusually dry winter, with California, Arizona, New Mexico, and Texas all recording top-ten dryness. For the nation as a whole, it was the 9th driest winter on record. The winter average snow cover extent for the contiguous U.S. was the 10th largest since record keeping began in 1966.
The U.S. winter of 2013 - 2014 had the 25th highest level of extremes observed since 1910, thanks primarily to the spatial extent of cold maximum and minimum temperatures and days with precipitation, according to NOAA's U.S. Climate Extremes Index (CEI). The index tracks the percentage area of the contiguous U.S. experiencing top-10% and bottom-10% extremes in temperature, precipitation, and drought. For the Western U.S. (California and Nevada), it was the 
most extreme winter on record, primarily because 84% of the region experienced top-10% dryness. 
http://www.wunderground.com/blog/JeffMasters/archive.html?year=2014&month=03

California's Rainy Season Almost Over

Figure 1. Predicted precipitation for the 7-day period ending on Tuesday, March 25, 2014. No rain is expected to fall in California in the coming week. Image credit:NOAA/HPC.
The California rainy season is close to its end. Rain-bearing low pressure systems typically stop bringing heavy rains to the state by mid-April, as the jet stream shifts to the north in its usual springtime migration. With no rain in the forecast for the next seven days, and the 16-day GFS forecast showing mostly light rains affecting the northern portion of the state 8 - 16 days from now, California has likely seen at least 90% of the precipitation that it’s going to get this anemic rainy season. 
That’s a huge concern for a state suffering through its worst winter drought conditions in recorded history, and Sierra snow pack and reservoir levels near record lows. This year’s drought could well be a harbinger of the future, as climate change is expected to cause increased water availability problems in California. The state is going to have to find new sources of water in the future to support its growing population. Where can California find more water?
The most feasible way for California and the thirsty Southwest U.S. to get more water is through conservation. Irrigated agriculture currently consumes more than 70% of the water supply within the Colorado River basin, and is the obvious first place to look to implement water-saving conservation measures. A 2013 publication by the Pacific Institute, "Water to Supply the Land: Irrigated Agriculture in the Colorado River Basin", offers a number of common-sense ways agriculture could use Colorado River water more efficiently. The river's annual flow is about 15 million acre-feet (an acre-foot is the amount of water needed to cover an acre of land to a depth of one foot.) One-third of the Colorado River's annual flow, about 5 million acre-feet, is devoted to irrigating pasture, alfalfa (hay), and other forage crops used to feed cattle and horses. Alfalfa, planted extensively from Wyoming to the delta in Mexico, covers more than a quarter of the total irrigated acreage in the basin.Almost 7% of the river's flow (1 million acre-feet) might be saved by irrigating alfalfa less often (a practice known as “regulated deficit irrigation”). This process reduces crop yields by about 25%, and 
thus this process costs approximately $81 per acre-foot of water saved. 
According to Dr. Peter Gleick, President of the Pacific Institute, farmers in Southern California's Imperial Irrigation District are charged as little as $22 per acre-foot of Colorado River water, so some incentives would have to be offered to farmers to get them to implement this water savings plan. (The $22/acre-foot price is an amazingly good deal for a commodity so precious. For comparison, water pumped from rivers in Northern California to Southern California is priced at over $1500 per acre-foot.) 
http://www.wunderground.com/blog/JeffMasters/archive.html?year=2014&month=03

Meteorological Bomb Brewing for Canada on Wednesday

Figure 1. Wind forecast for 5pm EDT Wednesday March 26, 2014, made from the 2am EDT 

Monday, March 24, 2014 run of the GFS model. Winds in excess of 50 knots (57.5 mph, pink colors) 

are predicted along the coasts of Nova Scotia and Newfoundland, Canada.

The most powerful Nor'easter of the year will gather strength over the waters offshore of Virginia on 

Tuesday, then head northeast and bring damaging winds, heavy rain and snow, and a substantial storm surge to Nova Scotia and Newfoundland Canada on Wednesday. The storm will brush Cape Cod, Nantucket, and Martha's Vineyard, Massachusetts on Tuesday night and Wednesday morning, bringing at least six inches of snow and wind gusts of up to 60 mph. A Blizzard Watch and Coastal Flood Watch are posted for Cape Cod and Nantucket Island, where a NOAA storm surge model run using the winds from the 00Z run of the GFS model predicted almost a 2 foot surge could occur on Wednesday morning. 

A surge of this magnitude is capable of causing minor to moderate flooding.

As the storm pulls away from the Mid-Atlantic coast on Tuesday evening, it will undergo explosive 

deepening, meeting the criteria of a "meteorological bomb"--a storm that deepens by at least 24 mb in 24 hours. In fact, the Monday morning 00Z run of the European model shows the pressure falling by more than double that pace--deepening by an extraordinary 40 mb in just eighteen hours, ending at 2 

pm EDT Wednesday. When the Nor'easter hits Nova Scotia and Newfoundland on Wednesday evening, the central pressure of the storm is expected to be between 956 - 960 mb, similar to the central pressure of a strong Category 2 hurricane. 

However, Nor'easters do not form eyewalls with intense winds concentrated over a small area, and this Nor'easter's strong winds will be spread out over a large area. I doubt we'll see sustained hurricane-force winds of 74 mph or greater at any land stations, but sustained winds of 60 - 70 mph are likely in some locations, which will be capable of causing widespread power outages and considerable tree damage. A storm surge of 2 - 4 feet may also cause coastal damage and moderate flooding, if the surge arrives at high tide.

http://www.wunderground.com/blog/JeffMasters/archive.html?year=2014&month=03

Washington Landslide Death Toll Grows to 14

Figure 1. The Oso, Washington area before the March 22, 2014 landslide as seen onGoogle Earth (top) and after the landslide, as photographed by the Washington Department of Transportation (bottom.) The landslide blocked the North Fork of the Stillaguamish River and Highway 530. 
The death toll has grown to fourteen from Saturday's massive landslide near Oso, Washington, located about 50 miles north-northeast of Seattle. At least seven were injured, and 176 are listed as missing, though this total is likely to decrease dramatically as missing people check in. The landslide was triggered by unusually heavy rains over the past 30 days in the region.
 A personal weather station located about ten miles west of the slide recorded 13.81" of precipitation in the 30 days prior to the slide, including 5.17" in the ten days just before. Precipitation imagery from NOAA's Advanced Hydrological Precipitation Service (Figure 2) shows that the 30-day precipitation amounts in the region were more than 8" above average--about double the usual amount 
of rain for this time of year. 
According to Dave Petley, Professor of Hazard and Risk in the Department of Geography at Durham University in the United Kingdom, it is clear that major landslides have occurred here on many previous occasions, so much so that the landslide is known as either the Hazel landslide or the Steelhead landslide. In his excellent Landslide Blog, my go-to source of information for any landslide, he writes:"The landslide has been widely reported as a mudslide. In terms of the lower portion, which did the damage, this is correct, although in places it might have been more of a mudflow than a mudslide. However, the upper portion is a rotational landslide–the rotated block with the fallen trees is very clear. A working hypothesis would be that this block failed catastrophically, transferring load onto the block below, which in turn generated very high pore water pressures, 
causing fluidisation and a very rapid mudflow that struck the settlements across the river." 
He writes that the last event on a similar scale he knows of was the 25th December 2003 debris flow in San 
Bernadino County, California, which killed sixteen people. Weather historian Christopher C. Burthas a post about the worst landslides in U.S. history, which puts this week's landslide in context.
http://www.wunderground.com/blog/JeffMasters/archive.html?year=2014&month=03

Mighty 955 mb Nor'easter Pounds Canadian Maritime Provinces

Figure 1. True-color MODIS satellite image taken at approximately 2pm EDT Wednesday March 26, 2014, of the powerful Nor'easter affecting Canda's Maritime provinces. At the time, the storm had a central pressure of 955 mb, and was generating winds over the water of Category 1 hurricane strength (at least 74 mph.) Image credit: NASA.
The strongest Nor'easter of 2014 blasted Prince Edward Island, New Brunswick and Nova Scotia on Wednesday with wind gusts over 100 mph and up to a half meter (19.5") of snow, bringing travel to a standstill and causing power outages that affected about 17,000 customers in Nova Scotia.

 The mighty storm intensified rapidly on Wednesday afternoon, "bombing" to a central pressure by 2pm EDT of 955 mb--similar to the central pressure of a Category 3 hurricane. The storm's pressure fall of 45 mb in 24 hours is among the greatest on record for a Nor'easter (for comparison, the 1978 Cleveland Superbomb had a pressure drop of 43 millibars in 24 hours, also to 955 mb.) The La Have Bank buoy south of Halifax, Nova Scotia measured a pressure of 957 mb as the center of the storm passed nearby, along with significant wave heights of 29 feet. 

A wind gust of 129 mph was measured on Wednesday at the Bay of Fundy, and sustained winds of 89 mph with a gust to 115 mph was recorded between 6:30 - 7:30 pm EDT in Wreckhouse, Newfoundland, beating the previous strongest gust of 112 mph set in 2007 (Wreckhouse is named for the terrain-enhanced winds that often cause destruction.) Grand Étangon the Gulf of St Lawrence side of Cape Breton in Nova Scotia recorded top sustained winds of 70 mph, gusting to 102 mph. 
This location is susceptible to strong "Les Suêtes" winds in this type of setup--"Suêtes" is a dialectal corruption of French "sud-est," or "southeast". These southeasterly winds travel up over Cape Breton and a funneling effect intensifies them as they blow downslope toward the Gulf of St Lawrence. As a result, these gusts are not truly representative of the storm, but rather the storm plus local terrain effects. Environment Canada has a special "Les Suêtes Wind Warning", and issued it for Wednesday's storm.
http://www.wunderground.com/blog/JeffMasters/archive.html?year=2014&month=03

Can Cloud Seeding Help Ease California's Drought?

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Figure 1. Predicted precipitation for the 7-day period ending on Friday, April 4, 2014. Much needed rains and snows are expected to fall in California in the coming week. Image credit: NOAA/HPC.

 The California rainy season is bringing one final blast of moisture to the drought-parched state over the coming week. Strong low pressure systems will bring mountain snows and valley rains to most of 

the northern half of the state on Saturday and again on Monday, and widespread precipitation amounts of 4+ inches are likely. 
A Winter Storm Watch is posted for the Sierras, where snowfall amounts of 1 - 2 feet are expected over the weekend. Monday's storm will likely dump another 1 - 2 feet, providing a critical boost to a drought-depleted snowpack that the state desperately needs to provide water during the hot, dry summer months. Rain-bearing low pressure systems typically stop bringing heavy rains to the state by mid-April, as the jet stream shifts to the north in its usual springtime migration. The 16-day GFS forecast is showing one more decent shot of moisture is possible on April 4, then a shift to a drier pattern will occur.
 The March 25, 2014 Drought Monitor is showing that 99.8% of California is in drought, with 95% of the state in Severe, Extreme, or Exceptional drought, a 2% rise from the previous week.
http://www.wunderground.com/blog/JeffMasters/archive.html?year=2014&month=03

Dangerous Category 4 Hellen Nears Madagascar

Figure 1. True-color MODIS satellite image of Tropical Cyclone Hellen nearing Madagascar at 12 
UTC March 29, 2014. At the time, Hellen was a Category 4 storm with 150 mph winds. Image credit: NASA.
Extremely dangerous Category 4 Tropical Cyclone Hellen is bearing down on Madagascar after an extraordinary burst of rapid intensification brought the cyclone from a 60 mph tropical storm to a high-end Category 4 storm with 150 mph winds in just 24 hours. That 90 mph increase in winds in 24 hours is not far below the record intensification rate of Hurricane Wilma in 2005, which was 110 mph in 24 hours. Officialbulletins from La Réunion indicate the central pressure dropped 61 mb in 24 hrs, from 986mb at 1800 UTC Saturday to 925mb at 1800 UTC Sunday. They warn in their 18 UTC Sunday advisory:HELLEN IS LIKELY TO BE ONE OF THE MOST POWERFUL TROPICAL CYCLONES EVER SEEN OVER THE NORTHERN CHANNEL SINCE THE SATELLITE ERA (1967). THE 
LIKELIHOOD IS INCREASING FOR AN EXTREMELY DANGEROUS TROPICAL CYCLONE LANDFALL OVER THE NORTHWESTERN COASTLINE OF MADAGASCAR BETWEEN 
CAPE SAINT-ANDRE AND MAHAJONGA. THE RSMC TROPICAL CYCLONE STORM SURGE NWP HAS BEEN RUN AND SHOWS PHENOMENAL SEA ELEVATIONS IN THE AREA EXPOSED TO THE NORTHERLY WINDS (EAST OF THE FORECAST TRACK). THE STORM SURGE COULD REACH 2 - 4 METERS (7 - 13 FEET)
 IN THE ESTUARY OF THE BETSIBOKA RIVER (MAHAJONGA), AND MORE THAN 7 
METERS (23 FEET) IN THE BAY OF BALY (SOALALA), AND 1 - 4 METERS ON THE COASTLINE EAST OF CAPE SAINT-ANDRE. ALL PREPARATIONS FOR A "WORST CASE" 
SCENARIO SHOULD BE UNDERWAY.
http://www.wunderground.com/blog/JeffMasters/archive.html?year=2014&month=03

IPCC: Climate Change Increasing Risk of Hunger, Thirst, Disease, Refugees, and War

Climate change is already having "widespread impacts", and has the potential to worsen global hunger, water availability, disease, drought, flooding, refugees, and war in the coming decades if we do nothing to reduce it, said the Intergovernmental Panel on Climate Change (IPCC) today, in the latest installment of their once-every-seven-year report on the climate.Today's report on climate change impacts and how we can adapt to them warned that "throughout the 21st century, climate-change impacts are projected to slow down economic growth, make poverty reduction more difficult, further erode food security, and prolong existing and create new poverty traps."
 Today's report by the Nobel-prize winning group of scientists was the second of four parts. Part 1, released in September 2013, covered the physical science behind climate change. Part 3 (due out in mid-April, 2014) will discuss how we can mitigate (reduce) climate change impacts. Part 4 (due out in early November, 2014) will present a grand summary of Parts 1, 2, and 3. Some key themes from today's report:Food supplies will tighten. To me, the most important finding of the report is the climate change's threat to reduce global food supplies, which have already been negatively impacted, and are at risk to get much worse: “Based on many studies covering a wide range of regions and crops, negative impacts of climate change on crop yields have been more common than positive impacts. Climate change has negatively affected wheat and maize (corn) yields for many regions and in the global aggregate."
 For the future, the report acknowledges that some areas will likely see increases in food production, due to increased CO2 in the air and more favorable precipitation, but the overall global trend in food supplies will likely be downward (Figure 1.) This downward trend in yields will occur in the face of rapidly increasing demand, as the population grows by 2 billion, resulting in "increased likelihood of under-nutrition resulting from diminished food production in poor regions."
http://www.wunderground.com/blog/JeffMasters/archive.html?year=2014&month=03

Two-day U.S. Tornado Outbreak Kills at Least 29 People; More Tornadoes Expected Today

 
A swarm of deadly and devastating tornadoes ripped through the Southeast U.S. on Monday, killing at least 13 people, bringing the two-day death toll from this week’s tornado outbreak to at least 29. Hardest hit were Mississippi and Alabama, which lay in the bullseye of the High Risk” area for severe weather issued by NOAA’s Storm Prediction Center early that afternoon. It was the second consecutive day a “High Risk” outlook had been issued by SPC, and the threat of strong and deadly tornadoes continues again on Tuesday, with a “Moderate Risk” of severe weather expected over Alabama and Mississippi. 
The tornado activity in Mississippi and Alabama on Monday was remarkably violent and long-lasting; Alabama’s first tornado warning was issued at 12:37 pm CDT, and the last was nearly sixteen hours later, at 4:20 am (thanks to wunderground member sar2401 in Alabama for this info.) Mississippi suffered the highest death toll on Monday, with eight killed.
 Three people died in Alabama, including a University of Alabama swimmer who died saving his girlfriend from a collapsing building. Two other people died in Lincoln County, Tennessee, near the border with Alabama. In all, for the 24-hour period beginning at 8 am Monday, SPC logged 64 preliminary tornado reports from five states, along with 135 reports of damaging winds and 49 reports of hail. An additional 33 preliminary tornado reports came on Sunday, bringing the two-day preliminary tornado total to 97. 
Hardest hit on Sunday was Arkansas, where fifteen people died in tornadoes. Mayflower and Vilonia, Arkansas, located about fifteen miles northwest and north of Little Rock, had ten people killed by a tornado that has been preliminarily rated as at least an EF-3 by the National Weather Service. Sunday tornadoes also killed one person in Iowa and one in Oklahoma. 
http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=2672

Earth Day 2014 Wunderphoto Selections

Figure 1. My favorite wunderphoto of the past year, "The Green Heaven", was taken on October 31, 2013 in Senja, northern Norway, by wunderphotographer Altred. It's the background image on my laptop.
Today is Earth Day, a day to celebrate the beauty of the atmosphere, oceans, and biosphere of the planet that sustains us. As is my tradition on Earth Day, I present my favorite wunderphotos uploaded to our web site over the past year. 
I want to thank everyone who has participated in making this the largest (1.7 million!) and best weather photo gallery on the Internet--your photos are truly an inspiration! Many of my choices were taken from our Worldview Gallery, updated weekly with the top wunderphotos of the week
http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=2668

One billion-dollar weather disaster in March 2014: Drought in Brazil

One billion-dollar weather-related disaster hit the Earth during March 2014: Southeastern Brazil's worst drought in 50 years, which has cost at least $4.3 billion so far this year, according to the March 2014 Catastrophe Report from insurance broker Aon Benfield. 
This is the third most expensive natural disaster in Brazil's history, and the second consecutive year of disastrous drought in the country. Drought in Northeast Brazil during the first five months of 2013 caused an estimated $8 billion in damage--Brazil's second most expensive natural disaster in recorded history. 
According to the international disaster database EM-DAT, Brazil's costliest natural disaster was the 
drought of 1978 ($2.3 billion in 1978 dollars, or $8.3 billion 2014 dollars.) 
http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=2669

Tornado and severe weather outbreak continues on Monday and Tuesday 4/28/2014

Figure 4. Severe weather outlook for Monday, April 28, 2014, as issued on Monday by NOAA's  
Storm Prediction Center. 
The strong, slow-moving low pressure system that brought this weekend’s deadly tornadoes will spawn spawn more supercell thunderstorms capable of generating large hail, damaging winds, and a few strong tornadoes on Monday. NOAA's Storm Prediction Center (SPC) has issued their "Moderate Risk" forecast of severe weather over much of Mississippi, central and northern Alabama and west and central Tennessee. 
The risk of severe weather will diminish on Tuesday, but most of the Southeast U.S. will be in SPC’s “Slight Risk” region for severe weather. Wednesday will see additional severe thunderstorms along the Southeast U.S. coast, and the severe threat will finally end Wednesday night as the storm responsible moves off the coast. 
http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=2671

Tornadoes and Thunderstorms in Arkansas

Figure 3. Doppler velocity image of the supercell thunderstorm that hit Vilonia, Arkansas tornado. Note the clump of green colors lying right next to orange and red colors over Vilonia, showing that winds moving both towards the radar and away from the radar were located in close proximity to each other, the signature of a rotating mesocyclone in a severe thunderstorm capable of spawning a strong tornado.

The Arkansas Department of Emergency Management said three people also died in Arkansas’ Pulaski County and one in White County from tornadoes on Sunday. NOAA's Storm Prediction Center (SPC) had put much of Arkansas in their “High Risk” area for potential severe weather yesterday. It was the first “High Risk” outlook issued by SPC in 2014. According to The Encyclopedia of Arkansas History and Culture, the deadliest outbreak in Arkansas history occurred on March 21, 1952, when 112 people lost their lives. The most deadly recent outbreak was on March 1, 1997, which resulted in 25 Arkansas fatalities. 

Outside of Arkansas, a tornado hit Quapaw, OK on Sunday, killing one person and destroying the fire station. In Kansas, the governor declared a state of emergency for Baxter Springs, where a tornado destroyed 70 homes and 20 businesses. In all, SPC logged 31 preliminary tornado reports from five states on Sunday, 107 reports of damaging winds, and 118 reports of hail. Also on Sunday, an 11-month old died from injuries suffered during a tornado on Friday in Chowan County, North Carolina. It was the first U.S. tornado death of 2014. 
http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=2671

Arctic sea ice falls to 5th lowest March extent on record

Figure 2. Regions most at risk of severe weather for the period Saturday, April 26 - Monday, April 28, 2014, as predicted by NOAA's Storm Prediction Center at 4:15 am EDT Wednesday, April 23, 2014.
Arctic sea ice extent during March was 5th lowest in the 36-year satellite record, according to  theNational Snow and Ice Data Center (NSIDC). The winter maximum extent of Arctic sea ice came on March 21, and was the 5th lowest such peak on record. Temperatures in the Arctic were 2 - 6°C (4 -11°F) above average during the last half of the month, but a late-season surge in ice extent came as the Arctic Oscillation turned strongly positive the second week of March, with unusually low sea level pressure in the eastern Arctic and the northern North Atlantic. 
The associated pattern of surface winds helped to spread out the ice pack, keeping ice extent greater than it would have been. There was a modest increase in thick, multi-year ice over the winter, and the Arctic is in better shape to resist a record summer melt season this year than it was in 2013.
http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=2669

El Niño watch continues

Figure 2. The deadliest U.S. weather disaster of March 2014 was the tragic landslide at Oso, Washington that killed 41 people and did $10 million in damage. The landslide was triggered by record March rains that saturated the soils. The nearby Seattle airport measured 9.44” (240 mm) of precipitation in March, a new record for the month. Photo by Washington State Patrol. 
March 2014 featured neutral El Niño conditions in the equatorial Eastern Pacific, but NOAA has issued an El Niño Watch for the summer and fall of 2014, giving a greater than 50% chance that an  El Niño event will occur by the summer. The April 10 El Niño discussion from NOAA's Climate Prediction Center noted that "there remains considerable uncertainty as to when El Niño will develop and how strong it may become. This uncertainty is amplified by the inherently lower forecast skill of the models for forecasts made in the spring." None of the El Niño models (updated in mid-April 2014) predict La Niña conditions for peak hurricane season, August-September-October 2014, and 16 of 20 predict El Niño conditions. 
Temperatures in the equatorial Eastern Pacific need to be 0.5°C above average or warmer for three consecutive months for an El Niño episode to be declared; sea surface temperatures were +0.2°C from average as of April 21. El Niño conditions tend to make quieter than average Atlantic hurricane seasons, due to an increase in upper-level winds that create strong wind shear over the Tropical Atlantic. There is currently a Westerly Wind Burst (WWB) over the equatorial Pacific Ocean that is helping push warm water eastwards towards South America. If this Westerly Wind Burst persists and expands eastwards through early May, the odds of an El Niño event will increase.
http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=2669

Earth has its 4th warmest March on Record:weekend severe weather outbreak coming

March 2014 was the globe's 4th warmest March since records began in 1880, according to NOAA'sNational Climatic Data Center (NCDC) and NASA. March 2014 global land temperatures were the 5th warmest on record, and global ocean temperatures were also the 5th warmest on record. The year-to-date January - March period has been the 7th warmest on record for the globe. Global satellite-measured temperatures in March 2013 for the lowest 8 km of the atmosphere were 11th or 9th warmest in the 36-year record, according to Remote Sensing Systems and the University of Alabama Huntsville (UAH), respectively. Northern Hemisphere snow cover during March was the 6th lowest in the 48-year record. Wunderground's weather historian, Christopher C. Burt, has a comprehensive post on the notable weather events of March 2014 in his March 2014 Global Weather Extremes Summary.
 Figure 1. Departure of temperature from average for March 2014, the 4th warmest March for the globe since record keeping began in 1880. Much of Europe had a top-five warmest March, including Austria (2nd), Norway (3rd), Denmark (4th), Germany (3rd), Latvia (3rd), the Netherlands (3rd), and Slovakia (1st.) In the U.S., Vermont had its coldest March on record, and Michigan, New York, Maine, and New Hampshire all had top-five coldest Marches on record. Image credit: National Climatic Data Center (NCDC) .
http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=2669

Weekend tornado and severe weather outbreak coming for the Plains

A multi-day severe weather event is expected Saturday, Sunday, and Monday across the Central U.S., as a strong low pressure system will spawn supercell thunderstorms capable of generating large hail, damaging winds, and a few strong tornadoes. The most dangerous day appears to be Sunday, and NOAA's Storm Prediction Center (SPC) has issued their "Moderate Risk" forecast of severe weather over portions of Arkansas , Oklahoma, Texas, and Louisiana that day.
 The action will begin Saturday afternoon along a swath from Central Texas northwards into Oklahoma and Kansas, but at present, Saturday's threat warrants only a "Slight Risk" classification from SPC. This weekend's severe weather outbreak has the potential to be the most dangerous one of this relatively quiet 2014, which has yet to spawn a killer tornado. 
The relatively cool and dry weather across Tornado Alley so far this year has led to no EF-3 or stronger tornadoes as of April 24, which is a record-long wait since modern tornado records began in 1950. 
According to tornado historian Tom Grazulis' book, Significant Tornadoes 1680-1991, "serious efforts" to document all tornadoes began in 1953, which was the first full year of tornado watches issued by the U.S. Weather Bureau, now the National Weather Service.

http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=2670

More tornado strikes may occur in mobile home parks

It's well-known that one should avoid mobile homes during a tornado, as their relatively flimsy construction and tendency to roll when exposed to high winds leads to numerous deaths each tornado season. The majority of tornado deaths occur in mobile homes for this reason, but tornado experts have long wondered why mobile home parks seem to get disproportionately more tornado strikes than other residential areas. New research by Purdue University researchers Olivia Kellner and Dev Niyogi suggests that "transitions zones"--areas where dramatically different landscapes meet, like where a city fades into farmland, or a forest meets a plain--are more prone to tornado touch downs. Since mobile home parks are often located at the edge of built-up areas, they may actually get hit more often.
Figure 1. Damage to 2-year-old C.J. Martin's mobile home park near Evansville, Indiana due to a November 6, 2005 tornado. Twenty people. including C.J., died in the F3 tornado that devastated his Eastbrook Mobile Home Park in Evansville. The storm hit at 2am, when many residents were asleep and didn't hear the tornado sirens. C.J.'s mother, Kathryn Martin, pushed lawmakers to adopt a bill requiring all mobile homes in Indiana to have a weather radio with a tone alert system, which could have saved many lives in the mobile home park that night. C.J.'s Law was signed into law by Indiana governor Mitch Daniels later that year. Image credit: Paducah, KY NWS.The researchers studied where tornadoes touched down in Indiana between 1950 and 2012, and found that 61% of tornado touchdowns occurred within 1 kilometer (about 0.62 mile) of urban areas, and 43% fell within 1 kilometer of forest. Kellner said the percentages suggest that certain locations may increase the likelihood of tornado touchdowns due to increased "surface roughness"--an abrupt change in the height of land surface features, which can stretch or squash a column of air, increasing its rate of spin, which could contribute to the formation of tornadoes. 
Forecasters and city planners may need to pay closer attention to these "transition zones" to better understand tornado risks, said Olivia Kellner, doctoral student in the Department of Earth, Atmospheric and Planetary Sciences in a press release."
There are still many unanswered questions about tornado climatology, but what we're finding  is that  there may be a relationship between the Earth's surface and the atmosphere that      contributes to  where tornadoes tend to touch down." The study also found that tornado touchdowns in urban areas tend to occur at about 1 and 10 miles from the city center. Kellner said these "rings" of   increased tornado activity could be related to how cities are developed. "Cities impact the surrounding climate in terms of regional airflow and temperature," she said. "The size of cities, what they're made of and the heat they produce are factors that could affect the microclimate." 
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Tornadoes kill 16 in Arkansas Oklahoma iowa

The quiet 2014 severe weather season turned grimly violent over the weekend, as multiple deadly tornadoes ended our record-long start to a year without a tornado fatality. Media reports put Sunday's death toll at 16, with 164of deaths in Arkansas, one in Iowa, and one in Oklahoma. Hardest-hit were Mayflower and Vilonia, Arkansas, located about fifteen miles north of Little Rock.
 A large and powerful tornado that had been on the ground nearly an hour carved through the region near sunset, killing at least ten people. Damage photos appeared to show at least EF-3 type damage, and there was a report from relayed from amateur radio to the NWS that two homes in Vilonia had been “wiped clean to the foundation”, which would imply higher than EF-3 damage. 
There has been only one known F5 tornado in Arkansas history, on April 10, 1929. Vilonia was hit just three years ago, on April 25, 2011, by an EF-2 tornado that killed four people. The Arkansas Department of Emergency Management said three people also died in Arkansas’ Pulaski County and one in White County from tornadoes on Sunday. NOAA's Storm Prediction Center (SPC) had put much of Arkansas in their “High Risk” area for potential severe weather yesterday. It was the first “High Risk” outlook issued by SPC in 2014. According to The Encyclopedia of Arkansas History and Culture, the deadliest outbreak in Arkansas history occurred on March 21, 1952, when 112 people lost their lives. 
The most deadly recent outbreak was on March 1, 1997, which resulted in 25 Arkansas fatalities. Outside of Arkansas, a tornado hit Quapaw, OK on Sunday, killing one person and destroying the fire station. In Kansas, the governor declared a state of emergency for Baxter Springs, where a tornado destroyed 70 homes and 20 businesses. In all, SPC logged 31 preliminary tornado reports from five states on Sunday, 107 reports of damaging winds, and 118 reports of hail. Also on Sunday, an 11-month old died from injuries suffered during a tornado on Friday in Chowan County, North Carolina. It was the first U.S. tornado death of 2014. 

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