Fires, Floods, and Heavy Snow: an Extreme May Weather Situation
By
Dr. Jeff Masters
Published: May 3, 2013
A highly unusual jet stream pattern is bringing a bizarre combination of heavy May snows, flooding, extreme fire danger, and well below average severe thunderstorm activity to the U.S. A strong "blocking" high pressure system has set up over Greenland, blocking the normal west-to-east progression of weather systems. A truly unusual situation has developed where the blocking high has forced a low pressure system near Greenland to move southwestwards to a point just off the New England coast. The blocking high has also forced an unusually sharp southwards dip in the jet stream over the Central U.S., where all-time May snowfall and cold temperature records are being set. This loop in the jet stream will get cut off from the main flow of the jet over the weekend, forming a "cutoff" low that will drift over the Southeast U.S., bringing cold, flooding rains of 2 - 4" over a wide swath of the Southeast. But over the Western U.S., an unusually sharp ridge of high pressure has set up, bringing record high temperatures, a strong Santa Ana wind event, and dangerous fire weather. The Santa Ana wind event has entered its second day over Southern California, where a clockwise flow of air has brought offshore winds, record high temperatures in the 90s, powerful winds gusting from 40 - 75 mph, and relative humidities less than 5%. Three destructive fires have erupted since Wednesday. The largest of these fires is called the Springs fire, and has burned 10,000 acres near Camarillo, California, about 50 miles west-northwest of Los Angeles. According to Cal Fire, the blaze was 10% contained at 6:30 am PDT May 3. The hourly observations from Thursday, May 2 at Camarillo show the onset of the Santa Ana winds impressively. The temperature jumped from 54° to 81° between 7 am and 8am, and the wind went from calm to sustained 35 mph, gusting to 43 mph, by 9 am. The temperature Thursday afternoon topped out at 98°--a new record high for the date--and the humidity dropped to a desiccating 4%. The Santa Ana wind event will not be quite as strong Friday, but will still be powerful enough to keep firefighters from gaining the upper hand on the blaze. The situation will improve dramatically over the weekend, when a low pressure system will bring in air 10 - 15° cooler, onshore winds, and rain.
Figure 1. Residents look on as a back fire set by firefighters consumes the hillside behind their homes as a wildfire burns on May 2, 2013 in Newbury Park, Calif. (Photo by Kevork Djansezian/Getty Images)
Figure 2. A bad day to be on the Channel Islands. Offshore winds blow smoke from the Springs fire, burning about 50 miles west of Los Angeles on May 2, 2013, over the Channel Islands, where the smoke mixed with brighter marine stratocumulus clouds. Image credit: NASA.
A early start to the California wildfire season
According to the National Interagency Fire Center, as of April 26, the U.S. had the fewest fires and the lowest acreage burned by wildfires in 2013 for any year-to-date period over the past ten years. But in just the past two days, the acreage burned for 2013 has jumped by 20%. Severe drought conditions across much of the Western U.S. are likely to help fuel an early and severe wildfire season during 2013, they said in their latest monthly outlook, issued May 1. Fire season is expected to be in full swing during May--a full month earlier than usual--in Southern California, California's Sacramento Valley and adjacent lower foothills, and South Central Oregon. In California, “precipitation pretty much shut off at the beginning of the year,” NIFC wildfire analyst Jeremy Sullens said during a conference call with reporters. “Since they’re not expecting a lot more precipitation for the remainder of the summer, conditions are going to worsen as we go into the hotter part of the year.” Significant fire potential will increase to above normal during May in southeastern Arizona, much of western New Mexico, and northern Virginia. Late-season snows across the Rocky Mountains in Wyoming and Colorado have dumped enough moisture to delay wildfire season until its usual June start. However, these storms have largely missed southern Colorado, where the wildfire risks remain elevated.
Figure 3. Predicted May fire activity from the National Interagency Fire Center.
Water a precious commodity in California in 2013
As of May 2, California's Sierra Mountain snowpack was just 17% of average for the date, with a water content more typical of what is seen in early July. That's bad news for a state that relies on a steady stream of meltwater to keep reservoirs filled during the summer. The poor 2012 - 2013 snow season comes on the heels of a poor 2011 - 2012 snow season, as well. But thanks to good water years leading up to 2011 - 2012, two key reservoirs are above 80% capacity: Lake Oroville, the main reservoir for the State Water Project (86%), and Lake Shasta, the main reservoir for farmers in California's Central Valley (83%.) So, California will likely weather the dry conditions of the summer of 2013--but the snows of the winter of 2013 - 2014 had better be plentiful, or the state could be looking at a serious water shortage in 2014.
Figure 4. The water content of the snowpack in the Southern Sierra Mountains of California, from San Joaquin through Kern and Owens, was 9% of average for the date on May 2, 2013 (and 7% of the average for April 1.) The snowpack is usually not this thin until early July. Statewide, the snowpack was 17% of average for the date. Image credit: California Department of Water Resources.
Amazing May snowstorm smashes more records
A rare and historic May snowstorm continues to set all-time snow and cold records for the month of May. Winter Storm Achilles brought Arkansas its first May snowfall in recorded history this morning, and four other states have set unofficial new May snowfall records for a 2-day storm: 18" in Blooming Prairie Minnesota (previous record of 15"); 17" in Rice Lake, Wisconsin (previous record, 15.4"); 12" in Chariton, Iowa (previous record: 8"), and 6" in Warrensburg, MO (previous record: 4.5".)
Here are the latest peak snowfall totals by state as of 11am EDT May 3:
Buckhorn Mtn., CO: 28.2"
Near Warren AFB, WY: 22.3"
Blooming Prairie, MN: 18"
Rice Lake, WI: 17"
Bessemer, MI: 13"
Chariton, IA: 12"
Dalton, NE: 8.5"
Beresford, SD: 6"
Warrensburg, MO: 6"
Traer, KS: 5.3"
Maysville, AR: 3"
West Siloam Springs, OK: 1.5"
And here is a partial list of cities that have set all-time low temperature records for the month of May:
Shreveport, LA: 41° on May 3 (previous May record: 42°) Records for the city go back to 1874.
Abilene, TX: 33° on May 3 (tied with 33° on May 4, 1907.)
Denver, CO: 19° on May 2 (tied with 19° on May 3, 1872)
Fort Benton, MT: 14° on May 2 (tied with 14° on May 10, 1946)
Denton, MT: 9° on May 2 (previous May record: 13° set on May 1, 2005.) Denton's records began in 1948.
Wunderground's weather historian Christopher C. Burt plans to fully document the records from this week's epic storm in his post coming on Saturday.
Figure 5. The jet stream pattern for Winter Storm Achilles showed a very high-amplitude trough over the Midwest U.S., which allowed record-breaking cold air to flow southwards out of Canada.
Nor'easter for Northeast Florida
Adding to Mother Nature's unusually varied bag of tricks for the U.S. today is a very wet and windy Nor'easter centered just east of Melbourne, which is lashing the east coast of Florida with heavy rains and rough surf. The storm brought 8.29" of rain to St. Augustine, Florida in the 24 hours ending at 8 am EDT May 3, and a daily record deluge of 1.7" of rain to Orlando, 3.1" to Fort Lauderdale, and 4.14" to Key West on May 2. The storm also spawned an EF-0 tornado with 70 mph winds that touched down in Boca Raton on May 2, causing minor damage. Radar loops out of Melbourne, Florida show disorganized heavy rain bands with a bit of rotation just offshore, and satellite loops show disorganized heavy thunderstorms extend from Cape Canaveral to Georgia. Development into a subtropical depression is unlikely due to very high wind shear of 40 knots, but this system will hang around through Saturday, generating heavy rains of up to three inches along the northeast coast of Florida. Gale warnings and flood watches are posted along much of the East Central and Northeast coasts of Florida.
Jeff Masters
Increased Fire Danger for NYC
By
Kari Kiefer
Published: April 3, 2013
The National Weather Service issued Red Flag Warnings for parts of the Northeast on Wednesday, April 3rd valid through 8 pm EDT (some areas through 10 pm EDT). Dangerous fire conditions stretched from northern Maryland through Massachusetts, including New York City.
A Red Flag Warning means that critical fire weather conditions are expected or occurring. Any fires that start may spread rapidly and become difficult to extinguish.
The forecast of low humidity and gusty winds on Wednesday increased the risk of brush fires across the region. These conditions seemed to pan out, check out today's observations at Central Park, La Guardia Airport, and Philadelphia.
Dangerous fire conditions will persist for Thursday across the region as humidity will remain very low, generally under 25 percent. However, the winds will be much weaker with gusts under 20 mph. Nonetheless, outdoor burning is not recommended.
For more information about wildfire danger, burn restrictions and wildfire prevention and education please visit your state forestry or environmental protection website.
Record January Warmth in France and Australia while Record Cold in China and
By
Chris Burt
Published: January 7, 2013
Record January Warmth in France and Australia while Record Cold in China and India Persists
January has gotten off to an extreme start temperature-wise for many parts of the world although it has been fairly normal so far in the U.S.
European warmth
On January 5th the temperature peaked at 25.2°C (77.4°F) at Llau, France, the warmest January temperature on record for the country on the mainland and aside from the French Mediterranean Island of Corsica. The record for Corsica is 25.5°C (77.9°F) set at Solenzara on January 2, 1962. Switzerland also saw near record warmth for the month with a 23.7°C (74.7°F) temperature measured at Brissago. The January record for Switzerland remains 24.1°C (75.4°F) at Grono on January 19, 2007.
Australian Heat Wave
Temperatures remain in record territory for much of Australia following a blistering weekend. Wild fires in southeastern Tasmania burned to the ground at least 100 homes last Friday and Saturday and officials are still searching for almost 100 residents unaccounted for. The temperature peaked in the state capital of Hobart at 41.8°C (107.2°F) on Friday, the hottest temperature on record for the city (records began in 1882) and tied for the 2nd hottest temperature ever recorded in Tasmania (the record is 42.2°C (108°F) at Scamander on January 30, 2009). The Australian Bureau of Meteorology has issued a statement saying that today and/or tomorrow (January 7 or 8) will nationally average over 40°C (104°F) which, should it occur, approach or break the all-time record for the country. The hottest day (average national maximum temperature) on record is 40.17°C (104.3°F) on December 21, 1972.
An enormous wild fire burns near Ouse and Dunalley north of Hobart in Tasmania, Australia last Saturday. 100 people are still unaccounted for in the area. Photo by Kaycie Bradford/EPA.
India Cold
The northern Indian state of Uttar Pradesh, where New Delhi is located, continued to suffer from record cold temperatures that have so far claimed the lives of 175 people. Temperatures in New Delhi fell to a low of 1.9°C (35.4°F) on January 6th and the high temperature on January 2nd was just 9.8°C (49.6°F), the coldest daily maximum in 44 years. The coldest temperature at a low elevation site in the state so far has been -0.7°C (30.7°F) at Muzaffarnagar. Narnaul in Haryana State reported -3.0°C (26.7°F) an all-time record cold temperature for the site. In the Himalayan region of Ladakh temperatures fell to -16.4°C (2.5°F) at Kargil.
Dense fog enshrouds New Delhi as a week of unusual cold continues. Photo by S. Subramanium for The Hindu newspaper.
China Cold
China has been experiencing its coldest winter in 28 years so far according to media reports. Since late November the national average has been -3.8°C (25.2°F). The average temperature in normally frigid northeast China (Manchuria) has been even more anomalous at -15.3°C (4.5°F), the coldest for the period in 42 years. Temperatures below -40°C (-40°F) have been reported in Manchuria and far western Xinjiang province (these temperatures are far from record values for the region where the Chinese national absolute minimum temperature of -52.3°C/-62.1°F was measured at Mohe in Heilongjiang Province on February 13, 1962). The Chinese Meteorological Administration reports that 27,000 square kilometers (10,500 square miles) of sea surface has frozen in Bo Hai Bay, the greatest ice extent since records of such began in 2008.
Investigators inspect ships frozen to their docks in the port city of Jinzhou, Liaoning Province in China. Photo from REUTERS.
KUDOS: Maximiliano Herrera for European warmth statistics.
Christopher C. Burt
Weather Historian
The Exceptional U.S. Wildfire Season of 2012
By
Dr. Jeff Masters
Published: December 31, 2012
The 2012 U.S. fire season was the 3rd worst in U.S. history, with 9.2 million acres burned--an area larger than the state of Maryland. Since the National Interagency Fire Center began keeping records in 1960, only two years have seen more area burned--2006, when 9.9 million acres burned, and 2007, when 9.3 million acres burned. Although the 2012 fire season was close to a record for most acreage burned, the total number of fires--55,505--was the lowest on record, going back to 1960, said scientists at a December 2012 press briefing at the American Geophysical Union meeting in San Francisco. The average U.S. fire size in 2012 was the highest on record. A September 18, 2012 report, The Age of Western Wildfires, published by the non-profit research group Climate Central, found that the number of large and very large fires on Forest Service land is increasingly dramatically. Compared to the average year in the 1970s, during the past decade there were seven times as many fires larger than 10,000 acres each year, and nearly five times as many fires larger than 25,000 acres. On average, wildfires burn twice as much land area each year as they did 40 years ago, and the burn season is two and a half months longer than 40 years ago. The increase in large fires is correlated with rising temperatures and earlier snow melt due to climate change, but fire suppression policies which leave more timber to burn may also be a factor.
The Top 5 U.S. Wildfires of 2012
Whitewater-Baldy Complex Fire, New Mexico: Largest fire in New Mexico history
The Whitewater-Baldy Complex Fire started as two fires that merged, both caused by lightning. The Whitewater fire was first detected on May 16th, and the smaller Baldy fire was detected a few days earlier on May 9th. These fires then merged on May 24th and together burned a total of 297,845 acres until it was 100% contained on July 23th. Mid-July rain showers helped fire crew contain this fire. This fire was difficult to contain due to rugged terrain with gusty winds, and relative humidity less than 3%. The fire consumed timber, mixed conifer, poderosa pine, pinon/juniper, and grasses. The suppression costs of the Whitewater-Baldy Complex Fire surpassed $23 million, according to the GACC. This is the largest fire in New Mexico history, which surpassed the previous record of 150,000 acres consumed by the Las Conchas Fire in 2011.
Figure 1. Wunderphoto of Whitewater-Baldy Complex Fire submitted by AZMountaineer21.
Figure 2. Satellite image showing the complex nature of the Whitewater-Baldy fire with multiple hot spots in red outlines with multiple smoke plumes. Image courtesy of NASA's MODIS Aqua on June 7th, 2012.
Rush Fire, California: 2nd largest in California history
The Rush Fire started from lightning on Aug. 12th and burned through Aug. 30th, consuming 315,577 acres of northeastern California portions of western Nevada. The rapid and uncontrollable fire spread was due to extremely difficult terrain, gusty winds, and extremely dry grass, sagebrush, and junipers. Fire crews reported, "Live sage brush was as dry as dead sage brush." This fire was rated a major threat to federally protected wild horses, burros, and grouse by the BLM Eagle Lake Field Office. Once this fire reached into Nevada, where it burned over 43,000 acres, it threatened a major natural gas line as well as power transmission lines. This fire cost the U.S. approximately a total of $15 million. The portion of the fire in California reached 271,911 acres, and now constitutes the second largest California fire in modern history. The largest California fire remains the Cedar Fire in 2003, which consumed 273,246 acres.
Figure 3. Progression of the Rush Fire, August 12 - 20, 2012. Image courtesy of Inciweb.org, Rush Fire maps.
Waldo Canyon Fire, Colorado: most expensive in Colorado history
The Waldo Canyon Fire was the most expensive wildfire in Colorado history, costing $353 million, according to the Rocky Mountain Insurance Information Association. The cause of the fire is still under investigation, but investigators have determined that it was started within 3 miles of the Waldo Canyon trail head, off of U.S. 24, and was human-caused. The burn started on June 23rd and burned through July 10th, burning a total of 18,247 acres of brush, mountain shrub, oak, grass, pinion juniper, ponderosa pine, douglas fir, spruce, and limber pine. This fire was a major threat to neighborhoods and homes, as it started only four miles from Colorado Springs. Approximately 347 homes were burned and 2 people were killed by the Waldo Canyon Fire. Due to the proximity of this fire to nearby neighborhoods, over 32,000 residents were evacuated.
Figure 4. Image showing how close the Waldo Canyon fire was to homes in Colorado Springs. AP photo.
Figure 5. Flames from the Waldo Canyon Fire rolling down a hillside approaching a Colorado Springs neighborhood. AP photo.
High Park Fire, Colorado: 2nd largest in Colorado history
The High Park Fire was caused by lightning and first detected on June 9th in the mountains west of Fort Collins. The fire burned 87,284 acres of timber, grass, and brush until it was 100% contained on July 1st, making this the second largest fire in Colorado history. The largest Colorado fire remains the Hayman Fire, which burned 137,760 acres in 2002. The High Park Fire killed one person, and was briefly the most destructive fire in Colorado history, after destroying 259 homes. However, this record was quickly surpassed by the Waldo Canyon Fire just a few days later.
Figure 6. Plane throwing fire retardant onto the High Park Fire. AP photo.
Figure 7. The huge plume of the High Park Fire seen from a neighborhood. Wunderphoto submitted by turbguy.
Chips Fire, California: $55 million in suppression costs
California's Chips Fire began on July 29th and burned a total of 75,431 acres in northern California, including 48,297 acres of the Plumas National Forest, 18,374 acres of Lassen National Forest, and 8,762 acres of privately owned land. The cause of the fire is unknown. The fire forced hikers on the Pacific Crest Trail to bypass this section by hiking Hwy 70/89 or by taking a bus and skipping this section all together. The fire was contained Aug. 31st, with a total of $55 million in suppression costs. Mainly timber was consumed in this fire.
Figure 8. Satellite image of fires in northern California on August 11 2012, including the Chips fire. Image courtesy of NASA's MODIS Aqua on August 11, 2012.
Figure 9. Burn scar from the Chips Fire. Burned vegetation appears in red, unburned areas are in green. Image courtesy of NASA's Advanced Land Imager (ALI) on the Earth Observing-1 (EO-1) satellite on September 1, 2012.
Western U.S. wildfires expected to increase due to climate change
Expect a large increase in fires over much of the globe late this century due to climate change, says research published this June in the Journal Ecosphere. Using fire models driven by output from sixteen climate models used in the 2007 IPCC report, the researchers, led by Max Moritz of UC Berkeley, found that 38% of the planet should see increases in fire activity over the next 30 years. This figure increases to 62% by the end of the century. However, in many regions where precipitation is expected to increase--particularly in the tropics--there should be decreased fire activity. The scientists predicted that 8% of Earth will see decreases in fire probability over the next 30 years, and 20% will see decreases by the end of the century. The models do not agree on how fire danger will change for a large portion of the planet--54% for the period 2010 - 2039, and 18% for the period 2070 - 2099. Six key factors were found to control fire probabilities in the models. Most important was how much vegetation there was (NPP, Net Primary Productivity). Three other factors, about half as important, were precipitation of driest month, mean temperature of warmest month, and the difference between summer and winter temperature. Two other minor factors were mean temperature of wettest month, and annual precipitation. The authors found that future fire occurrence appears to primarily be a function of available moisture in many areas, and that the expected global increase in temperature of 3.5°C used in the models will not become the single dominant control on global wildfire. In the U.S., the regions most at risk of increased fires are the tundra regions of northern Alaska, and the West, with Arizona and Colorado at particularly high risk.
Related: Wildfires in the U.S. will be at least twice as destructive by 2050, burning around 20 million acres nationwide each year, according to a federal report released by the U.S. Department of Agriculture in 2012.
Figure 10. Predicted fractional change in fire probability for the period 2010 - 2039 (top) and 2070 - 2099 (bottom) for the average of sixteen climate models used for the 2007 IPCC report. For the 2010 - 2039 period, the models agree that 8% of Earth will see decreases in fire probability, 38% will see increases, and the models are too uncertain to tell for the other 54%. For the 2070 - 2099 period, the models agree that 20% of Earth will see decreases in fire probability, 62% will see increases, and the models are too uncertain to tell for the other 18%. Image credit: Climate change and disruptions to global fire activity, Moritz et al., 2012, from the journal Ecosphere.
Coolest fire video of 2012: A fire tornado in Curtin Springs, Australia, from mid-September, 2012. NOAA comments: "While rare, fire tornadoes (also known as fire whirls) generally form when superheated air near the surface of a large fire zone rises rapidly in an airmass where sufficient horizontal or vertical vorticity (spin in the atmosphere) is also present. Much like a dust devil or whirlwind, the rapidly rising air above a wildfire can accelerate and turn the local vorticity into a tight vertical vortex, now composed of fire instead of dust."
Kari Kiefer and Jeff Masters
Wunderground's New Fire Page
By
Kari Kiefer
Published: September 28, 2012
We have launched our new Fire Page. You can find it at http://www.wunderground.com/fire. Or go to the Severe tab from the home page and select Fire Weather. The page features a map with various fire layers and tools for predicting fire spread.
The newest map layer is Fire(inciweb), which incorporates data from The Incident Information System (Inciweb). Inciweb is an inter-agency information management system created to provide the public of incident related information. In other words, its a one-stop shop for fire information for the US. By clicking on the fire hat icon in the center of the fire perimeter, the fire information loads below the map. This table loads detailed information on the fire, such as overview, cause, date of origin, current size. percent contained, estimated date of containment. Some fires will have additional details like fuels burned, fire behavior, significant events (which includes road closures and evacuations), planned actions, and sometimes more.
As of September 28th, 2012, the Mustang Complex Fire in Idaho the largest wildfire in the US, at 338,787 acres. You can view the inciweb fire information by turning on the Fire(inciweb) layer and zooming into Idaho.
If you want to do some fire spread forecasting of your own, you can turn on the weather stations layer and see what the winds are doing. If the winds are predominantly from the north, you can assume the fire will propagate to the south, as well as the smoke plume. However, the fuels (or vegetation type) play a big role in which direction the fire will spread. You can turn on the Fire(risk) layer to determine the Fire Danger Rating nearby the fire. The fire has a higher chance of spreading in areas of high fire danger because the model takes into account the current and previous weather conditions, vegetation types and fuel moisture content. This is a nice general fire danger scale. There are additional options on this layer to display such as the Haines Index (which takes into account atmospheric stability), the Keetch-Byram Drought Index (which involves soil and ground moisture), and the 10-hour, 100-hour, and 1,000-hour Dead Fuel Moistures. These are a bit tricky to understand. Consider small vegetation of 0.25 to 1.0 inch in diameter. These are the smallest needles and shrubs, and since they are so thin, they are able to dry out the quickest and called the 10 hour Dead Fuel Moisture Content. The thicker branches and logs that are 3 to 8 inches in diameter take the longest to dry out, and are called 1,000 hour Dead Fuel Moisture Content.
For the Mustang Complex Fire, the wind is currently taking the smoke plume northward, but the fire danger to the north of the fire is green, or low. This implies that the danger isn't high. However, I would still be worried if I were north of the fire because the 1,000 hour Dead Fuel Moisture is dry around the fire, and fire spread is likely. Complex terrain also allows for rapid fire spread for two reasons: 1) It is difficult to get fire personnel to the fire to manage and contain it and 2) When fires are in canyons and valleys, the vegetation ignites more readily on the adjacent side because it has been preheated by the flames.
Check the fire page often to keep updated on wildfires across the nation!
Kari
