Flooding Woes Trending in the Wrong Direction

Back in April we outlined how Flooding is the by far the most common natural disaster and therefore the worst in terms of costliness, death, and destruction. Flooding woes come in many ways too, including long-term swelling lakes and rivers, storm surge and coastal flooding from Hurricanes and Tropical storms, and flash floods from downpours from severe thunderstorms. Last year’s Hurricane Harvey alone caused over 125 billion dollars, mostly from the widespread flooding across East Texas and Louisiana.

More Flooding Woes from Hurricane Florence

Yet another example of the ongoing cost of flooding was this month’s Hurricane Florence over the Carolinas. Five major watersheds saw an average of 17.5 inches of rain over four days, calculated to be the second worst in the last 70 years (second only to Hurricane Harvey’s 25.6 inches). The storm caused widespread flooding across a 14,000 sq mile area across both states. With two of the worst storms in consecutive years, leading meteorologists are blaming warmer oceans, more moisture and slower moving storms due in various ways to climate change causing tropical cyclones to dump more rain.

florence landfall lead to flooding woes

NOAA’s view of Hurricane Florence making Landfall near Wilmington, NC on September 14th

12 counties in North Carolina, where the storm made landfall near Wilmington, remain under varying types of evacuation orders as flood waters are either still cresting or very slowly receding. Consequently, nearly 300 roads are still closed across NC and neighborhoods in cities that thought they made it through the event unscathed are now being impacted. The toll on residents and infrastructure is estimated in the ballpark of 38 billion (and rising), making it the sixth costliest tropical cyclone on record.

Insurance Should Help, No?

Just as after last year’s Harvey impact (125 billion), flood insurance again has been a hot topic. With estimates of a million people dealign with flooding woes across the two states, it’s no surprise that in the aftermath of Florence there’s been a heap of national news coverage on the issue. If you google “Florence Flood Insurance” every article highlights the dire situation and elaborates on the fact that typical homeowner’s insurance doesn’t cover most of the people (estimated at 85%) affected. The other 15% have opted in to their insurance plan’s specialized flood coverage or were informed enough to join the National Flood Insurance Program (NFIP). Whether the others are uninformed, can’t pay, or don’t want to pay extra they are now (similar to Houston residents after Harvey) in what these articles are calling a ‘miserable’ fallout situation.

Rescued from flooding woes

Members of the 106th Rescue Squadron, 106th Rescue Wing, New York Air National Guard, drop from an HC-130J Combat King II aircraft during a rescue mission during Hurricane Florence, Sept. 17, 2018.(U.S. Air Force photo by Senior Airman Kyle Hagan)

Florence, like Harvey, turned out to be less of a wind event and with flood excluded on most homeowner’s policies, experts from the insurer point of view are expecting to deal with a “manageable” and “insignificant” event. Of the $38 billion dollar bill, only an estimated $1.7 billion to $4.6 billion will fall on the insurance industry from Florence’s winds and storm surge (damage from which are covered).


Question: Who will pay for homeowners who want to rebuild their homes then?

Answer 1: The Homeowner

  •  Uninsured homeowners will have to pay out of pocket or get loans from the Federal Government to pay for repairs to their flood-damaged homes. The loans have to be repaid in full.

Answer 2: The Taxpayers (indirectly)

  • The NFIP is vastly under-funded by policyholder revenue and multiple loans and bailouts since Hurricane Katrina have the taxpayers regularly on the hook for billions of dollars in relief.

This New York Times article sums this up nicely.

Flooding affects the US populace, both coastal and inland, every year. Implications from flooding events are statistically worsening whether from continued warming oceans and climate change or something else causing these outlier events to be more regular. Flooding woes like this month’s Florence is life changing for a huge number of people and communities, and unfortunately, it seems it’s but a matter of time until the next one with the same storyline.


Sources

CBS News
NY Times
Insurance Journal
Think Realty
National Flood Insurance Program (NFIP)
FEMA

Hurricane Florence Starts its Assault on North Carolina

Hurricane Florence Current Situation

As of: 2100 UTC, Sep 13nd, 2018

  • Location: 100 miles ESE of Wilmington, NC
  • Size: Category 2
  • Maximum Sustained Winds: 100 mph
  • Present Movement: WNW at 5 mph
  • Minimum Central Pressure: 955 mb
  • Impact: Up to 11 feet of storm surge, heavy rain causing flash flooding
  • Incident Page: NHC Public Advisory
  • News Article: WunderBlog

Hurricane Florence Outlook

Hurricane Florence has started to impact North Carolina’s barrier islands. As it reaches landfall, the storm has been downgraded to a Category 2 Hurricane, but don’t let the category number fool you. Florence remains a massive and devastating hurricane. The storm continues to grow in area and is predicted to impact a large portion of the North and South Carolina coasts. Maximum sustained winds are hovering around 100 mph, with some higher gusts. Hurricane force winds extend up to 80 miles from the eye of the storm. Some coastal areas are already seeing storm surge flooding.  At the peak of the event, areas around river outflows could be dealing with storm surges up to 11 feet. The greatest storm surge inundation is expected between Cape Fear and Cape Hatteras where river outflow will meet the storm surge inundation.  Inland areas are not necessarily in the clear from the damage. Significant flash flooding and prolonged river flooding could extend as far as the Appalachians through early next week as the storm moves inland.

Nearly 2 million people are under hurricane Warning. Authorities are cautioning residents in evacuation zones to get out because first responders will not be able to perform rescues during the storm. Power outages are already affecting around 100,000 people and are expected to get worse as this incident continues.

Click here to look back on this year’s hurricane season outlook to see how the predictions are panning out.

View of the storm path and cone of uncertainty.

 

Predicted Flash Flooding Risk

Hurricane Irma – One Year Later

  • Timeline: Aug 30 – Sept 13, 2017
  • Severely Impacted Areas: USVI, Puerto Rico, Georgia, Florida
  • Maximum Sustained Winds: 180 mph
  • Fatalities: 52 direct (wind-driven debris, storm surge), 82 indirect (heart attack, house fires, vehicle accidents)
  • Damages: $64.76 Billion (5th costliest tropical cyclone on record)

Hurricane Irma’s Trek Across the Atlantic

This week marks the anniversary of Hurricane Irma forming and making landfall across the Southern United States. Tropical Storm Irma became a named storm on the 30th of August, 2017. It moved steadily across the Atlantic Ocean at 10-15 mph. A week later, now a Category 5 Hurricane, Irma passed by Puerto Rico narrowly missing it to the north. The storm continued skirting along the northern coasts of the Caribbean Islands including the Dominican Republic and then Cuba. Then, a glancing landfall moment happened along the North Cuban coastline, briefly weakening Irma to a Category 3 Hurricane as it turned north toward Florida.

Throughout Irma’s approach to the US Mainland, forecasts remained uncertain and models were not in agreement. Every update led to questions: would Miami or Orlando would be directly in the path, would the storm would move farther west and trail the Gulf Coast side of Florida, or would it shift a bit more west and come up the Gulf and end up hitting the Florida panhandle? One thing was certain – wherever landfall occurred, winds, rain, and storm surge were going to be affect a lot of people and infrastructure. Hurricane Irma ended up making landfall as a Category 3 Hurricane on September 10th, 2017, just south of Fort Myers along the SW part of Florida’s peninsula.

Hurricane Irma's path across the Atlantic Ocean (Source: WikiCommons)

Hurricane Irma’s path across the Atlantic Ocean (Source: WikiCommons)

Rebuilding Ongoing

While power has been restored and roadways cleared, many areas still see the impacts of these storms. The Florida Keys and much of Florida’s peninsula experienced hurricane force winds, nearly a foot of rain, and around 10ft of storm surge. Cleaning up the wide-spread damage is a daunting undertaking; however, FEMA, charities from around the world, and community efforts came together to assist residents to get their areas back to habitable conditions. By October 1st, much of Key West’s historical district was back in operation and welcoming guests. Nearer the main land, the damage was more extensive. Some businesses and homeowners have chosen not to rebuild and now those that had less significant repairs have vacant lots as neighbors. Each family has to make the best decision for their circumstances and many chose to shift to a new location rather than go through the extensive rebuilding process.

Damaged structures on Ramrod Key, FL after Hurricane Irma passed through the area. (Source: Joe Raedle)

Damaged structures on Ramrod Key, FL after Hurricane Irma passed through the area. (Source: Joe Raedle)

When coming home after a storm, reentering the region, property, and structure safely is important. Ensuring flooding conditions haven’t led to moldy conditions, debris is properly removed, and the structure remains sound are just a few common checks. FEMA and the Insurance Institute for Business & Home Safety shared Safety Guidelines useful to making this process as smooth as possible.

 

Sources

National Hurricane Center, The Weather Channel, FEMA

RedZone Disaster Intelligence

How Can Technology Assist Insurance Carriers With Disaster Moratoriums?

Have you ever wondered how home insurance companies deal with writing new policies in an ongoing disaster zone? Well the truthful answer is they don’t. For instance, when a large wildland fire is threatening homes or has the potential to, insurance carriers place a moratorium on the surrounding landscape. A moratorium is a temporary, but indefinite hold on writing any new home insurance policies within the blanket area that is declared. The purpose of this practice is to stop new customers who aren’t covered for fire, or other disaster related damages, from buying a policy right before the home is damaged. The problem is the geographic regions that are typically chosen for a moratorium are too large. The regions that are chosen usually include areas that are not threatened by the disaster in any way shape or form. This leaves an undesirable gap in business for both the insurers and possible policy holders. Here at RedZone we like to focus on utilizing technology coupled with expertise to solve complicated problems such as this one.

Wildfire

                With advances in current wildfire modeling, insurance companies can have a more precise understanding of what is taking place on the ground currently, as well as what is likely to take place in the upcoming hours of the fire. Wildfire modeling accounts for the essential driving factors behind a wildfire so it can accurately depict where the fire is heading. You can read more about the aspects taken into account in RedZone’s Wildfire model here. By using a wildfire model, insurance companies can reduce the size of the geographic areas that are placed under a moratorium. Then the carriers will have an understanding of where the fire will be moving. This benefits both parties involved in many ways. If a home is not covered for wildfire, and a fire breaks out near the home it may spark an interest for the homeowner to obtain coverage on their home for fire. If the area that the home is located in is under a moratorium, the homeowner will not be able to purchase a policy for that type of coverage.

Canyon 2 Wildfire Model – first 24 hours without suppression

canyon2 final perimeter

Canyon 2 Fire Perimeter – shows the fire’s extent in the first 48 hours with suppression

Hurricane

                In the case of hurricanes, insurance carriers are even more precautious about writing new business when a storm of hurricane magnitude is approaching. The process of putting a moratorium in place for a storm begins when the National Weather Service declares a low pressure system to be of a tropical storm magnitude. You can learn more about hurricane formation and power at RedZone’s Blog on Hurricanes Harvey and Irma. Insurance companies immediately put a moratorium into effect for the projected zones that will be impacted by the incoming storm. These areas range from zip codes to counties and even expanding to encompass entire states that could possibly be impacted by the storm. A large portion of homes that are located in a moratorium of that size will likely not be affected by flooding or wind damage from the storm.

One of the ways that GIS (Geographic Information Systems) can help with this problem is with a Digital Elevation Model (DEM) Dataset. When loaded into a GIS this data will depict what the terrain on the ground will look like. These elevation layers coupled with flood plain data would give an accurate depiction of the level of threat to a structure. What has to be taken into account is that each storm is different. The flood data chosen must accurately match the expected rainfall from the storm in the general location. One solution is to utilize the most severe flood data available, so that the estimations are on the safer side. Another factor that needs to be considered is the damage that occurs from wind during one of these events. GIS is capable of running buffers based on the projected storm path. A buffer coinciding with the relative wind speeds that are capable of damaging homes would be a safe way of creating more accurate moratorium zones during a hurricane. 

NOAA track Oct8

NOAA Potential Track Map issued Thursday Oct 10th, 8pm eastern

Source(s):

http://wiseinsurancegroup.com/insurance-moratoriums-binding-prohibitions/

https://www.insurancejournal.com/news/west/2017/12/18/474612.htm

https://www.jebrown.net/content/169/brush-fire-moratorium

http://velocityrisk.com/commercial-insurance/moratorium-policy

https://www.propertycasualty360.com/2016/10/06/how-the-insurance-industry-prepares-for-hurricanes/?slreturn=20180326132445

DISASTER 101 – FLOODING

When most people think of natural disasters, the first thing to come to mind is not likely flooding. However, flooding is the most common natural disaster. Flooding occurs in all 50 states, accounts for 40% of natural disasters, averages 5 billion dollars in damage each year, and claimed an average of 75 lives per year over the last 30 years.

Worldwide, statistics are similar.

According to the 30 year average, flooding is responsible for the most weather-related fatalities.

TYPES OF FLOODING

River and Lake Flooding

River and lake flooding is probably what most people envision when they think of floods. Heavy rainfall or snowmelt can cause water levels to rise overflowing banks and levees. River flooding is common in the Midwest as rain and snowmelt swells the tributaries that feed into larger rivers downstream. Once the water level crests the river banks, the area that is inundated can be widespread. Low lying areas, saturated soils, and urban areas can further exacerbate the effects of the overflow and take days to dissipate.

California experienced flooding in February when a weekend of storms increased runoff from Anderson Lake and flooded low-lying areas of San Jose. The early year storms also prompted the evacuation of over 88,000 people near the weakened Oroville Dam.

In May of 2017, heavy rainfall over the Midwest caused widespread flooding. Nearly 15 inches of rain fell over multiple states, saturating soils, and swelling multiple rivers above historic levels. Numerous levees were breached which flooded towns causing an estimated $1.7 billion dollars in damages to homes, businesses, and infrastructure.

40% of all natural disasters are flooding.

Coast Guard overflight of South Carolina flooding

Coastal Flooding and Storm Surge

A form of flooding happens regularly along coastlines due to the cycle of rising and lowering tides. Tides are a regular rise and fall of sea level caused by the gravitational interplay of the sun, moon, and earth. Occasionally, these tides can be exceptionally high. An increase of just a few feet is more than enough for tides to breech natural and man-made barriers. Many coastal cities are very near, or in some cases lower than, sea level making them especially prone to any change in sea level.

Storm surge can also cause extreme coastal flooding. The surge develops during severe weather, hurricanes, and tropical storms raising sea level as much as 25 feet. Sea level rise is the result of the low atmospheric pressure found in these storms which has a similar effect on sea level rise as the gravitational pull on tides. High winds common with these storms also cause large waves to batter the coast and push water farther inland. In worst case scenarios, the storm surge strikes the coast during a high tide cycle, increasing the flooding exponentially. Storm surge flooding is responsible for 90% of hurricane related deaths and the majority of the damage to structures.

In August of 2017, Hurricane Harvey alone caused over $125 billion dollars in damage and killed 89 people. The majority of the devastation caused by Harvey was a direct result of the widespread flooding of the Houston area.

Flash Floods

Flash floods can result from a variety of causes, but the common denominator is that they develop quickly and are normally caused by heavy rainfall. These floods can also be the result of snow melt, dislodged ice, inadequate urban drainage, or dam breaks. The actual volume of water carried in a flash flood is usually less than other flood types but the water is channeled down confined spaces which causes it to move with devastating force and speed. Because of this speed, flash floods are very dangerous, easily carrying mud, rocks, and trees in its flow. A Weather Channel article stated that, “water flowing at 7 mph has the equivalent force per unit area as air blowing at EF-5 tornado wind speed.” Whereas, “water moving at 25 mph has the pressure equivalent of wind blowing at 790 mph, faster than the speed of sound.”

 

BASIC SAFETY AND PREPAREDNESS

Ready.gov provides many helpful tips.

Be Mindful

  • Stay tuned to phone alerts, TV, or radio for weather updates, emergency instructions, or evacuation orders.
  • Avoid walking or driving through flood waters. 6 inches of moving water can knock a person over, and one foot of moving water can sweep a vehicle away. According to the Environmental Protection Agency, the leading cause of flood-related injury and death is individuals attempting to drive through flood waters.
  • Do not drive over bridges that are over fast-moving floodwaters. Floodwaters can scour foundation material from around the footings and make the bridge unstable.
  • If there is a chance of flash flooding, move immediately to higher ground.

Protect your home

  • Know your flood risk, avoid building in flood plains, and consider buying flood insurance.
  • If you have to evacuate due to flooding, and if safety permits, turn off all the utilities to your home and attempt to move valuables to the highest possible level.

SOURCES

https://www.ready.gov/floods
https://www.nssl.noaa.gov/education/svrwx101/floods/types/
https://www.ncdc.noaa.gov/billions/events/US/2017-2018
http://www.floodsite.net/juniorfloodsite/html/en/student/thingstoknow/hydrology/floodtypes.html
https://weatherology.com/articles/106/The+Dangers+of+Flash+Floods.html
https://weather.com/storms/severe/news/power-flood-water-20130704
https://www.livescience.com/23913-flood-facts.html

Blizzard, snow

Nor’easters Repeatedly Hammer the East Coast with Blizzard Conditions

Update: 03/29/2018 all four Nor’Easter storms have passed.

As the forecasts indicated when this blog was initially written, a 4th Nor’easter storm hit the east coast. Winter storm Toby began to run its course on the landscape in the early morning hours of Wednesday March 21st. After Toby had passed the snow accumulation was shocking in the areas that were hit hardest. Areas of Pennsylvania received over a foot of snow in the short period of time that Toby was over the area. Central Park in New York City recorded 8 inches of snow while some areas in Long Island, New York reported up to 20 inches from the weather system. Unlike the previous three Nor’easter storms that occurred in the weeks leading up to Toby, this storm actually impacted the entirety of the east coast in varying levels. Upon the arrival of Toby, parts of Florida and Georgia both received heavy hail in some areas along with drastically increased wind speeds along the coast. This storm actually triggered tornado watches in the northern portions of Florida. Have storms of this magnitude hit the east coast in such a short period of time before?

Even though having four powerful Nor’easters hit the east coast in such a rapid succession is uncommon, it has happened before. Actually, as recently as 2015 three Nor’easters struck the same area distributing similar weather patterns that were seen with the four storms that have hit this month. In 2015 the series of Nor’easters started with Winter Storm Lola (January 23-24 2015), and then came Winter Storm Juno (Jan. 26-28, 2015), Finally Winter Storm Linus (Feb. 2, 2015) made its arrival in the area. These storms broke records in the City of Boston, Massachusetts for the most accumulation of snow during winter that has been recorded to date.

Original Post

The word Nor’easter has been quite prevalent in the media for the last two and a half weeks as a description for the type of storms that have been wreaking havoc across the east coast. Nor’easter storms get their name from the predominant wind direction that the system gets pushed in from. These storms are pushed from the Atlantic Ocean into the East Coast of the U.S., carrying massive amounts of water with them. A typical Nor’easter storm would consist of gale force winds (around 40 miles per hour and up), rough seas off the east coast, and massive amounts of precipitation in the form of rain or snow. The way these storms form and become so powerful is quite fascinating. The polar jet stream transports cold arctic air down over the United States and meets with the warm air of the jet stream located over the gulf coast. This collision of colder air over land and warmer moist air over the Atlantic Ocean is the driving force that creates these cyclonic storm systems. Nor’easters have been seen throughout all seasons of the year, but they are the most common and the most powerful between the months of September and April.

Satellite, Imagery

This Satellite imagery displays what the formation of a Nor’easter storm looks like from space.

Current Status of the East Coast

            Yesterday, the third Nor’easter storm made landfall on the northern reaches of the east coast. The series of storms started on March second when winter storm Riley brought widespread precipitation in the forms of heavy rain and snow that earned the declaration for blizzard condition warnings in many counties. The storm hit the coast of New England with a force that would cause massive destruction. Storm surges brought about large scale coastal erosion, along with flooding of many coastal areas. At the peak of the first storm, over 1 million residents of New York, New England, and North Carolina were without power for an extended period of time. Riley was followed shortly after by winter storm Quinn. Quinn had a similar impact to the east coast, which was still trying to recover from the first storm. During this second large storm, thousands of flights had to be cancelled due to unsafe flying conditions for large passenger carrying aircraft. This storm system again passed through, leaving an absurd amount of snowfall, high wind speeds, and unsafe travel conditions. Finally, winter storm Skylar made its way to the east coast during the evening hours on Tuesday. Similar to the previous two storms that have occurred in the last two weeks, this powerful weather system left in its wake an abundance of rain and snow, accompanied by gale force winds and loss of power for hundreds of thousands of residents in the area. The storm surges seen during these storms are similar to what occurred during some of the hurricanes that hit the southern coast of the U.S. this year. You can read about the damages that occurred during these incidents in RedZone’s previous blog “Hurricanes Harvey and Irma batter Southern US”.

GIS, Snow forecast

This map provided from FEMA shows the snow levels that are expected from winter storm Skylar.

Forecast for the East Coast

Unfortunately, forecasts for the east coast are looking like residents “aren’t out of the woods yet” when it comes to heavy winter storms. The discrepancies between the American and European forecast models are mainly surrounding the formation of this storm system once both air masses collide on the east coast. What is known is that another wave of cold air is making its way across the lower 48 states through this weekend. The cool air will arrive on the east coast late Monday night into Tuesday of next week. Due to the amount of time it will take for this system to make its way over to the east coast, meteorologists cannot say with certainty how powerful this storm will be. As the week progresses, the models will become more accurate, providing more details on the occurrence of this possible Nor’easter formation.

 

Sources: https://www.weather.gov/safety/winter-noreaster

https://weather.com/storms/winter/news/2018-03-01-winter-storm-riley-noreaster-high-winds-coastal-flooding-heavy-snow

https://weather.com/storms/winter/news/2018-03-14-snow-ice-west-midwest-east-mid-march

https://content.govdelivery.com/attachments/USDHSFEMA/2018/03/13/file_attachments/972703/FEMA%2BDaily%2BOps%2BBriefing%2B03-13-2018.pdf

https://weather.com/storms/winter/news/2018-03-19-winter-storm-toby-fourth-march-noreaster-northeast-snow

https://weather.com/storms/winter/news/2018-03-20-four-noreasters-three-weeks-winter-storm-quinn-riley-skylar-toby

road closure thumbnail

Incoming Heavy Rains Increase Debris Flow Risk Yet Again

The National Weather Service (NWS), Los Angeles Office is warning the region that sustained heavy rains are incoming for the majority of the rest of the week. The beginning of the rain is set to arrive today (Tuesday) and last well into Thursday. The “atmospheric river” storm is expected to bring between 5 and 10 inches of rain in the foothills and mountains, significantly more total rainfall than the 1/9 debris flow, which brought between 3 and 6 inches to the region. The NWS says this storm is projected to have the heaviest rainfall and the longest duration of this winter storm season. “All models indicate high confidence in rainfall totals and the duration of the storm.”

Rainfall forecast through 3/26

National Weather Service Precipitation forecast for the Greater Los Angeles and Santa Barbara Areas through the weekend. Recent Fires are seen in black on the map as worry grows about debris flow potential.

Debris Flow Risk for Santa Barbara County Burn Areas

We caught Monday’s press conference from Emergency Officials with Santa Barbara County, who are stressing the seriousness of the renewed threat flooding and especially of debris flow.  Opening the discussion, Meteorologist, Mark Jackson warned, “A key worry with this storm is rainfall rates that can trigger debris flows. It’s not necessarily the total amount of rain that occurs; it’s how fast that rain falls.” Well, the latest meteorological models by the National Weather Service indicate that there is potential for rainfall intensity of between .5 to .75 inches per hour, which is enough to trigger debris flows at any time during the storm.

Recent Burn Areas tweet

NWS Los Angeles warning via tweet today that debris flows near recent fires are likely across the region

As a result, many residents downslope of Thomas and other fires in the region (seen as black in the map above & highlighted in the tweet below) have been evacuated or at least cautioned. Santa Barbara County is also managing and updating an evacuation map found here.  In addition, Rob Lewin, director of the Santa Barbara County Office of Emergency Management, warned the amount of rain and the intensity is enough to cause flooding even without the impact of the recent fires. “We could experience localized flooding and road closures which are not isolated to the burn areas. The threat of rock falls, mud slides and debris flow is high,” he noted.

“A key worry with this storm is rainfall rates that can trigger debris flows. It’s not necessarily the total amount of rain that occurs; it’s how fast that rain falls.” – Mark Jackson, NWS Meteorologist

Storm Facts:

  • Heaviest Rainfall for Ventura County to San Luis Obispo County is expected Wednesday afternoon to Thursday morning (March 21 – March 22)
  • Heaviest Rainfall for LA County is expected Thursday into Thursday Night (March 22)
  • Rainfall totals for the Coasts/Valleys will be 2-5 inches, for the Foothills/Mountains more like 5-10 inches.
  • Flash flooding and significant debris flows near recent burn scars are likely
  • Urban and small stream flooding expected
  • Slight chance of main stem river flooding
  • Road closures anticipated due to rock fall in the mountains
  • Residents in the Extreme and High Risks areas of Santa Barbara County are required to evacuate at noon on Tuesday (March 20)
  • Mandatory evacuations prompted for areas below the Thomas, Whittier, and Sherpa Fires

Sources:

National Weather Service

Santa Barbara County Emergency Services

KSBY News

Blizzard, snow

Nor’easters Repeatedly Hammer the East Coast with Blizzard Conditions

The word Nor’easter has been quite prevalent in the media for the last two and a half weeks as a description for the type of storms that have been wreaking havoc across the east coast. Nor’easter storms get their name from the predominant wind direction that the system gets pushed in from. These storms are pushed from the Atlantic Ocean into the East Coast of the U.S., carrying massive amounts of water with them. A typical Nor’easter storm would consist of gale force winds (around 40 miles per hour and up), rough seas off the east coast, and massive amounts of precipitation in the form of rain or snow. The way these storms form and become so powerful is quite fascinating. The polar jet stream transports cold arctic air down over the United States and meets with the warm air of the jet stream located over the gulf coast. This collision of colder air over land and warmer moist air over the Atlantic Ocean is the driving force that creates these cyclonic storm systems. Nor’easters have been seen throughout all seasons of the year, but they are the most common and the most powerful between the months of September and April.

Satellite, Imagery

This Satellite imagery displays what the formation of a Nor’easter storm looks like from space.

Current Status of the East Coast

            Yesterday, the third Nor’easter storm made landfall on the northern reaches of the east coast. The series of storms started on March second when winter storm Riley brought widespread precipitation in the forms of heavy rain and snow that earned the declaration for blizzard condition warnings in many counties. The storm hit the coast of New England with a force that would cause massive destruction. Storm surges brought about large scale coastal erosion, along with flooding of many coastal areas. At the peak of the first storm, over 1 million residents of New York, New England, and North Carolina were without power for an extended period of time. Riley was followed shortly after by winter storm Quinn. Quinn had a similar impact to the east coast, which was still trying to recover from the first storm. During this second large storm, thousands of flights had to be cancelled due to unsafe flying conditions for large passenger carrying aircraft. This storm system again passed through, leaving an absurd amount of snowfall, high wind speeds, and unsafe travel conditions. Finally, winter storm Skylar made its way to the east coast during the evening hours on Tuesday. Similar to the previous two storms that have occurred in the last two weeks, this powerful weather system left in its wake an abundance of rain and snow, accompanied by gale force winds and loss of power for hundreds of thousands of residents in the area. The storm surges seen during these storms are similar to what occurred during some of the hurricanes that hit the southern coast of the U.S. this year. You can read about the damages that occurred during these incidents in RedZone’s previous blog “Hurricanes Harvey and Irma batter Southern US”.

GIS, Snow forecast

This map provided from FEMA shows the snow levels that are expected from winter storm Skylar.

Forecast for the East Coast

Unfortunately, forecasts for the east coast are looking like residents “aren’t out of the woods yet” when it comes to heavy winter storms. The discrepancies between the American and European forecast models are mainly surrounding the formation of this storm system once both air masses collide on the east coast. What is known is that another wave of cold air is making its way across the lower 48 states through this weekend. The cool air will arrive on the east coast late Monday night into Tuesday of next week. Due to the amount of time it will take for this system to make its way over to the east coast, meteorologists cannot say with certainty how powerful this storm will be. As the week progresses, the models will become more accurate, providing more details on the occurrence of this possible Nor’easter formation.

 

Sources: https://www.weather.gov/safety/winter-noreaster

https://weather.com/storms/winter/news/2018-03-01-winter-storm-riley-noreaster-high-winds-coastal-flooding-heavy-snow

https://weather.com/storms/winter/news/2018-03-14-snow-ice-west-midwest-east-mid-march

https://content.govdelivery.com/attachments/USDHSFEMA/2018/03/13/file_attachments/972703/FEMA%2BDaily%2BOps%2BBriefing%2B03-13-2018.pdf

Burn Scar

Debris Flow Devastates Montecito, CA Immediately After The Thomas Fire

While the threat of the Thomas fire just recently diminished in Ventura and Santa Barbra Counties, residents were weary to hear that they are now being threatened by mudslides originating from within the burn area. Rain started Monday afternoon in the areas of Santa Barbara and Ventura Counties, with the peak rainfall being around 2:30 AM Tuesday morning. The rain came down in amounts up to an inch per hour over the burned area, which the incident commander reported as being a critical factor in the amount of sediment and debris being carried by this amount of water. The devastating debris flow ranged from Cold Springs Canyon to Toro Canyon, and wreaked havoc all the way down to Highway 101. The debris flow was so strong in some locations that it pushed homes off of their foundations and carried them several hundred feet.

First responders have been preparing for this incident since Monday morning by preemptively staging resources in the areas that were forecasted to be impacted the most severely. This strategic placement of resources was followed by officials releasing evacuation zones. The warning stated that all residents within mandatory evacuation zones should leave by 12 noon on Monday in preparation for the heavy rains that were forecasted for the area. Since the early morning hours of Tuesday, first responders have been in a search and rescue mode: still actively engaged in performing helicopter and contact rescues. The threat from this debris flow still remains and first responders are warning residents to stay away from the area if at all possible.

Debris flow

An explanation of a debris flow, and its power.

 

Over the last couple weeks of the Thomas Fire the Federal Burned Area Emergency Response (BAER) Team has been evaluating the blaze’s impact to the fire area and watersheds by predicting debris flow hazards should rains like this impact the area. The orange, red, and dark red areas were determined to have the highest probability of debris flow during a heavy rain event. The BAER team is currently embedded with the Santa Barbara and Ventura Office of Emergency Services to assist them in implementing response plans for communities downstream of the fire.

BAER Debris Flow

The map above displays estimates of the likelihood of debris flow (in %), potential volume of debris flow, and combined relative debris flow hazard.

Santa Barbara/Ventura Flooding at a Glance

  • 17 confirmed deaths related to the storms (These numbers are subject to change as the incident continues)
  • 13 missing people
  • At least 25 injured
  • 50 rescues via helicopter hoists have been performed during today’s search and rescue operations.
  • 1-6.5 inches of rainfall over the Thomas Fire area.
  • Search and rescue efforts still remain priority with approximately 75 percent of the primary search completed in the debris flow area.

If you liked the material in this blog, you can read similar material RedZone has covered here.

Sources

http://www.cnn.com/2018/01/09/us/southern-california-evacuations-rain-flooding/index.html

http://www.latimes.com/local/lanow/la-me-ln-rainfall-mudflow-20180109-story.html

http://santabarbara.onerain.com/map/?sensor_class=10|2880&view_id=5&view=8bc6e88f-eeab-4281-9d92-3d723016e945

https://landslides.usgs.gov/hazards/postfire_debrisflow/detail.php?objectid=178

Aerial photo over Kynsna area (Source: South African Red Cross)

Wildfires Rage Across South Africa’s Cape After Massive Winter Storm

Hundreds are left homeless and thousands remain evacuated after the strongest winter storm in decades assaulted Cape Town, South Africa, and continued across the southern region of South Africa known as the Western Cape. Numerous lightning strikes associated with the massive storm ignited wildfires that raged across hillsides, fueled by gusting and strong winds, even as nearby areas began to flood and were drenched by rain. Tuesday evening, June 6th, the storm began to impact the Western Cape. By Wednesday, thousands of residents along the major roadway N2, famously known as the “Garden Route”, were evacuated as wildfires blazed toward nearby neighborhoods. As of June 8th, 4pm PDT, nine deaths are attributed to the storm, home collapses, and wildfires.

Storm Impact & Wildfires in Area around Cape Town and Knysna (Source: Google Earth)

Storm & Wildfire Impacted Area around Cape Town and Knysna (Source: Google Earth)

Current Situation

The local media is referring to this as the “mother of all storms”. A compounding factor to the devastating impact to the region is the already poor housing covering much of the area. Shanty towns burn quickly and can also collapse simply due to the strength of the winds. Flood waters also washed away several communities due to non-permanent construction. Part of the evacuation process included a local hospital in Knysna had to move all personnel and patients due to the approaching wildfires. The rain now falling on the Knysna area will assist firefighting efforts to get the wildfires under control; however, the additional rains will increase the possibilities for mudslides in the area.

Activity of Wildfires in last 48 hours, centered on Knysna (Source: Advanced Fire Information System Viewer – AFIS)

Wildfire activity in last 48 hours, centered on Knysna (Source: Advanced Fire Information System Viewer – AFIS)

Recovery & Outlook

So far, reports indicate more than 150 structures were destroyed throughout 20 suburbs. Cape Town, fortunately, has restored approximately 90% of its power. Across the impacted area, staff are opening shelters and resource centers to assist those displaced. The rains received may help with a fraction of the drought situation, but Level 3 water restrictions remain in place. Wetting rains over a longer duration are needed to truly have an impact. Local volunteers are collecting donations of items such as food, water, blankets, and other basic necessities for those affected by this disaster.

Aerial photo over Kynsna area of wildfires (Source: South African Red Cross)

Aerial photo over Kynsna area (Source: South African Red Cross)

Read further

Live update stream: http://www.news24.com/SouthAfrica/News/live-knysna-evacuation-underway-20170607

http://www.bbc.com/news/world-africa-40199270

http://www.accuweather.com/en/weather-news/powerful-winter-storm-kills-at-least-eight-in-cape-town/70001884

http://www.cnn.com/2017/06/08/world/south-africa-fires/

http://www.aljazeera.com/news/2017/06/storm-kills-displaces-thousands-cape-town-170608052748704.html