Dorian May Strengthen Into a Category 4

Our winters can be brutal, but as cold and snowy as it gets we never have to evacuate our homes. Yes, it’s our birthright to gripe about the weather, but all it takes is one Texas-size storm to provide timely perspective.

Meteorologists do a better job predicting hurricane track than intensity. Water temperatures near the Bahamas are 1C warmer than average, and Dorian may strengthen into an extreme Category 4 storm before approaching the Atlantic coastline of Florida on Labor Day. Models are slowing the forward motion of the storm; it may sit and spin just offshore for 2-3 days, compounding damage from waves, wind and flooding rains. In recent years far more people have been killed by inland flash flooding than the storm surge, a sudden rise in water ahead of the storm’s eye.

One positive development: model runs late Friday kept the worst of the wind, surf and heavy rainfall (just) offshore. It’s premature for anyone to let their guard down, but maybe Florida will catch a break.

A shower is possible today; Sunday looks sunnier and milder with a shot at 80F Labor Day before T-storms gang up on us late Monday into early Tuesday. No drama close to home.

Check the blog for frequent updates on Dorian.


10-meter accumulated wind gust track with Dorian above courtesy of WeatherBell.


Northern Lights. CNN.com has a reminder that we may (MAY!) get lucky with a glimpse of the Aurora Borealis this weekend. Remember, this only works at night, well away from city lights: “The aurora borealis will be visible this weekend in parts of several northern US states, according to the National Oceanic and Atmospheric Administration. The light show, forecast for Saturday and Sunday, is a result of geomagnetic storm activity, NOAA says. The luminous celestial glow occurs in both hemispheres, due to electrons from the solar wind colliding with Earth’s atmosphere, the Geophysical Institute says…The best time to see the aurora is a couple hours before or after midnight with a clear, dark sky creating the best conditions…”

Check out the latest Aurora Forecast from the University of Alaska/Fairbanks.




Better Than Average – for a Major Holiday. In spite of patchy clouds and a stray shower over the southern half of Minnesota and a few late-day T-storms on Labor Day (the warmest day of the bunch) the weather doesn’t look half bad. Sunday should be the sunniest, driest day statewide. Maps above: Praedictix and AerisWeather.



Monday: First Mille Lacs County Tornadoes Since 2011. There were 2 confirmed touchdowns, both relatively small/weak tornadoes. But still…Details from the Twin Cities National Weather Service: “Scattered thunderstorms moved across central Minnesota on the evening of August 26th and two of those storms produced brief tornadoes in Mille Lacs county.  An EF0 occurred south of Onamia, while the second touched down southeast of Milaca and was rated an EF1. These were the first tornadoes to occur in Mille Lacs county since July 30, 2011.”


What to Do Before a Hurricane. I wrote a story for The Washington Post’s Capital Weather Gang; here’s an excerpt: “...If evacuation seems likely, have a “go-bag” ready with clothing, extra cash and credit cards, essential medications and any documents you may need on the road. In the wake of a storm, the power may be out, and it may be difficult to travel. Create a Family Emergency Plan in advance. Don’t count on electricity, fresh food and water or gasoline in the wake of a major hurricane. Have at least a week’s worth of nonperishable food and water on hand. You don’t have to become a doomsday prepper, but planning ahead will save you pain and aggravation. Check on neighbors to make sure they have a plan, and make sure pets have sufficient food and water...”


Praedictix Briefing: Issued Friday, August 30th, 2019:

  • Dorian has continued to strengthen as it moves east and northeast of the Bahamas. As of 11 AM EDT/AST, Dorian had sustained winds of 110 mph (a Category 2 hurricane) and was moving to the northwest at 10 mph.
  • This storm will continue to move west-northwest to northwest over the next few days, impacting the northwestern Bahamas this weekend into early next week with destructive winds, very heavy rain, and a storm surge that could be 10-15 above normal tides. Hurricane Watches have been issued for this region. The storm will continue to strengthen as well, becoming a Category Four hurricane during the weekend.
  • The storm will see its forward progress slow as we go through the weekend into next week, which has pushed back the potential timing of landfall in Florida to Monday Night at the moment. There are also still some questions into next week on the exact path of the system, as at some point it will turn to the north. Whether this occurs over Florida or just off the coast, however, Dorian will still be a major and dangerous system, with the potential of storm surge, life-threatening rain and flash flooding, and winds over 100 mph. A prolonged period of hazardous weather appears likely early/mid-next week across the state.
  • Florida Governor Ron DeSantis has already declared a State of Emergency ahead of Dorian, urging residents to prepare. You can visit http://www.floridadisaster.org to find information on emergency preparedness, shelters, road closures and evacuation routes. You can also find the website for your Florida county emergency management agency at https://www.floridadisaster.org/counties/. Now is the time to prepare, as tropical storm force winds could start to impact the state Sunday, which would start to make last-minute preparations difficult ahead of the storm. Know if you are in an evacuation zone, and make sure to stay up to date with the latest forecasts and any advice local government officials give.

Dorian As Of Friday Morning. Dorian has continued to strengthen east and northeast of the Bahamas over the past 24 hours, and as of Friday morning was almost at major hurricane strength (Category 3+ with winds of at least 111 mph). The 11 AM EDT/AST update from the National Hurricane Center had Dorian as a Category 2 hurricane with 110 mph. The center of Dorian was located about 480 miles east of the northwestern Bahamas, or 660 miles east of West Palm Beach, FL, moving to the northwest at 10 mph. Hurricane-force winds extend outward up to 25 miles from the center of Dorian, with tropical-storm-force winds extending outward 105 miles.


Dorian Track. Dorian will continue to strengthen over the next few days as it moves off to the west-northwest and northwest and is expected to become a Category 4 hurricane (winds of at least 130 mph) this weekend. The storm is also expected to slow down forward momentum as we head into the weekend as steering currents aloft essentially collapse. The current track would have the storm approach and cross the northwestern Bahamas Sunday into Monday. The slower movement means that Dorian won’t make landfall until Monday Night or Tuesday along the eastern Florida coast at the moment as a major Category 4 hurricane with sustained winds around 140 mph possible. Models currently indicate that Dorian will turn northward next Tuesday/Wednesday. The big question is when this turn occurs at the moment, with some models showing it over the Florida Peninsula while others show it occurring off the eastern Florida coast. Either way, this system will continue to move at a slow pace and impact portions of Florida through the middle of next week with strong winds, heavy rain, and storm surge.


Potential Strength. Many models continue to show Dorian staying strong over the next few days while the storm moves over very warm conditions. Dorian is likely to remain a dangerous, major hurricane until landfall early next week across Florida.


Hurricane Watches. Earlier this morning Hurricane Watches were issued for the northwestern Bahamas. This indicates that hurricane conditions are expected across the watch area within the next few days, with tropical-storm-force winds expected within about 48 hours.


Tropical Storm Force Wind Timing. This graphic gives a good timing as to when winds could start to reach tropical storm force (39+ mph) with Dorian, which will start to make last-minute preparations difficult ahead of the storm. Tropical storm force winds look to start impacting the northwestern Bahamas as we go throughout the day Saturday, and could reach the eastern Florida coast by Sunday morning.


Potential Wind Gusts. Note that this graphic is highly dependent on the overall track of the storm, but with the current expected track and strength of Dorian, some areas near the Florida coast and toward Okeechobee could see wind gusts of 100+ mph as Dorian approaches and makes landfall Monday/Tuesday next week. I would expect some changes in this graphic depending on the overall track over the next few days.


Life-Threatening Storm Surge. As Dorian moves toward the Bahamas and the Southeast water will be pushed toward the coasts, which (especially at high tide) will cause the potential for a life-threatening rise in water especially in areas of onshore winds. In the Bahamas, this rise in water levels could be by as much as 10-15 feet above normal tide levels and accompanied by large, destructive waves near the coast. While storm surge and coastal flooding are also likely across the eastern Florida coast, it is a little too early to determine exact impacts.


Rain Potential. Dorian will also bring the potential of heavy rain along with it, especially as the storm slows down across the Bahamas and the southeastern United States. Models continue to indicate the potential of 20”+ of rain along the track of the storm, which could lead to life-threatening flash flooding across these areas. Here’s a breakdown of potential rainfall amounts at the moment from the National Hurricane Center through the middle of next week:

Northwestern Bahamas and coastal sections of the Southeast United States…6 to 12 inches, isolated 18 inches.
Central Bahamas…1 to 2 inches, isolated 4 inches.


Summary. We are continuing to track Hurricane Dorian, which will become a major hurricane later today and is likely to remain at that strength through early next week. The storm will track through the northwestern Bahamas this weekend into early next week, bringing destructive winds, very heavy rain capable of flash flooding, as well as a life-threatening storm surge that could be 10-15 feet above normal tide levels. Hurricane Watches have been issued for the northwestern Bahamas, indicating that tropical storm force winds are expected across the region in about 48 hours. There are still some question marks as to when the storm will turn north next week which will determine whether Dorian makes landfall in Florida or remain barely offshore. Nevertheless, residents and facilities along the eastern Florida coast and across the Florida peninsula should be preparing for a major hurricane to impact the region early/mid-next week, capable of destructive winds, storm surge along the coast, and very heavy rain, and be prepared to evacuate if orders are issued. We’ll continue to provide regularly scheduled briefings throughout the holiday weekend with the very latest on Dorian to keep you and your facilities informed with the latest.

D.J. Kayser, Meteorologist, Praedictix


How to Avoid Hoaxes and False News About Dorian. Poynter has some good reminders: “…The five points listed below can also serve fact-checkers around the globe who are not on Hurricane Dorian’s path but will need to report about it.

  1. Make sure you know where to find official information

In the United States, one of the best sources of reliable information is the National Hurricane Center (NHC). Its Hurricane Specialist Unit (HSU) maintains a continuous watch on tropical cyclones and areas of disturbed weather within the North Atlantic and eastern North Pacific basins. From them, you can expect “analyses and forecasts in the form of text advisories and graphical products” (in English)...”



Why You Don’t Want To Be in a Vehicle During a Tornado: Exhibit A. Thank you Jay Leno and CNBC, for showing us what 100-200 mph winds can do to a car or truck: “Jay Leno experiences some of the world’s toughest cars in the Season 5 premiere of “Jay Leno’s Garage!” Catch the exclusive look at Jay putting a storm chaser’s tornado-proof vehicle to the test against a jet! Then, don’t miss all new episodes of “Jay Leno’s Garage” Wednesdays at 10P ET on CNBC.”


Smog and Sadness: Study Suggests Link Between Air Pollution and Psychiatric Disorders. Here’s an excerpt from Study Finds: “Could the very air we breathe have an impact on our mental health? That’s the suggestion coming out of a new international study conducted in the United States and Denmark. After analyzing long-term data sets from both countries, researchers from the University of Chicago say they have identified a possible link between exposure to environmental pollution, specifically polluted air, and an increase in the onset of psychiatric and mental health problems in a population. According to the findings, air pollution is associated with increased rates of depression and bipolar disorder among both U.S. and Danish populations. That association was actually found to be even greater in Denmark, where poor air quality exposure during the first 10 years of a person’s life was found to predict a two-fold increase in the likelihood of developing schizophrenia or a personality disorder...”

File image: Reuters.


NASA Cameras Track Amazon Fires. Big Think has a post; here’s a clip: “You don’t need eyes to see the massive fires raging in the Amazon. An infrared camera fitted on a satellite will do. This movie, based on data collected from 8th to 22nd of August by the Atmospheric Infrared Sounder (AIRS) on NASA’s Aqua satellite, shows carbon monoxide (CO) levels at 18,000 feet (5.5 km) above South America. The colours denote the density of carbon monoxide, from green (approximately 100 parts per billion by volume) over yellow (app. 120 ppbv) to dark red (app. 160 ppbv). Local values can be much higher. Each separate shot is the average of three days’ worth of measurements, a technique used to eliminate data gaps...”


BMW Unveils Vehicle with “Blackest Black”. I had no idea. Here’s an excerpt from dezeen.com: “BMW has released a Vantablack version of its X6 coupé, which has been spray-painted with “the world’s blackest black” pigment that absorbs over 99 per cent of light. Inventors of the Vantablack technology, Surrey NanoSystems, collaborated with creative agency Levitation 29 to coat BMW’s latest X6 coupé with a sprayable version of the pigment. According to the German car brand, the BMW VBX6 is the “first and only vehicle in the world” to feature a Vantablack VBx2 coating, which almost entirely removes all reflections…”


Do You Have What it Takes to be an NFL Taste Tester? CNN Travel explains: “It’s a dream and a nightmare rolled into one, then battered and fried and topped with sriracha mayo. Pickswise, a free sports betting site, is offering one NFL fan the coveted — and possibly dangerous — position of NFL food tester.  Technically it’s a contest, since you don’t need any skills to be chosen for the role. What you do need is a tolerance for large crowds and even larger amounts of fried and sauced stadium food. A general affinity for football would probably help, too.  “The job description includes travelling to NFL stadiums to taste the finest tacos, nachos, burgers, hot dogs and sandwiches the league has to offer…”


75 F. high yesterday in the Twin Cities.

78 F. average high on August 30.

77 F. high at MSP on August 30, 2018.

August 31, 1949: The earliest snowfall on record for Minnesota occurs on this date. A trace of snow is recorded at the new Duluth airport. (I almost censored this nugget).

August 31, 1947: A tornado hits Le Center, killing one person.


SATURDAY: More clouds, few showers central and south. Winds: SE 3-8. High: near 70

SUNDAY: Lukewarm sunshine, a nicer day. Winds: S 5-10. Wake-up: 58. High: 77

LABOR DAY: Warm sun, few T-storms later. Winds: SW 5-10. Wake-up: 63. High: 81

TUESDAY: Morning showers, then slow clearing. Winds: NW 10-20. Wake-up: 66. High: 76

WEDNESDAY: Plenty of sunshine, pleasant. Winds: S 7-12. Wake-up: 55. High: 74

THURSDAY: Showery start, then drying out. Winds: NW 10-15. Wake-up: 58. High: 75

FRIDAY: Mostly cloudy, windy and cooler. Winds: NW 15-25. Wake-up: 56. High: 68


Climate Stories….

Politics of Climate Change Put Corporations in a Tough Spot. The Associated Press has perspective: “The polarizing politics of climate change have forced companies to choose between supporting the Trump administration’s deregulation policies that could boost profits or opposing them to win over environmentally conscious consumers. That dynamic played out again Thursday when President Donald Trump’s Environmental Protection Agency sought to revoke regulations on methane gas emissions from oil facilities. British Petroleum, ExxonMobil and Royal Dutch Shell voiced opposition to the plan but smaller oil and gas companies welcomed the possibility. Before that, it was the auto industry grappling with a proposal to loosen fuel economy requirements. And this summer, it was electric utilities dealing with lower pollution standards for coal-fired power plants…”

Image credit: Yale Climate Connections.


What 500,000 Americans Hit by Floods Can Teach Us About Climate Change. The Guardian reports: “…Since 2010, I have been researching and writing about sea-level rise. During that time the predictions for just how high the water might reach by 2100 have, in many places, more than doubled. Meanwhile, from 2010 to 2017 nearly 500,000 Americans filed flood insurance claims, and hundreds of thousands more experienced flooding first-hand. When you compare the claims filed during, say, the eight years of Reagan’s presidency to those mentioned above the numbers more than double. Which is to say for many living in low-lying areas the climate crisis is already here. One of the things I remember most clearly from my early research trips to rural flood-prone communities is that residents told me how alone they felt. Most knew of no other place whose suffering was somehow analogous to their own, or other people they might consult to learn how to tackle their flooding problem...”

2012 Duluth flood file image courtesy of AP.


Investors Need to Know About Climate Risks. Business Insider has the post; here’s an excerpt: “…SEC regulations that require disclosure of climate risks are already on the books; what’s lacking is the will to enforce them. While the act improves the data reported, it has no provisions for enforcement. That’s also the problem with the existing regulations: The SEC has done nothing to enforce them. It is no secret that the climate crisis threatens business as usual. Back in 2008, the insurance industry identified climate change as the No. 1 risk facing the industry. And a hotter, wilder climate is likely to devalue many assets — including municipal bonds. So, in 2010 the SEC issued interpretive guidance to reinforce its existing risk disclosure requirements...”


Hurricanes and Climate Change. The American Association for the Advancement of Science connects the dots:

  • The five costliest U.S. Earth-system disasters (including earthquakes, volcanic eruptions, fires, and all kinds of extreme weather) have all been hurricanes, and all five have occurred within the past 15 years: Harvey (2017), Katrina (2005), Sandy (2012), Irma (2017), and Maria (2017). 1
  • Hurricanes get their energy from ocean heat; the warmer the water is, the stronger a hurricane can get. More than 90% of the excess heat trapped in the climate system due to human-caused global warming has gone into the oceans, providing the added energy driving recent hurricanes’ extreme wind intensities and the increased evaporation that has resulted in associated torrential rainfall. 2
  • Globally, the last few decades have seen a growing proportion of strong hurricanes and a corresponding shrinking proportion of weak ones. Specifically, from 1975 to 2010, the proportion of Category 4 or 5 hurricanes (the highest wind speeds) increased by 25-30 percent for every 1 degree Celsius increase in global temperature due to human causes, resulting in a near doubling of the proportion of those most intense hurricanes. 3


Welcome, Greta: Climate Nexus has headlines and links: “Swedish climate activist Greta Thunberg arrived in New York City Wednesday, greeted by a cheering crowd as she capped off her two-week journey in a sailboat across the Atlantic. The 16-year-old Thunberg, who carried her “skolstrejk för klimatet”–“school strike for climate”–sign off the boat with her, is in New York to attend the United Nations climate summit next month. Thunberg, who began striking outside of Swedish parliament for climate action one year ago this month, chose to voyage on the emissions-free racing sailboat to reach New York to avoid the carbon emissions from flying. “This is not something I want everyone to do,” she told a crowd of media, youth activists, and well-wishers Wednesday. “It is insane that a 16-year-old would have to cross the Atlantic Ocean to make a stand…The climate and ecological crisis is a global crisis, the biggest crisis that humanity has ever faced, and if we don’t manage to work together and to cooperate and to work together despite our differences, then we will fail.” (New York Times $, AP, Washington Post $, The Guardian, CNN, NPRThe Verge).


The Mysogyny of Climate Deniers. Picking on a teenage girl? The New Republic explains what may really be going on here: “…While these examples might feel like mere coincidence to some, the idea that white men would lead the attacks on Greta Thunberg is consistent with a growing body of research linking gender reactionaries to climate-denialism—some of the research coming from Thunberg’s own country. Researchers at Sweden’s Chalmers University of Technology, which recently launched the world’s first academic research center to study climate denialism, have for years been examining a link between climate deniers and the anti-feminist far-right. In 2014, Jonas Anshelm and Martin Hultman of Chalmers published a paper analyzing the language of a focus group of climate skeptics. The common themes in the group, they said, were striking: “for climate skeptics … it was not the environment that was threatened, it was a certain kind of modern industrial society built and dominated by their form of masculinity...”


Surge in Young Republicans Worried About the Environment – Study. Reuters has details: “A growing majority of U.S. Republicans, especially younger voters, are worried that human behavior is damaging the planet, according to a survey of global attitudes to the environment conducted by an Amsterdam-based polling agency…The new report by Glocalities, which canvassed views worldwide, showed the number of U.S. Republicans who said they “agreed” or “strongly agreed” with the statement “I worry about the damage humans cause the planet” rose by 11 percentage points to 58% between 2014 and 2019. The number of Republican voters aged 18-34 who are worried about the issue rose by 18 percentage points to 67%, said the poll, which also showed a 10 percentage point increase among all U.S. Republicans who said they tried “to live eco-consciously”…”


Can We Survive Extreme Heat? A story at RollingStone caught my eye; here’s an excerpt: “…As the mercury rises, people die. The homeless cook to death on hot sidewalks. Older folks, their bodies unable to cope with the metabolic stress of extreme heat, suffer heart attacks and strokes. Hikers collapse from dehydration. As the climate warms, heat waves are growing longer, hotter, and more frequent. Since the 1960s, the average number of annual heat waves in 50 major American cities has tripled. They are also becoming more deadly. Last year, there were 181 heat-related deaths in Arizona’s Maricopa County, nearly three times the number from four years earlier. According to the Centers for Disease Control and Prevention, between 2004 and 2017, about a quarter of all weather-related deaths were caused by excessive heat, far more than other natural disasters such as hurricanes and tornadoes...”

Graphic credit: NASA GISS.


Climate Change is Shifting Europe’s Flood Patterns, and These Regions are Feeling the Consequences. InsideClimate News examines the observed shift in weather patterns: “Global warming is driving big changes in floods across Europe by fueling the atmosphere with more moisture and changing the path and speed of rain storms, new research shows. In some areas, that means more rainfall and surging rivers that could overwhelm levees if communities don’t plan for increasing flooding. Other regions have seen a decline in rain and snow, which sets up a different challenge: as flood risk there decreases, it could discourage investments in defensive measures, leaving communities vulnerable to less frequent but still damaging extreme storms. The study shows “clear flood risk patterns across Europe that match the projected impacts of climate change,” said Günther Blöschl, lead author of the study, published Wednesday in the journal Nature, and director of the Centre for Water Resource Systems at the Vienna University of Technology...”