Monday, June 24, 2013

Nagging Severe Risk (why Friday's storm was so strong - lessons learned)

82 F. high in the Twin Cities Monday.
82 F. average high on June 24.
84 F. high on June 24, 2012.

Showers and T-storms (some heavy to severe) into Wednesday night.

Basically dry Thursday into Saturday with a drop in temperature and dew point.




Jungles of Minnesota

Here's a vaguely personal question: do you have Doppler in your pocket? I'm not trying to insult you or sell you anything. I'm talking about the ability to call up radar and warning maps on your smart phone. We're not always in front of TV's or computer screens, but with the right app there's no reason to be surprised by a sudden tantrum from Mother Nature.

With the exception of Dakota county, outdoor sirens aren't sounded for severe thunderstorm warnings. And yet Friday's storms were historic, impacting far more Minnesotans than most tornadoes or even floods. The day is coming (soon) when we will each have our own personal warning systems (TV at home - smartphone enabled while mobile). The government won't save us - we need to take personal responsibility for our safety, and the safety of our families.

Severe storms bubble up again today & Wednesday, but sunnier, drier, less humid weather arrives Thursday into much of the weekend. Cool air aloft may set off PM clouds and showers by Sunday afternoon. Models show a cooling trend; 70s in time for the 4th of July?

And yes, it's a minor meteorological miracle that nobody was injured or killed during Friday evening's hurricane-like winds. We were very, very lucky.

Tuesday Severe Threat. There's a slight risk of large hail and damaging winds from the Dakotas and much of Minnesota to Des Moines, Chicago and Detroit, another region that needs to be monitored over northern New England. Map: SPC.

Flood Watches And Warnings. With recent heavy rains the local NWS office is upgrading some watches to warnings. If you live along a flood-prone river or stream you'll want to pay attention in the coming days. Here's the latest Flood Watch:

...THE FLOOD WATCH HAS BEEN UPGRADED TO A RIVER FLOOD WARNING
FOR THE FOLLOWING RIVERS IN MINNESOTA...

  SOUTH FORK CROW RIVER AT DELANO AFFECTING WRIGHT COUNTY
  CROW RIVER AT ROCKFORD AFFECTING HENNEPIN AND WRIGHT COUNTIES

...THE NATIONAL WEATHER SERVICE IN CHANHASSEN HAS ISSUED A FLOOD
WATCH FOR THE FOLLOWING RIVERS IN MINNESOTA...

  MINNESOTA RIVER AT MONTEVIDEO AFFECTING CHIPPEWA...LAC QUI PARLE
  AND YELLOW MEDICINE COUNTIES
  MINNESOTA RIVER AT HENDERSON AFFECTING LE SUEUR...SCOTT AND SIBLEY
  COUNTIES
  MINNESOTA RIVER NEAR JORDAN AFFECTING CARVER AND SCOTT COUNTIES
  MINNESOTA RIVER AT SAVAGE AFFECTING DAKOTA...HENNEPIN AND SCOTT
  COUNTIES

.THIS RIVER FORECAST IS BASED ON THE RAINFALL THAT HAS OCCURRED
OVER THE PAST FEW DAYS. ON AVERAGE WIDESPREAD 2 TO 4 INCHES
WITH LOCALIZED AMOUNTS OF 6+ INCHES HAS FALLEN ACROSS THE
MINNESOTA RIVER VALLEY. ANOTHER ROUND OF STORMS WILL FORM THIS
AFTERNOON AND INTO TONIGHT. RAINFALL AMOUNTS THROUGH 7 AM TUESDAY
WILL AVERAGE BETWEEN 0.75 AND 1.25 INCHES. IN ADDITION...WE ARE
EXPECTING ANOTHER ROUND OF STORMS DURING THE DAY ON TUESDAY AND INTO
TUESDAY NIGHT. THE FORECAST RAINFALL WITH THE ACTIVITY EXPECTED
TUESDAY AFTERNOON AND TUESDAY NIGHT HAS NOT BEEN INCLUDED IN THE
FORECASTS. SO THE ADDITIONAL RAINS COULD CAUSE RIVER LEVELS TO RISE
EVEN HIGHER THAN PREDICTED.

GIVEN THE UNCERTAINTY IN THE RAINFALL FORECAST FOR TODAY AND
TUESDAY...THERE IS STILL SOME UNCERTAINTY TO THE RIVER
FORECASTS AND WHETHER OR NOT LOCATIONS WILL REACH FLOOD STAGE.
AS CONFIDENCE INCREASES ON THE FORECASTS AND THE POTENTIAL FOR
FLOODING...FUTURE WARNINGS MAY BE ISSUED.

 
Lessons Learned From The June 21 Mega-Storm. Last Friday evening's bow echo, severe winds and flooding rains were a subtle (yet blunt) reminder that damage from severe thunderstorms can be even more extensive than a tornado touch-down. The latest edition of Climate Matters is here: "It wasn't a tornado, but hurricane force winds combined with a saturated ground that led to widespread damage and the largest power outage in Minnesota's history. Friday night's storm was the equivalent of a 15-mile-wide EF-0 tornado, and WeatherNation Chief Meteorologist Paul Douglas says it serves as a reminder that you need to take severe thunderstorms seriously."

Extra Severe. Imagery above from Friday evening's bow echo; reflectivity upper left showing rain and hail, radial velocity upper right shows a severe gust front as rain and hail-cooled air rushed east at 50 mph. A few thoughts from Friday's severe gust front:
 
* Sirens are not sounded for Severe Storm Warnings (with the exception of Dakota County).
 
* Tornadoes get more attention, but severe storms can be just as destructive. Damage is often more extensive, but not as severe as in a major tornado. To put things into perspective, the damage left behind from Friday's 70-80 mph gust front was roughly equivalent to an EF-0 tornado, one that was 15-20 miles wide.
 
* The supercell thunderstorm that morphed into a bow echo raced east at 50 mph, moving faster than the high-res models were suggesting. Winds gusted close to hurricane force across much of Hennepin County for 10-15 minutes. The persistence of the high winds, coupled with wet, saturated ground from early morning storms, helped to bring down even more trees.
 
* This rotating supercell was able to sustain itself, keeping the rain and hail-cooled gust front intact for several hours, prolonging the damage. A typical thunderstorm self-destructs after 30-45 minutes, but spinning supercells can protect the warm updraft, sustaining a storm for a long period of time.


Bow Echo. Click to activate loop. Here is a loop (GR2) of the severe thunderstorm that swept across the metro area Friday evening, becoming more severe as it pushed east of Lake Minnetonka toward South Minneapolis, whipping up a 70-80 mph gust front in the process.


Thundery Holding Pattern. Once again weather systems are creeping eastward across the USA, showers and T-storms, some strong to severe, will continue to flare up from the Midwest into the Great Lakes and New England. The southwest remains dry - nothing brewing in the tropics thru the 4th of July.


3 Dry Days In A Row? Don't get your hopes up too high. Our track record isn't very promising as of late, when storms and fronts seem to be spaced about 24 hours apart. Showers and T-storms linger into Wednesday, but ECMWF data (and other models) confirm a mostly-dry spell from Thursday into Saturday; probably the nicer, drier day of the weekend. A few showers are possible Sunday, temperatures on the cool side of average into the 4th of July holiday weekend. No big heat spikes for the 4th? Tell me you're really surprised.



Lightning Safety. After concern was raised about recent Little League baseball games played during questionable weather (lightning observed nearby) I wrote this note to an ump who asked me about criteria for calling off a game, and when it's safe to resume play. Here is my reponse:

"With the recent spate of severe and damaging thunderstorms impacting the metro area, I wanted to drop you a quick note and remind you and your colleagues that lightning-related fatalities are most likely at the very beginning and tail-end of an outdoor event. This is where we see the most lightning-related injuries and fatalities, not during the height of the storm, when heavy rain/hail is falling.
Here’s the problem: lightning can travel 8-10 miles in a horizontal direction. In fact every year people are struck with blue sky overhead, a thunderstorm on the distant horizon. The National Weather Service’s “30-30 Rule” has become a defacto standard in the weather business. When you can count 30 seconds between lightning and thunder it’s time to head for shelter; and wait 30 minutes after the last thunderclap before resuming safe play on the field.

From a National Weather Service link focused on Lightning Safety and Outdoor Sports Activities:
“Because electrical charges can linger in clouds after a thunderstorm has passed, experts agree that people should wait at least 30 minutes after the storm before resuming activities”.

I realize the wet spring has compressed the season, and players (and their parents) are anxious to get these games in and complete the season. However the overriding goal should be safe play and lowering weather risk. Any temptation to “push the weather” and get coaches, players (and spectators) out onto a ball field within 30 minutes of the last report of thunder is not only unsafe, but a potential disaster in the making. From a litigation standpoint, there’s a large and growing body of evidence that waiting 30 minutes significantly increases safety margins and helps to avoid lightning-related disasters. Taking a chance and resuming play within that 30 minute window is a recipe for fatalities, life-long, chronic, lightning-related injuries, and litigation.

As an interested parent who spent many long weekends at the local ballpark with my two son (checking Doppler on my smart phone more often than I would have liked) I have an interest in safe play and taking any and all steps to reduce the potential for weather-related tragedy."

- Paul Douglas, CBM Meteorologist. Founder of Media Logic Group.
 
Alberta Flood Volunteers: "People Have Really Come Together". Portions of Calgary are still underwater; this is reportedly the worst flooding Alberta, Canada has experienced in recorded history. CTV News has a story of the aftermath and clean-up operations underway: "As southern Alberta deals with the worst flooding in its history, volunteers and staff with the Canadian Red Cross say they are working around the clock to help those affected get through the crisis and begin the cleanup. Matt Baden, a Red Cross emergency response team lead, has been working at an emergency shelter in Blackie, just a few kilometres east of High River, the community that was hardest hit by the flooding. He says currently, the Red Cross is working to supply the evacuees at the shelter with the basic necessities, such as cots, blankets and hygiene kits, and to make people as comfortable as possible..."

Photo credit above: "A flooded downtown Calgary, Alberta is seen from a aerial view of the city Saturday, June 22, 2013. The two rivers that converge on the western Canadian city of Calgary are receding Saturday after floods devastated much of southern Alberta province, causing at least three deaths and forcing thousands to evacuate." (AP Photo/The Canadian Press, Jonathan Hayward)

iFetch Allows A Dog To Play Fetch On It's Own. Is it me, or is this just kind of sad. Who says technology is making us smarter? Gizmag.com has the story; here's the intro: "Playing fetch with your dog is surely one of life's high points. After a short while though, it can all get a bit tiring and just a tad boring. Your bouncing bundle of fun, on the other hand, would happily keep the game going for hours. Fortunately, technology is here to help. The iFetch from the Hamill family shoots out a ball for your dog to fetch, and when fido drops it in the opening at the top, it's fired back out again..."

 

TODAY: Steamy, risk of a few severe T-storms. Dew point: 72. High: 87

TUESDAY NIGHT: T-storms, locally heavy rain capable of minor flooding. Low: 73

WEDNESDAY: Still tropical. More numerous showers and T-storms. Dew point: 73. High: 86

THURSDAY: Warm sun, probably dry with a drop in humidity. Dew point: 66. Wake-up: 72. High: 89

FRIDAY: Clouds & sun, less humid. Dew point: 63. Wake-up: 69. High: 83

SATURDAY: Partly sunny, late PM showers far north. Wake-up: 65. High: near 80

SUNDAY: Sunny start, then midday clouds, few PM showers? Wake-up: 64. High: 75

MONDAY: Intervals of sun, drier again. Wake-up: 59. High: 79


Climate Stories...

Introducing The New Profession Of Extreme Weather Architect. Yes, the upward spike in T-storm winds, hail and flash flooding is already impacting the way some architects design homes to better withstand weather extremes. Here's an excerpt from Quartz: "Daniel Horn, a fresh New York architecture graduate, has launched a global competition around a tricky design question—what is the most aesthetic way to raise the elevation of an entire neighborhood block by eight to 10 feet? Call it extreme weather architecture. Horn, a 23-year-old graduate of the New York Institute of Technology (more on him below), is part of a boom in design competitions and urban reconstruction initiatives built around climate change. A rash of storms, drought and fires in recent years has ignited this contemplation of a new school of design cutting across cities and shorelines, homes and commercial buildings. The emerging class of architecture suggests the onset of a global design-and-construction industry worth tens of billions of dollars in the coming years..."

Photo credit above: "Mantoloking, New Jersey on March 22, 2013." Reuters/Lucas Jackson.

Obama Is Announcing Major New Climate Plans Tuesday. This Chart Explains Why. The Washington Post has the story - here's the intro: "On Tuesday, President Obama is expected to announce a couple major new steps to address global warming, including a plan to limit carbon-dioxide emissions from existing  power plants. But what’s the goal here? To put this all in context, take a look at this chart from the most recent Economic Report of the President, which shows the United States is nowhere near on pace to meet its short-term climate targets by 2020..."

Obama's Climate Plan Seen Putting Heat On Power Plants, Appliances. Here's a clip from a story at Politico: "...While the climate speech isn’t likely to touch on the Keystone XL oil pipeline, the controversial project that has spawned a massive opposition campaign among the president’s liberal base, it is expected to involve these measures:

1. Power plant clampdown
All eyes are on EPA, the federal agency in charge of writing and implementing what are likely to be some of the most controversial regulations in the president’s second term: limiting carbon emissions from both new and existing power plants. Heather Zichal, the White House energy adviser, suggested Wednesday that EPA is committed to moving forward with climate regulations for power plants, particularly from the fleet of coal-fired plants that have traditionally provided the bulk of the country’s electricity. Power plants are the biggest source of U.S. carbon emissions..."
 
Photo credit above: "In a highly anticipated speech, the president will outline his second-term climate plan." AP Photo

 
We Haven't Hit The Global Warming Pause Button. The Guardian has the story - here's an excerpt: "...In the 1980s and 1990s when air temperatures were warming in step with the overall warming of the planet, that was fine. However, over the past decade, the warming of surface air temperatures has slowed. At the same time, the overall warming of the planet has continued, and if anything it has accelerated. This has been difficult to reconcile for those who previously focused on surface air temperatures – what do we say about "global warming" now? The result is a spate of articles from the New York Times, Washington Post, The New Republic, and Der Spiegel, all of which get most of the facts right (including noting the warming of the oceans), but that all begin from the premise that "global warming" has slowed. It would be more accurate to say that global surface air warming has slowed, but the overall warming of the Earth's climate has sped up..."

Graphic credit: "Global heat accumulation from Nuccitelli et al. (2012)".
 
Climate Change And The Alberta Flood. Is there a connection? Here's an excerpt of a story at Maclean's: "...Meanwhile, there is the matter of the flooding in Alberta and to what extent that flooding might be said to have been caused by climate change. Jason Kenney says there’s no connection. Alberta hydrologist John Pomeroy says climate change was a factor. And Andrew Nikiforuk thinks this will prove a moment of realization for Albertans.
Albertans have also learned that climate change delivers two extremes: more water when you don’t need it, and not enough water when you do. The geographically challenged have also become learned, once again, that water travels down hill and even inundates flood plains.

So climate change is not a mirage. Nor is it weird science or tomorrow’s news. It is now part of the flow of daily life."
Photo credit: "This undated photo provided by the Calgary Flames shows the inside of the Calgary Saddledome in Calgary, Alberta. The Saddledome, home to the National Hockey League's Calgary Flames, was flooded up to the 10th row, leaving the dressing rooms submerged. The two rivers that converge on the western Canadian city of Calgary are receding Saturday, June 22, 2013 after floods devastated much of southern Alberta province, causing at least three deaths and forcing thousands to evacuate." (AP Photo/Calgary Flames).

1 comment:

  1. Weather alerts should really be on the lookout for these sudden bursts of violent weather, especially if the area involved is prone to the nastier types such as tornadoes and heavy flooding. That way, people can evacuate earlier or prepare to reinforce their house beforehand.

    Lino @ Arrys Roofing

    ReplyDelete