World Storm Surge Record Set to Fall? Aberrant Ita Prepares to Slam Queensland With 155+ mph Winds After Spurring Historic Solomon Islands Flooding

 

Super intense ITA off Australia

(Another Case of Near-Perfect Symmetry. Super-intense ITA strengthens to a super-intense 155 mph storm off Australia on April 10. Image source: NOAA)

The ghosts of record Pacific Ocean heat content may well be coming back to haunt us…

Very powerful near Category 5 Ita is now bearing down on the Australian Coastline. Regions near where the center makes landfall, projected to be near Cape Flattery, could experience 155 mph sustained winds with gusts in excess of 185 mph and storm surges in excess of 25 feet. Interests throughout North Queensland should remain abreast of what is a very powerful and dangerous storm capable of producing record or near record effects.

(For reference, a category 5 storm has a wind speed intensity of 156 mph or greater.)

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An outrider of an El Nino pattern that appears to be gradually emerging and strengthening in the Tropical Pacific, Ita had her stormy beginnings near the archipelago of the Solomon Islands. There, what at first started as a tropical disturbance dumped three days of torrential rainfall over the island chain, setting off worst-ever floods on record, washing away hundreds of buildings, and leaving more than 50,000 people homeless.

Major rainfall events are not uncommon in the Solomons. But what occurred as a result of current and abnormally intense heat-spurred Pacific Ocean convection is. For the massive shield of thunderstorms that spawned Ita also dumped one meter (1000 mm or 39.4 inches) of rainfall during a three day period over some sections of this tropical island chain. The far-reaching floods ruined roads, bridges, buildings and forced the cessation of strip mining operations in interior sections.

Solomon Islands ITA

(Thunderstorms associated with the newly forming Ita boil over the Solomon Islands on April 3rd and 4th. Some locales received single-day rainfall totals in excess of 18 inches with three day measures topping 1 meter. Image source: LANCE-MODIS.)

The Solomon Islands lie just east of New Guinea and are on the southern edge of what is currently a very deep, hot pool of water — one that appears to be in the process of rushing eastward. There, over waters ranging from 85 to 87 degrees Fahrenheit (29-30 degrees Celsius, or about 1-2 C above average), Ita had her genesis in a shield of convection forming along the hot pool’s southern flank.

Slow Westward Trek

After lingering for days over the Solomons, Ita gradually shifted southwestward, churning  on into the Coral Sea and reaching category 1 intensity by April 8th. Water temperatures throughout the region remained well in excess of 80 degrees, more than enough to fuel rapid intensification. By late April 9th, many models showed Ita potentially reaching category 4 or 5 intensity before roaring into northern Queensland.

Concerns were raised about both projected storm intensity and projected track. Clockwise circulation of a slow-moving but very powerful storm could pile a very significant storm surge along the Queensland cities of Port Douglas and Cairns. Northern locations could experience very intense and prolonged storm conditions including heavy rainfall, extreme coastal flooding, and winds in the range of 90 to 155+ mph over a tightly compact zone.

Cape Flattery, Cooktown and Port Douglas, sparsely populated towns of between 2,000 and 3,000 residents, respectively, are likely to bear the brunt of the storm. But Cairns lies only a little further south along the storm track and boasts fully 150,000 residents — a more densely populated region that could also see extreme impacts.

Bombification

By early April 10th, favorable environs and extremely warm water temperatures in the Coral Sea had resulted in the rapid intensification predicted. By 1600 Eastern Time in the US, Ita had bombed out to a 155 mph monster storm with a lowest central pressure around 921 mb, exploding from a Category 1 to a near Category 5 storm in less than 48 hours, as it headed toward the Australian coastline at an excruciatingly slow pace of 6 mph SSW forward motion.

It’s worth noting that a 921 mb reading is very low and may justify a new winds speed of closer to 165 mph or more considering how compact this storm. Early model runs had projected peak intensity at 920 mb and around 165 mph wind speeds. That said, ITA remains over open water and retains a very compact wind field, so further intensification is possible before land interference begins to disrupt circulation.

Even now, conditions may seem disturbingly tranquil along the coastline. Winds there are currently running in the range of about 20-30 mph. But gale force winds lurk about 100 miles offshore and the intense, hurricane force, winds are not fare behind. The most intense winds, of up to 155 mph sustained with 185 mph gusts, are in a tight band just about 10-20 miles from the center. It is regions within this band of clockwise onshore flow where most damaging effects are likely to be witnessed.

ITA projected path

(Most recent projected path of Ita. It’s worth noting that the Australian Bureau of Meteorology puts Ita at 907 mb and Category 5 status. This conflicts with NOAA’s 921 mb estimate. Image source: Australian Bureau of Meteorology.)

Ita is expected to maintain Category 4-5 intensity all the way through to land-fall sometime tomorrow. As such, storm surge flooding in excess of 25 feet is likely near where the center makes landfall. A storm of similar strength, Typhoon Mahina, brought a 45 foot storm surge ashore near Bathurst Bay in 1899. It is the same region where Ita is expected to make landfall sometime tomorrow.

This storm surge of 45 feet ties Bangladesh for the highest storm surge on record anywhere in the world.

Mahina made landfall with a minimum central pressure of 914 mb. Ita would only need to drop another 10 mb to exceed that mark. But, if it does, a world storm surge record could be set to fall.

UPDATE: Ita shows some slight weakening in both satellite and pressure estimates. Pressures (NOAA) as of about 7 PM were around 926 mb with maximum sustained winds still estimated in the range of 150 to 155 mph. Australia’s Bureau of Meteorology maintains ITA at 907 mb and CAT 5. Still a very powerful storm.

UPDATE: As of 9 PM EST, US, Ita continued to show some signs of slight weakening. NOAA now shows Ita as a 931 mb storm, while Australia’s Bureau of Meteorology puts it at 914 mb. No cause for comfort, as yet, since these pressure estimates are well within the range of a strong CAT 4 or CAT 5 storm.

Perhaps more ominous, however, is a slight job to the south. Too early to call but if a more southerly track continues, locations such as Cairns may be in for more of an impact. Still too early to call.

ITA gale force winds on shore

As per the recent VMAX wind profile Ita’s gale force winds are now on shore. Measurements are in knots. In this measure maximum sustained winds are just into CAT 5 status (138 kts). Image source is NOAA.

UPDATE: Slow strength degradation continues pushing Ita into strong CAT 4 status. NOAA shows 937 mb and ABM shows 922 mb at 11 PM. Wind strength remains between 145 and 150 mph max sustained. Southward jog continues as it appears possible Ita may skirt the coast.

UPDATE: Ita came ashore as a Category 4 storm with effective one minute sustained winds in excess of 135 mph and a ten minute sustained wind of 120 mph near Cape Flattery in Queensland. Pressures at landfall were in the range of 935 to 948 mb. Ita has continued to track just inland and is now just west of Cooktown. Interaction with land has continued to degrade Ita, which as of 12 PM EST was estimated at Category 3 intensity.

 

Links:

Australian Bureau of Meteorology

LANCE-MODIS

NOAA

ITA Heads for Australian Landfall

ITA Public Advisory

ITA Wrecks Havoc in Solomon Islands

Beastly ITA

Monster Kelvin Wave Emerging in the Pacific

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Mangled Jet Stream Brings Worst Storms in Five Decades to Sichuan China; Approach of Super Typhoon Soulik to Result in Hybrid Rain Superstorm?

A persistent south-north flow of the Jet Stream has dredged moisture up from the Indian Ocean, India and Bangladesh and deposited it in a deluge that has persisted over Sichuan, China for at least the past five days. Rainfall in many areas were the worst seen since weather records began in 1954. In one example, the city of Dujiangyan experienced 37 inches of rainfall over the course of 40 hours.

The floods forced nearly 100,000 people to evacuate and have impacted at least 2 million people across the region. Over 200 people are feared dead or missing. With some towns buried under as much as 20 feet of water, thousands of homes and buildings have been destroyed or damaged with transportation brought to a stand-still in many of the effected regions. In hard-hit Dujiangyan, a local resort was buried when a hillside collapsed, burying the area to tree-top level in mud and debris and spurring the evacuation of 352 tourists. Raging floodwaters also caused a nearby bridge collapse that sent at least six vehicles into raging flood waters.

In the video below, provided by KIDgrownup, we can see the raging floodwaters washing away buildings and heavy equipment as people flee the disaster site:

Changed Jet Stream Causes Dangerous, Persistent Weather Pattern as Super Typhoon Approaches

A dwindling, but still significant, number of media sources continue to claim that we cannot attribute single events such as the most recent Sichuan Floods to climate change. Unfortunately, this claim is simply untrue. Climate is a measure of weather over a given area during a long period of time. As climate changes so does the weather. In Europe, for example, major flood events are now twice as likely as they were forty years ago. This 100% increase in floods can be directly attributed to changes in Europe’s climate and, as such, fully 50% of each new major flood is, therefore attributable to climate change. And the fact that the most extreme floods are getting more extreme can also be attributed to climate change. In this case, saying a single record flood event, like the current Sichuan flood, cannot be attributed to climate change is at least 50% untrue. Would a flood like this have occurred, eventually, if climate hadn’t changed? Probably. But it likely would have happened 50, 100, 200 years or more later. Would it have happened this year, the way it did, without climate change? Absolutely not.

At the micro level, we can also look at weather patterns and clearly point out how they are not normal and how they’ve changed as a result of human-caused climate impacts. In the example of this week’s Sichuan Floods, the Jet Stream created conditions where heavy rains, so far, have stalled over Sichuan to inundate the region.

Sichuan Floods July 8

(Sichuan Floods, July 8. Image source: Lance-Modis)

In the above image we can see a thick blot of clouds hovering over Sichuan in Central China. This dense band of clouds is the result of a cut off upper air flow of the Jet Stream forming a strong, persistent upper level disturbance. To the south, we can see a broad band of clouds and moisture being drawn into the system from the Indian ocean and over India, Bangladesh, Thailand and Vietnam. To the east, a tropical system in the Korean Sea also contributes moisture to feed this large storm.

What is most unusual about this particular weather pattern is that it doesn’t move. And we can see this when we switch to today’s Lance-Modis shot. The below image is 4 days later than the July 8 shot. But the storm over Central China has hardly budged.

Sichuan Floods July 11

(Sichuan Floods July 11. Image source: Lance-Modis)

In this shot, the cut off upper level flow in the Jet Stream remains, the dense cloud pack over Central China remains, the strong upper level low remains, and the moisture flow from the Indian Ocean and related regions remain. Ominously, the only marked difference in this shot is the looming approach of super typhoon Soulik from the China Sea. This major typhoon packs winds in excess of 140 miles per hour and could cause severe damage to Taiwan. However, it’s the ability of this system to deliver moisture into an already moisture rich upper level air flow that may result in even worse conditions for Eastern and Central China over the next few days as the storm is projected to make landfall in Eastern China, then track as far as 200 miles west of Shanghai. At this point, some weather models, including the ECMWF ensemble, show Soulik getting absorbed by the cut-off upper level low now parked over China. Were this to happen, the resulting rain event could be far more substantial than even the record floods seen over the past few days.

The Climate Change Link To Extreme Weather

So how did climate change create the conditions in which this dangerous situation emerged?

  1. The upper level Jet Stream was caused to meander due to a climate change induced loss of sea ice and summer snow cover.
  2. These changes resulted in a slower progression of weather patterns and more cut-off upper level disturbances.
  3. The added atmospheric heat content added both moisture and instability, adding fuel for storms like this one.
  4. Increased ocean temperatures made moisture and heat delivery from ocean systems and tropical cyclones more likely.

Without these conditions, the Sichuan floods were unlikely to have happened with such force, violence and to have been so persistent and long-lasting. And now, a bad situation is made worse via the ocean delivery of a super typhoon, just one of many more frequent storms to plague this region over the last 40 years. An increased frequency a recent scientific study also attributes to climate change.

Hybrid rain superstorm to form over China? Hopefully, not. But, at this point, things aren’t looking too good.

Links:

Lance-Modis

Rainstorms Flood Sichuan China

China Floods Death Toll Rises

Taiwan Evacuates 2,000 Tourists as Super Typhoon Soulik Looms

ECMWF

 

 

 

 

 

 

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