Volcanic Winter

By: Dr. Jeff Masters , 1:18 PM GMT on April 24, 2009

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"The sun was dark and its darkness lasted for eighteen months; each day it shone for about four hours; and still this light was only a feeble shadow; the fruits did not ripen and the wine tasted like sour grapes." As this Michael the Syrian quote regarding the weather of 536 A.D. demonstrates, a climate catastrophe that blots out the sun can really spoil your day. Procopius of Caesarea remarked: "During this year [536 A.D.] a most dread portent took place. For the sun gave forth its light without brightness. and it seemed exceedingly like the sun in eclipse, for the beams it shed were not clear." Many documents from 535 - 536 A.D.--the time of King Arthur in Britain--speak of the terrible "dry fog" or cloud of dust that obscured the sun, causing widespread crop failures in Europe, and summer frosts, drought, and famine in China. Tree ring studies in Europe confirm several years of very poor growth around that time, and ice cores from Greenland and Antarctica show highly elevated levels of atmospheric sulfuric acid dust existed.

Though some scientists believe the climate calamity of 535-536 A.D. was due to a comet or asteroid hitting the Earth, it is widely thought that the event was probably caused by the most massive volcanic eruption of the past 1500 years. This eruption threw so much sulfur dioxide (SO2) gas into the stratosphere that a "Volcanic Winter" resulted. Sulfur dioxide reacts with water to form sulfuric acid droplets (aerosol particles), which are highly reflective and reduce the amount of incoming sunlight. The potential eruption that led to the 535 - 536 A.D. climate calamity would have likely been a magnitude 7 event on the Volcanic Explosivity Index (VEI)--a "super colossal" eruption that one can expect to occur only once every 1000 years. The Volcanic Explosivity Index is a logarithmic scale like the Richter scale used to rate earthquakes, so a magnitude 7 eruption would eject ten times more material than the two largest eruptions of the past century--the magnitude 6 eruptions of Mt. Pinatubo in the Philippines (1991) and Novarupta in Alaska (1912).


Figure 1. An 18 km-high volcanic plume from one of a series of explosive eruptions of Mount Pinatubo beginning on 12 June 1991, viewed from Clark Air Base (about 20 km east of the volcano). Three days later, the most powerful eruption produced a plume that rose nearly 40 km, penetrating well into the stratosphere. Pinatubo's sulfur emissions cooled the Earth by about 1°F (0.5°C) for 1 - 2 years. (Photograph by David H. Harlow, USGS.)

Super-colossal eruptions
There has been only one other magnitude 7 "super-colossal" eruption in the past 1500 years--the massive eruption of the Indonesian volcano Tambora in 1815. The sulfur pumped by this eruption into the stratosphere dimmed sunlight so extensively that global temperatures fell by about 2°F (1°C) for 1 - 2 years afterward. This triggered the famed Year Without a Summer in 1816. Killing frosts and snow storms in May and June 1816 in Eastern Canada and New England caused widespread crop failures, and lake and river ice were observed as far south as Pennsylvania in July and August. The Tambora eruption was about 40% smaller than the 535 - 536 A.D. event, as measured by the number of sulfur aerosol particles deposited in Greenland ice cores.

In an article published in 2008 in the American Geophysical Union journal EOS, Dr. Ken Verosub of the University of California, Davis Department of Geology estimated that future eruptions capable of causing "Volcanic Winter" effects severe enough to depress global temperatures by 2°F (1°C) and trigger widespread crop failures for 1 - 2 years afterwards should occur about once every 200 - 300 years. Even a magnitude 6 eruption, such as the 1600 eruption of the Peruvian volcano Huaynaputina, can cause climatic change capable of killing millions of people. The Huaynaputina eruption is blamed for the Russian famine of 1601-1603, which killed over half a million people and led to the overthrow of Tsar Boris Godunov. Thankfully, the climatic impacts of all of these historic magnitude 6 and 7 eruptions have been relatively short-lived. After about two years, the sulfuric acid aerosol particles have settled out of the stratosphere, returning the climate to its former state.

Mega-colossal eruptions
Even more extreme eruptions have occurred in Earth's past--eruptions ten times more powerful than the Tambora eruption, earning a ranking of 8 out of 8 on the Volcanic Explosivity Index (VEI). These "mega-colossal" eruptions occur only about once every 10,000 years, but have much longer-lasting climatic effects and thus are a more significant threat to human civilization. According to the Toba Catastrophe Theory, a mega-colossal eruption at Toba Caldera, Sumatra, about 74,000 years ago, was 3500 times greater than the Tambora eruption. According to model simulations, an eruption this large can pump so much sulfur dioxide gas into the stratosphere that the atmosphere does not have the capacity to oxidize all the SO2 to sulfuric acid aerosol. The atmosphere oxidizes as much SO2 as it can, leaving a huge reservoir of SO2 in the stratosphere. This SO2 gradually reacts to form sulfuric acid as the OH radicals needed for this reaction are gradually produced. The result is a much longer-lasting climate effect than the 1 - 2 years that the magnitude 6 and 7 events of 535, 1600, 1815, and 1991 lasted. A magnitude 8 eruption like the Toba event can cool the globe for 6 - 10 years (Figure 3), which may be long enough to trigger an ice age--if the climate is already on the verge of tipping into an ice age. Rampino and Self (1992) argued that the sulfur aerosol veil from Toba was thick and long-lasting enough to cool the globe by 3 - 5°C (5 - 9°F), pushing the climate--which was already cooling and perhaps headed towards an ice age--into a full-scale ice age. They suggested that the response of Canada to the volcano played a particularly important role, with their model predicting a 12°C (22°F) reduction in summer temperatures in Canada. This would have favored the growth of the Laurentide ice sheet, increasing the reflectivity (albedo) of the Earth, reflecting more sunlight and reducing temperatures further. The controversial Toba Catastrophe Theory asserts that the resulting sudden climate change reduced the Earth's population of humans to 1,000 - 10,000 breeding pairs. More recent research has shed considerable doubt on the idea that the Toba eruption pushed the climate into an ice age, though. Oppenheimer (2002) found evidence supporting only a 2°F (1.1°C) cooling of the globe, for the 1000 years after the Toba eruption. Zielinski et al. (1996) argued that the Toba eruption did not trigger a major ice age--the eruption merely pushed the globe into a cool period that lasted 200 years. Interestingly, a previous super-eruption of Toba, 788,000 years ago, coincided with a transition from an ice age to a warm period.


Figure 2. The 100x30 square kilometer Toba Caldera is situated in north-central Sumatra around 200 km north of the Equator. It is comprised of four overlapping calderas aligned with the Sumatran volcanic chain. Repeated volcanic cataclysms culminated in the stupendous expulsion of the Younger Toba Tuff around 74,000 years ago. The lake area is 100 square kilometers. Samosir Island formed as a result of subsequent uplift above the evacuated magma reservoir. Such resurgent domes are typically seen as the concluding phase of a large eruption. Landsat Enhanced Thematic Mapper Plus (ETM+) browse images for path/row 128/58 (6 September 1999) and 129/58 (21 January 2001) from http://landsat7.usgs.gov/. Copyright USGS. Image source: Oppenheimer, C., 2002, "Limited global change due to the largest known Quaternary eruption, Toba 74 kyr BP?"Quaternary Science Reviews, 21, Issues 14-15, August 2002, Pages 1593-1609.


Figure 3. Total mass of sulfur dioxide and sulfate aerosol in the stratosphere (heavy solid and dotted lines, respectively) modeled for a 6 petagram stratospheric injection of SO2. Observed SO2 and aerosol mass for the 1991 Pinatubo eruption are shown for comparison. The much larger amount of SO2 in the Toba simulation soaks up all available oxidants in the stratosphere leading to a much longer lifetime of SO2 and, in turn, prolonging the manufacture of sulfate aerosol. Data from Read et al. (1993) and Bekki et al. (1996). Image source: Oppenheimer, C., 2002, "Limited global change due to the largest known Quaternary eruption, Toba 74 kyr BP?"Quaternary Science Reviews, 21, Issues 14-15, August 2002, Pages 1593-1609.

When can we expect the next mega-colossal eruption?
Given the observed frequency of one mega-colossal magnitude 8 volcanic eruption every 1.4 million years, the odds of another hitting in the next 100 years is about .014%, according to Mason et al., 2004. This works out to a 1% chance over the next 7200 years. Rampino (2002) puts the average frequency of such eruptions at once every 50,000 years--about double the frequency with which 1-km diameter comets or asteroids capable of causing a similar climatic effect hit the Earth. A likely location for the next mega-colossal eruption would be at the Yellowstone Caldera in Wyoming, which has had magnitude 7 or 8 eruptions as often as every 650,000 years. The last mega-colossal eruption there was about 640,000 years ago. But don't worry, the seismic activity under Yellowstone Lake earlier this year has died down, and the uplift of the ground over the Yellowstone caldera that was as large as 7 cm/yr (2.7 inches/yr) between 2004 - 2006 has now fallen to 4 cm/yr, according to the Yellowstone Volcano Observatory. The USGS states that "the Yellowstone volcanic system shows no signs that it is headed toward such an eruption. The probability of a large caldera-forming eruption within the next few thousand years is exceedingly low".

What would happen if a magnitude 8 mega-colossal eruption were to occur today?
If a mega-colossal eruption were to occur today, it would probably not be able to push Earth into an ice age, according to a modeling study done by Jones et al. (2005). They found that an eruption like Toba would cool the Earth by about 17°F (9.4°C) after the first year (Figure 3), and the temperature would gradually recover to 3°F (1.8°C) below normal ten years after the eruption. They found that the eruption would reduce rainfall by 50% globally for the first two years, and up to 90% over the Amazon, Southeast Asia, and central Africa. This would obviously be very bad for human civilization, with the cold and lack of sunshine causing widespread crop failures and starvation of millions of people. Furthermore, the eruption would lead to a partial loss of Earth's protective ozone layer, allowing highly damaging levels of ultraviolet light to penetrate to the surface.

Not even a mega-colossal eruption of this magnitude would stop global warming, though. The level of greenhouse gases in the atmosphere would not be affected by the volcanic eruption, and warming would resume where it left off once the stratospheric dust settled out in a decade. With civilization crippled by the disaster, greenhouse gas emissions would be substantially reduced, though (small solace!) If we really want to say goodbye to civilization, a repeat of the only magnitude 9 eruption in recorded history should do the trick--the magnitude 9.2 La Garita, Colorado blast of 27.8 million years ago (Mason et al., 2004).


Figure 4. Annual near-surface temperature anomalies for the year following a mega-colossal volcanic eruption like the Toba eruption of 74,000 years ago, if it were to occur today. Most land areas cool by 22°F (12°C) compared to average. Some areas, like Africa, cool by 29°F (16°C). Image credit: Jones, G.S., et al., 2005, "An AOGCM simulation of the climate response to a volcanic super-eruption", Climate Dynamics, 25, Numbers 7-8, pp 725-738, December, 2005.

What would happen if a magnitude 7 super-colossal eruption were to occur today?
An eruption today like the magnitude 7 events of 535 A.D. or 1815 would cause cause wide-spread crop failures for 1 - 2 years after the eruption. With food supplies in the world already stretched thin by rising population, decreased water availability, and conversion of cropland to grow biofuels, a major volcanic eruption would probably create widespread famine, threatening the lives of millions of people. Wars over scarce resources might result. However, society's vulnerability to major volcanic eruptions is less than it was, since the globe has warmed significantly in the past 200 years. The famines from the eruptions of 1600 and 1815 both occurred during the Little Ice Age, when global temperatures were about 1.4°F (0.8°C) cooler than today. Crop failures would not be as wide-spread with today's global temperatures, if a suer-colossal eruption were to occur. Fifty years from now, when global temperatures are expected to be at least 1°C warmer, a magnitude 7 eruption should only be able to cool the climate down to year 2009 levels.

Volcanoes also warm the climate
While volcanoes cool the climate on time scales of 1 - 2 years, they act to warm the climate over longer time scales, since they are an important source of natural CO2 to the atmosphere. Volcanoes add 0.1 - 0.3 gigatons (Gt) of carbon to the atmosphere each year, which is about 1 - 3% of what human carbon emissions to the atmosphere were in 2007, according to the Global Carbon Project. In fact, volcanoes are largely responsible for the natural CO2 in the atmosphere, and helped make life possible on Earth. Why, then, haven't CO2 levels continuously risen over geologic time, turning Earth into a steamy hothouse? In fact, CO2 levels have fallen considerably since the time of the dinosaurs--how can this be? Well, volcano-emitted CO2 is removed from the atmosphere by chemical weathering. This occurs when rain and snow fall on rocks containing silicates. The moisture and silicates react with CO2, pulling it out of the air. The carbon removed from the air is then washed into the sea, where it ends up in ocean sediments that gradually harden into rock. Rates of chemical weathering on Earth have accelerated since the time of the dinosaurs, largely due to the recent uplift of the Himalaya Mountains and Tibetan Plateau. These highlands undergo a tremendous amount of weathering, thanks to their lofty heights and the rains of the Asian Monsoon that they capture. Unfortunately, chemical weathering cannot help us with our current high levels of greenhouse gases, since chemical weathering takes thousands of years to remove significant amounts of CO2 from the atmosphere. It takes about 100,000 years for silicate weathering to remove 63% of the CO2 in the atmosphere. Thus, climate models predict that chemical weathering will solve our greenhouse gas problem in about 100,000 - 200,000 years.

For further information
PBS TV special on the 535-536 A.D. disaster.
Newspaper articles on the 535-536 A.D. disaster.
Volcanic winter article from wikipedia.
Realclimate.org has a nice article that goes into the volcano-climate connection in greater detail.

References
Bekki, S., J.A. Pyle, W. Zhong, R. Toumi, J.D. Haigh and D.M. Pyle, 1996, "The role of microphysical and chemical processes in prolonging the climate forcing of the Toba eruption", Geophysical Research Letters 23 (1996), pp. 2669-2672.

Jones, G.S., et al., 2005, "An AOGCM simulation of the climate response to a volcanic super-eruption", Climate Dynamics, 25, Numbers 7-8, pp 725-738, December, 2005.

Rampino, M.R., and S. Self, 1993, "Climate-volcanism feedback and the Toba eruption of 74,000 years ago", Quaternary Research 40 (1993), pp. 269-280.

Mason, B.G., D.M. Pyle, and C. Oppenheimer, 2004, "The size and frequency of the largest observed explosive eruptions on Earth", Bulletin of Volcanology" 66, Number 8, December 2004, pp 735-748.

Oppenheimer, C., 2002, "Limited global change due to the largest known Quaternary eruption, Toba 74 kyr BP?"Quaternary Science Reviews, 21, Issues 14-15, August 2002, Pages 1593-1609.

Rampino, M.R., 2002, "Supereruptions as a Threat to Civilizations on Earth-like Planets", Icarus, 156, Issue 2, April 2002, Pages 562-569.

Read, W.G., L. Froidevaux and J.W. Waters, 1993, "Microwave Limb Sounder measurements of stratospheric SO2 from the Mt. Pinatubo eruption", Geophysical Research Letters 20 (1993), pp. 1299-1302.

Verosub, K.L., and J. Lippman, 2008, "Global Impacts of the 1600 Eruption of Peru's Huaynaputina Volcano", EOS 89, 15, 8 April 2008, pp 141-142.

Zielinski, G.A. et al., 1996, "Potential Atmospheric Impact of the Toba Mega-Eruption 71,000 Years Ago", Geophysical Research Letters, 23, 8, pp. 837-840, 1996.

Portlight moves to provide relief for South Carolina wildfires
South Carolina's biggest wildfire in more than three decades --a blaze four miles wide--destroyed dozens of homes near Myrtle Beach yesterday. Portlight Strategies, Inc. is preparing to respond to this disaster, focusing on providing drinks and sanitary products to firefighters, particularly to rural volunteer fire departments and other first responders which do not have the same resources as some of the larger paid departments. To help out, visit the Portlight South Carolina fire relief web page. Thanks!

Jeff Masters

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1634. Ossqss
Quoting SevereHurricane:


I received some really nice messages too...


I feel slighted, I did not get a single one
Member Since: June 12, 2005 Posts: 6 Comments: 8188
Quoting Stormchaser2007:


You should have seen the messages he sent me....


I received some really nice messages too...
Member Since: September 7, 2008 Posts: 17 Comments: 1604
Quoting CaneAddict:


Thanks for asking, I am doing great but starting to prepare for the season..are you prepared yet?


I'm prepared. :D
But you can only be so prepared when you are below sea level...
Member Since: September 7, 2008 Posts: 17 Comments: 1604
Quoting weatherblog:
I'm just wondering, why everyone was so harsh to JFV? Was it because he made another handle? I bet a lot of you have made another one before.

Not that it really matters, but a lot of you didn't need to be so rude to him.


You should have seen the messages he sent me....
Member Since: June 9, 2007 Posts: 4 Comments: 15950
Quoting CaneAddict:


I understand where your coming from in his defense but it was way more than his handle being changed...He emailed me and a few others I know of very rude emails just because we told him to stop asking the same questions over and over...and he's constantly over-hyping the tropics...He would not stop repeating his self in the blog and it quite honestly was getting annoying.


All of what CaneAddict said
Not to mention he was causeing drama and being rude to others on the blog.I was getting tired of it.Its not even May folks and we had that going on!
Member Since: September 7, 2008 Posts: 17 Comments: 1604
Quoting CaneAddict:


I understand where your coming from in his defense but it was way more than his handle being changed...He emailed me and a few others I know of very rude emails just because we told him to stop asking the same questions over and over...and he's constantly over-hyping the tropics...He would not stop repeating his self in the blog and it quite honestly was getting annoying.


OK, I did not know he sent out rude emails. I guess that changes the situation. From what I know, he was always very nice to me.
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Quoting SevereHurricane:


I'm fantastic!
I'm just glad the blog is drama free again,
at least for now.
But I just can't believe we had all that going on and its not even May yet!
I'm scared to think about how bad it will be in the Heat of Hurricane Season.
I certainly hope it won't be as bad as last year...

How are you doing?


Thanks for asking, I am doing great but starting to prepare for the season..are you prepared yet?
Member Since: October 5, 2007 Posts: 3 Comments: 2151
1626. hahaguy
Quoting futuremet:


This year is quite exceptional, dried out lakes are too ubiquitous here in central FL


Actually PSL is considered South Florida. The whole Treasure Coast is.
Member Since: August 12, 2007 Posts: 2 Comments: 2838
Quoting weatherblog:
I'm just wondering, why everyone was so harsh to JFV? Was it because he made another handle? I bet a lot of you have made another one before.

Not that it really matters, but a lot of you didn't need to be so rude to him.


I understand where your coming from in his defense but it was way more than his handle being changed...He emailed me and a few others I know of very rude emails just because we told him to stop asking the same questions over and over...and he's constantly over-hyping the tropics...He would not stop repeating his self in the blog and it quite honestly was getting annoying.
Member Since: October 5, 2007 Posts: 3 Comments: 2151
1624. Drakoen
Quoting weatherblog:
I'm just wondering, why everyone was so harsh to JFV? Was it because he made another handle? I bet a lot of you have made another one before.

Not that it really matters, but a lot of you didn't need to be so rude to him.


You don't know what he has done to others.
Member Since: Posts: Comments:
I'm just wondering, why everyone was so harsh to JFV? Was it because he made another handle? I bet a lot of you have made another one before.

Not that it really matters, but a lot of you didn't need to be so rude to him.
Member Since: Posts: Comments:
Quoting GeoffreyWPB:
I think we live in the same general area future...hopefully the pattern will change soon where the sea breeze afternoon t-storms (which can and have dumped a lot of rain on us in past seasons) will return soon and not leave us the option of having to suffer through a Hurricane. A T.S. like Fay (as it affected Palm Beach County and Lake O.), I can handle.


This year is quite exceptional, dried out lakes are too ubiquitous here in central FL
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Thanks EXPRESS
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Quoting CaneAddict:


your welcome..How are ya?


I'm fantastic!
I'm just glad the blog is drama free again,
at least for now.
But I just can't believe we had all that going on and its not even May yet!
I'm scared to think about how bad it will be in the Heat of Hurricane Season.
I certainly hope it won't be as bad as last year...

How are you doing?
Member Since: September 7, 2008 Posts: 17 Comments: 1604
1618. Ossqss
Found one finallyLink
Member Since: June 12, 2005 Posts: 6 Comments: 8188
Quoting hurricane23:
SOI now up to +10.3 but looking for a drop coming up fairly soon- probably to open May. Still, we are now well above zero on the SOI so no El Nino anytime soon- that is almost certain in my view.


Do you still go to FSU Adrian?
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SOI now up to 10.3 but looking for a drop coming up fairly soon,probably to open May. Still, we are now well above zero on the SOI so no El Nino anytime soon- that is almost certain in my view.
Member Since: May 14, 2006 Posts: 8 Comments: 13841
Quoting Ossqss:


Do you have a link Futuremet?


No, I memorized it, the track shifted slightly southward from the previous day. This system is having a hard time sustaining its cyclonic spin due to the lack of Corf. This system is located near 6S, and latitude below 5s or 5n are unfavorable for tropical cyclogenesis.
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I think we live in the same general area future...hopefully the pattern will change soon where the sea breeze afternoon t-storms (which can and have dumped a lot of rain on us in past seasons) will return soon and not leave us the option of having to suffer through a Hurricane. A T.S. like Fay (as it affected Palm Beach County and Lake O.), I can handle.
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it was sunny out and here came some vary big winds not sure how strong the wind where but they where so strong that it pick up drit in too the air so i would say winds where 80 to 100mph winds
Member Since: May 21, 2006 Posts: 5091 Comments: 115456
Nothing on the ECMWF....

Incredible footage but this is just to damn close for me.

Member Since: May 14, 2006 Posts: 8 Comments: 13841
1611. Ossqss
Quoting futuremet:
Wow, the equator is just invincible, Kirrikily could not move farther northward. The track has shifted slightly south.


Do you have a link Futuremet?
Member Since: June 12, 2005 Posts: 6 Comments: 8188
cool pat
Member Since: May 21, 2006 Posts: 5091 Comments: 115456
Wow, the equator is just invincible, Kirrikily could not move farther northward. The track has shifted slightly south.
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Quoting GeoffreyWPB:
I agree future...but right now, there is no there,…there and the odds that the gfs scenario will pan out are almost nil.


I agree, I highly out this forecast

I am just pointing the 'if' scenario
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yes it is pat




angle camp CA had one a vary long time a go to win i was vary little
Member Since: May 21, 2006 Posts: 5091 Comments: 115456
I agree future...but right now, there is no there,…there and the odds that the gfs scenario will pan out are almost nil.
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Quoting SevereHurricane:


hmmmm,
Thanks.


your welcome..How are ya?
Member Since: October 5, 2007 Posts: 3 Comments: 2151
1604. Patrap
Thats a rare event for Cali Taz..cool.

Check out this one from Iowa Taz.

Video from TornadoVideos.net Stream Team #3 of a strong gustnado crossing the road only 100 yards away on June 7, 2008 in central Iowa! This supercell had a tornado warning for some time, but produced only gustnadoes and rapidly rotating wall clouds.


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PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE SACRAMENTO CA
720 PM PDT SAT APR 25 2009

...PUBLIC INFORMATION STATEMENT CONCERNING WIND DAMAGE IN
WOODLAND CALIFORNIA ON APRIL 24 2009...

ON FRIDAY...APRIL 24 2009...STRONG WINDS CAUSED RELATIVELY MINOR
DAMAGE IN WOODLAND CA...ABOUT 18 MILES NORTHWEST OF DOWNTOWN
SACRAMENTO CA. PRELIMINARY FINDINGS FROM A DAMAGE SURVEY PERFORMED
BY NATIONAL WEATHER SERVICE FORECASTERS FROM SACRAMENTO CA
INDICATED THE WIND DAMAGE WAS NOT FROM A TORNADO...BUT FROM A
GUSTNADO.

A GUSTNADO IS A SHORT-LIVED...GROUND BASED SHALLOW VORTEX...THAT
DEVELOPS ALONG A GUST FRONT OR BOUNDARY ASSOCIATED WITH EITHER
THUNDERSTORMS OR SHOWERS. IT MAY EXTEND 30 TO 300 FEET ABOVE THE
GROUND BUT IS NOT CONNECTED TO THE BASE OF A CLOUD. GUSTNADOES ARE
USUALLY ONLY VISIBLE AS A DEBRIS CLOUD OR DUST WHIRL NEAR THE
GROUND. WIND SPEEDS CAN REACH 60 TO 80 MPH AND CAN CAUSE WIND
DAMAGE SIMILAR TO WEAK TORNADOES. GUSTNADOES ARE NOT ASSOCIATED
WITH STORM SCALE ROTATION THAT IS TRUE WITH TORNADOES.

SHORTLY BEFORE 5 PM LOCAL TIME...WITNESSES STATED THAT THEY SAW A
SWIRLING DEBRIS CLOUD MOVING WEST TO EAST ACROSS THE YOLO COUNTY
FAIRGROUNDS TOWARDS THE LEISUREVILLE MOBILE HOME PARK. THE GUSTNADO
INITIALLY UPROOTED A TREE ABOUT 18 INCHES TO 2 FEET IN DIAMETER
ALONG EAST ST...ON THE WEST SIDE OF THE FAIRGROUNDS...THEN UPLIFTED
A SECTION OF METAL BLEACHERS IN THE STADIUM...DAMAGED A COUPLE OF
TENTS SET UP FOR A FESTIVAL...AND DID RELATIVELY MINOR PROPERTY
DAMAGE TO 3 MOBILE HOME TRAILERS ON DUAL WIDE ROAD IN THE MOBILE
HOME PARK. THE DAMAGE PATH WAS DISCONTINUOUS OVER 3 BLOCKS LONG
AND ABOUT 20 FEET ACROSS. ACCORDING TO WITNESSES...THE DEBRIS
CLOUD LASTED ONLY A FEW MINUTES. RAIN...THUNDER AND LIGHTNING WERE
NOT OCCURRING DURING THIS TIME.

DOPPLER RADAR INDICATED LIGHT SHOWERS DEVELOPING IN THE WOODLAND
AREA DURING THIS TIME. HOWEVER...A STRONG UPPER LEVEL LOW
PRESSURE SYSTEM WAS MOVING IN FROM THE NORTH AND WAS INTERACTING
WITH A MODERATELY STRONG DELTA BREEZE WITH GUSTY SOUTHWEST WINDS
20 TO 25 MPH. ABOUT 30 MINUTES AFTER THE GUSTNADO...A LINE OF
SHOWERS AND ISOLATED THUNDERSTORMS DID FORM SOUTHEAST OF THE
WOODLAND AREA. WEATHER OBSERVATIONS FROM THE YOLO COUNTY AIRPORT
INDICATED THE SOUTHWEST WINDS SHIFTED FROM THE NORTHWEST AT 609
PM.

BASED ON THE WEAK RADAR RETURNS PRIOR TO 5 PM...THE GUSTY SOUTHWEST
WINDS FROM THE DELTA BREEZE...AND THE AFFECTS OF THE STRONG UPPER
LEVEL LOW PRESSURE SYSTEM MOVING INTO THE AREA...IT IS BELIEVED
THE GUSTNADO FORMED ON A WIND SHIFT BOUNDARY AHEAD OF...OR ASSOCIATED
WITH...A DEVELOPING LINE OF SHOWERS.

BASED ON DAMAGE AT THE LOCATION...NATIONAL WEATHER SERVICE
FORECASTERS ESTIMATED THE PEAK WIND SPEEDS TO HAVE REACHED UP TO
70 MPH TO 75 MPH.
Member Since: May 21, 2006 Posts: 5091 Comments: 115456
Quoting Patrap:
..its definitely trending WEST.


I actually want this system to hit Florida, due to the severe drought. This system, if it does develop and hit land, will not be wind threat. Excessive wind shear caused by the STJ should substantially decouple the windfield and make it asymmetric. You can clear see this in the 18z run as it curves northeastward.
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actually a little rain right now in lake worth..and pretty windy also
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Quoting CaneAddict:


He probably finally got permanently banned by IP Address. He circumvented the ban with making a new user handle and continued to email folks with rude emails.


hmmmm,
Thanks.
Member Since: September 7, 2008 Posts: 17 Comments: 1604
1599. Patrap
..its definitely trending WEST.
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1598. JRRP
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Hey TS.. it's just about time for that closet again. :(
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Quoting SevereHurricane:
Where did PE go?


He probably finally got permanently banned by IP Address. He circumvented the ban with making a new user handle and continued to email folks with rude emails.
Member Since: October 5, 2007 Posts: 3 Comments: 2151
I love reading the archives....last year, this week...the chat was about TC Nargis, Dr. Grey's 2008 predictions, gas prices and.......the GFS forecasting a storm in the GOM in early May!
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Just wondering who would think it is a good idea to go sit in a hospital emergency room, 'cause they have flu symptoms. If there is a flu epidemic, the ER is the LAST place I would hang out.

If you are going to wear a mask, it is more effective if you wear it over both your mouth AND your NOSE.

If you are going to the bother of wearing a mask, don't sneak under it to rub your nose. And keep your hands away from your eyes.

One more thing, if you are coughing, now is not the time to go shopping!
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Quoting moonlightcowboy:
Evening, all. I was wondering if our phantom storm had achieved CAT 5 status yet. Any updates? ;P Is it gonna hit FL? Or NOLA? LOL

Y'all have fun! Play nice!


The GFS has it hitting South Florida. lol
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Wow, 18z GFS takes that Carib storm, tracks it into the gulf, then explodes it as an extratropical storm over Southern Ontario.
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Where did PE go?
Member Since: September 7, 2008 Posts: 17 Comments: 1604
1590. Ossqss
Just got an email relating to immune system over response, like SARS , could be a culprit in the mix on the young death rates. I guess time will tell all truths.
Member Since: June 12, 2005 Posts: 6 Comments: 8188
Quoting TampaSpin:
Someone said they would not worry until death.

MEXICO Baja California Norte
Last Updated by niman 3 days ago

24/04/2009 Two fatalities
Thirteen fatal cases of severe respiratory illness were reported in Mexico City; four in San Luis Potosi, a city north of the capital; two in the state of Baja California Norte, bordering California; and another in Oaxaca city in the south.


Those were just bordering California - not in California.
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Someone said they would not worry until death.

MEXICO Baja California Norte
Last Updated by niman 3 days ago

24/04/2009 Two fatalities
Thirteen fatal cases of severe respiratory illness were reported in Mexico City; four in San Luis Potosi, a city north of the capital; two in the state of Baja California Norte, bordering California; and another in Oaxaca city in the south.
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Quoting CybrTeddy:
I can't help to wonder,
If this gets too bad would they close jobs and schools throughout the country?


It's possible, but in my opinion it would have to be much worse.
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I can't help to wonder,
If this gets too bad would they close jobs and schools throughout the country?
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1584. hahaguy
Quoting TampaSpin:


Hey thats a thought! Selling man purses with a little Alcohol included.....LOL


Like on Seinfeld, a European Men's carryall. LOL
Member Since: August 12, 2007 Posts: 2 Comments: 2838

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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

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