World Weather News

October 20th 2020

NOAA – La Niña cooling flip has occurred

‘The Northern Hemisphere winter of 2020/21 is shaping up to be a doozy,” says reader Martin Siebert.

The latest CFSv2** forecast for region 3.4 of the central equatorial Pacific Ocean reveals that a flip from the recent El Niño setup (warming) to a La Niña one (cooling) has occurred.

CFSV2 FORECASTS LA NIÑA (COOLING) INTO 2021

La Niña’s are usually associated with cooler global average temperatures, droughts in the southern U.S., and anomalously wet conditions in Australia.



The latest CFSv2 forecast for region 3.4 of the central equatorial Pacific Ocean reveals that a flip from the recent El Niño setup (warming) to a La Niña one (cooling) has occurred.

The below chart shows Sea Surface Temperatures (SSTs) for region 3.4. of the equatorial Pacific: that black-dash line has dipped deep into La Niña territory, and the model sees this persisting through the remainder of 2020 and into 2021:


October 15th 2020


For Comparison




October 10th 2020:

Louisiana has now had four named storm landfalls in 2020 (Cristobal, Laura, Marco and #Delta). 2020 is now tied with 2002 for the most Louisiana named storm landfalls in a single season on record. In 2002, Bertha, Hanna, Isidore and Lili made landfall in Louisiana.
The most recent October Louisiana #hurricane landfalls by Saffir-Simpson category are: Category 1: Nate (2017) Category 2: Hilda (1964) Category 3: Texas-Louisiana Hurricane (1886) Category 4: Chenier Caminanda (1893) Category 5: None on record
Delta is the 10th named storm to make landfall in the continental US this year - the most in a single Atlantic hurricane season on record. Prior to 2020, the most named storms to make landfall in the continental US was 9 set in 1916
Info by Vagarian Vineet Kumar (IITM )
September 28th 2020:
Coldest Northern Hemisphere temperature, first recorded by UW, officially confirmed

UNIVERSITY OF WISCONSIN-MADISON

Research News

MADISON, Wis. — Nearly 30 years after recording a temperature of minus 93.2 degrees Fahrenheit (minus 69.6 Celsius) in Greenland, the measurement has been verified by the World Meteorological Organization as the coldest recorded temperature in the Northern Hemisphere.

The measurement was first recorded by a University of Wisconsin-Madison Antarctic Meteorological Research Center Automatic Weather Station in December 1991. An AWS is a standalone instrument suite developed by UW-Madison Space Science and Engineering Center and AMRC scientists and engineers to collect numerous environmental parameters such as air temperature, pressure, humidity, wind direction and speed. The information is then relayed via satellite back to SSEC in near real time.

Extreme measurements like that in Greenland undergo a rigorous review process to make sure they are accurate and there is agreement with other meteorological data and weather forecast models. Due to the quality and preservation of the AWS station data provided by the Antarctic Meteorological Research Center, the WMO was able to verify the 1991 temperature and log it as part of the official record.

According to Weidner, this cold temperature was the result of several atmospheric conditions converging in a specific way.

The Klinck field site, where the coldest temperature was measured, is located in the middle of Greenland at an elevation of 10,170 feet (3,100 meters). Extreme cold air temperatures can occur when there is little wind to disturb an area, accompanied by clear skies.

In this case, the elevation and a splitting of the jet stream — which usually flows over the Greenland ice sheet — created a dead zone, allowing the already cold region to continue losing heat from the Earth. Similar conditions occur over Canada and result in the famed (or infamous) “polar vortex,” which produces extreme cold that reaches the U.S.

September 24th 2020

Big Chill...U.K. to be Battered by Torrential Rains and Gales...Temperatures to Plunge...Artic Blast to Hit U.K.

blob:https://www.thesun.co.uk/c05908fc-f381-4708-8284-9ca4e2258e35


September 22nd 2020

Beta storm made landfall in US, this is the 9th named storm to make landfall in Continental US this season. This equals the record of 1916 of most continental US landfalls

September 17th 2020:

We have talking a lot of the fires in U.S. ...The Fact of Fire History.

Irrefutable NASA data: global fires down by 25 percent

Using satellite technology, NASA determined that between 2003 and 2019, global fires have dropped by roughly 25 percentThis makes the “climate change is worsening wildfires” argument completely moot.

From NASA Earth Observatory

The control of fire is a goal that may well be as old as humanity, but the systematic monitoring of fire on a global scale is a much newer capability.

In the 1910s, the U.S. Forest Service began building fire lookout towers on mountain peaks in order to detect distant fires. A few decades later, fire-spotting airplanes flew onto the scene. Then in the early 1980s, satellites began to map fires over large areas from the vantage point of space.

Over time, researchers have built a rich and textured record of Earth’s fire activity and are now able to analyze decadal trends. “The pace of discovery has increased dramatically during the satellite era,” said James Randerson, a scientist at the University of California, Irvine. “Having high-quality, daily observations of fires available on a global scale has been critical.”

The animation above shows the locations of actively burning fires on a monthly basis for nearly two decades. The maps are based on observations from the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite. The colors are based on a count of the number (not size) of fires observed within a 1,000-square-kilometer area. White pixels show the high end of the count—as many as 30 fires in a 1,000-square-kilometer area per day. Orange pixels show as many as 10 fires, while red areas show as few as 1 fire per day.

December 1, 2014 – August 31, 2015

The sequence highlights the rhythms—both natural and human-caused—in global fire activity. Bands of fire sweep across Eurasia, North America, and Southeast Asia as farmers clear and maintain fields in April and May. Summer brings new activity in boreal and temperate forests in North America and Eurasia due to lighting-triggered fires burning in remote areas. In the tropical forests of South America and equatorial Asia, fires flare up in August, September, and October as people make use of the dry season to clear rainforest and savanna, as well as stop trees and shrubs from encroaching on already cleared land. Few months pass in Australia without large numbers of fires burning somewhere on the continent’s vast grasslands, savannas, and tropical forests.

But it is Africa that is truly the fire continent. On an average day in August, the Moderate Resolution Imaging Spectroradiometers (MODIS) on NASA’s Aqua and Terra satellites detect 10,000 actively burning fires around the world—and 70 percent them happen in Africa. Huge numbers of blazes spring up in the northern part of continent in December and January. A half year later, the burning has shifted south. Indeed, global fire emissions typically peak in August and September, coinciding with the main fire seasons of the Southern Hemisphere, particularly Africa. (High activity in temperate and boreal forests in the Northern Hemisphere in the summer also contribute.)

August 29, 2018

The second animation underscores how much fire activity shifts seasonally by highlighting burning activity during December 2014, April 2015, and August 2015. The satellite image above shows smoke rising from the savanna of northern Zambia on August 29, 2018, around the time global emissions reach their maximum.

Though Africa dominates in the sheer number of fires, fires seasons there are pretty consistent from year-to-year. The most variable fire seasons happen elsewhere, such as the tropical forests of South America and equatorial Asia. In these areas, the severity of fire season is often linked to cycles of El Niño and La Niña. The buildup of warm water in the eastern Pacific during an El Niño changes atmospheric patterns and reduces rainfall over many rainforests, allowing them to burn more easily and widely.https://www.youtube.com/embed/69N494UIlS8?flag=1&enablejsapi=1&html5=1&origin=https://earthobservatory.nasa.gov

Despite the vast quantities of carbon released by fires in savannas, grasslands, and boreal forests, research shows that fires in these biomes do not generally add carbon to the atmosphere in the long term. The regrowth of vegetation or the creation of charcoal typically recaptures all of the carbon within months or years. However, when fires permanently remove trees or burn through peat (a carbon-rich fuel that can take centuries to form), little carbon is recaptured and the atmosphere sees a net increase in CO2.

That is why outbreaks of fire in countries with large amounts of peat, such as Indonesia, have an outsized effect on global climate. Fires in equatorial Asia account for just 0.6 percent of global burned area, yet the region accounts for 8 percent of carbon emissions and 23 percent of methane emissions. On October, 25, 2015, the Earth Polychromatic Imaging Camera aboard the DSCOVR satellite acquired an image (below) of heavy smoke over Indonesia; El Niño was particularly active at the time.

October 15, 2015

One of the most interesting things researchers have discovered since MODIS began collecting measurements, noted Randerson, is a decrease in the total number of square kilometers burned each year. Between 2003 and 2019, that number has dropped by roughly 25 percent.

As populations have increased in fire-prone regions of Africa, South America, and Central Asia, grasslands and savannas have become more developed and converted into farmland. As a result, long-standing habits of burning grasslands (to clear shrubs and land for cattle or other reasons) have decreased, explained NASA Goddard Space Flight scientist Niels Andela. And instead of using fire, people increasingly use machines to clear crops.

“There are really two separate trends,” said Randerson. “Even as the global burned area number has declined because of what is happening in savannas, we are seeing a significant increase in the intensity and reach of fires in the western United States because of climate change.”

2003 – 2015

When researchers began using satellites to study the world’s fires in the 1980s, they were just sorting out the basics of how to detect fires from space. Now after mining MODIS data for nearly two decades, scientists are looking ahead to other satellites and technologies that they hope will advance the study of fire in the coming years.

A series of follow-on sensors called the Visible Infrared Imaging Radiometer Suite (VIIRS) on the Suomi NPP and NOAA-20 satellites now make near-real time observations of emissions that are even more accurate than those from MODIS because of improved fire detections along the edge of the edges of images, noted Andela.

Meanwhile, the launch of satellites with higher-resolution sensors is also helping. “The Landsat 8 and Sentinel satellites, in particular, are contributing to a revolution in our ability to measure the burned area of small grassland and forest fires,” said Randerson. “And we are going to need additional detection capabilities in the coming years to track increasingly destructive mega fires during all times of day and night.”


September 12th 2020; 
see the fall in Max temperature at Denver in 2 days !38c to 13c  !



September 4th:

First super typhoon of the year has formed in NW pacific. Name: Haishen. As of 5:30am ISTIt has a windspeed of 135 knots, making it the second most powerful cyclone of the year in the northern hemisphere

Info from Vag. Vineetkumar (Pune IITM)




September 3rd 2020:

Maysak typhoon with maximum windspeed of 125 knots is the strongest typhoon and only the first category 4 typhoon in entire pacific ocean in year 2020.
Its lowest pressure: 921 hpa
Durration with windspeed more than 65 knots : 4.5 days. Highest by any typhoon in entire pacific ocean this year

Info from Vag. Vineetkumar (Pune IITM)


Hurricane Laura and the Wind Speed Dilemma

Reposted from the Cliff Mass Weather Blog

Thursday, August 27, 2020

Hurricane Laura and the Wind Speed Dilemma

Last night, Hurricane Laura made landfall on the southwestern coast of Louisiana, bring heavy rain (6-8 inches),  strong winds (gusting to 132 mph at one location), and a coastal storm surge (roughly 10 feet at the most vulnerable locations).

The NWS Lake Charles radar image at midnight central time showed a well defined eye as the storm was making landfall.

Now the dilemma and interesting part.  Based on reconnaissance aircraft and other information, the National Weather Service’s National Hurricane Center had estimated that Laura was a Category Four hurricane just prior to landfall, and according to the official Saffir-Simpson scale, that means the sustained surface (10-m) winds, averaged over a few minutes, were between 130 and 156 mph (see below).  Not gusts, sustained winds.

Saffir-Simpson Hurricane Categories

But here is the issue.  What were the maximum sustained winds that occurred last night as Laura made landfall?   Looking at all available stations, the highest sustained wind was 98 mph at Lake Charles Airport.  The map below shows the sustained winds at 1 AM, when the storm was just moving inland (wind barbs show sustained winds, with gusts in red).  The blue arrow indicates Lake Charles Airport.

Looking at the sustained winds, one would conclude that Laura was only a weak category two hurricane (96-110 mph).

And then there are gusts.  Gusts are not used as part of the Saffir-Simpson hurricane scale, but, let’s face it, gusts are very important.  The big damage in most storms are done by the gusts.

Below are the maximum gusts of Laura. Two locations are extreme: Calcasieu Pass on the coast and Lake Charles, a few miles to the north (127 and 132 mph gusts, respectively)

Such strong gusts are consistent with the destruction of the NWS radar dome at Lake Charles Airport–they are rated to handle up to about 135 mph. (see the before and after below).  

So what is going on?  How strong was the storm?  Category two or four?

A key issue is friction and drag, which is much greater over land (with trees, hills, buildings, etc) that over the aerodynamically smooth water.   As a result of this surface drag, winds decrease VERY rapidly over land, even if the hurricane remains relatively intact aloft. 

Let me illustrate this visually, by showing you a forecast by the state-of-the-art NOAA/NWS HRRR model as Laura made landfall.  These plots show surface (10-m) surface wind in knots (1 knot=1.15 mph)

Before landfall (9 PM PDT), a nice hurricane structure is apparent, with some winds getting to 90 knots in the eyewall.

But then as the storm makes landfall (1 AM PDT), you can see a profound weakening of winds over land.

And by 5 AM PDT, with the storm completely over land, the fastest winds are gone.

So even if the storm had category four sustained winds near the surface while it is offshore,  the sustained winds decline precipitously when the store goes onshore.

But yet the storm can still remain very, very dangerous in the hours after landfall.
Why?

First, even the reduced sustained winds (e.g., 90-100 mph in this case) can produce great damage.

But there is more.  Gusts don’t necessarily decline as rapidly as sustained winds as the storm moves over land.

To illustrate this, here is a plot of the  predicted gusts as the storm made landfall.  Not as much a decline over land as for sustained winds.  Gusts are caused by the intermittent mixing down of faster (higher momentum) air from aloft down to the surface.  So even if winds are slower down lower, sometimes air from aloft…where the winds are still blowing hard…can be mixed to the surface.  So gusts can hold out longer than sustained winds as a storm makes landfall.

The bottom line: a storm that was category four over water can still maintain a real “punch” over land, even after it nominally declines to a category two. Strong, damaging gusts can remain, even when the sustained winds decline.

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28th august 2020 :Phoenix Has Record-Breaking Heat Wave With 50 Days Of 110°F...43.3c

Phoenix, Arizona Is In The Midst Of An Unprecedented Record-Breaking Heat Wave, Hitting Its 50th Day This Year With Temperatures Reaching 110 Degrees Or Higher On Friday.

Although scorchingly hot summer temperatures are common in the desert city, the current year has broken earlier records for consistently high temperatures by some distance. The previous record for the most days at 110 degrees or higher in one year was 33, which occurred in 2011.

On August 16, a temperature of 130 degrees was recorded at California’s Death Valley. The reading was the third-highest temperature ever recorded. The highest-ever temperature was also recorded at Death Valley, where a temperature of 134 degrees was observed on June 10, 1913, while 131 degrees was recorded in Tunisia on July 7, 1931.
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Japan Heat Wave Records...17th -20th August 2020

Tokyo (CNN)Temperatures in central Japan tied for a national record on Monday, as the country sweltered under a scorching summer heat wave.

The mercury rose to 41.1 degrees Celsius (105.98 degrees Fahrenheit) in the central city of Hamamatsu, in Shizuoka prefecture on Monday, according to the Japan Meteorological Agency, matching the highest temperature ever recorded in the country, which was set in Kumagaya, a city near Tokyo, in July 2018.
Japan has been enduring an intense heatwave since the middle of last week, with multiple cities and prefectures nearing 40°C (104°F) for several consecutive days.
    To compare, the average daytime temperature in August for Hamamatsu between 1898 and 2010 was 31.3°C (88.34°F), the JMA said. Last year, average temperatures in Japan reached the highest level since records began in 1898, and were almost a degree warmer than a typical year, according to the JMA.
    "Monday was a scorching hot day (like) I've never experienced, I was wearing a mask outside and drenched in sweat in the heat," said Satoru Shoji, who works at the Hamamatsu tourism office.
    On Monday, cities in Nagano, Gifu, Nara, Kochi and Miyazaki prefectures -- covering central and southwestern Japan -- saw temperatures above 39°C (102.2°F).
    Residents in the capital Tokyo broiled in 36.5°C weather, and have endured three straight days of temperatures above 35°C. Meanwhile, Osaka posted a high of 37.1°C (98.7°F) on Monday, and the popular tourist town of Kyoto reached 38.7°C (101.6°F)

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    August 2020: Double Cloud Trouble

    Double Cloud Trouble

    Australian meteorologists took note recently when not one—but two—vast bands of clouds stretched from the eastern Indian Ocean to Australia, channeling streams of moisture that delivered intense rains to both sides of the continent.

    Moisture-transporting atmospheric rivers occur all over the world and regularly hit Australia, but it is rare for two of the rainmakers to hit at once, according to Australia’s Bureau of Meteorology. One of them delivered more than 150 millimeters (6 inches) of rain in less than 24 hours to Western Australia’s Nullabar Coast, a dry area that typically receives 24 millimeters of rain in the whole of August. The second system dropped large volumes of rain on New South Wales.

    The Visible Infrared Imaging Radiometer Suite (VIIRS) on the NOAA-NASA Suomi NPP satellite captured this natural-color image of the cloud bands on August 10, 2020.

    Atmospheric rivers are often called Northwest Cloud Bands in Australia. The same type of event in the United States is colloquially called the Pineapple Express, because it brings moisture from the tropical Pacific near Hawaii to the U.S. West Coast.

    There are some indications that the frequency of atmospheric rivers could be increasing as global climate changes. After searching through 30 years of satellite data (1984-2014) for Northwest Cloud Bands affecting Australia, a team of University of Melbourne researchers concluded that the number of cloud band days had increased by nearly one day per year over the study period.

    NASA Earth Observatory image by Joshua Stevens, using VIIRS data from NASA EOSDIS/LANCE and GIBS/Worldview and the Suomi National Polar-orbiting Partnership. Story by Adam Voiland.



    Most Exteme Temperatures in the history of every State in U.S.


    https://twitter.com/i/status/1289219775571296257


    Death Valley records highest temperature in the world in more than 100 years

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    Tourists walk in the Mesquite Dunes of Death Valley National Park, Calif., in 2013. A weather station at the park recorded a temperature of 54.4 C Sunday, the hottest temperature in the world in more than 100 years. (REUTERS)

    "If verified, this will be the hottest temperature officially verified since July of 1913," NWS Las Vegas, which owns the automated observation system, said of the reading on Sunday afternoon, emphasizing that it was preliminary.

    It will need to undergo a formal review before the record is confirmed because of its significance, NWS said on its Twitter feed, linking to a statement.


     Death Valley high temperature record of July 10, 1913

    From "Whatts up with That"

    *On July 10,Temperature recordings at the Greenland Ranch weather station in Death Valley, California during the intense heat wave of July 1913.  This excerpt about the record-breaking heat wave comes from an article posted during January 1922 in the meteorological journal Monthly Weather Review which is still in publication today. Source: NOAA 1913, Death Valley, California reached an amazing 134 degrees…the hottest temperature ever reliably recorded in a year with many remarkable weather events*
    The high temperature in Death Valley, California on Friday will come close to 120°F, but this is still well short of the all-time record there that occurred way back in 1913. On July 10th, 1913, the weather observer at Greenland Ranch in Death Valley recorded a high temperature of 134°F. One hundred and seven years later, this is still the highest air temperature ever reliably recorded on Earth. In addition to this all-time and worldwide high temperature record, the year of 1913 produced numerous other extreme weather events. 
    The intense heat of July 1913 in California was not the only extreme heat measured that year in the US.  There was a widespread heat wave in June of that same year across the eastern half of the nation which resulted in many readings above 100°F.  In fact, NOAA’s official temperature records still cite June 16, 1913 as the hottest ever on a nationwide basis for that particular date.  In addition to the excessive heat seen across the US that year, there are newspaper articles from that same time period suggesting high heat may have taken place in others part of the world. 
    On September 12th, 2012, the WMO officially re-certified the 134 degree reading of July 10th, 1913 at Death Valley, California as the all-time highest air temperature ever recorded on Earth after evidence surfaced suggesting the Libya record of 136°F was based on a reading from a bad thermometer that was placed in the wrong place (near asphalt) and read by an untrained observer


    Hottest Day Ever in Australia Confirmed: Bourke 51.7°C, 3rd January 1909

    From "Whatts up with That"


    The Australian Bureau of Meteorology deleted what was long regarded as the hottest day ever recorded in Australia – Bourke’s 125°F (51.7°C) on the 3rd January 1909. This record* was deleted, falsely claiming that this was likely some sort of ‘observational error’, as no other official weather stations recorded high temperatures on that day.Australian Bureau of Meteorology deleted what was long regarded as the hottest day ever recorded in Australia – Bourke’s 125°F (51.7°C) on the 3rd January 1909. This record* was deleted, falsely claiming that this was likely some sort of ‘observational error’, as no other official weather stations recorded high temperatures on that day.

     Photograph of the the relevant page from the observations book, and it shows 123°F was recorded at 9am on the morning of Monday 4th January 1909 – published here for the first time. This was the highest temperature in the previous 24 hours and corroborates what must now be recognised as the hottest day ever recorded in Australia of 51.7°C (125°F) degrees at Bourke on the afternoon of Sunday 3rd January 1909.


    photographed by Craig Kelly MP. Note 123F recorded at 9am on 4th January 1909.


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    A Dark Month for Seattle

    There have a lot of complaints about our cloudy weather of the past month--and it has been a bit depressing.

    Yes, western Washington typically "enjoys" a cloudy, June gloom this time of the year, as high pressure builds over the eastern Pacific, pushing cloudy marine air up to the Cascade crest.

    June 29th

    Has this year been particularly bad?  The essential answer: Yes, but not by a lot.

    We can start with the total monthly radiation reaching the ground in Seattle at the WSU AgWeather site near the UW, which only goes back to 2012.  June 2020 was the darkest June since 2012--eight years.  June 2015, when high pressure dominated our region, was far brighter.  2012 was abysmal.

    From Cliff Mass Blog
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    20th June 2020..
    New world record all time Tmax for the polar regions with 38.0C at Verkhoyansk....Info from Max.

    Climate data for Verkhoyansk
    MonthJanFebMarAprMayJunJulAugSepOctNovDecYear
    Record high °C (°F)−9.5
    (14.9)
    −0.3
    (31.5)
    5.6
    (42.1)
    14.3
    (57.7)
    28.1
    (82.6)
    38.0
    (100.4)
    37.3
    (99.1)
    33.7
    (92.7)
    25.1
    (77.2)
    14.5
    (58.1)
    1.1
    (34.0)
    −5.3
    (22.5)
    38.0
    (100.4)
    Average high °C (°F)−42.2
    (−44.0)
    −36.6
    (−33.9)
    −19.7
    (−3.5)
    −3
    (27)
    9.9
    (49.8)
    19.9
    (67.8)
    23.4
    (74.1)
    18.6
    (65.5)
    8.4
    (47.1)
    −9.3
    (15.3)
    −31.1
    (−24.0)
    −40.2
    (−40.4)
    −8.5
    (16.7)
    Daily mean °C (°F)−45.3
    (−49.5)
    −41.6
    (−42.9)
    −29.6
    (−21.3)
    −12.4
    (9.7)
    3.7
    (38.7)
    13.2
    (55.8)
    16.4
    (61.5)
    11.5
    (52.7)
    2.6
    (36.7)
    −14.3
    (6.3)
    −34.7
    (−30.5)
    −43.4
    (−46.1)
    −14.5
    (5.9)
    Average low °C (°F)−48.3
    (−54.9)
    −45.8
    (−50.4)
    −37.9
    (−36.2)
    −22.1
    (−7.8)
    −2.5
    (27.5)
    6.7
    (44.1)
    9.7
    (49.5)
    5.2
    (41.4)
    −2.3
    (27.9)
    −18.9
    (−2.0)
    −38.2
    (−36.8)
    −46.4
    (−51.5)
    −20.1
    (−4.2)
    Record low °C (°F)−67.8
    (−90.0)
    −67.8
    (−90.0)
    −60.3
    (−76.5)
    −57.2
    (−71.0)
    −34.2
    (−29.6)
    −7.9
    (17.8)
    −3.2
    (26.2)
    −9.9
    (14.2)
    −21.7
    (−7.1)
    −48.7
    (−55.7)
    −57.2
    (−71.0)
    −64.5
    (−84.1)
    −67.8
    (−90.0)
    Average precipitation mm (inches)6
    (0.2)
    6
    (0.2)
    5
    (0.2)
    5
    (0.2)
    14
    (0.6)
    27
    (1.1)
    34
    (1.3)
    34
    (1.3)
    19
    (0.7)
    11
    (0.4)
    11
    (0.4)
    8
    (0.3)
    180
    (7.1)
    Average precipitation days (≥ 1.0 mm)2.31.71.52.23.65.26.55.74.04.83.53.244.2
    Average snowy days171512840004171816111
    Average relative humidity (%)74746963585761697478777573
    Mean monthly sunshine hours684219280309354327219132842612,041

    May snowfall in Turkey


    10 May 2020 – “Very rare” May snowfall surprises residents of Ardahan.
    Flaky snowfall imbued the center of the city with white.
    Trees that were prepared to bloom in May were covered by so much snow that branches of some trees were broken.


    10th May 2020


    Latest EVER Snowfall In New York City Central Park

    Unusual Weather:Polar vortex brings record cold temps, snow to the eastern US


    Doug Stanglin
    USA TODAY

    A polar vortex packing bone-chilling temperatures is turning the usually mild Mother's Day weekend into a preview of winter, bringing snow flurries to Manhattan on Saturday and even 10 inches of snow to northern New England.
    The powerful stream of cold air, which normally confines itself to the Arctic, slipped southward instead and brought frigid temperatures and un-springlike snow to Canada and the eastern two-thirds of the United States.
    The National Weather Service says the cold-air blast will hit the Eastern, Central and Southern U.S. during the weekend, with some snow from the Midwest to the Appalachians.
    Some higher elevations in northern New York and New England reported snowfall accumulations Saturday of up to 10 inches, while traces of snow were seen along the coast from Maine to Boston to as far south as Manhattan.
    New York City got in on the action early, with about a half-hour of snow early Saturday. That tied the record, set in 1977, for the latest date in spring snow was documented in Central Park, according to the NWS.
    Detroit, Pittsburgh and New York City's Central Park also posted records low for the day, according to AccuWeather. Washington, D.C., with an overnight low of 37, smashed a 54-year-old record for the lowest day in May. The nation's capital was also flirting with a new record for the coldest high temperature for the day — 52 degrees — set in 1877
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    30th April 2020:

    Can Meteorologists Help Epidemiologists with Coronavirus?

    From Cliff Mass Weather Blog.

    Meteorologists involved in the large U.S. numerical weather prediction community.  And perhaps

    meteorologists can help epidemiologists and the U.S. government to get a handle on the coronavirus situation.


    Now don't take this blog as one uppity weather guy trying to give advice "outside his lane."    A published paper in the Journal of Infectious Diseases (2016), said much of the same, with the authors noting the huge similarities in the work meteorologists and epidemiologists do and suggesting that the epidemiological community is roughly 40 years behind the numerical weather prediction enterprise.  They observed that both epidemiological and numerical weather prediction models are attempting to simulate complex systems with exponential error growth, and thus have great sensitivity to initial conditions.
    So perhaps the experience of meteorologists, who spend much of their time thinking about how to improve weather forecasting, may be relevant to the current crisis.

    The First Step in Prediction:  Describing the Initial State of the System
    To predict the future you need to know what is happening now. The better you can describe the initial starting point of forecasts, the better the forecast.
    Meteorologists have spent 3/4 of a century on such work, first with surface observations and balloon-launched radiosondes, and later with radars and satellite observations.  Billions have been invested in the weather observing system, which gives us a three-dimensional observational description of atmospheric structure.  Big data.  And we have learned how to quality control and combine the data with complex data assimilation techniques, with the resulting description of the atmosphere immensely improving our predictions.  This work is completed operationally by large, permanent groups such as NOAA and NASA, with large interactions with the research community.

    Contrast this to the unfortunate state of epidemiologists predicting the future of the coronavirus.

    They have very little data on what is happening now.  They don't know who in the population is currently infected or has been infected.  They don't even know the percentage of the current population that is infected.   Without such information, there is no way epidemiologists can realistically simulate the future of the pandemic.  They are trying, of course, but the results have been disappointing.

    Meteorologists use complex, full-physics models comprised of equations that predict the future  evolution of the atmosphere.  Then we apply statistical corrections to make the forecasts even better.

    The meteorological community has a long and successful track record in an analogous enterprise, showing the importance of massive data collection to describe the environment you wish to predict, the value of sophisticated and well-tested models to make the prediction, and the necessity to maintain a dedicated governmental group that is responsible for state-of-science prediction.

    Perhaps this approach should be considered by the infectious disease community. and the experience of the numerical weather prediction community might be useful.

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    20th April2020











    Denver breaks low temperature record set 119 years ago


    Record low for the second day in a row.
    Denver International Airport set a record low temp yesterday of 12F, according to the National Weather Service. The previous low temp for April 17 of 13F was set in 1901.
    DIA also set a record low on Thursday when reaching 19 degrees, breaking the old record of 22 degrees.
    On Thursday, Northern Colorado was on a Winter Storm Warning with 14 inches of snowfall in Fort Collins and 12 inches in Denver.
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    Krakatoa erupting again – Video

    Violent eruption propels ash to 47,000 ft (15 km) altitude
    10 Apr 2020 – The famous volcano, located between the islands of Java and Sumatra in the Indonesian province of Lampung, reportedly began erupting at 10:35 p.m. local time.
    “Krakatau is erupting nonstop for 2 hours,” one social media user posted. “I live in Bogor and I can hear the noises as clear as everybody else hear. This feels like a nightmare”.
    The volcano’s rumble was heard very clearly in West Java and Indonesia’s capital of Jakarta.
    Satellite images picked up a large magmatic eruption of ash and plume propelled into the sky.

    View from Webcam
    According the The Express, the eruption was “relatively small”, with less material thrown high than in previous eruptions.
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    Thursday, April 2, 2020

    It's Bizarre: March was Colder than January In Seattle



    Everything seems topsy turvy and unnatural these days, and there is a meteorological oddity that must be added to the list:

    March was cold than January in Seattle this year.

    I knew March was a cool one, but it was not until Dr. Joseph Zagrodnik, a talented atmospheric scientist working at WSU's AgWeatherNet organization, pointed in out to me, did I realize how unusual the past month had been.

    According to Dr. Zagrodnik, the average temp in March at Sea-Tac Airport was 44.8 degrees F compared to 45.1 F in January.

    How unusual is this?  Rare, but not unprecedented.  March has been cooler than January 8 times in the 126 years we have temperature records in Seattle, with the last time it occurred in 2006.

    To appreciate this oddity visually, the graph below shows the numbers of year the March minus January temperatures fell in various bins.  On average, March is about 5F warmer than January, but in some extreme years March has been as much as 17F warmer.  That would get folks attention. Ten years were close to zero (within .5F of zero) and only a handful (3) were .5 to 1.5F cooler in March.

    Another way to appreciate our cool March would be to look at a map of the difference of this year's March temperature from normal  (see below).  Western Washington was much cooler than normal, with some areas 4-5F cooler than typical values.    More normal temperatures east of the Cascade crest.

    I know your next question: Why?

    A good question. It has to do with an unusual weather pattern that has persisted over the North Pacific during the past month, one that includes a ridge of high pressure offshore with persistent cool, northerly flow over the Northwest.

    The figure below  shows the  height (like pressure) anomalies (difference from normal) around 18,000 ft above the surface (500 h Pa pressure).  Unusually high heights offshore (red) and lower than normal heights (blue/purple).  This is a cold pattern for us, with unusually strong/cold northerly flow over the Northwest coast.

    Finally, I wanted to show you an extraordinary picture taken yesterday (Wednesday) around 5:20 PM from the Seattle SpaceNeedle PanoCam.   With cold air aloft and great instability, there was a magnificent line of cumulus clouds along the western slopes of the Cascades.  Just stunning.


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    Volcanic activity worldwide 28 Mar 2020: Popocatépetl volcano, Merapi, Ibu, Dukono, Reventador, San...

    Saturday Mar 28, 2020 21:00 PM | BY: SEVERAL CONTRIBUTORS

    Map of today's active volcanoes
    Map of today's active volcanoes
    Satellite image of Ibu volcano on 27 Mar 2020
    Satellite image of Ibu volcano on 27 Mar 2020
    Satellite image of Merapi volcano on 28 Mar 2020
    Satellite image of Merapi volcano on 28 Mar 2020
    Ibu (Halmahera, Indonesia)(27 Mar) Volcanic Ash Advisory Center Darwin (VAAC) issued the following report: VA TO 5200FT ABOVE SEA LEVEL.

    Merapi (Central Java, Indonesia): Volcanic Ash Advisory Center Darwin (VAAC) issued the following report: ERUPTION OBSERVED ON WEBCAM OBS VA DTG:28/1235Z

    Dukono (Halmahera): Explosive activity continues. Volcanic Ash Advisory Center (VAAC) Darwin warned about a volcanic ash plume that rose up to estimated 7000 ft (2100 m) altitude or flight level 070 and is moving at 5 kts in N direction.
    The full report is as follows: CONTINUOUS VA EMISSION TO FL070 OBS VA DTG:28/1830Z to 7000 ft (2100 m)

    Popocatépetl (Central Mexico): Explosive activity continues. Volcanic Ash Advisory Center (VAAC) Washington warned about a volcanic ash plume that rose up to estimated 22000 ft (6700 m) altitude or flight level 220 .
    The full report is as follows: VA EM OBS IN STLT. to 22000 ft (6700 m)

    Nevado del Ruiz (Colombia): Explosive activity continues. Volcanic Ash Advisory Center (VAAC) Washington warned about a volcanic ash plume that rose up to estimated 22000 ft (6700 m) altitude or flight level 220 .
    The full report is as follows: VA EM RPRTD. to 22000 ft (6700 m)

    Sangay (Ecuador)(28 Mar) Explosive activity continues. Volcanic Ash Advisory Center (VAAC) Washington warned about a volcanic ash plume that rose up to estimated 22000 ft (6700 m) altitude or flight level 220 and is moving at 10 kts in SW direction.



    Scientists recording the first-ever heatwave event in Antarctica over the 2019-20 summer period.
    Researchers from the Australian Antarctic Program recorded the heat wave at the Casey Research Station — located on the northern part of Bailey Peninsula on the Budd Coast — between January 23 and 26, which falls in the region’s summer season.
    During the three days, minimum temperatures climbed above zero, and maximum temperatures reached above 7.5 degrees Celsius. On January 24, its highest maximum of 9.2°C was recorded, almost 7°C above Casey’s 30-year mean for the month.


    “Heatwaves are classified as three consecutive days with both extreme maximum and minimum temperatures,” University of Wollongong biologist Sharon Robinson explained.

    “In the 31-year record for Casey, maximum temperature of 9.2 degrees Celsius is 6.9 degrees Celsius higher than the mean maximum temperature for the station, while the minimum is 0.2 degrees Celsius higher,” Robinson said.


    31st March 2020
    Messgae from Maximiliano from Thailand :
    "Hallo Rajesh
    Hottest T ever of March in THailand 42.9C yesterday and today recorded at Thoen.
    Also hottest March ever nationwide as always.
    Every month Thailand is setting records heat,never been below average not even a single day of the year.
    Heat indexes are expected to rise around 70C next weeks."

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    Earth’s third-highest summit, Kanchenjunga, rises more than 8500 meters above sea level along the border of Nepal and India.
    Image of the Day for March 29, 2020



    31st March 2020






    Last Friday, 20th March 2020,  Antarctica set a record for its coldest March temp ever recorded, not just for the day, but for the entire month.
    The Vostok Station clocked a bone-chilling -75.3C (-103.54F) on the morning of Friday, March 20, as spotted by @TempGlobal on Twitter:

    Antarctica Melts Under Its Hottest Days on Record

    Antarctica Melts Under Its Hottest Days on Record
    On February 6, 2020, weather stations recorded the hottest temperature on record for Antarctica. Thermometers at the Esperanza Base on the northern tip of the Antarctic Peninsula reached 18.3°C (64.9°F)—around the same temperature as Los Angeles that day. The warm spell caused widespread melting on nearby glaciers.
    The warm temperatures arrived on February 5 and continued until February 13, 2020. The images above show melting on the ice cap of Eagle Island and were acquired by the Operational Land Imager (OLI) on Landsat 8 on February 4 and February 13, 2020.
    The heat is apparent on the map below, which shows temperatures across the Antarctic Peninsula on February 9, 2020. The map was derived from the Goddard Earth Observing System (GEOS) model, and represents air temperatures at 2 meters (about 6.5 feet) above the ground. The darkest red areas are where the model shows temperatures surpassing 10°C (50°F).
    Mauri Pelto, a glaciologist at Nichols College observed that during the warming event, around 1.5 square kilometers (0.9 square miles) of snowpack became saturated with meltwater (shown in blue above). According to climate models, Eagle Island experienced peak melt—30 millimeters (1 inch)—on February 6. In total, snowpack on Eagle Island melted 106 millimeters (4 inches) from February 6- February 11. About 20 percent of seasonal snow accumulation in the region melted in this one event on Eagle Island.
    “I haven’t seen melt ponds develop this quickly in Antarctica,” said Pelto. “You see these kinds of melt events in Alaska and Greenland, but not usually in Antarctica.” He also used satellite images to detect widespread surface melting nearby on Boydell Glacier.
    Pelto noted that such rapid melting is caused by sustained high temperatures significantly above freezing. Such persistent warmth was not typical in Antarctica until the 21st century, but it has become more common in recent years.
    The warm temperatures of February 2020 were caused by a combination of meteorological elements. A ridge of high pressure was centered over Cape Horn at the beginning of the month, and it allowed warm temperatures to build. Typically, the peninsula is shielded from warm air masses by the Southern Hemisphere westerlies, a band of strong winds that circle the continent. However, the westerlies were in a weakened state, which allowed the extra-tropical warm air to cross the Southern Ocean and reach the ice sheet. Sea surface temperatures in the area were also higher than average by about 2-3°C.
    Dry, warm foehn winds also could have played a part. Foehn winds are strong, gusty winds that cause downslope windstorms on mountains, often bringing warm air with them. In February 2020, westerly winds ran into the Antarctic Peninsula Cordillera. As such winds travel up the mountains, the air typically cools and condenses to form rain or snow clouds. As that water vapor condenses into liquid water or ice, heat is released into the surrounding air. This warm, dry air travels downslope on the other side of the mountains, bringing blasts of heat to parts of the peninsula. The drier air means fewer low-lying clouds and potentially more direct sunlight east of the mountain range.
    “Two things that can make a foehn-induced melt event stronger are stronger winds and higher temperatures,” said Rajashree Tri Datta, an atmospheric researcher at NASA’s Goddard Space Flight Center. With warmer air in the surrounding atmosphere and ocean, the conditions were conducive this month for a foehn wind event.
    This February heatwave was the third major melt event of the 2019-2020 summer, following warm spells in November 2019 and January 2020. “If you think about this one event in February, it isn’t that significant,” said Pelto. “It’s more significant that these events are coming more frequently.“
    NASA Earth Observatory images by Joshua Stevens, using Landsat data from the U.S. Geological Survey and GEOS-5 data from the Global Modeling and Assimilation Office at NASA GSFC. Story by Kasha Patel.

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