Showing posts with label Rainbow Images. Show all posts
Showing posts with label Rainbow Images. Show all posts

Sunday, 4 January 2015

#SAWeather and #Disaster #Observations South Africa : 4 January 2015 04h00 SAST - MSBWX

SAWS SEVERE WEATHER ALERTS: 
 
WARNINGS: Extremely high fire danger conditions are expected in places over the extreme western part of Northwest and the eastern and northern parts of the Northern Cape 

WATCHES: Severe thunderstorms with large hail and damaging wind is expected over the western part of Kwazulu-Natal.

SPECIAL WEATHER ADVISORIES: Hot and humid weather will result in extremely uncomfortable conditions over the Lowvelds of Mpumalanga and Limpopo as well as extreme northeastern part of Kwazulu-Natal. 

MSBWX National Severe Weather Observations:  A few isolated thunderstorms reported yesterday in  Gauteng and Kwazulu Natal. Reports were received of hail in the following areas yesterday: Roodepoort, Krugersdorp, Randburg, Alberton, Edenvale, Northriding, Weltervredenpark, Faere Glen, Garsfontein, Meyerdal & Pretoria East. No damage reports were received up to now. Reports were also received of flooding in areas of Gauteng and Kwazulu Natal.










Images: Twitter via SAWXREP (Click on images for larger view.)

MSBWX General Weather Observations: Cool, warm to very hot conditions expected today over parts of SA. Thunderstorms and rain showers can be expected in parts of  Gauteng, Mpumalanga, Limpopo, North West, Free State and Kwazulu Natal. Light rain is expected along the coastal parts of the Eastern Cape.

MSBWX National Disaster Observations:   Several drownings already occurred during the holiday season in South Africa. Drownings are preventable. Heed lifeguard warnings and swim under supervision, in demarcated and designated areas. We need to be vigilant and alert at all times especially were children are playing or swimming in water.

NSRI National Warnings: SPRING TIDE RIP CURRENT WARNING: With more people on the beaches at this time of the year NSRI are urging the public to be extra cautious between now and the 8th January during the Full Moon Spring Tide, which will peak on the full moon on Monday 05 January and that will cause stronger than normal rip currents around the coast starting from today, peaking on Monday 05th January and lasting until around the 09th January. NSRI are urging extreme public caution around the coast over the next 8 days. The main concern is that a lot of people will be on beaches over this weekend as the Spring Tide builds towards peaking on Monday 5th. The FULL MOON SPRING TIDE peaks on Monday 05th January. Very strong rip currents will be present around the coast from today and over the next 8 days. Bathers and shoreline anglers are most at risk and extreme caution is advised Spring Tide happens twice every month, at full moon and at new moon. Spring Tides bring a higher than normal high tide and a lower than normal low tide, causing stronger than normal rip currents, for a few days leading up to the full moon and the new moon, peaking on the day of the full moon and new moon and lasting for a few days after the full moon OR new moon. There are two high tides and two low tides every day. During Spring Tide the twice daily high tides are higher than normal and the twice daily low tides are lower than normal and while rip currents are always present and dangerous the Spring Tide creates stronger than normal rip currents and hence the danger is increased. Rip Currents are caused when the water reaching the shoreline in waves, swells and sea currents needs to find a way to retreat back into the sea and this is achieved in rip currents (a river of water retreating through the incoming swells back out into the sea). There are two types of rip currents, permanent rip currents, found alongside islands, rocky outcrops jutting into the sea, at river mouths, in between reefs and alongside harbour walls and piers, are found constantly occurring in the same place allowing the water reaching the shoreline to retreat back into the sea in the permanent rip current. Temporary rip currents, found along beach fronts (along the shoreline), are forever changing their position and are unpredictable and can form suddenly along a beach front without warning at different places along the shore front throughout the day. During Spring Tide these permanent rip currents and temporary rip currents are stronger than normal and although rip currents at all times pose a danger to bathers they pose the greatest danger during the Spring Tide. Bathers are at risk of being swept out to sea by rip currents while swimming or wading in water along the beach front. Even bathers wading in shallow water who find themselves trapped in a rip current that forms suddenly are at risk of being swept out to sea by rip currents. Bathers caught in a rip current should not panic. Simply stay afloat by treading water (moving your arms and legs in circular movements), don’t try to swim against the current as it will only cause you exhaustion and let the current sweep you out to sea but at your first opportunity swim parallel to the beach front until you are free of the rip current and then use the incoming waves to get back to shore. While this is happening scream for help and wave your arm to alert people on the beach to raise the alarm. Swim at beaches where lifeguards are on duty and obey the instructions of the lifeguards and only swim within the safe swimming zones lifeguards mark (using their red and yellow flags). Children should have responsible adult supervision at all times around coastal and inland waters and at swimming pools. Anglers fishing along the shoreline, particularly along rocks on the shoreline, are at greatest risk during the Spring Tide where incoming waves during the high tides engulf higher than normal over rocks. Anglers should not turn their back to the sea and should be vigilant and cautious of the wave action at all times while fishing. Boaters, paddlers, sail boarders and anyone launching any kind of craft onto water should wear their life-jackets at all times while on water and carry easily accessible safety equipment - red distress flares, communications cellphone or VHF radio with fully charged batteries in water tight plastic sleeves, a waterproof torch, highly visible neon coloured clothing, a referee whistle worn around the neck, a silver emergency foil blanket, and let a responsible person know your time of departure, your exact intended route and your estimated return time, stick to your plans and check in with the responsible person on your safe return. (If you are overdue the responsible person should raise the alarm without hesitation). -ENDS- TO REPORT A SEA RESCUE EMERGENCY DIAL 112 FROM A CELLPHONE  - NSRI

- MSBWX + SAWXREP + SAWS

Sunday, 19 October 2014

First-ever image of 5th order rainbow!

The fabled quinary or 5th order rainbow is made by sunlight reflected five times inside raindrops. Now, for the first time, we have an image of one.


The familiar primary and secondary rainbows have been known since there were eyes. The long sought 3rd and 4th order rainbows were finally imaged in 2011. Now we have the 5th order!

Harald Edens’ discovery image was taken on August 8, 2012 from the Langmuir Laboratory for Atmospheric Research near the 10,800-foot summit of South Baldy Peak, New Mexico, USA. This is the first-ever image on which the 5th order rainbow is positively identified. This version is considerably enhanced. The raw camera image is here (link to image).

The 5th order lies between the primary and secondary rainbows in the dark sky of Alexanders dark band, where there is no primary or secondary rainbow light.


The fabled quinary or 5th order rainbow is made by sunlight reflected five times inside raindrops. We see only its broad greens tending to blue towards the primary bow. Its yellows and reds are hidden behind the secondary bow.

Harald has now photographed the 5th order several times. He ascribes his success to the very bright rainbows formed locally from small thunderstorms and to the exceptionally clear high altitude low density air. Astute observation over many years by an atmospheric optics expert also helps somewhat! His scientific account will be published in the Journal of Applied Optics.

- EarthSky