Category: <span>SAWS</span>

Impact Based Weather Warnings for Western Cape and Namaqua

Please find included the Impact Based Warning for the Western Cape and Namaqua Region of Northern Cape

Legal notice:  “This warning from SA Weather Service must be communicated as received and may not be altered under any circumstance.  It must be forwarded or communicated in its entirety and no portion hereof may be replicated or copied and distributed.”

 Hazard Alert Level Affected Municipalities Valid From(SAST) Valid To(SAST)
 Damaging Winds Yellow(L1) City of Cape Town, M_Cape Agulhas, M_Cape Agulhas, M_City of Cape town, M_Hessequa, M_Overstrand, M_Saldanha Bay, M_Swartland, M_Table Bay 19/04/21 05h00 20/04/21 23h00

Discussion: A high-pressure system south-west of the country will result in strong, south-easterly winds along the south-west coast of the Western Cape, and in places over Cape Metropole. Wind speed will be between 40 to 65km/h, with gusts reaching 75km/h. The wind are expected to moderate north of Slangkop on Tuesday morning. Along with the strong winds, wave heights of 4.5m between Cape Point and Cape Agulhas are expected resulting in very rough and choppy seas.

Impact: Considering warm, dry and windy conditions there is risk of additional fires are possible along with the further spreading of the Devils Peak fire. Furthermore, some transport routes, as well as high-sided vehicles, might be affected and/or blown over due to crosswinds. Some localised structural damage is also possible. For the coastal waters, difficulty in navigation of small vessels and personal water crafts such as kayaks are likely. There is also a risk for these small vessels to take on water and capsize in totality.

Instruction: Be aware of the following: – sudden crosswinds if travelling especially between buildings, fallen trees or power lines and debris on roads. Ensure that all temporary structures are well anchored and refrain from starting uncontrolled fires.

Report any weather related incidents to the Garden Route Disaster Management Centre at:

044 805 5071.

SOUTH AFRICAN WEATHER SERVICE
Cape Town Weather Office
2nd Floor: Oval Office Park
Cape Town Int airport
Freight Road
Matroosfontein
Cape Town

Impact-based warning: Rain which could lead to localised flooding- Western Cape Province

In light of this severe weather alert as produced by the South African Weather Service (SAWS) and other centers, the following advisory guidelines are suggested. It is emphasized that these advisories are broad guidelines and should be interpreted considering the local aspects of the region such as soil types, cultural preferences and farming systems. Depending on the particular region, the prioritization of the guidelines will differ. The basic strategy to follow would be to minimize and diversify risk. The province should further simplify, downscale and package the information according to their language preference and if possible use local radio stations and farmers’ days in disseminating the information.

Impact-based warning issued by SAWS valid: 15 March 2021

Yellow (level 1) warning for rain could lead to localized flooding of roads and settlements over the coastal areas of the Overberg and Garden Route Districts in the Western Cape.

Heavy rainfall raises the water level. When the water level is higher than the river banks or the dams, water flows out from the river and flooding occurs.

Preventive measures:

  • Construction of proper drainage systems – Drains must be cleaned constantly as they ensure proper water irrigation.
  • Mechanical land treatment of slopes such as contour ploughing or terracing to reduce the runoff coefficient.
  • Construction of small water and sediment holding areas.
  • Construction of floodways (man-made channels to divert floodwater).
  • Terracing hillsides to slow flow downhill.

What to do when flooding is forecasted:

Avoid-

  • Cutting grass in the rainy season (nutrient depletion).
  • Applying fungicides and pesticide (plants and animals).
  • Applying N fertilizer (burning of plants) (Nitrogen loss is higher during heavy rain), immediately follows a surface application of fertilizer, especially on sloped areas.
  • Dumping fertilizer in one spot can cause the roots below the fertilizer to be burned and die.
  • Irrigation (waterlogging can occur, nutrient depletion).

–  Cover Urea licks to prevent them from becoming toxic.

–  Provide shelter for animals (young ones die easily).

–  Leave cultivated areas coarse.

–  Relocate/ move animals to a safe place.

The following are a number of concerns and recommendations:

  • Be extra cautious for pest and diseases after the rain has fallen, as high moisture content and high temperatures may trigger these.
  • Assume that floodwater contains sewage and might be harmful for human and livestock consumption.
  • Before leading livestock across a river, check whether the water level is rising. This is especially necessary if it is already raining, but remembers that there could be a storm further upstream and floodwaters could be on the way

A comprehensive list of strategies can be found in the monthly NAC Advisory. It can be accessed from the following websites: www.dalrrd.gov.za. For more information contact:-

Directorate: Climate Change and Disaster Risk Reduction

Private Bag X93

Pretoria 0001

Tel: 012 319 6775

Email: MittaA@Dalrrd.gov.za

Weather Warning information as received from the Department of Agriculture, Land Reform and Rural Development.

Weather forecast 15 – 22 March 2021

Garden Route District Municipality disseminates the information below on behalf of the South African Weather Service.

Today: 15/03/2021

An upper cut-off low-pressure system is dominating the atmospheric circulation resulting in cloudy and rainy conditions over most parts of the province, with rain abating in the West Coast District and Cape Metropole as well as the Northern parts of Cape Winelands during the afternoon. The continuous onshore flow along the Overberg and Garden Route coastal areas will result in localised flooding in these areas as well as disruptions on the roads.

(A warning detailing these impacts has been issued already on 14/03/2021 and it is still on track).

Tomorrow Tuesday, rain will be confined to the Southern parts of the province, especially the coastal areas, persisting into the evening.

Further, into the week, a coastal low pressure will bring foggy conditions along the West and Southwest coastlines on Thursday morning. Cloudy and rainy conditions are expected along the Overberg and Garden Route coast from late Thursday night, persisting into Saturday afternoon, with no risk of impacts at this stage.

Coastal Wind– A strong South Easterly wind of 45 to 55km/h can be expected along the coast today and tomorrow, and again on Friday.

Most recent Spring Tide date: 14 March 2021 at 01:54 SAST

Sea State– 2.5 to 3.0m wave heights with a Southerly swell today into Wednesday and again on Friday into the weekend.

Weather conditions will be monitored during the week and any further developments will be communicated if needs be.

Issued by the South African Weather Service.

Report any severe weather-related incidents to the Garden Route Disaster Management Centre at telephone number 044 805 5071.

Severe weather alert: Impact Based Weather Warnings for Western Cape and Namaqua (14-15 March 2021)

Please find included the Impact Based Warning for the Western Cape and Namaqua Region of Northern Cape

Legal notice:
“This warning from SA Weather Service must be communicated as received and may not be altered under any circumstance.
It must be forwarded or communicated in its entirety and no portion hereof may be replicated or copied and distributed.”

Hazard Alert Level Affected Municipalities Valid from (SAST) Valid to (SAST)
Disruptive rain Yellow (L2) Bitou, Cape Agulhas, George, Hessequa, Knysna, Mossel Bay, Overstrand and Swellendam 14/03/2021 22H00 15/03/2021 09H00

Discussion: Significant rain is expected to affect the coastal areas of the Overberg and Garden Route Districts tonight into tomorrow morning.The accumulated rainfall is likely to reach between 40 to 50mm over the period due to the strong southerly to south-easterly winds aided by an intense upper air system.

Impact: Localised flooding can be expected in susceptible formal and informal settlements and roads. Increased travel times and motor vehicle accidents due to pooling of water may occur along with difficult driving conditions on dirt roads.

Instruction: If possible stay indoors and off the roads, avoid crossing rivers and swollen streams where water is above your ankles. If trapped in a vehicle during a flood, abandon it and climb to higher ground. In buildings, move valuables to a safe place above the expected flood level. Take caution driving on a roads covered by water. Listen to the radio or TV for warnings and obey the instructions from disaster management officers.

>>>Legal notice:<<<

“This warning from SA Weather Service must be communicated as received and may not be altered under any circumstance.

It must be forwarded or communicated in its entirety and no portion hereof may be replicated or copied and distributed.”

Report any weather related incidents to the Garden Route Disaster Management Centre at:
044 805 5071.

Weather forecast: 8 March – 14 March 2021

Garden Route District Municipality disseminates the information below on behalf of the South African Weather Service.

Today will be predominantly cloudy over the province with rain expected along the Eastern parts of the South-coast during the morning. Cloudy conditions are expected from tomorrow until Thursday with the approaching cold front. This will result in strong North-Westerly winds ahead of the front for Tuesday and Wednesday, particularly over the central and Eastern interior as well as over the South-Western coastal areas. The system will result in the rain over the Western parts from Tuesday evening and will spread along the South coast from Wednesday afternoon, clearing during the afternoon of Thursday. 

 The bulk of the rain is expected over the Western parts (20-40mm, 50mm over the mountains). Severe weather warnings will be sent by SAWS later today. The rest of the week will remain sunny to partly cloudy. On Saturday afternoon another cold front will reach the country resulting in cloudy conditions and there is a chance of rain over the South-Western parts from Saturday afternoon that will spread along the south coast during Sunday. The rain will start to clear in the West from Sunday afternoon. Temperatures in the mid to high twenties are expected during the week.

Along the coast the winds are expected to be moderate to fresh South-Westerly today, becoming North-Westerly tomorrow and will remain like that for the rest of the week except on Thursday and Sunday when it will be South-Easterly. Strong winds are expected from tomorrow afternoon until Wednesday night reaching gale force along the South-West coast on Tuesday and Wednesday. 

 Coupled with the strong winds, 4.0 to 6.0m South-Westerly swell is expected along the South coast from tomorrow afternoon until Wednesday afternoon, which will result in very rough and choppy seas. We expect warnings from SAWS later today. Apart from Tuesday and Wednesday, 3.0 to 4.0m South-Westerly swell is expected.

Issued by the South African Weather Service.

Report any severe weather-related incidents to the Garden Route Disaster Management Centre at telephone number 044 805 5071.

Weather Warnings for Western Cape and Namaqua

Impact Based Warning for the Western Cape and Namaqua Region of Northern Cape:

 Hazard Alert Level Affected Municipalities Valid From (SAST) Valid To (SAST)
 Veld Fire Conditions Red(L10) Beaufort West, Hantam, Kannaland, Karoo Hoogland, Khâi-Ma, Laingsburg, Oudtshoorn, Prince Albert 21/11/20 08h00 21/11/20 18h00

Discussion: Weather conditions which includes hot temperatures, fresh to strong winds and low humidity might result in the development of veld/bush fires.

Impact: Conditions are such that the FDI index is above 75. Under these conditions fires may develop and spread rapidly resulting in damage to property and possible loss of human and/or animal life.

Instruction: All personnel and equipment should be removed from the field. Fire teams, labour and equipment are to be placed on full stand-by. At first sign of smoke, every possible measure should be taken in order to bring the fire under control in the shortest possible time.