Tue, 22 Jul 2014
METROCAST | 




SA REGIONAL




INFORMATION




You are in: Weather > SA regional > Ecucation


COASTAL LOWS

A coastal low is a shallow low pressure system limited to the lower layers of the atmosphere and is formed when the wind blows from the land TO the sea, usually during bergwinds. These coastal low pressure systems usually form off the Namibian or West Coast of SA. They then slowly move doen the coast and round the SW Cape and then move up the East Coast of SA where they finally fill up along the Mozambique coast where the plateau ceases to exist. Click on the minimised image below to view a larger diagram showing how the coastal low is formed.


Click to view a larger image.

Air moves off the coast at a height of approximately 1500m. This creates a relative "vacuum" at the surface as air rises to replace the air that is moving away from the coast. In a low pressure system, air rises clockwise in the southern hemisphere and the resultant circulation around the low pressure is the same. Hence, prior to the presence of a coastal low, the winds are usually offshore and in Cape Town they are usually in the form of hot, dry NE bergwinds. Once the coastal low moves through the area, the hot, dry winds are replaced by cool, moist NW-SW winds and usually fog. Coastal lows usually precede cold fronts in winter.


Click to view a larger image.

Click on the minimised image above to view a larger image showing the various synoptic features associated with a coastal low.

[ back ]

Search
Goodstuff



Goodstuff
ALEXANDER BAY 19/10
ALLDAYS 22/06
BEAUFORT WEST 17/06
BELA-BELA 21/06
BETHLEHEM 16/00
BISHO 24/08
BLOEMFONTEIN 17/03
CALVINIA 17/06
CAPE ST LUCIA 24/16
CAPE TOWN 16/10
CLANWILLIAM 17/08
DE AAR 18/04
DURBAN 22/15
EAST LONDON 23/14
ERMELO 17/02
FAURESMITH 18/04
FICKSBURG 15/-2
GEORGE 20/08
GRAAF-REINETT 17/05
GRAHAMSTOWN 23/10
HERMANUS 17/09
JOHANNESBURG 18/03
JOUBERTINA 19/11
KIMBERLEY 22/06
KLERKSDORP 19/05
KOMATIPOORT 23/10
KROONSTAD 17/03
LADYSMITH 19/01
LANGEBAAN 18/11
LEPHALALE 20/07
LYDENBURG 20/04
MAFIKENG 20/06
MUSINA 24/09
NELSPRUIT 20/05
NEWCASTLE 19/05
OUDTSHOORN 19/08
PAARL 17/04
PHALABORWA 25/11
PIETERMARITZBURG 21/06
PLETTENBERG BAY 19/13
POLOKWANE 21/05
PORT ALFRED 23/13
PORT ELIZABETH 22/14
PORT ST JOHNS 23/11
POTCHEFSTROOM 19/04
PRETORIA 19/04
QUEENSTOWN 18/04
RICHARDS BAY 24/17
ROBERTSON 17/04
RUSTENBURG 18/04
SASOLBURG 19/03
SKUKUZA 23/09
SOWETO 18/03
SPRINGBOK 19/05
STILBAAI 18/11
SUTHERLAND 16/05
TZANEEN 22/05
ULUNDI 24/10
UMTATA 22/05
UPINGTON 23/08
VEREENIGING 18/04
VREDENDAL 17/08
VRYBURG 20/07
WELKOM 19/03
WITBANK 19/05
WORCESTER 17/04

 

| DISCLAIMER | FEEDBACK | ABOUT US | ADVERTISING | CONTACTS | SERVICES & PRODUCTS |

©COPYRIGHT 1995-2010, CUSTOMWEATHER,INC
San Francisco, California, USA
Your use of this site constitutes your acceptance of
the LEGAL RESTRICTIONS AND TERMS OF USE