A cut-off low pressure system developed earlier in the week
The past week has seen excessive flooding occurring throughout the northern and north eastern parts of South Africa, as well as into neighbouring countries. The rains, which started over a week ago now, primarily in Mozambique spread further south and began impacting South Africa mid to late last week. Thohoyandou Wo, in the Limpopo Province recorded in excess of 150mm in a 24 hour period on Saturday, with accumulative figures over the past several days passing 300mm in areas.. The weather service began issuing warnings already early last week with the regards to the heavy rain and appealed to the public to take care and prepare for potential flooding.
The storm system has me scratching my head a bit in regards to a classification on exactly what type of storm it is. With the limited amount of resources I currently have related to the development phases of the system, it appears as though it started off as an upper trough which then developed into a cut-off low. The interesting part comes in here though, instead of maintaining a classic cut-off low appearance where convection associated with the storm is generally somewhat sparse and the core void of convection, this storm appears to have followed the same evolution as a tropical cyclone would.
A low pressure develops, and as it tightens its core, convection will build over the center of the storm. The unusual aspect here being that it’s supposed to happen over water and not over land, we rarely ever see systems that build this much convection over their center over land. While a MCS type event was considered originally, an MCS tends to only last for a few hours usually and don’t generally occur over the center of a low pressure system.
Another question to ask is: Is there the possibility of this system becoming a classified tropical depression as it moves east over warm summer waters?
Regardless, conditions look to remain wet and dangerous for large parts of the north eastern areas of South Africa, as well as southern Mozambique.
To follow the discussion on this weather system you can view our: Forum Thread