IMPACTBASED WARNING SYSTEM Severe Weather CASE STUDY Heavy

IMPACT-BASED WARNING SYSTEM: Severe Weather CASE STUDY: Heavy Flooding on 13 & 14 Feb 2019 (Mopani and Vhembe Districts) Presenter: Puseletso Mofokeng Compiler: Dipuo Tawana 2020 -11 -28 Templ ref: PPT-ISO-colour. 001 Doc Ref no: 1

Contents… • • • • Introduction What Recent Literature Says Region of Interest NWP Model Suggestions: Global Forecast System (GFS) Discussion of Potential Weather NWP Model Suggestions: Unified Model (UM) Analyses From Observations (Surface Network + Satellite) SMS Warnings: Sat. images + Rainfall Accumulation Impact-based Warning System Impacts on the Ground Observations: Rainfall Accumulation Remarks Conclusion 2020 -11 -28 Templ ref: PPT-ISO-colour. 001 Doc Ref no: 2

Introduction • The South African Weather Service has committed to create a weather-SMART nation. • • • Safe More informed Alert Resilient Timeous This promise is in alignment with the WMO Guidelines on multi-hazard impact-based forecast and warning services and The Sendai Framework for Disaster Risk Reduction 20152018 - Creating a people centred early warning system. 2020 -11 -28 Templ ref: PPT-ISO-colour. 001 Doc Ref no: 3

Introduction (Cont. ) • SAWS is moving from “what weather will be” - which was focused on forecasting weather based Hazard only to “what the weather would do” - which is designed to express the expected impacts as a result of the expected weather. i. a. w assess danger of various sources of weather information in relation to local features (towns, roads, etc. ) 2020 -11 -28 Templ ref: PPT-ISO-colour. 001 Doc Ref no: 4

What Recent Literature Says • Frequency of heavy precipitation is likely to increase (IPCC report, 2012; Seneviratne, 2012) • Flash-floods (FFs) are often a hydrometeorological problem (e. g. ; Poolman, 2014) • FFs are rated in the top two natural disasters across the globe (Grabs, 2010) • FFs result in significant economic losses (e. g. ; infrastructure damage; loss of agricultural outputs human fatalities; and so on) (Gaume et. al, 2009) 2020 -11 -28 Templ ref: PPT-ISO-colour. 001 Doc Ref no: 5

Region of Interest • The Vhembe and Mopani district municipalities are our area of interest situated over the north-eastern parts of the country. • The area is predominatly rural, an agricultural and tourisim hub. • The main economic sector being the mining, community services and finance. 2020 -11 -28 Templ ref: PPT-ISO-colour. 001 Doc Ref no: 6

NWP Model Suggestions: GFS Observations at 12: 00 UTC 2020 -11 -28 Templ ref: PPT-ISO-colour. 001 Doc Ref no: 7

Discussion of Potential Weather - defined upper trough (black isobars) along the west coast deepened the surface trough (white isobars) over the west-central interior of the South Africa (RSA) - The upper also sent perturbations on the central and eastern provinces of the RSA - tropical low developed over southern Mozambique NB: SST estimates ranged between 28 and 32 OC to the south of the Mozambique Channel (e. g. ; Passage Weather website) - The tropical low was anticipated to cause advection of anomalously warm and highly unstable moist air onto the north-eastern region - Thunderstorm with heavy rain was likely in the north-eastern corner 2020 -11 -28 Templ ref: PPT-ISO-colour. 001 Doc Ref no: 8

NWP Model Suggestions: UM • UM accumulated rainfall between 00: 00 to 24: 00 UTC 9 on 13 th Feb 2019 • 100 to over 300 mm suggested (Red circle) No Rain 2020 -11 -28 • No rain suggested (Blue Circle) Templ ref: PPT-ISO-colour. 001 Doc Ref no: 9

Analyses From Observations (Surface Network + Satellite) 2020 -11 -28 Templ ref: PPT-ISO-colour. 001 Doc Ref no: 10

SMS Warnings (Sat. images + Rainfall Accumulation) 13 February 2019 @ 12: 00 Z 13 Feb 2019 @ 15: 00 Z Warning: 13/02/2019 15 h 00 TO: 14/02/2019 19 h 00 Severe Thunderstorms - observed moving into the Ba-Phalaborwa LM of Limpopo (east of Phalaborwa town) with damaging winds, large hail and heavy rain leading to localized flooding moving slowly west and north -west. . SAWS 2020 -11 -28 Templ ref: PPT-ISO-colour. 001 Doc Ref no: 11

SMS Warnings (Cont. ) (Sat. images + Rainfall Accumulation) Watch: 13/02/2019 22 h 00 TO: 14/02/2019 19 h 00 Flooding - expected in places over the Mopani and Vhembe Districts of Limpopo overnight tonight into tomorrow (Thursday). . SAWS 13 February 2019 @ 18: 00 Z 2020 -11 -28 Templ ref: PPT-ISO-colour. 001 Doc Ref no: 12

SMS Warnings (Cont. ) (Sat. images + Rainfall Accumulation) 13 February 2019 @ 21: 00 Z Warning: 13/02/2019 21 h 00 TO: 14/02/2019 02 h 00 Severe Thunderstorms - are observed in the Limpopo river valley(Musina, Mutale and Thulamela LMs), resulting in strong damaging winds and localized flooding due to heavy downpours. SAWS 2020 -11 -28 Templ ref: PPT-ISO-colour. 001 Doc Ref no: 13

SMS Warnings (Cont. ) (Sat. images + Rainfall Accumulation) • Watch: 14/02/2019 01 h 00 TO: 15/02/2019 06 h 00 Flooding- expected in places over the Mopani and Vhembe Districts of Limpopo today into Friday morning. . SAWS • Warning: 14/02/2019 08 h 00 TO: 15/02/2019 00 h 00 Heavy rain- leading to localised flooding is expected in places over the Vhembe, Blouberg in Capricorn District Municipalities of the Limpopo Province. . SAWS 2020 -11 -28 Templ ref: PPT-ISO-colour. 001 Doc Ref no: 14

Impact-based Warning System 2020 -11 -28 Templ ref: PPT-ISO-colour. 001 Doc Ref no: 15

Impact-based Warning System (Cont. ) 2020 -11 -28 Templ ref: PPT-ISO-colour. 001 Doc Ref no: 16

Impacts on the Ground Heavy flooding at Thavhani Mall - Valentines plans were most likely cancelled) 2020 -11 -28 Templ ref: PPT-ISO-colour. 001 Doc Ref no: 17

Impacts on the Ground PSL match between Black Leopards and Bidvest Wits was abandoned because of the heavy rainstorm; Leopard forfeited 1 -nil lead 2020 -11 -28 Templ ref: PPT-ISO-colour. 001 Doc Ref no: 18

2020 -11 -28 Templ ref: PPT-ISO-colour. 001 Doc Ref no: TSHIVHASIE TEA VENDA ROODEWAL BOS ARS TSHANOWA PRIMARY SCHOOL ELIM - HOSP MUKUMBANI TEA ESTATE - VENDA PUNDA MARIA EBENEZER DAM ARS MOTSEKETLA PRIMARY SCHOOL LEVUBU THOHOYANDOU WO TZANEEN-WESTFALIA ESTATE THOHOYANDOU AWS MODJADJI WATER PLANT THABINA DAM ARS TZANEEN DAM ARS GIYANI MODJADJI DAM ARS HAENERTSBURG ARS LETABA REST CAMP ARS TRICHARDTSDAL-SEKORORO HOSPITAL ARS TOURS DAM ARS MARA MAKHADO AIR FORCE BASE EILAND SPA ATKV -ARS KRUGERWILDTUIN SHANGONI ARS VENETIA MINE GRAVELOTTE ARS HOEDSPRUIT - MARULENG ARS GRAVELLOTE-RUBBERVALE ARS GIYANI - NSAMI DAM ARS OLIFANTS CAMP ARS HOEDSPRUIT AIR FORCE BASE Millimeters (mm) PHALABORWA - GRIETJIE ARS PHALABORWA GATE Observations: Rainfall Accumulation Rainfall data: 13 and 14 February 2019 225 200 175 150 125 100 75 50 25 13 th 0 14 th 19

Remarks • Potential severe thunderstorms were discussed in the morning for the eastern areas Mpumalanga and Limpopo • However, severe thunderstorms were withheld for review in the afternoon when more observations would have been collected • DRR responded with SMSes to disaster management; copied to social media (i. e. @SAweather. Servic & South African Weather Service) • SMS text does not take into account the expected impacts - hence the inadequate responses 2020 -11 -28 Templ ref: PPT-ISO-colour. 001 Doc Ref no: 20

Remarks (Cont. ) • A double job, with reasonable time lag, was carried out for the IBF explicit warnings • Nowcast and forecast warning were issued from mid-afternoon of 13 th February 2019 • IBF relays messages of greater relevance to enable those at risk to take appropriate action in other to avoid the adverse impact meteorological hazards. • Creating a weather SMART nations require the severe weather alerts that are PEOPLE-CENTERED 2020 -11 -28 Templ ref: PPT-ISO-colour. 001 Doc Ref no: 21

Conclusion • Creating a weather SMART nations require the severe weather alerts that are PEOPLE-CENTERED • After engaging with disaster management, a pilot phase was carried out, including running IBF parallel to the current warning system • IBF relays messages with greater details, prompting appropriate action in other to avoid the adverse effects of meteorological weather hazards. • IBF will be used exclusively from 1 May 2019 2020 -11 -28 Templ ref: PPT-ISO-colour. 001 Doc Ref no: 22

THANK YOU ? 2020 -11 -28 Templ ref: PPT-ISO-colour. 001 Doc Ref no: 23