After the latest model update, we have decided to issue a severe weather warning. The main threat appears to be from one or two strong thunderstorms. The warning is valid from 14:00 on Tuesday 10/09 till noon on Wednesday 11/09 unless otherwise indicated.

An area of low pressure over the Gulf of Gabes will push an unstable air mass towards the central Mediterranean. Upon coming into contact with the warm sea around us, this unstable air mass will intensify and develop an area of showers and thunderstorms. Isolated showers are possible at any time till late on Wednesday 11/09. These could be heavy and thundery at times.

Atmospheric conditions will be favourable for the formation of organised convective systems, particularly in the early hours of Wednesday 11/09. The warm sea locally will cause the area of showers and thunderstorms to reach peak activity over the sea between Tunisia, Sicily and the Maltese Islands. One or two thunderstorms may affect the Maltese Islands. Expect heavy to torrential rainfall, very strong winds and hail for some time in the event of a direct hit. At least one of the thunderstorms could be severe. A thunderstorm qualifies as severe if at least one of the following is observed: winds of at least Force 8, hailstones of at least 2 cm diameter or the occurrence of funnels. In the event of the thunderstorm missing us, total rainfall will be in the region of 2.5 mm to 10 mm. In the event of thunderstorms affecting us, total rainfall may exceed 30 mm. Further detailed updates will be issued ahead of any thunderstorms.

The situation will improve substantially in the afternoon on Wednesday 11/09. The sky should clear up. The East Northeast wind will remain strong, however, reaching Force 5/6 at times. In the meantime, isolated showers are possible at any time.

 

Wara l-aħħar aġġornament tal-mapep, iddeċidejn li noħorġu twissija ta’ maltemp. It-theddida mill-maltemp jidher li se tkun l-aktar fil-forma ta’ xi żewġ maltempati qawwijin. Din it-twissija se tkun fis-seħħ minn 14:00 tat-Tlieta 10/09 sa nofsinhar ta’ l-Erbgħa 11/09, sakemm ma jkunx indikat mod ieħor.

Firxa ta’ pressjoni baxxa fuq il-Golf ta’ Gabes se timbotta massa ta’ arja instabbli lejn iċ-ċentru tal-Mediterran. Hekk kif tiġi f’kuntatt mal-baħar sħun li hawn madwarna, din il-massa ta’ arja instabbli se tkun qed tintensifika u mistennija tiżviluppa diversi ħalbiet tax-xita u maltempati bir-ragħad. Ħalbiet iżolati tax-xita huma possibbli l-ħin kollu sa tard l-Erbgħa 11/09. Dawn jistgħu jkunu qawwijin u bir-ragħad għal ftit ħin.

Is-sitwazzjoni atmosferika se tkun qed tiffavorixxi l-iżvilupp ta’ sistemi konvettivi organiżżati, speċjalment fis-siegħat bikrija ta’ l-Erbgħa 11/09. Il-baħar sħun madwarna se jwassal biex il-ħalbiet tax-xita u maltempati bir-ragħad jilħqu l-aqwa tagħhom fuq il-baħar bejn it-Tuneżija, Sqallija u l-Gżejjer Maltin. Sa żewġ maltempati jistgħu jaħkmu lill-Gżejjer Maltin. Stennew xita qawwija jew torrenzjali, riħ qawwi ħafna u silġ għal xi ħin jekk tmissna xi maltempata. Minn ta’ l-anqas maltempata waħda tista tkun severa. Biex maltempata tikkwalifika bħala severa jrid ikollha minn ta’ l-anqas waħda minn dawn: buffuri b’qawwa ta’ Forza 8, silġ b’daqs ta’ 2 cm jew il-formazzjoni ta’ xi tromba. Jekk il-maltempata taqbiżna stennew minn 2.5 mm sa 10 mm ta’ xita. Jekk il-maltempata tolqotna, it-total ta’ xita jaf jaqbeż it-30 mm. Aktar dettalji se jsegwu qabel maltempati bir-ragħad.

Is-sitwazzjoni se taqleb għal aħjar wara nofsinhar ta’ l-Erbgħa 11/09. Is-sema għandu jibnazza. Minkejja dan, ir-riħ mill-Grieg il-Lvant xorta waħda se jibqa qawwi. Dan se jlaħħaq Forza 5/6 kultant. Sadattant, ħalbiet iżolati tax-xita huma possibbli minn ħin għal ieħor.