BBS: TELESC.NET.BR Assunto: HVYRAIN: Excessive Rainfall Discussion De: COD Weather Processor Data: Sat, 9 May 2026 08:00:24 +0000 ----------------------------------------------------------- FOUS30 KWBC 090800 QPFERD Excessive Rainfall Discussion NWS Weather Prediction Center College Park MD 400 AM EDT Sat May 9 2026 Day 1 Valid 12Z Sat May 09 2026 - 12Z Sun May 10 2026 ...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF=20 SOUTHERN LOUISIANA AND SOUTHERN MISSISSIPPI... A Slight Risk remains centered over southern Louisiana and southern Mississippi, where a highly sensitive environment exists following significant flash flooding yesterday.=20 Short-term hi-res guidance suggests convection currently=20 developing over northern Louisiana will track southward into the=20 risk area later this morning. These clusters are expected to=20 intensify as they encounter deeper moisture (PWs at or 1.75=20 inches) and favorable mid-to-upper level support, including mid- level shortwave and upper-level jet dynamics. Water vapor imagery=20 reveals a well-defined shortwave currently traversing western=20 Texas, which is forecast to continue eastward, reaching the Texas=20 Coast by this evening. Additional storm development is possible=20 later in the day as this feature interacts with lingering deep=20 moisture. Given that 3-hr FFGs remain under an inch in some=20 locations due to antecedent saturation, any additional heavy rain=20 is likely to pose a flash flooding threat. The HREF shows a robust signal for additional totals exceeding 2 inches over these=20 vulnerable areas today. Farther east, a Marginal Risk was maintained from southern Alabama into the Florida Panhandle and southwestern Georgia. While antecedent conditions are drier, downstream propagation and the potential for training cells along an axis of deep moisture could lead to locally heavy totals and isolated flooding.=20 Pereira Day 2 Valid 12Z Sun May 10 2026 - 12Z Mon May 11 2026 ...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF THE SOUTHERN PLAINS AND THE LOWER MISSISSIPPI VALLEY... The forecast reasoning and outlook area remains largely consistent, with a Marginal Risk area extending from north-central Texas to southeastern Oklahoma, southern Arkansas, and northern Louisiana. A cold front dropping south through the Plains will become a primary focus for deepening moisture (PWs increasing to around 1.5 inches) and storm development. Synoptic support will strengthen as shortwave energy moves into the base of a broader-scale trough, placing the region within an area of strong ascent, supported by coupled upper-jet forcing. This combination of moisture and favorable dynamics, along with increasing instability, will promote broadening storm coverage by=20 the afternoon. While storms will eventually gain a more steady=20 southward progression, initial storm organization may be=20 characterized by slow movement and mergers. These factors combined=20 with the potential for high rainfall rates, support the=20 maintenance of the Marginal Risk for localized flash flooding.=20 Pereira Day 3 Valid 12Z Mon May 11 2026 - 12Z Tue May 12 2026 The probability of rainfall exceeding flash flood guidance is less than five percent. Pereira Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!79jAZUiO2ceG6F18MybIlcbxZMz58irqlCY-yZyO7KR3= n_9wkIhXuOyu45FmtnzNZDqx93VCbBKvv0SnqerLyZ9YX6k$=20 Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!79jAZUiO2ceG6F18MybIlcbxZMz58irqlCY-yZyO7KR3= n_9wkIhXuOyu45FmtnzNZDqx93VCbBKvv0SnqerLZ_L94Vo$=20 Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!79jAZUiO2ceG6F18MybIlcbxZMz58irqlCY-yZyO7KR3= n_9wkIhXuOyu45FmtnzNZDqx93VCbBKvv0SnqerLnYCwJUA$=20 =3D =3D =3D To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM. --- SBBSecho 3.28-Linux * Origin: Capitol City Online (1:2320/107) ----------------------------------------------------------- [Voltar]