BBS: TELESC.NET.BR Assunto: HVYRAIN: Excessive Rainfall Discussion De: COD Weather Processor Data: Sun, 24 May 2026 08:16:03 +0000 ----------------------------------------------------------- FOUS30 KWBC 240815 QPFERD Excessive Rainfall Discussion NWS Weather Prediction Center College Park MD 415 AM EDT Sun May 24 2026 Day 1 Valid 12Z Sun May 24 2026 - 12Z Mon May 25 2026 ...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM THE CENTRAL GULF COAST INTO NORTH GEORGIA AND ACROSS THE UPPER OHIO VALLEY... The well defined MCV moving from southeast LA into far southern MS early this morning expected to continue to push northward day 1 across central AL and into north GA. While the organized convection associated with this MCV may weaken early day 1, there is potential for convection to re-fire ahead of this MCV later this afternoon=20 in the axis of much above average PW values, 2 to 2.5+ standard=20 deviations above the mean expected to stretch from the Central Gulf Coast, northeastward through the Southern to Central Appalachians, Southeast and Mid-Atlantic. We added a slight risk from central AL into north GA to account for this convective potential. Farther to the southwest...we made some significant changes to the previous slight risk area across southern MS and southern LA. We=20 suppressed the slight, keeping it just for far southeast LA. The=20 best instability in the wake of the northeastward moving MCV will=20 be over the northern Gulf, suggesting the heaviest precip with the=20 next round of convection also being offshore. We kept the New=20 Orleans metro area in the slight as model consensus is for a narrow axis of heavy rains to extend into far eastern LA. Across FL...the marginal risk was extended south into portions of north central to southwest FL. Model consensus is for another round of active convection forming Sunday afternoon in a general north to south axis. Slow moving cells will again have potential for produce locally heavy rainfall amounts and isolated runoff issues. There will be potential for overlap of yesterday's heavy rainfall amounts with Sunday afternoon's. The biggest runoff threat will continue to=20 be in more urbanized regions. Over the Upper Ohio Valley...added a slight risk area from northeast KY into eastern OH, northwest WV and far southwest PA. Both the HREF and RRFS are showing fairly high probabilities, 25-50%+ for 3 hour precip amounts exceeding FFG values this afternoon into early evening. Favorable right entrance region jet dynamics in the above mentioned axis of anomalous PW values will support potential for heavy precip and localized runoff issues. Oravec Day 2 Valid 12Z Mon May 25 2026 - 12Z Tue May 26 2026 ...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM THE CENTRAL GULF COAST TOWARD THE SOUTHERN APPALACHIANS... An axis of anomalous PW values, 2 to 2.5+ standard deviations=20 above the mean, will persist from the Central Gulf Coast,=20 northeastward across the South, Southeast and Southern Mid-Atlantic day 2. The closed low over the eastern portions of the Southern=20 Plains toward the Lower MS Valley will move only very slowly north=20 northeastward day 2, keeping a favorable broadly upper diffluent=20 pattern to its east in this anomalous PW axis. This will support=20 widespread scattered convection and potential for widespread=20 moderate to heavy precip totals. There is a typical amount of model qpf spread, but consensus for potential for widespread moderate to heavy totals. There will likely be overlap between the day 1 and=20 day 2 heavy precip areas, although low confidence at the moment=20 with details. No significant changes made to the previous outlooks=20 areas. Minor adjustments made to fit the latest model qpf=20 consensus. Oravec Day 3 Valid 12Z Tue May 26 2026 - 12Z Wed May 27 2026 ...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM THE CENTRAL GULF COAST TOWARD THE SOUTHERN APPALACHIANS AND ACROSS THE SOUTH=20 CENTRAL TEXAS... Not a lot of changes to the wet pattern from the Central Gulf Coast, northeastward across the South, Southeast and Southern Appalachians. The axis of anomalous PW values, 2 to 2.5+ standard deviations above the mean, will persist across this area in a region of persistent south southwesterly mid to upper level flow on the east side of the weak mid to upper low moving north through the Lower MS Valley. Expect another day of widespread scattered convection and widespread moderate to heavy rainfall totals. With not much changes overall to the large scale pattern, a slight risk was maintained in a similar region as during the day 2 period. There may again be overlap in heavy rain areas day 3 with day 1 and 2, which may lead to a upgrade in threat categories in future issuancs. Mid to upper level troffing developing across the Southwest during day 2 will be pushing height falls into the Southern Plains day 3. Increasingly active convection likely across the Southern Plains day 3, with model consensus for widespread moderate to heavy totals. Not a lot of changes made to the previous slight risk area over south central TX. This region has seen several rounds of heavy precip over the past week, lowering FFG values and increasing threat of additional runoff issues. There is a lot of spread with qpf details, but a strong signal for heavy rainfall totals day 3 across this area. Oravec Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!4jJlhDsNQjMJqUm2nsMGnvX7UqlG3__yioIrLLz_tTI3= vpWwll0tSPkoJNuXNAJ9FYnM8OhBnebKAJle2t01KjpRrb4$=20 Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!4jJlhDsNQjMJqUm2nsMGnvX7UqlG3__yioIrLLz_tTI3= vpWwll0tSPkoJNuXNAJ9FYnM8OhBnebKAJle2t01nlxtFAU$=20 Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!4jJlhDsNQjMJqUm2nsMGnvX7UqlG3__yioIrLLz_tTI3= vpWwll0tSPkoJNuXNAJ9FYnM8OhBnebKAJle2t010rEsBPo$=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]