


Flash Flood Guidance
Issued by NWS
Issued by NWS
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031 AWUS01 KWNH 021937 FFGMPD MSZ000-LAZ000-030100- Mesoscale Precipitation Discussion 0853 NWS Weather Prediction Center College Park MD 336 PM EDT Sat Aug 02 2025 Areas affected...Central Louisiana... Concerning...Heavy rainfall...Flash flooding possible Valid 021935Z - 030100Z SUMMARY...Slow moving, efficient thunderstorms with potential of favorable propagation for some repeating/training. Rates of 2-2.5"/hr and localized totals of 3-4" may result in localized rapid inundation flooding. DISCUSSION...GOES-E WV suite shows a weak/elongated shortwave feature along the southwest edge of the northern stream troughing across southwest AR into northeast Texas. This places the feature in the northeast quadrant of the synoptic ridge over TX and so flow becomes highly diffluent and weaker across central LA. Combine this with the mixed/worked over area affected by the complex across E TX this morning; there is a solid area of remaining high moisture/unstable air across much of LA into SW MS with total PWat values of 2.2-2.4 AND SBCAPEs over 2500-3000 J/kg for stronger, efficient thunderstorm development. This will support cells capable of intense instantaneous rates with localized 2-2.5"/hr totals scattered with the most intense cores to convection (as noted with initial round in north-central LA). Deep layer flow is weak and convergence is going to be generally driven by convective outflow propagation. As such, the older outflow boundary across E TX is also along/parallel to the deeper layer steering into the col east of the upper-level ridge. Initial convective development toward the northeast also helps to corral newer development along the I-49 corridor and should support slow but repeating environment to add overall totals toward the generally higher FFG values across the region. Given upstream weak surface convergence is further expanding convective initiation along the mean cell motion path... a few spots of 3-4" are becoming increasingly probable. Intersection with larger urban centers like Alexandria, Natchitoches and perhaps Layfette and Lake Charles toward 00z, late evening... will garner the greatest potential for possible rapid inundation flooding. Gallina ...Please see www.wpc.ncep.noaa.gov for graphic product... ATTN...WFO...JAN...LCH...LIX...SHV... ATTN...RFC...FWR...ORN...NWC... LAT...LON 32269379 32139299 32239249 32109197 31679165 30989135 30309146 30089198 30099293 30279342 31099346 31639372