Flash Flood Guidance
Issued by NWS
Issued by NWS
832 AWUS01 KWNH 060053 FFGMPD NJZ000-PAZ000-DEZ000-MDZ000-060500- Mesoscale Precipitation Discussion 0402 NWS Weather Prediction Center College Park MD 853 PM EDT Wed Jun 05 2024 Areas affected...northern portions of MD...much of DE...southeastern PA...surrounding portions of NJ Concerning...Heavy rainfall...Flash flooding likely Valid 060050Z - 060500Z Summary...Rainfall rates of 1-3"/hr to continue for several more hours, shifting northeast from the Baltimore metro to the Philly metro. Localized instances of flash flooding are likely to continue (and some may be locally significant). Additional localized totals of 2-4" are possible. Discussion...A large cluster of showers and thunderstorms is progressing slowly northeastward across northern portions of MD, into DE, southeastern PA, and surrounding portions of NJ. This activity includes some embedded supercells along the southwestern flank of the cluster of storms, and these embedded supercells are producing rainfall rates of 1-3"/hr. The mesoscale environment is characterized by SB CAPE of 750-1250 J/kg, precipitable water values of 1.8-2.0" (near record values, per SPC sounding climatology), and effective bulk shear of 20-30 kts. Convection will continue to track generally towards the northeast with the mean low- to mid-level flow (though embedded supercells will favor a more easterly track), producing additional localized totals of 1-3". This will likely support localized instances of flash flooding across metropolitan areas along I-95, with the greatest concerns for metro areas where locally significant flash flooding is possible. Churchill ...Please see www.wpc.ncep.noaa.gov for graphic product... ATTN...WFO...CTP...LWX...PHI... ATTN...RFC...MARFC...NWC... LAT...LON 40927558 40777500 40237443 39617480 39417523 39167615 39037650 39327678 39867687 40547664