Flash Flood Guidance
Issued by NWS
Issued by NWS
084 AWUS01 KWNH 172031 FFGMPD VAZ000-NCZ000-TNZ000-180130- Mesoscale Precipitation Discussion 1030 NWS Weather Prediction Center College Park MD 431 PM EDT Tue Sep 17 2024 Areas affected...Piedmont to Southern Blue Ridge Concerning...Heavy rainfall...Flash flooding likely Valid 172027Z - 180130Z SUMMARY...East to West training and efficient rainfall rates up to 2-3"/hr in a band developing over an occluded front over the Piedmont of northern North Carolina will continue to develop and shift across portions of the southern Blue Ridge near the NC/VA border into this evening. Localized flash flooding/rapid inundation flooding in this narrow corridor is likely. DISCUSSION...Convection has reinvigorated in broad convergence along/north of an occluded front over the NC Piedmont this afternoon from around the Raleigh-Durham Triangle west through the southern Blue Ridge near the NC/VA border. Dewpoints in the low 70s with sufficient instability (1000 J/kg MUCAPE) along the occluded front are fueling stronger updrafts and the influx of tropical moisture is allowing redevelopment. PW of 1.6 to 1.8" are 1.5 sigma from normal support 2-2.5"/hr rain rates that may locally peak at 3"/hr as seen from KFCX over Stokes Co NC, particularly in areas of upslope with the steep eastern side of the Blue Ridge (near and south of Fancy Gap) in the area of concern. Slow motion to the occluded low/front will support west to east training over the next few hours. This may result in 3-5" localized totals over the NC Piedmont and especially along the Blue Ridge. Given that around an inch of rain fall in advance of this activity over the past day, FFG is generally around 1.5"/hr. Recent HRRR runs have picked up on this activity and features splotches around 2" through 02Z. However, given the sufficient instability, slow motion, and heavy rates observed, flash flooding is considered likely. Jackson ...Please see www.wpc.ncep.noaa.gov for graphic product... ATTN...WFO...MRX...RAH...RNK... ATTN...RFC...LMRFC...OHRFC...SERFC...NWC... LAT...LON 36938152 36838049 36647977 36337900 36057852 35827844 35757878 36218049 36398181