####018002596#### AWUS01 KWNH 160636 FFGMPD NCZ000-161000- Mesoscale Precipitation Discussion 0455 NWS Weather Prediction Center College Park MD 236 AM EDT Mon Jun 16 2025 Areas affected...portions of north-central NC Concerning...Heavy rainfall...Flash flooding likely Valid 160635Z - 161000Z Summary...Locally considerable and life threatening flash flooding likely to continue for another few hours with additional 3"+ totals possible over areas that have had 3-6" of rainfall over past 3-6 hours. Discussion...Convection is tending to backbuild late overnight in the vicinity of a stalled front over portions of northeastern NC. The mesoscale environment is characterized by sufficient ML CAPE of 500-1000 J/kg, highly anomalous precipitable water values of 2.0-2.2" (near record levels, per GSO sounding climatology), and effective bulk shear of 20-25 kts. Moisture transport remains elevated from the W-WSW, nearly parallel to the deep layer (850-300 mb) steering flow (~20 kts), which is allowing for backbuilding from the Raleigh metro area eastward to Rocky Mount and Greenville. Some of these areas east of the Raleigh metro (which has been mostly dry so far) have picked up as much as 3-6" of rain over the past 3-6 hours. Flash flooding is already ongoing, the recent backbuilding trends (evident on both radar and infrared satellite imagery) may exacerbate or renew locally considerable flash flooding. While hi-res CAMs do not have a great handle on the situation (with both hourly HRRR and experimental RRFS runs struggling to properly initialize and model the ongoing storms), the 00z HREF does depict a concerning signal for significant additional accumulations (which is consistent with recent observational trends, especially considering locally wet antecedent conditions). The 00z NAM-nest solution in particular appears to be driving this HREF signal (as it depict localized totals as high as 4-7"), suggesting the potential for localized 3" and 5" exceedance (10-20% and near 10% odds, respectively, per 40-km neighborhood HREF exceedance probabilities). Isolated to scattered instances of flash flooding are likely, and locally considerable/life threatening flash flooding will be exacerbated with continued 1-3" hourly totals. Churchill ...Please see www.wpc.ncep.noaa.gov for graphic product... ATTN...WFO...AKQ...MHX...RAH...RNK... ATTN...RFC...ALR...NWC... LAT...LON 36277961 36267889 36057802 35997701 35637687 35247723 35447903 35927975 ####018001015#### PENA01 KWNH 161200 @UHPISF000CN MPDSUM@V2.0@0101700060@12160625@@0NMCGPHMPDQ@!' `' ` @ & B7)p&PNAM02@@!C~|||{~~~~~~@@C@@C@@8~~~}|||}}}|{{{z{z{{}~~~~@@@@@@7|{{zzzzzz{{{z{|{}|~||x@@@@@@0453 @@0454 @@C0455 @@d&MESOSCALE DISCUSSION SUMMARY GRAPHIC @@d& OF ALL VALID MESOSCALE DISCUSSIONS AT @@d& TIME OF PRODUCT CREATION:@@d& ISSUED 06/16/2025 0637Z @@ dNOAA/NWS/NCEP@@d WEATHER PREDICTION CENTER @@d FOR COLOR VERSION SEE: @@d WWW.WPC.NCEP.NOAA.GOV @