Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Thu Aug 31 2023 08:23:39 AWUS01 KWNH 310823 FFGMPD NCZ000-311400- Mesoscale Precipitation Discussion 1014 NWS Weather Prediction Center College Park MD 423 AM EDT Thu Aug 31 2023 Areas affected...eastern North Carolina Concerning...Heavy rainfall...Flash flooding likely Valid 310820Z - 311400Z Summary...Flash flooding is likely to continue in the short term across portions of eastern North Carolina, including the Outer Banks. Significant impacts from flash flooding will remain possible, though peak rainfall rates of 2-3 in/hr will gradually lower into the 1-2 in/hr range through 14Z. Discussion...08Z surface observations placed Tropical Storm Idalia just offshore of the southern North Carolina coast, with a brisk movement toward the northeast. Trends in infrared satellite imagery showed the coldest cloud tops over far eastern North Carolina, racing northeastward. Since 05Z, rainfall rates greater than 1 in/hr have been located within about 50 miles of the North Carolina coast with the highest rainfall rates occurring along the coast from near North Topsail Beach to the Outer Banks, south of Hatteras. It is along the coast where two distinct feeder bands have been interacting with a coastal front, with mini supercells in the vicinity of Hatteras at 0730Z, supporting slow moving and repeating rounds of heavy rain. Observed rainfall totals of 3-4 inches in 2 hours have occurred along the coast along with areas of ongoing flash flooding. Over the next 6 hours, Idalia is expected to begin more of an eastward translation, continuing to focus the greatest low level convergence near the Outer Banks, co-located with the greatest instability of an estimated 500 to 1000+ J/kg MLCAPE (08Z SPC mesoanalysis). After roughly 12Z, rainfall rates are expected to fall below 2 in/hr as Idalia begins to move father away from the coast. However, in the short term, continued rainfall rates of 2-4 inches in about 2 hours time will support rapid rises and exacerbate any ongoing areas of flooding. Additional rainfall totals of 3-6 inches are expected through 14Z, continuing the likely threat for additional flash flooding, with significant impacts remaining possible prior to Idalia departing farther offshore. Otto ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!9eji29U-RMW77sgzxkgVAzb5yzWlVv4PcFSRAN1A8x-NsBJveaAy-7SUYY7tFEbrEyBe= 3LWOJnvmo2igShEcbLmXy0s$ for graphic product... ATTN...WFO...AKQ...ILM...MHX...RAH... ATTN...RFC...SERFC...NWC... LAT...LON 36157575 36117512 35777481 35067474 34577543=20 33987685 33797785 33987827 34717879 35867717=20 =20=20=20=20=20=20=20=20=20=20=20=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 3.14-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .