Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Thu May 08 2025 20:33:31 AWUS01 KWNH 082033 FFGMPD MEZ000-MAZ000-NHZ000-RIZ000-VTZ000-CTZ000-NYZ000-NJZ000-PAZ000-090130- Mesoscale Precipitation Discussion 0243 NWS Weather Prediction Center College Park MD 432 PM EDT Thu May 08 2025 Areas affected...southern NY into southern/central New England Concerning...Heavy rainfall...Flash flooding possible Valid 082030Z - 090130Z Summary...Isolated to widely scattered areas of flash flooding will be possible across parts of southern NY into southern/central New England through late evening. Hourly rainfall of 1-2 inches with localized totals between 2 and 3 inches will be possible with activity likely diminishing in coverage and intensity after sunset. Discussion...20Z visible satellite and radar imagery showed scattered showers and thunderstorms in the vicinity of a wavy stationary front analyzed from coastal ME into southern NY/northern NJ. Earlier breaks in cloud cover and daytime heating have allowed for the development of weak instability (MLCAPE up to and locally in excess of 500 J/kg along the front over southern New England via SPC mesoanalysis). GPS data showed PWATs were modest, hovering near 1 inch but cell motions should be a bit slower, somewhere between 10-20 kt from the southwest. The coverage of showers and thunderstorms is expected to increase within the corridor between the front and a sea breeze boundary over southern CT into RI over the next couple of hours. The front is also forecast by the RAP to sweep southward, west of a surface low in east-central MA. Cell mergers, subsequent outflow and brief training with similar cell movement and boundary orientations could support a few spots with hourly rainfall between 1-2 inches and perhaps storm totals between 2 and 3 inches prior to expected dissipation after the loss of daytime heating. The expected total rainfall is certainly on the low side, but it may fall somewhat quickly atop a region of the Northeast which has seen 200 to 400+ percent of average rainfall over the past 7 days, leaving soil moisture values above average. This fact, combined with the urban nature of the region and rush hour could result in isolated to widely scattered instances of flash flooding over the next 3-5 hours. Otto ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!87id6Yox9IhGQA9HdHtf3d_vLLf1C6f81DsThCFm63wkFilMFkRxMEhyLrC0EKCFEKV9= 4GX2HSU5d-3iJR46ZAZywZ8$ for graphic product... ATTN...WFO...ALY...BGM...BOX...GYX...OKX...PHI... ATTN...RFC...MARFC...NERFC...NWC... LAT...LON 43377142 43217065 42647056 41757136 41257259=20 40927338 40577412 40657450 40757467 40967485=20 41227493 41747460 42637294=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 3.20-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .