Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Fri Jan 12 2024 04:24:48 AWUS01 KWNH 120424 FFGMPD TNZ000-ILZ000-MOZ000-ARZ000-OKZ000-121023- Mesoscale Precipitation Discussion 0010 NWS Weather Prediction Center College Park MD 1124 PM EST Thu Jan 11 2024 Areas affected...Central/Northern AR...Southern MO Concerning...Heavy rainfall...Flash flooding possible Valid 120423Z - 121023Z SUMMARY...Areas of heavy showers and thunderstorms which will be capable of occasionally training over the same area may result in isolated instances of flash flooding. The main areas of concern will be for central and northern AR into southern MO. DISCUSSION...Strengthening warm air advection and moisture transport out ahead of an amplifying upper-level trough and associated cold front over the central and southern Plains will continue to facilitate the development and expansion of heavy shower and thunderstorm activity heading through the overnight hours. The area VWP data shows a convergent south-southwest low-level jet on the order of 40 to 60+ kts nosing up across the Lower MS Valley, and this coupled with a pool of at least modest elevated instability with MUCAPE values of locally over 1000+ J/kg is already leading to a fairly expansive area of convection across west-central to northern AR, with some activity also developing farther north over southern MO in the warm air advection regime. Shear profiles are quite strong with as much as 50 to 60+ kts of effective bulk shear in place across eastern OK and through much of central and western AR, and the 3-hour MUCAPE differentials are as much as +400 to +800 J/kg across much of this region which is coinciding with the rapid convective cloud top cooling that has been ensuing over the last couple of hours as stronger and more organized updrafts materialize. Heading through the overnight hours, heavy showers and thunderstorms will tend to further expand in coverage off to the northeast with areas of central to northern AR and southern MO gradually getting into a more organized threat for heavy rainfall. The convection may become aligned sufficiently parallel with the deeper layer southwest flow to foster some occasional bands of training convection, and this will yield at least some concern for excessive rainfall totals. The CIRA-LVT data is showing increasingly strong moisture transport in the SFC-850mb layer and is reflective of the strengthening low-level jet. This combined with the destabilizing low-level environment should yield an increase in rainfall rates that may reach upwards of 1.5 inches/hour with the stronger convective cores. This is supported by the 00Z HREF and recent runs of the experimental WoFS data. Assuming at least some localized pockets of cell-training, some rainfall totals by late tonight may reach as high 3 to 4 inches which may result in some isolated instances of flash flooding, with the urban areas at greatest risk. Orrison ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!5o-1BjfOgqEplJl5dZDNQmaVhcwzp_qc5H2vYaF4H44K0u-603KE9vii1zNHns7PxzQv= qx0O7HcS4ywBisPStMcoHtk$ for graphic product... ATTN...WFO...LSX...LZK...MEG...PAH...SGF...SHV...TSA... ATTN...RFC...ABRFC...LMRFC...MBRFC...NCRFC...NWC... LAT...LON 38009141 37939019 37298934 36298964 35539023=20 34319209 33999362 34339401 34889366 35289350=20 35619380 35859446 36349467 37129430 37769283=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) .