Subj : DAY2SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Mon Oct 09 2023 17:09:16 ACUS02 KWNS 091709 SWODY2 SPC AC 091707 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1207 PM CDT Mon Oct 09 2023 Valid 101200Z - 111200Z ....NO SEVERE THUNDERSTORM AREAS FORECAST... ....SUMMARY... Severe thunderstorms are not expected on Tuesday. ....Synopsis and Discussion... A large, mature mid-latitude cyclone will be centered near the eastern Ontario/western Quebec border early Tuesday morning, and is forecast to remain largely in place throughout the period. Continental/off-shore low-level trajectories around this cyclone will keep low-level moisture limited across much eastern CONUS, precluding thunderstorm development. The only exception is across south FL the FL Keys, where ample low-level moisture and weak low-level convergence along a remnant frontal zone should support isolated thunderstorm development. Modest westerly flow aloft is expected across the central CONUS/Plains, contributing to a deepening of surface lee troughing across the High Plains. Some low-level moisture advection is anticipated across the central and southern Plains as a result, but warm low to mid-level temperatures should still preclude afternoon thunderstorm development across the majority of the region. The only exception is across the southern High Plains, where strong boundary-layer heating and convergence along the lee trough could be enough to overcome any inhibition. The low-level jet is expected to strengthen from the southern High Plains into the central Plains during the evening and overnight. Resultant warm-air advection will likely contribute to thunderstorm development over the Lower MO Valley vicinity. The region will be on the western edge of moderate mid-level flow, contributing to enough shear for a strong storm or two. Probability of severe is still too low to introduce probabilities. Thunderstorms are also possible Tuesday evening through Wednesday morning across south TX as the remnants of Tropical Cyclone Lidia approach the region. Highest chance for thunderstorms will remain offshore, but there will likely be enough buoyancy for a few thunderstorms over land, particularly early Wednesday morning. Farther west, a series of shortwave troughs, embedded within the cyclone flow around a deepening upper low, are forecast to move across the Pacific Northwest. The primary frontal band is expected early Tuesday morning, and some deeper convective cores are possible within this band. More cellular activity is anticipated in the wake of this band, before another band moves through late in the evening and overnight. A low-topped supercell or two is possible within the initial band, but largely veered low-level flow should keep any tornado risk very low. Isolated thunderstorms will be possible across parts of the northern Rockies as this shortwave continues northeastward through the day. ...Mosier.. 10/09/2023 $$ = = = 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) .