Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Mon Jan 23 2023 12:47:00 ACUS01 KWNS 231246 SWODY1 SPC AC 231245 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0645 AM CST Mon Jan 23 2023 Valid 231300Z - 241200Z ....NO SEVERE THUNDERSTORM AREAS FORECAST... ....SUMMARY... The risk for severe thunderstorms appears negligible across the U.S. today and through the overnight hours. ....Synopsis/Discussion... A prominently amplified, progressive mid/upper-level pattern will continue on shortwave to synoptic scales over the CONUS. A positively tilted trough is located from the lower Great Lakes, through a weak 500-mb low over OH, to parts of the Tennessee Valley region and Mid-South. This feature should move offshore from the Carolinas, Mid-Atlantic and New England around 00Z. The associated surface cold front -- analyzed at 11Z from a low near ACK southwestward across south-central FL near Lake Okeechobee -- should move southeastward across south FL through the afternoon. A narrow sliver of near-term 10% thunderstorm potential remains along/ahead of the frontal convective band now over the area. The prefrontal boundary layer across south FL will remain sufficiently moist to support deep convection (upper 60s to low 70s F surface dewpoints), but with some decrease in dewpoint values (mid 60s F) inland and on the East Coast, due to vertical mixing effects apparent in forecast soundings and the modified shallow moist layer of the 12Z MFL RAOB. Modest mid/upper-level lapse rates will persist, keeping peak MLCAPE mainly in the 500-800 J/kg range. Though deep/speed shear will be favorable (effective-shear magnitudes in the 40-55-kt range beneath the subtropical jet), lack of stronger buoyancy, low-level shear and lift will limit organization. Elsewhere, a compact, strong mid/upper-level cyclone was evident in moisture-channel imagery over western AZ, with a closed circulation extending as far as western parts of CO/NM and southwestern WY. The 500-mb low should pivot southeastward to near TUS by 00Z, then east-southeastward over the international border region to near ELP by 12Z tomorrow. A low-level cold front will precede this cyclone across northern MX, occasionally attached to a surface low as terrain conditions modulate flow and pressure perturbations ahead of the midlevel low. Associated mass response/lift and weak destabilization will support potential for isolated, sporadic lightning in the eastern sector the cyclone's cold core across parts of AZ, and tonight atop the elevated but increasingly unstable warm-advection/moisture-transport regime across parts of eastern NM and west TX. ...Edwards/Dean.. 01/23/2023 $$ = = = 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) .