Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Fri Jan 17 2025 19:52:40 ACUS01 KWNS 171952 SWODY1 SPC AC 171950 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0150 PM CST Fri Jan 17 2025 Valid 172000Z - 181200Z ....NO SEVERE THUNDERSTORM AREAS FORECAST... ....SUMMARY... Isolated thunderstorms are possible from eastern Oklahoma into the Lower Mississippi/Tennessee Valleys and central Gulf Coast region this afternoon into early Saturday morning. ....20z Update... The previous forecast generally remains on track with only minor adjustments needed to the thunder line to reflect recent convective trends across central OK and trends in recent guidance. ....Central/Eastern OK... Sporadic lightning flashes have been noted across southwest to central OK over the past few hours - likely the result of strong synoptic ascent/mid-level cooling within the left-exit region of the upper jet over central TX (which is also evident by steady surface pressure falls across OK/KS). Occasional lightning flashes will remain possible through late afternoon and the evening hours as this activity spreads east/northeast into AR and far southern MO. ....Eastern AL/far western GA... Recent HRRR solutions continue to suggest a slight increase in coverage of weak thunderstorms during the 10-12 UTC period early Friday morning across far eastern AL. Forecast soundings from other guidance seem to corroborate this trend with 100-250 J/kg MUCAPE spreading into far western GA during this period. Given the convective signal and favorable environment, the thunder line was shifted east to account for low-end, early-morning thunderstorm potential. ...Moore.. 01/17/2025 ..PREV DISCUSSION... /ISSUED 1028 AM CST Fri Jan 17 2025/ ....Synopsis... Satellite imagery shows a well-defined shortwave trough moving through the southern High Plains, with another shortwave visible farther southwest in the vicinity of the northern Baja Peninsula. An extensive fetch of westerly/southwesterly flow aloft exists throughout the bases of these waves, extending from the Baja Peninsula into the southern Plains. The northern shortwave is forecast to continue eastward across OK/north TX throughout the day. As it does, the flow aloft will strengthen to 90-110 kt over TX before spreading eastward/northeastward into the Lower MS Valley this evening and overnight. Recent surface analysis reveals a developing low near the KS/CO/OK border intersection, along the southern periphery of the surface troughing that extends across the central Plains. This low is expected to solidify over the next several hours as it moves along the Red River, with its adjacent warm sector shifting eastward as well. ....Eastern OK into AR... Persistent warm-air advection ahead of the approaching shortwave trough and attendant surface low may result in enough mid-level moistening to support a few elevated thunderstorms during the afternoon/early evening. Given the weak instability (i.e. MUCAPE less than 250 J/kg) and elevated nature of any convection that can form, severe storms are not expected. ....MS/AL... Strengthening warm-air advection is anticipated this evening and overnight across the Southeast as shortwave trough continues eastward and the strong jet max mentioned into the synopsis spreads into the region. This should promote an increase in buoyancy, with a resulting increase in thunderstorm coverage. Even so, low-level stability is expected to persist, with all of the buoyancy above 900-850mb. Strong vertical shear could result in a few more organized updrafts capable of producing small hail. However, elevated character to the thunderstorms and generally modest buoyancy (i.e. MUCAPE at and below 500 J/kg) should limit the overall severe potential. $$ = = = 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) .