MD 0809 CONCERNING SEVERE POTENTIAL…WATCH POSSIBLE FOR NORTHERN ARKANSAS…SOUTHERN MISSOURI…FAR NORTHEAST OKLAHOMA
Mesoscale Discussion 0809 NWS Storm Prediction Center Norman OK 0911 AM CDT Fri May 16 2025 Areas affected...northern Arkansas...southern Missouri...far northeast Oklahoma Concerning...Severe potential...Watch possible Valid 161411Z - 161645Z Probability of Watch Issuance...60 percent SUMMARY...At least isolated supercells may develop over the next few hours, from far northeast Oklahoma into northern Arkansas and southern Missouri. Very large hail is likely with any development, and tornado risk will develop over time. DISCUSSION...Surface analysis and visible imagery clearly show a cold front extending from northwest TX into eastern OK and toward northwest MO, with a warm front rapidly pushing north across northern AR into southern MO. Satellite presentation across the warm sector indicates both a very moist air mass, with heating and mixing likely. The 12Z LZK sounding depicts the robust moisture and instability, with minimal real capping in place. As surface theta-e develops northward beneath the midlevel temperature gradient, and, the cold front pushes east into the heating air mass, at least isolated, early (midday) activity may develop given no cap, possibly as far west as OK. Some numerical guidance suggests this may occur, and this seem plausible. However, coverage of severe is a bit unclear this early in the day. At any rate, a conditional risk of very large, destructive hail exists. It also appears low-level SRH will remain sufficient during the day for a strong tornado risk, even as low-level winds gradually veer and reduce bulk values at or below 200 m2/s2. With such steep lapse rates and robust boundary layer moisture, intense updrafts should be more than enough to compensate for any marginal low-level shear. ..Jewell.. 05/16/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LZK...SGF...TSA... LAT...LON 35549240 35319480 35519540 36079508 36849465 37169450 37369303 37449195 37179153 36519122 35699156 35549240 MOST PROBABLE PEAK TORNADO INTENSITY...120-150 MPH MOST PROBABLE PEAK WIND GUST...65-80 MPH MOST PROBABLE PEAK HAIL SIZE...2.75-4.25 IN