Mesoscale Discussion 1646
Issued: · Valid: –
Summary
Severe storms capable of producing damaging winds may develop across the lower Great Lakes vicinity early this afternoon.
Product Text
000 ACUS11 KWNS 181618 SWOMCD SPC MCD 181618 NYZ000-PAZ000-WVZ000-OHZ000-181815- Mesoscale Discussion 1646 NWS Storm Prediction Center Norman OK 1118 AM CDT Sat Jul 18 2026 Areas affected...Lower Great Lakes Vicinity Concerning...Severe potential...Watch possible Valid 181618Z - 181815Z Probability of Watch Issuance...60 percent SUMMARY...Storm intensification is possible early this afternoon. Wind damage will be the main risk in the short term. A watch may become necessary depending on trends in downstream destabilization. DISCUSSION...Convection has developed near the southern shores of Lakes Erie/Ontario. This activity is in relatively close proximity to the upper-level shortwave trough now moving into Lower Michigan. Temperatures in western/central New York have struggled to warm significantly due to earlier precipitation and cloud cover. Farther southwest, temperatures have already risen into the mid/upper 80s F. While storms could potentially produce damaging winds as temperatures continue to warm into the afternoon, the downstream environment is not currently very favorable. It is probable that it will take a few more hours of heating before a more organized severe threat can develop along the synoptic cold front. Trends in storm coverage/intensity will need to be monitored. Timing for a possible watch is the main uncertainty at this time. ..Wendt/Thompson.. 07/18/2026 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...BGM...BUF...CTP...PBZ...CLE... LAT...LON 43467733 43347687 43017673 41757787 40937927 40597980 40478060 40458129 40608172 40958183 41578133 41868096 42607931 43317865 43487804 43467733 MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN