There was one reported tornado yesterday near Granite Ledge, MN, a whopping 180 miles from my target area. I saw late last evening that there was a line of severe thunderstorms farther to the northeast; the line was the remnants of these initial cells.
Today, the Storm Prediction Center has issued a See Text area for much of the country.
Of most interest in the See Text Area is the 2% Tornado Threat Ring to the east of Denver, CO.
None of the 12Z upper air soundings from the surrounding area look good. Denver, CO is too far west, North Platte, NE is too far north, and Dodge City, KS is heavily capped. Denver and North Platte both have good deep layer shear (48 kts and 58 kts, respectively).
The visible satellite image shows clear skies over Colorado, which will maximize the potential for daytime heating. There are some cloud streets that indicate moisture and shear over western Kansas and southwestern Nebraska.
The 12:45 Z surface observations show dewpoints into the upper 50s across the northeastern corner of Colorado.
The 850 mb NAM chart is not showing much temperature advection. There are wind vectors pointing across the gradient from warm to cold approaching from the south, which would indicate Warm Air Advection (WAA), but then there are also wind vectors pointing across another gradient from cold to warm, indicating Cold Air Advection (CAA), both of which are over northeastern Colorado. Because neither of these is strong (short wind vectors), I am not convinced either is occurring at an appreciable level. I should also point out that this is still using yesterday’s NAM run; today’s has not been posted.
The 700 mb NAM chart is showing a pocket of rising air in eastern Colorado. That is a good sign for storms. This is at least partially in response to the small amount of WAA occurring in this area.
The 500 mb NAM chart is showing little vorticity advection across the 2% Tornado Threat Ring area.
The 300 mb NAM chart shows some stronger upper level winds, though I hesitate to call that entire area a jetstreak. There is a steep trough to the west that may make the next few days interesting.
Overall, I’m not optimistic about storms today. If I were already chasing, I might hangout on the outskirts of Denver, thinking about drifting east as the cumulus field develops. Denver is too far west, and I may need to get a little bit north, perhaps along US-385.
I hope you enjoyed this post!
The Severe Weather Outlook is from the
Storm Prediction Center website. The satellite imagery is from the NOAA Satellite and Information Service.
The surface observation and upper level charts are from Unisys Weather.
High Plains Chasing 