[#NerdTweet] Mid-level shear impacting #Delta diagnosed from the GFS is currently ~30 kt in the 850-400 hPa layer, which is near double what the model predicted yesterday. This is responsible for Delta's currently discombobulated core structure. Last 7 runs valid 8:00pm EDT: pic.twitter.com/EKo7e4MRbs

— Dr. Levi Cowan (@TropicalTidbits) October 7, 2020