1/17 – Brittany’s “Comfortable” Tuesday Evening Forecast
An upper low currently near the 4-Corners region will deepen as it crosses the southern portion of the Rocky Mountains. As this upper low moves across the Central Plains Wednesday and Wednesday night, a surface low will develop on the leeside of the Rockies and track right along with the upper low. Those features far proximity from the CWA means the strongest dynamics will mostly be north of the local area. Model soundings show low level shear to mostly be supportive of sub-severe with only 0-6km shear in a range that would promote supercell type storms. The other limiting factor is low level instability. Even in northwestern portions of the CWA, surface to 700mb CAPE is so minimal that it`ll be hard for robust updrafts to even develop. S CAMs are quite similar in timing with storms reaching western portions of the CWA just after 00z and reaching Jackson County MS close to sunrise Thursday. It should be noted that CAMs also show a steady weakening after midnight, which lines up will with decreasing instability and shear with time.
By this point in the forecast period, Thursday morning, closed low will be tracking eastward across the upper Mississippi River Valley crossing the Great Lakes Friday and exiting the East Coast Friday night. The cold front associated with the upper low moves through Thursday morning with only lingering showers in far eastern and southern portions of the CWA. A weak upper ridge will be sliding in right behind the low/trough but its moreso zonal flow along the Gulf Coast. That means there will be little opportunity for cooler temps to moderate Friday. The next system to potentially impact the CWA comes in later this weekend. At the moment, model solutions suggest a fairly complex pattern with 2 troughs tracking east across the country. Due to this, solutions vary quite a bit from model to model. The general consensus, however, is that it will be fairly rainy Saturday and possibly Sunday. The potential exists for heavy rainfall but uncertainty remains too high to state that with any confidence.