Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CDT Mon Oct 20 2025 Valid 231200Z - 281200Z ...DISCUSSION... Severe storm potential is likely to increase through the extended forecast period as a series of upper troughs and enhanced southwesterly flow aloft return to the central and southeastern CONUS. The primary uncertainty remains the degree of moisture return and instability. ...D4/Thursday-D6/Saturday Southern Plains/ArkLaTex... A shortwave trough will cross the southern Rockies into the High Plains supporting lee cyclogenesis Thursday and Thursday night. In the wake of the earlier frontal passage, modest low-level moisture return is expected to take place east of the low and a lee trough over the southern Plains as a warm front lifts northward. Cooling mid-level temperatures will allow for diurnal destabilization and some organized severe potential as westerly flow aloft also increases. Strong to potentially severe storms are possible D4/Thursday and D5/Friday in vicinity of the surface low and warm front across KS/OK, and along the lee trough into the TX Panhandle. However, confidence in the overall severe risk and its evolution is low, pending sufficient moisture return and the timing of the upper trough. Some severe potential will likely shift eastward into the ArklaTex D6/Saturday as the upper low moves eastward and low-level moisture return continues. Confidence in the severe risk is limited, owing to the potential for several prior days of convection. ...Eastern Plains and Mid MS Valley D7-D8... Greater severe potential may develop towards the end of the extended forecast period as a deep upper trough matures over the Plains D7/Sunday and moves into the Midwest/MS Valley D8/Monday. Ensemble and deterministic guidance show a strong cold front and low with sufficient moisture/instability for severe storms capable of all hazards from the eastern Plains and MS Valley late this weekend into early next week. 15% severe probabilities could be needed in future outlook cycles should model solutions converge on timing and location of the greatest severe risk.
