Issued: 12am on Thursday, January 1st 1970
Technical Forecast Discussion
Short Term (Wednesday 7/24 through Saturday 7/27)
As of Wednesday evening, much of the region including Southeast Ohio is still influenced by an upper level trough, but within the weak downstream flow of it. In association, high pressure of about 1022mb is situated near the state of Illinois with future propagation eastward. N’ly to NE’ly flow will continue to exist through Thursday, which will keep the layers of the atmosphere relatively dry with temperatures slightly below average. Although, the weather conditions look to remain consistently dry, chances of patchy fog formation will endure through the early morning hours of this forecast period. This combination of the diurnal heating throughout the day, strong radiational cooling at night and calm wind flow will aid in decoupling of the surface boundary for the lowlands and valleys. This higher pressure is projected to push further eastward nearing the east coast by Friday, which will help shift our winds and aid a more southerly flow. This influx of lower-level moisture will allow dewpoints to be on the rise through Friday and into the long term with values in the low-mid 60s. Alongside the dewpoints, the high temperatures will begin to increase into the mid-upper 80s, which will create another hot and humid setup. Near the end of the forecast period, another upper trough looks to slide eastward across the northern Great Lakes region, but will have little to no impacts for southeast Ohio. This battling high pressure will remain just south of the region alongside this weak upper level flow. With an increase in WAA and moisture, the chance for some passing clouds and/or a pop-up shower Saturday and late weekend cannot be ruled out. The Jet Stream looks to remain active as another upper trough and associated surface front will affect the region early next week.
Long Term (Sunday 7/28 through Tuesday 7/30)
High pressure continues to hold through for Sunday and the first half of Monday in maintaining mostly sunny and drier conditions. Cloud cover will thicken as the troposphere’s layers begin to moisten late Monday. A shortwave trough with weak flow aloft lifts northeasterly across the Great Lakes on Tuesday. This associated disturbance will drop a cold frontal boundary from the north late Tuesday that will slowly stall out across the region. Instability and vertical parameters remain not concerning for the end of the period, which will likely result in rain showers as the primary outcome. Out ahead of the cold front there is a slight possibility for prefrontal rain showers late evening and overnight on Monday. The cold front approaches by late Tuesday and stalls out along southern Ohio, extending the chances for rain and even thunderstorms through Wednesday and Thursday. Dewpoints will rise into the mid-upper 60s whereas temperatures will slightly decrease into the low 80s with this increase in cloud cover and rain potential.