Issued: 12am on Thursday, January 1st 1970
Technical Forecast Discussion
Short term (Wednesday 8/8 through Saturday 8/11)
A cold front from the northwest will continue to approach the region this evening. Upper level models show a jet streak over Ohio maxing out around 80 knots. A small pocket of shearing was also present this afternoon, but has slowly faded. These ingredients allowed for the heavier showers the area received in the late afternoon. Precipitation will still be possible tonight as CAPE values around 1750 j/kg will be present until around 9/10pm. Rain is less likely to be as heavy since Southeast Ohio will sit in a area of lesser humidity tonight meaning moisture won’t be as abundant as it was today. High pressure will closely follow the cold frontal boundary as it pass over tonight before veering southwest Thursday. This will bring in drier conditions as downstream flow from a ridge begins to move over the region. This will result fair weather and higher temperatures in the mid 80s despite the recent cold front due to warm southern air being allowed to slowly filter north. Moisture ahead of of another approaching cold front will enter the region late Thursday, which will allow for a humid night with lows in the mid to high 60s. The cold front will enter the region on Friday afternoon as moisture continues to increase in the region. Showers will be more likely than storms as CAPE will be low, but positive vorticity will be available during peak heat time, so this is when storms will be most likely. Since diurnal heating will play a role in storm activity, chances for storms will decrease in the evening, but showers are still possible as moisture remains abundant in an atmosphere that has lift from vorticity. The new cold front will begin to turn stationary on Saturday around the same time a upper level trough becomes negatively tilted over the Great Lakes. Surface maps have the frontal boundary right over Southeast Ohio on Saturday. Disturbances at the mid level create another weak field of vorticity and CAPE. Precipitation is likely, but storms not so much since CAA on Saturday will lessen diurnal heating which looks to be the main forcing mechanism again.
Long term (Sunday 8/12 through Tuesday 8/14)
The deepening of the upper level trough allows for a low pressure system to form over eastern Ohio. This will allow for precipitation to continue in an environment that would of begun to be influenced by near by high pressure. Athens will be on the back end of the cold front, so conditions will be similar to Saturday. Storms will have a small chance to form since vorticity looks strong enough to provide lift, but Sunday will be another mild day with low 80 highs, so showers are expected to dominate. A closed upper-level low will be present in the region on Monday. Moisture from the low pressure system will remain in the region creating another environment conducive for precipitation. Once again, positive vorticity will be available, but CAPE will be weak. Since Monday looks to be another mild day, showers will be the main threat. While upper level disturbances will still be present on Tuesday, high pressure moves over Illinois allowing for a break from moisture and precipitation resulting in a mild and dry day.
The next technical discussion will be on Sunday 8/12