... A cold front approaches tonight but stalls, lifting back to the north Saturday. Cold front Monday. High pressure middle of next week.
NEAR TERM /THROUGH SATURDAY/... As of 105 PM Friday...
Models show that a line of convection moving toward the area in Ohio and north central Kentucky should weaken considerably or dissipate. Additional convection is expected to form upstream this afternoon, providing the main focus for the weather tonight. With a decent low level jet and helicity values of 200-300 across Ohio and northern West Virginia, there is some concern that storms could produce damaging winds or possibly a tornado, regardless that they will generally be occurring after sunset. Models continue to struggle with the location and timing of these storms however. Models are also showing bullseyes of heavy rainfall across northern portions of the region. Again, models struggle with the exact location. Have added Greenup county in Kentucky and Lawrence county in Ohio to the Flash Flood Watch. Will continue to monitor the situation to see if any future adjustments need to be made based on where the convection forms.
Models continue to struggle on Saturday, as the location of tonight's weather will greatly affect Saturday's weather. Regardless, there should be an area of showers and thunderstorms moving across the area, with the best chances over Ohio and northern West Virginia closer to the frontal boundary.
SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/... As of 215 PM Friday...
The front is expected to continue to be stalled out to the north- northwest of the area as an upper level shortwave moves through, allowing for showers and thunderstorms to remain possible. Showers and storms will likely persist through Saturday night with the heaviest chances along the northern portion of the area. However, there is still quite a bit of uncertainty with how widespread and with the exact timing of these storms. Additional flooding issues will be possible Saturday night, particularly in any areas that already received heavy rainfall Friday night and Saturday.
For Sunday there is a marginal risk for severe weather clipping part of the southeast OH counties, but overall expecting storms to be relatively isolated and non-severe. However, with the rain received earlier in the weekend, could have potential flooding issues if any thunderstorms move over an area that was already hit previously this weekend, but not expecting widespread water issues at this time. Temperatures on Sunday are expected to be in the mid to upper 80s for the lowlands and 70s to mid 80s along the higher elevations, which will provide daytime heating to assist with shower/storm development on Sunday.
As this front finally lifts away from the area, there may be a drier period possible Sunday night into Monday ahead of the next system.
LONG TERM /MONDAY THROUGH FRIDAY/... As of 220 PM Friday...
Monday may start off mostly dry with a few scattered showers and storms possible as the upper shortwave moves away from the area and the next system begins to move in. A cold front approaches sometime Monday afternoon/evening bringing another chance for showers and thunderstorms ahead of the front. At the upper levels, a trough will move in from the west over the area through Tuesday providing additional forcing for showers and storms to occur. Some stronger storms may be possible with this system with models indicating some instability present this far out. The GFS is slightly quicker to bring this front into the area Monday afternoon while the ECMWF and Canadian show a similar timing with bringing it in slightly later Monday evening. This front will gradually move through on Tuesday, exiting by sometime Tuesday night. Models are keeping the potential tropical system further to the southeast and then off the east coast, so currently not expecting this system to affect the area.
Following the cold front, upper ridging attempts to build in and surface high pressure is expected to settle into the area giving way to a quiet break for some dry weather for the middle of the week. Temperatures behind the front will be on the more mild side with Tuesday projected to be well below normal. A gradual warm up is then expected to occur through the end of the work week. Precipitation chances may begin to increase into the end of the week as models disagree a bit more. The ECMWF and Canadian keep high pressure at the surface through Friday but the GFS and ECMWF do bring an upper level disturbance toward the area Friday which may lead to chances for showers and potentially thunderstorms.