Issued: 7pm on Thursday, June 27th 2024
Technical Forecast Discussion
Short-term Forecast (Thursday 6/27/2024 through Sunday 6/30/2024):
A weaker trough will exit the area and transition into a weak ridge by late Friday. During this transition period, a surface high pressure core located of Lake Ontario will push out to the Atlantic Seaboard, and currently easterly flow will become more southeasterly, then southerly by 00Z Saturday. This will subsequently advect temperatures near 90 degrees and dew points in the upper 50s into Southern Ohio region. A mid-to-upper level shortwave trough is forecast to spur a low pressure core further north of the Great Lakes, which will lead to a frontal system passing through the area.
The warm front from this system will enter northwestern Ohio by around 6Z, continuing eastward through 12Z. Surface temperatures across much of central Ohio range from the high 70s to low 80s, and surface dewpoints range from the low-to-mid 70s as well. Morning convection in particular poses the greatest threat to organized storms later in the day, and this too remains relatively disputed in terms of timing. Pockets of non-severe convection may arise behind the passage of the warm front in the early morning hours of Saturday. Should this convection be more organized, however, much of the available potential energy may be spent thus limiting the probability of severe storms further in the day. An upper-end scenario places cape at above 2000 J/kg for the region, though with minimal 0-1 km shear (~17 kts) is seen in eastern Ohio into Pennsylvania, and much of Ohio does not exhibit signs of particularly robust shear at a baseline, this appears to be more of a disorganized multicelluar event. Despite LCLs and LFCs remaining around 900 hPa, convection firing in southeastern Ohio depends on the strength of forcing from this cold front. Should storms fire, these will likely be more centered in the Eastern-Central Ohio region, with damaging wind gusts being the primary threat. Though, with non-zero shear, the possibility of a weak, isolated tornado cannot be ruled out, albeit much further east.
A few showers and a possible rumble of thunder are possible behind the cold front as it passes through the region by early Sunday morning. A more positively tilted trough will dig into the northern Ohio region, placing us in the right-exit region and promoting a development of high pressure as it builds in the area. Thus, conditions as well from the more northwesterly flow will promote a cooling trend amidst calmer conditions.
Long-term Forecast (Monday 7/1/2024 through Wednesday 7/3/2024):
High pressure will be maximized on Monday as we upstream of the trough that will have moved to the East Coast. Cooler temperatures in the high 70s will advect into the region amidst much drier conditions. However, a building ridge will make these conditions short lived as southwesterly flow pushes a warm, moist airmass back into the southern United States. Subsequently, temperatures will push into the lower 90s by Wednesday alongside dewpoints in the mid 60s. Potential heat danger is possible given heat index values reaching the upper 90s at that time.
