Marine Weather and Tide Forecast for Byesville, OH

KEY MESSAGES
1) A cold front Saturday afternoon and evening will bring another round of strong to potentially severe thunderstorms.
Damaging wind again appears to be the most likely threat although a tornado and large hail threat is also possible.

2) Much above-normal temperatures continue until the Saturday cold front passage. Behind it, temperatures crash to much below-normal levels. Frost/freeze concerns return by early next week, and even a few Sunday night snowflakes are possible.

DISCUSSION
KEY MESSAGE 1...
Saturday will feature a decaying MCS arriving into the forecast area Saturday morning into midday. There seems to be 2 scenarios with the approach of this line and the development of strong to severe thunderstorms.

There are still hi-res CAMS still suggest a decaying line that dissipates as it arrives into the area. This primes the environment for development later in the day, more like the 20Z to 23Z timeframe. This potentially means a greater severe threat due to the moistening of the boundary layer, greater CAPE and still good shear. In this scenario, only the 90th percentile takes the surface based CAPE just over 1400 J/Kg. This scenario shows a better setup for an isolated tornado to go with the damaging wind threat.

The second scenario suggests the weakening MCS slows through Ohio and arrives into southeast OH and the rest of the forecast area between 18Z to 20Z. Here, the line is expected to reinvigorate along. with the shear available, owing to a low CAPE high shear event. Here, the 90th percentile gives just over 1000 J/Kg. Morning cloud cover will inhibit this further. This is evident in some of the HRRR runs, suggesting the event to fall apart. This scenario hints at a damaging wind event.

Ensembles have been siding with the scenario 2 solution with strengthening occurring between the 16Z and 18Z timeframe. It is worth noting that in either scenario that the probability of exceeding 500 J/Kg is still around 50% and 60% respectively. At the very least, a wind threat is evident. As such, agreed to go with neighbors and go with a 90th percentile wind gusts through today, especially with the HRRR showing a stout 40 to 50 knot 850MB LL jet.

KEY MESSAGE 2...
The cold front passes through on Saturday night with much colder temperatures and strong gradient. This will usher in colder temps with lows on Sunday being on the order of 3 to 5 degrees below normal. The coldest core of the air mass will arrive Sunday night with lows being 10 to 15 degrees below normal with the potential of a few snow showers in the higher terrain.

The low temperatures expected on Monday and Tuesday morning will be well below normal with the probabilities of temperatures being below 32 in the 60% to 80% range. Its fairly certain that there will be frost/freeze concerns to begin the week.

AVIATION /06Z SATURDAY THROUGH WEDNESDAY/
VFR is expected through this morning as mid and high level clouds increase ahead of an approaching cold front. Ongoing showers and thunderstorms will continue to slowly approach from the west. There is still some uncertainty in the maintenance of this area as it advances east, though the latest guidance indicated some weakening of the storms should occur through morning.

This should result in a prefrontal trough, where additional thunderstorms are expected to re-intensity this afternoon into the evening as it tracks east across the region. Maintained TEMPO mentions for thunderstorms at all airports for the most likely time of occurrence. Some storms could be severe, depending on the extent of destabilization that occurs through the day. Storms should also be enhanced by a low level jet, which should also result in gusty wind through the day outside of any storms. Expect S-SW wind with gusts from 25-30kt by mid morning.

Widespread MVFR is expected with post frontal showers this evening and overnight as the front continues eastward. A wind shift to the WNW is also expected after FROPA, though gusts should gradually diminish through the evening.

Outlook...
Areas of MVFR cigs are expected to continue Sunday into Monday under a crossing upper trough and cold W-NW flow. Scattered rain and snow showers are also expected at times. VFR returns later Monday and Tuesday under high pressure. Another cold front will bring shower and restriction potential on Wednesday.

PBZ WATCHES/WARNINGS/ADVISORIES
PA...None.
OH...None.
WV...None.