Marine Weather and Tide Forecast for Alexandria, OH

NEAR TERM /THROUGH TONIGHT/
Coverage in showers and thunderstorms beginning to increase this afternoon with the help of diurnal heating. Cold frontal boundary is currently draped around the I-71 corridor, with majority of convection expected SE of this interstate. Moderate MLCAPE values of 1000-1500 J/kg have developed, but overall shear values remain marginal at best. This will result in mainly single cell or mult-cell clusters today, with damaging straight-line winds being the primary severe threat. However, DCAPE values appear to remain capped at ~700-900 J/kg, so the downburst environment isn't overly impressive.
Thus, severe storm potential will be limited, but a handful of storms may still produce localized gusts of 40-50 mph.

The primary concern with these storms will shift to flash flood potential. Synoptic/mesoscale environment remains conducive to flooding through this period, along with the next couple of days given the quasi-statoinary front, humid air mass, anomalous PWATs of 1.75"-2.00" and the signal for repeated rounds of thunderstorms.
Locations that receive multiple rounds of storms will have their soils primed to shorten the amount of rainfall needed to cause flash flooding. Best flooding potential for this period will be through the late evening hours, although this threat still remains fairly isolated today.

A bit of a lull in convective activity is expected during the middle of the night, but there is a signal in CAMs to show a complex of storms developing near the Tristate region early Friday morning.

SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/
Complex of storms expected near/south of the OH River Friday morning as the cold front sinks southward. Eventually, this boundary will stall near or just south of the river and remain there for majority of the daytime hours. This will result in a relative minimum in convective activity for our CWA However, keep in mind that isolated showers/storms may still develop during the daytime hours, but coverage should be lower. Daytime highs trend a couple degrees cooler in the lower to middle 80s.

The quasi-stationary boundary will begin to shift back northward as a warm front Friday night. This will bring renewed chances for shower and thunderstorm activity, especially near the Ohio River. Severe storms are not expected Friday night, but we will have to keep an eye on any training storms or efficient rainfall over hard hit areas.

LONG TERM /SATURDAY THROUGH THURSDAY/
Extended period starts with pretty good ensemble agreement of high convective precip potential and PWs at 2.0+ Sigma anomalies/above the 99th percentile across much of the area, creating a more focused flood threat through the weekend. Where the uncertainties lie are where any MCS activity sets up/tracks, as this would affect latter convective system initiation and further prime ground conditions for additional rounds of convection.

While Saturday begins with overall zonal flow, ridging across the southern plains sets the region up for NW flow and, combining with the high PWATs, sets up a ridge rider pattern with the potential for bouts of repeated heavy rain. Still fairly modest confidence in where this sets up. While potential for localized flooding and some areas of flash flooding exists area-wide, current thinking is the greatest risk will be especially across IN/Southern Ohio/Northern KY Saturday and Sunday.

While Monday could bring a relative lull in convective activity with the convective focus further south of the Ohio River, still potential for at least scattered showers and storms especially across the southern forecast area.

Beyond Monday, increasing convergence on a ridge building solution with 590+ H5 heights pushing into the forecast area, which could increase heat indices toward 100 in the Tue/Wed timeframe.

AVIATION /19Z THURSDAY THROUGH TUESDAY/
Thunderstorms will develop during the day. Vsbys will be reduced at times with the thunderstorms. Additional thunderstorms will be possible near the end of TAF period. MVFR cigs will be possible at times, especially at the end of the TAF period.

OUTLOOK...Thunderstorms are likely through Monday.

ILN WATCHES/WARNINGS/ADVISORIES
OH...Flood Watch until midnight EDT tonight for OHZ073-074-077>082-088.
KY...Flood Watch until midnight EDT tonight for KYZ089>100.
IN...Flood Watch until midnight EDT tonight for INZ075-080.