Marine Weather and Tide Forecast for Galena, OH

KEY MESSAGES
1) Warm and humid conditions today and Thursday. Isolated thunderstorms are possible in the afternoon hours.

2) A cold front will move through the area on Friday bringing the chance for showers and storms. Cooler, drier air works in for the weekend and persists behind a second cold front on Sunday.



DISCUSSION
KEY MESSAGE 1)
Stratus has been slow to erode this morning which has limited temperatures to the low 80s and upper 70s thus far. This cloud cover will likely continue to limit the temperatures this afternoon to the middle/upper 80s as ceilings slowly erode. Dew points combined with temperatures in the 80s could still lead to the heat index values reaching into the upper 90s in locations that see more sunshine later today.

Despite morning cloud cover limiting instability, a few showers and thunderstorms are possible this afternoon as the PBL destabilizes.
Locally heavy rain or gusty winds cannot be ruled out in the strongest storms. Confidence in storms occurring is rather low.

For Thursday, warm and humid condition are expected once again. If cloud cover is less persistent, temperatures could reach a few degrees higher in the afternoon compared today. Forecast highs in the upper 80s combined with lower 70s dew points allow for peak heat index readings getting into the upper 90s. However, the remnants of a MCS may work into the area overnight. Cloud cover from this decayed MCS could once again lead to a cloudy start to the day thereby leading to uncertainty around the highs on Thursday.
Isolated showers or storms cannot be ruled out during the afternoon hours.

KEY MESSAGE 2)
A surface low forms in response to an upper level shortwave trough ejecting east through the Plains into southern Canada on Friday. A cold front associated with low moves through the Ohio Valley during the day which may support showers and thunderstorms. The best chance for storms, some of which could be severe, is well east of I-75 where diurnal instability will be maximized during FROPA. As of Wednesday afternoon, the forecast severe risk over much of the area remains fairly low since instability appears to be weak thanks to a morning frontal passage. An afternoon frontal passage would support a greater severe risk with more instability.

Slightly cooler, drier air arrives behind the front for the weekend.
Cooler air then arrives on Sunday with a second cold front. Cooler conditions look to persist into next week.



AVIATION /18Z WEDNESDAY THROUGH MONDAY/
Stratus has been slow to erode this morning. Stratus is eventually expected to scatter and allow for VFR conditions this afternoon and evening. Cloud cover may increase again later overnight when a decaying MCS works into the area from the west. MVFR ceilings cannot be ruled out although VFR ceilings appear more likely at this time.
VFR conditions are expected for Thursday. An isolated shower or storm is possible this afternoon.

Light southwesterly flow persists for the TAF period.

OUTLOOK... Thunderstorms possible Sunday.

ILN WATCHES/WARNINGS/ADVISORIES
OH...Heat Advisory until 8 PM EDT this evening for OHZ026-034-035.
KY...None.
IN...None.