Marine Weather and Tide Forecast for Obetz, OH

KEY MESSAGES
1) Dense fog tonight into Monday morning.

2) Temperatures rising much above normal.

3) Chance of rain and increased winds mid to late week.

DISCUSSION
KEY MESSAGE 1) Dense fog tonight and Monday morning.

Update...
Very good signal for dense fog overnight. This is setting up an ideal situation for dense fog. Abundant low level moisture due to wet ground from rain and residual snow melt, clearing late in the day into early evening (so not much drying), and surface high pressure builds in overnight.

HRRR guidance shows >80 pop for <1/4 mile visibility centered along the I-71 corridor. Already observing 1/4 mile at ILN. High confidence regarding expansion of dense fog overnight which will impact the Monday morning commute. Therefore - Have issued a dense fog advisory for our entire area thru 11 AM Monday.

Previous Discussion...
Reduced visibilities have been occurring with the stratiform rain moving through the region. Rainfall is expected to end early this afternoon, but reduced surface visibilities are lingering behind the precip. Expect the potential for patchy dense fog through at least the early afternoon, with minor improvement expected from west to east. However, some patchy fog may linger in portions of the fa through the remainder of the day, particularly SE of I-71.

More impactful fog potential exists tonight into Monday morning.
Guidance remains pretty consistent in showing widespread fog developing across the region. There is a high likelihood that visibilities decrease below one mile across our CWA, with several locations dropping to 1/4 mile visibility or less. This will result in potential impacts to the morning commute on Monday. A Dense Fog Advisory will likely be needed this evening.

It should also be mentioned that temperatures will drop to near or just below the freezing mark. While this doesn't appear to be a slam dunk scenario for freezing fog, cannot completely rule out some deposition onto pavements early Monday morning, particularly on bridges/overpasses. However, given the lack of a prolonged period of sub-freezing temperatures overnight (if they even occur), thinking that this potential remains very limited.

KEY MESSAGE 2) Temperatures rising much above normal.

H5 ridge will begin to propagate from the central CONUS towards the Midwest region early in the work week. A gradual warming trend will ensue underneath this synoptic feature, resulting in temperatures well above seasonal norms. While some modfication of this ridge occurs mid-week, persistent, southwesterly flow will continue to usher in a warm air mass across the Ohio Valley. Warmest temperatures are expected on Tuesday and Wednesday, approaching record highs.

KEY MESSAGE 3) Chance of showers/storms and increased winds mid to late week.

As the H5 ridge dampens mid-week, a surface low will develop out in the Northern Plains. ILN CWA will be placed in the warm sector of this low on Wednesday. There remains enough forcing and moisture availability to keep rain chances in the forecast on Wednesday, with fairly good model agreement on this potential. Cannot rule out a rumble of thunder given the weak instability present. Surface pressure gradient will tighten with the strengthening surface low to our west, which will increase the magnitude of southwesterly winds (aiding in the near record high temps). Sustained southwesterly winds of 15-25 MPH expected Wednesday, with gusts up to 35 MPH possible.

Another round of precipitation is expected late Thursday into Friday.
Models continue to try and build in some instability in across the Ohio Valley, thus keeping at least a slight chance mention for a few rumbles of thunder. A cold front will eventually swing through the region Friday, ushering in cooler air for the weekend. As thermal profiles cool, cannot rule out some snow mixing in if pcpn lingers, particularly near/north of I-70.

AVIATION /00Z MONDAY THROUGH FRIDAY/
As system moves off to the east clearing is taking place from the northwest. This is setting up an ideal situation for dense fog.
Abundant low level moisture/wet ground from rain and residual snow melt, clearing late in the day into early evening (so not much drying), and surface high pressure builds in overnight.

High confidence in IFR to LIFR vsbys tonight for all terminals due to dense fog development. Some of this fog will also lift and creating LIFR ceilings.

Improvement of these low CIGs and vsbys will be slow Monday morning, but will eventually begin to scatter out by the late morning hours, with VFR conditions expected by afternoon.

OUTLOOK.. MVFR ceilings and wind gusts at or above 30 kt are possible on Wednesday.

ILN WATCHES/WARNINGS/ADVISORIES
OH...Dense Fog Advisory until 11 AM EST Monday for OHZ026-034-035- 042>046-051>056-060>065-070>074-077>082-088.
KY...Dense Fog Advisory until 11 AM EST Monday for KYZ089>100.
IN...Dense Fog Advisory until 11 AM EST Monday for INZ050-058-059-066- 073>075-080.