Active Pattern is on the Horizion

Summer seems to always make a comeback around here with highs again in the 80s the last two days. We can never say never around as the weather always has a tough time making up its mind. Do not get used to summer temperatures because an active pattern is on the horizon.

Check out the foliage at Nolin Lake! (@wxornot)

Fall Foliage Update!

Current fall foliage across the Ohio Valley!

We are nearing peak foliage across WABBLES with almost all the trees showing color right now! This time next week will likely be the peak of fall foliage across the area so get those cameras ready! You can see in the map above that the Appalachian mountains have already peaked and areas well to our north.

Temperatures Above Average Today

Warm Friday before Cold Front Moves In

Friday is the day the weather is going to flip on its head. The cold front will be on approach while warm southerly winds continue for our area. Look at this cold front pushing in on Friday! That is one steep temperature drop with a 20-30 degree drop in about an hour.

Sharp Cold front moves in Friday night (Pivotal Weather)

Now the question is will there be any rain with this front? The answer is yes and a majority of it will fall behind the front. Showers and thunderstorms will be possible Friday night as the front passes. Here is a look at the simulated radar as the front pushes through.

Cold front with showers and a few storms Friday night. (Pivotal Weather)

Now we can’t rule out a few showers developing ahead of the front Friday afternoon. Rain chances look to be greatest after sunset across the area as the front passes.

Conditional Severe threat

We have been placed under a marginal risk for a small risk of damaging winds and large hail. This threat will be determined based on how much instability builds during the day on Friday. We are under a 1 out of 5 risk right now.

Here is an excerpt from the NWS Louisville forecast discussion…

Model soundings from the higher resolution models show rather
marginal lapse rates across the region.  However, with heating we
should be able to attain at least 1000-1300 J/Kg of CAPE in some
areas.  Effective bulk shear values of 30kts were noted in the model soundings as well.  Overall thermaldynamical and kinematic setup would generally favor multicellular/linear convective mode with a damaging wind threat.  Overall severe threat though is strictly contingent upon available instability in the afternoon.

We will monitor closely to see how this threat evolves. Again the main threats will be strong winds and hail.

Rainfall totals will remain light with most locations receiving less than .25in of the wet stuff. Heavier downpours may result in locally higher amounts but that looks to remain isolated.

Shown above are rainfall totals through Sunday (Pivotal Weather)

Looking at the winds, the pressure gradient won’t be really tight but enough to increase the winds. You can see below how the pressure lines (isobars) get closer together. This is where we see an increase in winds behind the cold front. Winds of 10-15mph with gust up to 20mph Friday night will be possible.

Winds increase behind the front

Temperatures Friday night will drop down into the low 50s under mostly cloudy skies. The winds should relax come Saturday morning so not expecting the winds to stick around.

Lows Friday Night (Pivotal Weather)

Dry Weekend but Most Cloudy

Moving into the weekend the clouds are going to hang tough for most of the day Saturday. One way we can tell is by looking at a forecast sounding. Think of a forecast sounding as cutting the atmosphere in half and looking at from the side vertically. Here is an example of one for Saturday afternoon over Bowling Green.

Forecast Sounding Saturday afternoon

Where the temperature line and dew point line are touching is where the atmosphere is saturated. This most likely is where clouds will develop! I don’t mean to get too technical, but I thought to throw something different in there today!

Temperatures Saturday will struggle to get out of the 50s. Winds will stay light, but it will be a damper of a day. Temperatures drop down to the low 50s Saturday night.

Clouds try to break come Saturday

Sunshine will try to break Sunday as southerly flow returns to the area. Temperatures should top out in the low 70s so overall Sunday is not looking to bad. Dry conditions should persist through out the day.

A Look at Next Week

The jet stream is going to get active next week which means increased rain chances across the area. Moisture will start pumping into the area which should evolve with multiple disturbances passing through.

Active Upper Level Jet next week

Increased rainfall chances are showing up on the ensemble data here is look at the GEFS.

We will be closely monitoring as we head through the weekend so check back for updates!

That’ll do it for today! Thank you for reading! We hope that you have a wonderful Thursday! For more information, follow us @wxornotBG on our other social platforms

Weather 10/22/2020

A final taste of summer today thanks to sunshine coinciding with well above-average temps. Active pattern follows Friday into next week.

Posted by Landon Hampton on Thursday, October 22, 2020