Department of Meteorology and Atmospheric Science at Penn State.

This is Weather World.

Good evening, Pennsylvania, and welcome to Weather World.

On this Friday, October 9th, I'm Marisa Ferger alongside Rob Lydick and Rob.

Mother Nature once again giving us just a ten out of ten autumnal day here.

It's not quite 1010, it's ten nine.

But still we're going to give it a ten out of ten today.

Plenty of sunshine breezy.

I think tonight's going to be a good night for high school football games tomorrow.

The pick of the weekend.

And then Isaias will pay us a visit.

Okay, well, Rob will give us all the details about that in just a couple of moments.

And also tonight here on the show, I'll have the extended forecast.

Looking at the weather for the upcoming workweek.

And then Karl Schneider will join us for week two trends.

But first, here's Rob and thanks very much, Marissa, as we gear up for a big game tomorrow, the annual Penn State whiteout tradition.

Here's a look at our time lapse today at Beaver Stadium.

You can see cloudy skies through most of the day.

Just a few high clouds streaming in as we go through this afternoon.

And that will be the trend as we go through tonight.

More high clouds will be coming in.

I think we'll see high clouds cover the sky tomorrow.

No precipitation expected to begin the weekend.

But then we'll see.

Kind of a washout of a day expected for our Sunday.

Here's a look at the satellite radar picture.

You see a few of those high clouds streaming in to areas mainly south of the turnpike.

We'll see an increase in those high clouds as we go through tonight.

But dry conditions are on the way as we begin the weekend tomorrow.

So if you have any outdoor plans to maybe do some raking of the leaves or do some yard work, get outside to tailgate, it's going to be a good day for that tomorrow.

Temperatures today, low 60s to low 70s for the most part.

I think we'll see kind of a repeat of that as we go into tomorrow.

Maybe not quite as breezy as it was at times today across the national perspective, you see where cool air is actually all the way down the spine of the Appalachians into the southeast, because we've got more clouds there, and eventually some precipitation will be inundating parts of the southeast anywhere from two to even six inches of rain expected with Isaias remnants.

Meanwhile, the heat kind of stays at bay over the plains.

Temperatures there well above average for this time of October.

Okay, here's a look at the satellite radar picture across the country.

The main story, of course, is Isaias.

We can now see the depiction of this coming in with some of the radar imagery bringing some heavy rain to the panhandle of Florida, inundating parts of Alabama and Georgia.

As we go through this afternoon and evening.

Not officially making landfall yet, but currently it is now confirmed to be a category three hurricane.

A maximum winds at around 120mph.

Gusts up to around 150mph.

With this storm, some of the surge anywhere from 4 to 7 or eight feet along the Florida Panhandle, as this is expected to make landfall going into tonight.

And we'll be dealing with the remnants of this storm system as we go into our Sunday tomorrow.

Just some high clouds from the storm.

No precipitation that will arrive tomorrow night.

And it may be heavy as we go into the day on Sunday.

So high pressure keeps us dry tonight that will begin departing one more dry day on the way tomorrow.

I think.

In fact, with the high clouds overhead, we should see a vibrant sunset tomorrow night.

And then as that high departs, we see the remnants of Isaias inundate the Ohio River valley and push northeastward.

We'll see periods of rain really throughout the day on Sunday.

It's going to be a good soup day or a good book day to stay inside, as I think we'll see rain off and on throughout the day, eventually tapering off as we go into Sunday night.

When all is said and done, I think we could be looking at a widespread half an inch to an inch of rain, though locally higher totals may be possible, some places could see maybe an inch and a quarter to an inch and a half, especially in south central Pennsylvania, at least according to a couple of our forecast computer models.

So for tonight, we'll call it clouds creep in, temperatures in the cool spots mid 30s across the northwest plateau, low 50s off to the southeast with increasing high clouds for everyone and some patchy valley fog possible as we start the day tomorrow on Saturday.

Pick of the weekend mid 60s to mid 70s with high clouds overhead.

Maybe a vibrant sunset mild in the west.

Temperatures there in the low to mid 70s with rain arriving southwest to northeast.

By the way, don't forget the latest fall foliage report did come out yesterday showing peak color across the northern tier of Pennsylvania, approaching peak color in parts of the laurels, central Mountains and Alleghenies, and just starting now off to the southeast.

So tomorrow's the pick of the weekend for leaf peeping, because Sunday it's going to be a soggy day, widespread half an inch to an inch of rain with locally heavy rain, possible periods of rain off and on mid 50s to mid 60s for daytime highs with some gusty winds perhaps up to around 20 or 25mph.

At times.

It will be a damp and breezy kind of day.

Eventually the showers begin to taper off going into Sunday evening and overnight, a few lingering showers into Monday.

Speaking of, we've got the extended forecast up next.

Although we're going to see a series of some fronts pushing through the Keystone State during the next workweek, I think they're going to be pretty moisture starved.

So I think in the next seven day period, the wettest day is actually going to be this upcoming Sunday.

With the system you've already heard about and any other fronts that move through are just going to bring some gusty winds and some changes in temperatures with just a slight chance of some light precipitation.

Before we get to that, though, the water vapor satellite imagery, you can see this big ridge of high pressure that's dominated out west, bringing with it the record warmth they've seen out there.

Of course, we have this upper level low churning in eastern Canada, and that's been bringing the drier air into this neck of the woods.

And of course, all eyes on the Gulf as Isaias makes its beeline for the Florida Panhandle.

Now, by the time we get to Monday, big changes.

Notice that ridge out to the west replaced with this deep trough that ridge has pushed into the Mississippi Valley, where I think we're going to have record heat in many locations in this part of the country, not only on Monday, but through the middle of next week.

And then here is our exiting trough with the tropical moisture that's going to be pushing off on Monday.

Weak ridge across our region being replaced.

You can see more of a flat line here.

A very weak boundary is going to be moving in at the surface on Tuesday.

Could bring a few light showers.

I think cloud cover and wind is going to be the bigger story for Pennsylvania.

Then a ridge moves in for Wednesday.

So I think that's going to be a quiet day, and then a next storm system is going to be knocking on our doorstep sometime Thursday into Friday.

And again, I think wind is going to be the biggest part of that story.

Now, looking at this a little more depth here with the moisture tracker, remember, the deeper the color, the more moisture is available between the surface and the cloud level.

We also have isobars at the surface here.

So this is an area of low pressure circulating counterclockwise.

This is what was left of Isaias.

And it's storm system pushing out.

So a few showers in southeastern Pennsylvania in the morning on Monday.

But they exit.

And I think it will be a mainly dry day for all will actually clear out a little bit.

And then on Tuesday, this weak area of low pressure to our north and it's trailing cold front, the cold front is going to slide through Pennsylvania on Tuesday into early Wednesday, bringing with it some clouds from north to south.

Not a lot of the way in precipitation wise.

And then a brief reprieve on Wednesday.

Then this next system, an area of low pressure is going to sneak up into the Great Lakes.

It's going to be a warm front extending eastward from it.

So I think on Thursday, sometime late in the day, that moves through again.

Cloud cover, slight chance of some showers and thunderstorms.

And then you can see the cold front here extending into the Mississippi Valley that will move through on Friday, again, bringing a slight chance of some precipitation.

So let's show this to you a little bit in an easier form here.

Average highs typically in the upper 50s to upper 60s this time of year.

So warmer than average on Monday.

Again starting out cloudy, especially in the southeast where they could have some showers as that system exits the region.

We all clear out late in the day Tuesday.

Clouds return ahead of that next system, but the temperatures really bounce upwards about ten degrees above average.

That front moves through, bringing gusty winds.

Just a few scattered light showers behind it.

A cooler day, but average for this time of year with some sunshine returning.

And then Thursday into Friday.

That next storm system bringing cloud cover, breezy conditions and just a slight chance of a few showers and thunderstorms.

How does the week to period look?

Karl has that coming up next.

This week two period should begin with breezy conditions and a little bit of unsettled weather.

More of a continuation of the end of Marissa's extended period.

Then things look considerably calmer and drier for the middle of the week two period, so I'll break that down in just a moment.

We'll start here, as always, with a look at the average highs and lows during the middle of this week two period.

And these numbers are declining at about 2 to 3 degrees per week.

I think we're generally going to be around these values, especially in the second half of my period.

So we're looking at seasonable fall like conditions for much of week two.

But we'll start here once again with a look at the upper air pattern from the European Ensemble.

That's the ensemble members are all the different colored lines.

The mean flow is represented by the white line.

On day zero, we see the upper level reflection of Hurricane Isaias moving onshore.

But I'll quickly jump here towards the towards the end of Marissa's extended forecast period, when we talked about a bit of a ridge and some warmer air building in for the end of the week before a cold front will come through late Thursday, kind of Friday time frame.

And behind that, you'll see this upper level trough propagate eastward near our area on Saturday and eventually come overhead on Sunday.

So I think by Sunday, some chillier air will be coming into Pennsylvania for sure.

And some models are showing a pesky upper level low kind of hanging around in the Saturday Sunday time frame.

That will lead to a lot of cloudiness, some breezy conditions, potentially some lake effect showers.

But I don't think we're cold enough for many of us to see snowflakes.

Switching gears, though, to the upper air pattern and jumping ahead on Monday.

This is the upper air height anomalies combined with the mean flow in black.

You see here with the position of the ridge axis to our west, we're kind of downstream of that, and that's a favorable position for surface high pressure to be maintained and strengthened.

So that's why I think Monday, even moving into Tuesday, Wednesday, this is going to be a period of dry weather here in Pennsylvania.

And despite the warm colors here on the upper air temperature anomalies down near the surface, I think the surface high pressure in control is going to help unlock some of that cooler air from the weekend.

So temperatures will be near average near those fall values that I showed at the beginning of the segment.

Moving into Wednesday though, see a bit of a weakness in the flow to the west.

That's a sign that maybe weak front could try to propagate through here.

I don't know that there would be much moisture associated with that, but generally the theme is moderate temperatures, seasonable for fall, and limited precipitation risks.

For much of the second half of this period.

So here's how we summarize in the week two checkerboard.

I'll try to add some value here beyond what you see.

So Saturday and Sunday.

Saturday is more of a transition day to cooler regime by the time we get to Sunday.

The reason I don't have any precip confidence on here is it's hard to pinpoint, especially at this time range, which one of these days would see widespread precipitation across the state, if any.

I think it's probably light.

It's related to an upper level low.

It might be kind of showery in nature, but after that feature moves out, we'll have to watch for maybe another widespread frost and freeze scenario across central and northern Pennsylvania when we get some clearing skies towards that Sunday, Monday kind of time frame, and we'll have dry conditions.

Looks like clear skies for the middle of this period, and temperatures look to be right around average.

So very seasonable for this time of the year.

Later in the period.

I don't have any color because confidence is low, but if I had to lean one way or the other, I'd lean on the drier side for precipitation.

So that's week two trends.

We're back with the recap.

Up next.

And a good night for the marching bands in Pennsylvania, as we'll just see some high clouds streaming overhead.

High pressure remains in control across the northeast tonight, keeping things calm.

In fact, the breeze that we had out there today will calm down.

We'll see some patchy valley fog by morning.

Temperatures in the mid 30s in the cool spots.

Low 50s in the warm spots on Saturday.

It's the pick of the weekend.

We should see some high clouds overhead, but some filtered sunshine through the day mid 60s to mid 70s.

Should do it for daytime highs.

Warmest in the west.

I think we will be looking at the chance for a vibrant sunset before rain arrives from southwest to northeast going into Saturday night.

And then it's going to be a washout of a day on Sunday.

I think we'll see periods of rain off and on all day long.

We'll see some widespread totals of anywhere from half an inch to an inch possible, though it will be locally heavy as well.

Breezy to temperatures in the mid 50s to mid 60s.

A good day to stay inside and grab a book.

Marissa.

As we see kind of a soggy end to the weekend, I feel like Mother Nature has been giving us that theme over the past few weeks, where Saturdays have been really nice, and then Sundays have been really good indoor days.

We should get one dry weekend day though.

Well, hopefully soon.

Yes.

All right.

Well, thank you so much, Rob, for your forecast.

And thank you for joining us.

Come back again next week.

We'll have water watch on Tuesday.

And it's the middle of the month.

So climate watch on Wednesday.

We'll see you then.