1-9-19 Weekend Snowstorm Possible

1-9-19 Weekend Snowstorm Possible

A good old fashioned snowstorm looks to be brewing for the region this weekend. There is still a lot we don’t know yet since we are three days out, but we are getting a clearer picture than we’ve seen the past few days. Snow looks to move into the region late Friday night, after Midnight. Waves of snow will be in the area until Sunday afternoon. The rain/snow line will also set up shop somewhere in our area. Every model varies right now on placement of that line.

The Canadian has this:

That leads to some hefty snow totals.

The GFS has a pretty similar idea. Again, the rain/snow line is close to the Ohio River for some of this event.

Snow totals on the GFS are lighter.

The NAM does not see the whole event yet, but it’s a healthy hit for what it sees.

Snow totals through Saturday evening look like this. NAM is juicier than the other models. NAM is also not in its best element this far out, so take with a few grains of salt.

The Euro was the coldest of the models, but it has now also brought the rain snow/line into Southern Indiana. Gives a healthy hit of snow at the onset, but quickly changes to rain for folks south of the US-50 corridor.

It’s a very healthy hit of snow, though, for much of Indiana. The totals from US-50 and southward into Kentucky arrive before the rain and would be washed away by the rain.

This storm is not on shore and fully sampled in our upper air network just yet. It will be until Friday before I’ll issue a specific forecast with snow totals expected. But a general 1-3″ looks likely for much of Southern Indiana and parts of Illinois and Kentucky at this point. There will likely be a swath of 2-4″ or even 3-5+” snow somewhere, but that placement just can’t be known with certainty this far out. Figuring out how far north the rain/snow line goes will be key. And there is too much variance in the data to know right now.

Either way, I’d be preparing for some snow this weekend. Travel looks difficult over a good chunk of the area Saturday. More updates to come. Be sure to follow me on Facebook and Twitter for frequent updates.

12-19-18 Rain Arrives Late Tonight; Tracking Christmas Eve Light Snow Chance

12-19-18 Rain Arrives Late Tonight; Tracking Christmas Eve Light Snow Chance

Our milder air is bringing with it some rain to end the week. Showers will move into the area late tonight and those chances will last through Friday. Some of the data hints that the rain may end as light snow showers. That assumes the cold air catches up to it in time and that is not agreed upon by the modeling. Some say yes, most say no.

Either way, the models that do give snow, let’s just say it’s very light. It would be a slushy accumulation and since the ground is warm still, probably limited to grassy and elevated surfaces. Would melt pretty quickly if we did see anything. But to be fair, I’m not sold we even see this. I’ll be tracking it and have updates. We shall see.

As for rain in general, not a lot for most of the region. A few tenths of an inch for most. You have to head over into Eastern Kentucky and Ohio before you get an inch or more. That’s where the heaviest rain bands will go. Light event for Indiana, Illinois and Western Kentucky.

We’ll dry out for the weekend and then our next chance at something comes late Sunday night into Christmas Eve Monday. That’s when what looks like a pretty weak piece of upper level energy will roll through. The data is all over the place with this one.

Last night, the Canadian had a pretty decent little hit of snow for the area.

This morning, it’s a snow Grinch.

The main difference here is that it completely changed the strength and positioning of the upper level energy. That leads to a big difference at surface. In other words, a deepening surface Low vs an open wave (with no surface Low at all). A deepening Low wants to go poleward, shifting precip north. An open wave means it remains very weak and may even miss us altogether.

The new FV3-GFS also shows this system, but keeps it weak as it rolls through.

Euro sees this as well. It’s also not impressed and it’s a much warmer solution, so gives rain.

These little pieces of upper level energy are tricky for models to get a lock on. I suspect it’ll be late Friday or even Saturday before we really know with much confidence where this tracks and what impacts it will have. If it does track over us and bring us snow, my suspicion is that it would be pretty light. Temps look to be in the 30s or low 40s Christmas Eve, depending on which model you fancy. So accumulations, while possible, would probably be limited. But we still have four to five days to go, so there is plenty of time for the modeling to adjust.

Next week will be active. Another system rolls through right after Christmas. Likely a rain maker and could get fairly windy here with it. With the Low north of us, we’d be in the warm sector and could see temps well into the upper 50s with that south wind.

That storm is followed up with another one to end the year. It’s not as strong on the modeling as the one right after Christmas, but note a very similar track to the Low. We get in the warm sector again and end up with breezy, warm conditions with rain.

I still think we change to a much colder pattern as we go into January. Modeling consistently is indicating what we refer to as a Sudden Stratospheric Warming (SSW) event taking place at the North Pole that will disrupt and send the Polar Vortex southward for a visit. That would signal the possibility of some major cold being pumped into the USA in early January sometime. It’s not a lock yet. But multiple models are indicating this. It’s something we’ll need to watch closely. A disruption like this happened back in the winter of 2014-15 and sent us well below zero for a few days. Could we repeat that? Let’s hope not, but a SSW makes that kind of cold possible.

12-13-18 Rainy End of Week; Colder Pattern (with snow?) Looms for Christmas

12-13-18 Rainy End of Week; Colder Pattern (with snow?) Looms for Christmas

A milder pattern has returned to the area. It’s a breath of fresh air for a few days after all of the cold that we’ve seen over the past two months. The milder air has brought rain with it, though.

A cutoff Low will spin south of us and eventually move through this weekend. That will bring several periods of showers and sometimes heavy downpours with it. It won’t be a total washout, but we will certainly have some very rainy times coming our way.

Much of the area can expect to see around 1-2 inches of rain by the time it’s all said and done. Again, that will be spread out over now through Saturday evening. Rain finally moves out late Saturday, but it’s possible we could see a bit of drizzle and continued cloudy skies through part of Sunday. That’s not uncommon with these type of setups.

Either way, it’s going to be mild. Look for 40s and 50s to dominate the next 10 or so days. We’ll dry out next week, too.

A big pattern change then lurks as we get closer to Christmas. In the data above, note that we drop back to the 30s for highs on Christmas Eve and then it gets progressive colder. How fast that transition back to colder temps will take place is still up in the air. It might come in time for Christmas or it might be a few days after, as shown in the image below. Either way, we have solid indications that we’re headed back to a ridge in the west and trough here in the east kind of pattern. That leads to cooler than normal temps for the eastern CONUS.

Temps would go back to something like this around and after Christmas.

There are also some hints in the data that our old friend, the Polar Vortex, may return for a visit. You can see in the image below that a major warming event (what we call Sudden Stratospheric Warming, or SSW for short) will take place right around Christmas time. That displaces the Polar Vortex and sends the coldest air on the planet southward. This would have major implications for our weather as we end December and enter January. If this comes to pass, we could be looking at some record cold setting up for early January. Something I’ll be monitoring closely.

This timeframe also looks pretty active. There are multiple systems that will roll through the last week of December. A few model runs ago, the GFS gave us a healthy winter storm for Christmas Eve and Day.

Today’s run still has a snowy look to it, but a totally different setup. The reality is that we are still about 12 days away from the return to winter, so that’s more like a thousand years here in model land. We have a ton of time to figure this out and I suspect it will be around Dec 21st before we’ll start to get a better handle on this. So for now, it’s simply a heads up and just know that I’ll be monitoring it and bringing more updates as we get closer.

Enjoy the milder weather while we have it! Winter comes back in full force to end the month.

Be sure to follow me on Twitter @WilhiteWx for more frequent updates.

12-4-18 Snow Showers Tonight; Rain to Snow Thu?; Big Weekend Winter Storm?

12-4-18 Snow Showers Tonight; Rain to Snow Thu?; Big Weekend Winter Storm?

Multiple chances of snow come our way this week. A few snow showers will be around this afternoon and evening. Not everyone will see these, but many will. We’ll be fine during the daytime, but as night comes and temps drop, a few slick spots could develop on untreated surfaces.

Accumulations look limited, but a dusting to a light coating will be possible for some. Again, not everybody sees these, but many will.

Another front rolls through on Thursday. That looks like it might be a rain/snow mix. Some of the data keeps it all snow, such as the FV3 below. But most doesn’t. Accumulations with that one would be very limited unless something drastically changes.

The bigger story is what arrives this weekend. A storm slides to our south and we appear to be on the northern edge of the precipitation here in the Ohio Valley. Most of the modeling makes a sharp cutoff right through Southern Indiana between snow and no snow.

The models have been varying widely and that will probably continue for another day or two. Here’s the latest.

GFS. This had been much farther south, but has moved up to include parts of the area. A nice hit of snow for Kentucky and parts of Southern Indiana.

FV3 (new test version of the GFS) is even more north than the GFS. Very nice hit of snow for the area.

Canadian is similar. But has more of a warm component than the others. That’s something to keep an eye on. Snow with rain mixing in at times. A miserable setup for snow lovers.

All of them are similar, but they do have slight differences. Again, note that Southern Indiana is on the far northern edge in all of them. What kind of snow totals would these bring?

GFS has the cutoff right along the Ohio River right now.

FV3 is a tad farther north.

Canadian has a nice it for Kentucky and does have a bit of snow just barely into Southern Indiana. Again, a sharp cutoff.

We are still four days away from impact, so quite a lot can still change in the data. Hopefully, I’ll be able to dial in more specifics by Thursday night.

Here is the general area I am watching. If the Low continues to push north in coming model runs, we certainly could be talking about more than just extreme Southern Indiana being included in the snow.

I recorded a video last night. It still sums up my thoughts pretty well.

11-13-18 Winter Storm Likely for Wed Night/Thu; Snow and Ice Possible

11-13-18 Winter Storm Likely for Wed Night/Thu; Snow and Ice Possible

A winter storm is looking more and more likely as we get closer to the event. It looks like we’ll see a mixed bag of snow and freezing rain across the Ohio Valley with this setup. The graphic below gives you a general idea where each precipitation type MAY setup. This will likely need adjusted as we get closer. Areas right along the border of each zone should know that it could go either way for you. This is a tricky storm to forecast because a temperature difference of just a degree or two will make a world of difference in what you see!

Here’s how hi-res future radar looks right now. It looks to start initially as rain on Wednesday afternoon. By late evening, we should start to see a transition to snow and ice across the area. This lasts through the overnight hours into early Thursday morning. Could be a pretty rough commute coming our way on Thursday as you get up and head to school/work. The precipitation works northward and we’ll dry out considerably for the afternoon hours on Thursday. Just a few lingering snow showers across the area.

Every model sees this now, but there still some differences on placement. In general, Southern Illinois stands the best chance of seeing all snow. And it could be a heavy snow event there. Some of the data does take that heavy snow into Southwest Indiana, as well. It will be a mainly ice setup for Southeast Indiana and much of Kentucky, ending as rain or light snow showers. Areas that see the ice rather than snow will likely warm up to the mid to upper 30s on Thursday, so road conditions will improve as the day goes on. Could be a tricky morning commute, though.

Here’s what the data shows this morning. Hi-res NAM snow totals:

Hi-res NAM ice:

GFS snow:

GFS ice:

The new test GFS snow:

Test GFS ice:

Canadian snow:

Canadian ice:

A quick glance at those will show you that the exact track still has to be fine tuned. That should be able to be done tomorrow morning. Every models shows snow on the western side of the storm and ice on the eastern side. Where that cutoff between snow and ice goes is the issue right now. Heavy snow is very possible in the snow zone. This upper Low means business! Some areas could see close to a half foot of heavy, wet snow out of this. Best idea for that right now is Southern Illinois. I do suspect areas around Evansville could get in on the snow action, too. Amounts and areas will hopefully be better focused tomorrow.

Stay tuned for more updates!

11-9-18 Flurries Tonight, Accumulating Snow Next Week?

11-9-18 Flurries Tonight, Accumulating Snow Next Week?

The well below normal temperatures are on their way to the area. The rain has moved to the east and a few snow showers are working their way through Illinois as I type this at the Noon hour. Those will work their way into Southern Indiana this evening. It won’t amount to much and not everyone will see snow. But a few might see a light snow shower or a few flurries. These will likely arrive after dark.

We’re dry and cold for the weekend. We’ll drop to the low to mid 20s tonight and then look for highs not making it out of the 30s on Saturday. We don’t rebound all that much on Sunday. Cold weekend coming.

Rain then arrives on Monday before changing over to snow showers on Monday night. All of the models now show this, but there is still a bit of disagreement on the placement and amount of snow. Here’s where the data stands as of this morning.

GFS has slowly been correcting back to the northwest. Yesterday it had this as an east Kentucky event. I expect this to continue correcting farther northwest. This is a typical GFS error this far out. The GFS is the outlier in this, as all the other models dial in on Southern Indiana.

The new test run of the GFS (called FV3) is much more northwest and delivers a nice hit of snow for Southern Indiana.

The Canadian model has held consistent with a nice hit of snow for us the past couple days.

The European model has been pretty consistent with a similar idea to the Canadian, only with lesser amounts of precipitation.

The NAM does not see this far out yet, as it’s a shorter term model. However, the angle of the precipitation on the last frame of this run looks to be in line with the Canadian/Euro ideas with a hit for Southern Indiana.

The moral of the story? All the data lines up well for a bit of light snow to come to the region on Monday night and Tuesday. The timing and amounts vary, but that’s typical this far out.

GFS has light totals for the area.

Canadian model is much more robust with the snow totals.

The new test FV3-GFS is also pretty robust with snow totals. It’s much faster with the transition to snow, hence the heftier amounts. Can’t rule this out, but it’s not the most likely solution.

I’m not sold on those robust totals yet. We are still three days away, but I show them to you so you can see there is a wide variation in the data. Over the next 24-48 hours, we should start to see these models come into pretty good agreement. This much I will say: I would not be shocked at all for someone to see a nice swath of 1-3″ of snow out of this. It’s not going to be a huge snowstorm most likely. We’re not talking a foot of snow here. But an inch or two of snow can certainly cause travel problems. We could be in for a rough Tuesday morning commute if this verifies.

After this cold snap is over, look for temperatures to moderate some. We wont’ see this extreme cold last all month. Ensemble data does suggest we stay cooler than normal the rest of the month, but the extreme cold doesn’t last more than a week.

Raw numbers for Evansville show this well. We’ll stay cold for a bit, but a return to the low 50s still looks possible closer to Thanksgiving.

Here’s my latest 7 Day Forecast. If you haven’t brought in the garden hoses and winterized your property yet, now would be a good time. Some very cold temps are coming at night the next several days!

Going forward, the Arctic Oscillation looks to stay in the negative for the most part through December. A -AO like this tends to favor colder weather for us. So while we’ll moderate out of extreme cold, I wouldn’t look for major warmth to come. A near normal to likely below normal pattern will probably take hold for the next few weeks.

Cold and Wintry Look Lies Ahead for the Next Week

Cold and Wintry Look Lies Ahead for the Next Week

Get ready for some very cold weather over the next few days! Tomorrow will be the last “warm” day for awhile. Looks for highs in the upper 40s tomorrow, with some very cold rain showers arriving late Thursday evening. This should stay all rain for Southern Indiana, but just to our north around Indy and northward, they will see their first snow of the season out of this tomorrow night. Future radar below shows this well.

Cold air will rush in behind the cold front and we may see a few snow flurries of our own here on Friday late evening. Not looking for any accumulation here. Just some flurries. And not everyone will see these, but a fair chance some of us will and maybe more than is shown here. Cold air can’t hold as much moisture and the energy that will dive in with this system can oftentimes find a way to squeeze out some moisture that the modeling doesn’t see.
 
A very cold regime then moves in for the weekend. We’ll plummet to the mid 20s by Saturday morning and likely not make it out of the 30s for highs on Saturday. The weekend looks dry, but very cold.
Then a big storm system looks to arrive early next week. That one has lots of questions with it. The Euro brings a very deep trough into the region. A deep trough like this would likely suppress the system far to our south and then veer it up the east coast.
Another run of the Euro isn’t quite as deep with the trough and gives us a risk of some rain and/or snow with it. So right now, it’s low confidence as to the precipitation and high confidence on the cold. The question is how bad the cold will be and if we see any precip with it.
Last night’s Euro really likes the idea of rain and snow for us early next week.
This morning’s Canadian likes the idea too.
This morning’s GFS likes the idea of suppressing it to our south.
What do I think? It’s just too early to tell. It will all depend on how deep the level of cold that is coming is going to get. If the trough digs deep and we get really cold, it goes to our south. If the trough isn’t as deep and the cold is cold, but not ridiculously extreme, then we’ll have a storm of some sort. Right now, we just need a few days to figure this out. It’s a week away, so you can be guaranteed that the modeling does NOT have a handle on it and likely won’t until Saturday and beyond.
Either way, it’s going to get mighty chilly. Get your winter clothes out of storage, you’ll need it! More updates to come as we get closer. Stay tuned.
4-4-18 Accumulating Snow Possible Friday Night

4-4-18 Accumulating Snow Possible Friday Night

Welcome to Sprinter!

I hate that I even have to be typing up this blog post. It’s April 4th. Snow should be long done. The average high is 66° today. And yet, here I am talking about accumulating snow for Friday night. Please don’t shoot the messenger! I’m not thrilled abut it either and I’m a snow lover. Just not a snow lover when I’m ready to be gardening and seeing 70s…

To start off, I can’t give you definitive numbers on snow totals coming just yet. They vary too widely on the modeling and we’re still two days away. But here’s the general idea of where I think the accumulating snow is likely vs. possible. The blue shading is where I think the best chance of seeing at least an inch or two is. Modeling gives much more than that for some areas right now. Still need time to dial those in.

Here’s the way the GFS shows this. Look for the rain showers to change to snow showers after dark Friday evening. The snow is mainly an overnight event for us. Gone early Saturday morning.

NAM is very similar.

The Canadian and Euro are also similar, but I won’t show them here to be brief. As for totals, here are the past few runs of a couple models.

Past 6 of GFS

Past 2 of NAM. It’s just now coming into view with this system since it’s a short-term model.

Past 6 of the Canadian. It’s been very erratic, but the snow idea is there. Can’t really use it just yet to pin down anything, other than to say that it sees this system.

For what it’s worth, NWS has a 10-40% chance across the area for AT LEAST 4″ of snow Friday night.

Bottom line: accumulating snow looks highly likely for someone in the Lower Ohio Valley on Friday night. At least parts of Southern Indiana should see some of this. There will likely be a swath of 1-3″ of snow, but pinpointing where that goes is the task for the next two days. Some may get a 2-4″+ swath, but it’s just too early to tell right now. So keep checking back for updates. Travel on Friday overnight and Saturday morning will probably be a big mess. On the bright side, it should begin to melt pretty fast. Here’s my latest 7 Day. You can see it won’t stick around long!

4-3-18 Severe Weather Outbreak Possible Tonight

4-3-18 Severe Weather Outbreak Possible Tonight

SPC has now upgraded most of the area to a MODERATE RISK for severe weather this afternoon and early evening. To put that into perspective, Moderate Risks are only issued when there is pretty high confidence that a major severe weather event is going to unfold. It’s looking increasingly likely that we could possibly see an outbreak of severe weather tonight. Damaging winds, large hail and strong tornadoes are all on the table right now.

Here’s how future radar looks right now. The polygons in the individual cells are rotation tracks. This is a very concerning look this afternoon. We may see two rounds of severe weather. One may come early afternoon in the form of supercells ahead of the main line of storms. Those could be prolific tornado producers if they get going. Those are a little less certain, thankfully. The second, and main, round comes late afternoon through early evening. That will be a broken line of storms that will be capable of all modes of severe weather. Best timing for that line is from 4-8pm across the state.

Here are the risk from the latest SPC update. Tornado:

Wind:

Hail:

The hatched areas in each of these graphics indicate where the most significant threat for each of these would likely exist.

Right now at the Noon hour, we have a pretty strong cap across the area. That’s what I’ve circled in black below. If we can get that cap to hold a little longer today, we will likely see explosive storm growth this afternoon when it breaks. Think of this like holding a lid over a boiling pot of water. Once the lid is off, the steam erupts from the pot. Once the cap is broken, all hades may break loose tonight across the area. Make sure you have a way to get warnings and stay tuned to the forecast this afternoon. It’s almost a near certainty that we will go under a tornado watch at some point later this afternoon. Keep it tuned to Southern Indiana Weather on Facebook and @WilhiteWx on Twitter for more frequent updates.

 

 

 

 

 

 

 

4-2-18 Severe Threat Increasing for Tuesday Afternoon

4-2-18 Severe Threat Increasing for Tuesday Afternoon

Severe weather is looking increasingly likely as we go through the day on Tuesday. SPC now has an ENHANCED RISK for severe weather that covers most all of Southern Indiana and pretty much all of Western Kentucky, too. Damaging winds to 70mph or higher could be common with a squall line that will plow through the area very fast on Tuesday late afternoon/early evening. There will also be a tornado risk with this setup.

Here’s the way future radar plays this out tomorrow. It does try to pop a few discrete cells ahead of the main line. If that does happen, it could be a very bad setup. We will likely have a very strong cap in place tomorrow, though, so I’m questioning just how much would pop ahead of this line. I really think at this point that the main threat will come with this line as it rolls through.

There will be plenty of wind energy to work with tomorrow. Notice below that the direction of those winds change as you go up in height. That little bit of spin in the atmosphere could allow for some tornadoes to develop along this line as it moves through. Also notice that there will be some instability tomorrow. While it isn’t huge, it’s still early spring. We don’t need a lot this early in the year for severe storms to fire off. In short, it looks like plenty of fuel for these storms to fire tomorrow.

The spin in the atmosphere can be measured by something we call the Energy Helicity Index. And you can see below that, while it’s not off the charts high, it’s certainly elevated. Plenty of spin for these storms to possibly start rotating.

The Significant Tornado Parameter index is also elevated tomorrow, especially along the line. Watch out for bowing line segments on the radar tomorrow afternoon. These will be the ones that we’ll have to worry about for a tornadic threat. While these tornadoes would likely be brief spin-ups, even brief ones can do a lot of damage.

With the severe weather ingredients looking this good right now, I wouldn’t be shocked if we see a Moderate Risk upgrade for tomorrow. We shall see. I’ll have more updates as more data comes in. Look for a video to detail the threat later this evening.