Saturday, January 31, 2009

1/31 - 4pm - New Video Forecast

After a warmer weekend, chilly weather sets in for the beginning of the workweek. A snowstorm that was forecast to hit us on Monday has now veered off to the east, so we won't see any problems with snow next week. Warmer weather should set in by Thursday.

Friday, January 30, 2009

1/30 - 4:30pm - Models Having Difficulties

The models I mentioned earlier are still going way off to the east with this Monday storm, except for the NAM now:



That's a definite westward shift from earlier runs of the NAM, so we'll see if this spreads to other models. I still smell something fishy. The way that just about every model shifted this storm way off to the east in one model run really doesn't make sense. I think we'll see flip-flopping over the next few runs, but the easterly solution that the GFS and ECMWF are portraying probably won't stay. We'll have to see if this reverts back to where we were last night or if this stays just to our east.

For the time being, we'll warm up tomorrow into the 30s and into the mid 40s on Sunday. LG&E is now reporting 174,000 without power, which is up a bit due to trees falling in the wind and other factors. I've been listening to the Mayor's press conference, and he's really emphasizing safety with generators and carbon monoxide problems. Remember: Do not use generators or grills inside your house or garage. Keep those appliances away from your home and windows to avoid carbon monoxide poisoning. There have been fatalities in the area due to carbon monoxide, so be very careful if you are using a generator or other similar appliance. There probably aren't very many people reading this blog who do not have power (unless on a mobile device), but pass this information along to those who don't have power if you can.

1/30 - 10:15pm - Monday Snow Going East?

The latest GFS, NAM, and even the ECMWF (Euro) are taking our storm on Monday well to the east now. It's strange how all the models changed at once last night with this shift. I'm not sold on the far eastern track that it's taking, but I'm beginning to think that the models I posted yesterday are too far west. We'll see how this shapes up today and tomorrow.

The latest numbers from LG&E show that 172,000 are still without power and 11,329 lines are down. Still looks like 7-10 days before everyone gets power back.

Thursday, January 29, 2009

1/29 - 9pm - Monday Looking Increasingly Interesting

First off, LG&E is reporting 190,000 without power right now. This is up a bit from last check due to more trees falling as the day went on. For a map of the current power outage estimates in Jefferson County, click here. A state-wide map can be found here.

On to the next storm, which could be a whopper if things fall into place. An area of low pressure surging north from the Gulf of Mexico should cool things down on Monday from the near 50 degree temperatures we'll have on Sunday. The accompanying precipitation with this storm will be impressive to say the least, maybe even historic. Here's the latest model outputs:


18z GFS


12z ECMWF (European)


18z DGEX

Notice how all three of these models offer a similar track for the intense low, which is west of where it was forecast to go yesterday. The Canadian (posted yesterday) looks about the same, but has shifted west slightly. You're probably looking at the darker greens and blues on the GFS and DGEX and saying "Uh-oh." I'm saying the same thing. Look at this preliminary accumulation estimate taken from the GFS for this storm:



Yeah, that's 6-8" at a 10:1 rain/snow ratio. Here's the problem: we'll be operating at a ratio that could get higher than 12:1 during the coldest part of the storm, when the freezing line at the surface sinks way south of here. These totals could be nearing 12" if that happens.

We're still four days away, so things could change. The daunting issue is that the models are agreeing on this storm pretty well. I think there is a chance that it could correct eastward, but I'm only seeing westward trends at this point. If this low track changes slightly and pulls up more moisture from the Gulf, we could be dealing with a historic storm. It will be interesting to see what happens. Again, whatever happens on the models this weekend will be the deciding factor on whether Louisville, Lexington, or somewhere further east gets the brunt of this storm.

1/29 - 12pm - A Snow-Covered Morning

The latest numbers put Louisville at 183,000 without power. That's an improvement, but still a very high number.

The latest GFS still has that storm on Monday giving us quite a bit of snow. The Canadian is still doing the East Coast solution with little snow, but all the other major models are going more westerly with more snow here. Could this really be a second storm for us? We should know this weekend.

Wednesday, January 28, 2009

1/28 - 11pm - New Power Outage Numbers

LG&E is now reporting 205,000 customers without power in Louisville. That is way up from the estimate of 100,000 this afternoon. I'm surprised that I have power right now, especially after I lost power last night for a few hours.

1/28 - 7:30pm - A Cold Night for Many

As night descends on a city where many are without power, a low near 10 degrees does not sound good at all. This will be a rough week and weekend because temperatures will not even break the freezing mark until Sunday (when we get into the 40s). A little light snow on Friday will freshen up the snow on the ground across the area, but nothing more than a dusting will come of this. I'm more worried about the winds that could come with this system, topping 20mph in some cases. This could cause more ice-covered limbs to fall, meaning more power outages. I can already tell that "snow" has become a four-letter word around the area, with the word "ice" rising to a whole new level of vulgarity.

Whether you like snow or not, there is a possibility for a snowstorm on Monday. The GFS and DGEX are showing a storm in here during the day on Monday and lasting into Tuesday morning:


18z GFS


18z DGEX

I've been watching this develop on the models for a couple of days now and it's been fairly consistent. A little ray of hope for those who dislike snow is Canadian model, which is taking the brunt of this storm to our east:


12z Canadian

At any rate, I don't think this storm will harbor any ice due to the relatively cool temperatures forecast to be present at 850mb (5000 feet). This is certainly a storm to keep tabs on through the weekend.

1/28 - 4pm - JCPS CLOSED REST OF THIS WEEK

Jefferson County Public Schools will be closed for the rest of this week according to media reports. As many as 67 schools are without power at the moment.

1/28 - 1pm - A Wild Storm Comes to an End

The snow and ice are out of here, but the region will be dealing with power outages and tree damage for quite a while. Temperatures are steadily dropping across the area, with 25 degrees at my house right now. The interstates are passable, but side roads and county roads are treacherous if they have not been plowed. Tree limbs on roads are also causing quite a few problems as well.

Here's what it looks like in my neck of the woods:



Since temperatures will not get above freezing until at least the weekend, the trees are going to look sickly for quite some time. My neighborhood roads are terrible, but it's not impossible to drive on them. This is one of those days where an all-wheel-drive or 4-wheel-drive vehicle will come in handy.

UPDATE (1:15pm): LG&E is now reporting 100,000 without power in the Metro, with KU reporting 176,000 outages throughout the state.

1/28 - 10:30am -Tree Branches are Falling!

I was taking video outside when a tree branch fell in the woods. You can't see the actual tree branch fall, but the sound in itself is enough to send shivers up your spine:

video

Everyone needs to be on alert for falling tree limbs today, especially if you have to drive this afternoon. The weight of the ice on the trees is getting to be too much, along with added weight from the snow.

1/28 - 9:30pm - Power is Back!

Our power was restored early this morning, so I'm back online for the day.

The snow is falling hard out there, with temperatures dropping rapidly. We were at 31 about a half hour ago and now we're at 28. This is around the temperature for a flash freeze, so any standing water left over from last night will freeze. The ice from overnight has the trees looking sickly and many without power. 75,000 LG&E customers are without power right now with 125,000 KU customers without power as well.

I just took a look at the TRIMARC cameras around the area and the interstates look snow and ice covered. They're passable, but not good at this point. I would recommend staying home if at all possible. There have been just under 100 accidents on the roads since midnight.

I think everyone will end up with 2-4" of snow as forecast. The tale-end of this system is approaching the area, but I think we have up to an hour more of heavy snow. After the heavy snow ends, we're done with this storm.

Tuesday, January 27, 2009

1/27 - 11:43pm - Power is Out

Via cell phone... The power has gone out at my house. No more blog updates tonight. Sorry!

1/27 - 9:10pm - Everything is on Track

Not much has changed since I posted the video update earlier. We're holding just below freezing here in Louisville and I think we could go up to 33, but no more. This won't hurt our snow chances tomorrow and really won't help the nasty freezing rain situation tonight because the rain will still accumulate on already icy surfaces. My previous warning about power outages still applies. Reports of tree limbs snapping around the area are becoming more numerous as the night wears on. Roads should be OK until early tomorrow morning, when the fun begins.

I think we'll get 3-4" of snow by mid-morning tomorrow, but there could be more. The 0z NAM hints that the 0 degree line at 85omb will be east when we get a nice slug of precipitation totaling .5" to .7" of liquid. Do the 10:1 conversion and you've got 5 to 7" of snow. I'm not saying that there will be 5 to 7" of snow tomorrow, but we certainly could get more if the warm air hightails it out of here earlier than expected (which is around 5am at the moment).

Since JCPS is closed, I'll be here late tonight to report any changes in the forecast.

1/27 - 9pm - JCPS IS CLOSED TOMORROW

The announcement just came over the airwaves that JCPS is closed tomorrow. This comes just after their participation in an NWS Louisville conference call at 8pm.

1/27 - 7:15pm - Beware of Power Outages

The power has been flickering on and off at my house near Fisherville for the past hour. Numerous reports of the same are coming in from areas all over town. With hours of freezing rain left, prepare for widespread power outages tonight in Louisville and points north.

Again, this freezing rain will stick around until late this evening before changing over to heavy snow tomorrow morning.

1/27 - 3:30pm - Quick Video Update

Here's a quick video update on the storm for tonight and tomorrow:

video

We're going to have to watch this system closely tonight. Any unexpected movements may produce a mess in places where this was not forecast to happen. I read the 12pm update from the NWS Paducah office and they're watching a possible southern shift in the freezing line in that area. We'll see if this happens out here.

1/27 - 10am - That Was Only a Preview

Here's what it looks like at my house:


(I don't think my sister will be riding her scooter today!)

If you haven't gone out and tried to get a handful of this stuff, you should. It's very thick and difficult to even pick up; This stuff is not good for sledding. Tomorrow afternoon will be a better time to go sledding once more snow gets in here early tomorrow morning.

But first, a dangerous ice storm is on the way from Arkansas:



This will be here by the mid to late afternoon hours spreading quite a bit of freezing rain and sleet across the area. If this gives us mostly freezing rain, then be prepared for some power outages. I think we could get .25" of ice accumulation, which is pretty bad, but not disasterous. Here's a video of Jim Cantore from The Weather Channel talking about this storm in Paducah... click here.

After the ice is done tonight, more snow is on the way. The NAM and GFS both show a pretty potent area of snow coming through early tomorrow:



From these two models, I'm thinking that the area will generally get 3-4 inches of snow tomorrow morning. Isolated amounts of 6 inches are possible as well, so that should give us better sledding conditions.

Interstates are beginning to improve a little bit after the mess earlier this morning. Use caution if you must go out today.

1/27 - 6am - What a Mess!

Good morning! Since JCPS is closed, I thought that I'd post an early morning update.

First off, don't drive if you don't have to today. Snow and sleet totals around the area are in the 2-3" range around town and we are far from finished. We got mostly sleet in the Metro, but that mixed with the snow is making for a nasty layer of gunk on the roads.

Temperatures at 850mb (5000 feet) are going to rise today, changing our sleet and snow to freezing rain. I'll be blunt: We are going to see a major ice storm tonight with this changeover. This is the kind of precipitation that knocks out power and downs trees. Temperatures today will most likely stay just below freezing, so don't expect things to get much better before we descend into part 2 of this storm. Temperatures at 850mb will cool later tonight, which should change the freezing rain to snow. Expect another 2 inches of snow by Wednesday morning once this happens.

I've been watching the local morning news shows and the live shots they're broadcasting from the interstates are quite interesting. I didn't think the interstates would get that bad this morning, so please be careful if you have to be on the roads.

Monday, January 26, 2009

1/26 - 9pm - Video Update

Here's the video update... everything is coming together on the radar quite well at this point.

1/26 - 4:30pm - More Ice, Less Snow

WINTER STORM WARNING - 10pm tonight until 1am Wednesday.

Here's how things stand at the moment for tomorrow during morning rush hour:



I think the heaviest snow will be just north of Louisville, with temperatures staying just below freezing at the lower levels up there. Here in Louisville, I expect 3 to 4 inches by tomorrow morning. This is down just a bit because I think we'll transition to ice earlier than previously thought, meaning some of that 3 to 4 inches will be sleet on the ground. We could pick up another inch of sleet and snow throughout the day on Tuesday before the snow picks up again on Tuesday night. I'm thinking we'll have another inch or two of snow out of that by Wednesday. The total snow/sleet accumulation for Louisville should top out at around 5-6 inches by the time Wednesday morning rolls around. Points south of Louisville will see 2 to 3 inches tonight, but a transition to sleet will happen sooner in the morning. Freezing rain in the afternoon down there could trigger dangerous ice storm conditions as well.

Now... if we get even warmer at the upper levels, we'll see lower amounts of snow and more ice. Freezing rain is not out of the question either. The general gist is that we'll see more sleet, but snow should be the dominant precipitation tonight and early tomorrow morning. We should stay below freezing all day tomorrow, but that's subject to change. If things trend colder at 85omb (5000 feet), which I do not think will happen, then expect more snow. Either way, driving will be messy tomorrow morning and there will be numerous school closures.

Sunday, January 25, 2009

1/25 - 8:30pm - Quick Snow Forecast Update

The models have been going a bit to the north with this system over the course of today, meaning we'll see some sleet and maybe freezing rain. We're still looking good for 5 inches or so, but the amount of ice on top of that is increasing with each model run. The heaviest snow will fall just to our north in Indiana, with 8 or more inches there. If we start seeing colder temperatures at 850mb in the model runs tomorrow, we're in for some heavier snow. For now, I think this will be a moderate snow event tomorrow night with an icy mess on top by Tuesday afternoon. We're still on for a little bit of snow on Tuesday night and Wednesday morning as well, so an inch or two could be appended on to the current 5 inch estimate. There's still plenty of time for things to shift tomorrow, so keep up to date!

1/25 - 1pm - WINTER STORM WATCH

The National Weather Service has issued a Winter Storm Watch for the area starting tomorrow night. At this point, I think we're going to get more ice than previously thought. Snow accumulations should total up to around 5" in the Metro by Tuesday evening, with ice accumulations of .25" or higher. Having just one of these components is bad enough, but having both will make conditions worse.

The reason for the enhanced ice is a warm layer of air a few thousand feet up that will come from the south on Tuesday afternoon. This is called an overrunning event. Surface temperatures will stay below freezing, but liquid precipitation will fall and freeze either on the surface (freezing rain) or just before it hits the ground (sleet). Here's how the 6z GFS played out with this:

Click any image for a larger view.

On the surface chart, the 0 degree line stays near the KY/TN border on Tuesday morning, meaning below freezing temperatures at the surface.


On this 850MB (5000 feet) chart, the 0 degree line is just south of Louisville, and should go slightly north of the city by Tuesday afternoon. The longer this line stays north of here and surface temperatures stay below freezing, the more ice we get.

The NAM model is going colder with this storm, suggesting all snow for us. I don't know if I buy that because it seems to be portraying an outlying solution compared to the GFS and Euro. With that in mind, I still think we'll see 4-5" in Louisville by Tuesday afternoon, with a fairly thick layer of ice to top that off. More snow is possible on Tuesday night and Wednesday morning, but I don't think we'll see more than an inch or two from that. Southern Indiana will get more snow than ice; Central and Southern Kentucky will get more ice than snow.

So, we're dealing with a mixed winter storm at the moment. If the 850MB charts change, we'll see either a larger snow portion or a larger ice portion of this storm. Either way, it's going to be a mess. I'll post tonight if anything changes in the models.

Saturday, January 24, 2009

1/24 - 5pm - New Forecast Video

Looks like we're going to see our first major accumulating snow of the season next week! As an area of low pressure passes to our south, snow will overspread the area on Monday night and Tuesday. At this point it looks like more than 4 inches is possible, but a little bit of sleet on Tuesday could limit those accumulations slightly. A system coming through on Wednesday and Thursday could also bring some snow, but it looks like more of a rain-maker at the moment. Any shift south in that storm's track would likely bring us all snow. Stay tuned throughout the weekend!



EDIT (6pm): The 18z GFS is giving us all snow for both systems now. I'm upping my estimate to 5+ inches, with amounts up to 8 inches possible. The HPC is also putting us under a MODERATE Risk of 4+ inches of snow and a SLIGHT Risk for 8+ inches of snow.

Friday, January 23, 2009

1/23 - 4:45pm - Snow Shovels?

I think we may need to use snow shovels on Tuesday. After taking a look at the latest GFS runs, they've started going toward the HPC's solution of the low passing to our south. This means we'll see all snow on Monday night through Wednesday morning if this track holds. Snow amounts are tricky right now because the 6z GFS had us getting pummeled with quite a bit of moisture, but the 12z backed off. This will vary over the next couple days, so we needn't worry about snow amounts yet.

The Wednesday-Thursday storm looks like rain to me at the moment, but I'm still going to keep an eye on it. If the next storm corrects southward on the models like the one for Monday-Wednesday, look out. Obviously none of this is set in stone, so we'll have to wait for successive model runs to determine the details. I've have more details in the video forecast tomorrow afternoon!

Enjoy the last of the warm air this evening! Temperatures in the 30s are in store for the weekend after this cold front passes tonight.

Thursday, January 22, 2009

1/22 - 5pm - All Over the Place

There's a word I like to hear when we have a storm in the forecast: model convergence. I haven't heard it or said it once today. This system next week that could bring us a ton of snow, a nasty ice storm, or a boatload of rain just cannot be forecast accurately at this point using our 21st century technology. The GFS gives us a smattering of snow on Tuesday before cranking up the rain for Wednesday and Thursday. I'm getting a similar gist from the Euro as well.

I just looked at the HPC's low track and they have the low tracking through Tennessee. The DGEX model seems to agree with that to some degree. The thing I've seen the most on all of these models has been a depletion of moisture on Monday and Tuesday to the storm (two systems going on here) on Wednesday-Thursday. I also noticed that the Louisville NWS is sticking to their guns with an all snow solution for both systems on our local forecast package, although they note how difficult they are being forecast-wise. I think we'll know by Sunday if we're going to get socked by this thing or not. Don't get your hopes up.

What I can bet on is warm weather for tomorrow! After a high in the 50s today, we'll see mid 50s for tomorrow. The reality of Winter will set in by the weekend, with lower 30s for both Saturday and Sunday.

Wednesday, January 21, 2009

1/21 - 7:30pm - Still Watching Next Week

I think most of us are ready for a break in these cold temperatures around here! Luckily, both tomorrow and Friday will rise into the 40's and maybe touch 50 for a high temperature. There could be a few sprinkles of rain on Friday as well, but overall not an active weather pattern for late week and the weekend.

Next week is still looking ominous and complex. The fact that somewhere in the region will see a moderate to major ice and snow event is pretty much agreed upon, but where is the real question. The GFS has trended slightly colder and further south over the course of today, but we'll see how that works in the 0z tonight and subsequent runs tomorrow. The Euro is similar, but wants it to come through slower. At any rate, nobody really knows if this will be a mix (my bet), all snow, ice, or rain for us.

The GFS has waffled around with precipitation potential today as well. Earlier runs had a moderate amount of precip, but the 12z and 18z sucked alot of moisture out of the area. I really wouldn't lose sleep over that fact at the moment because it's too far out. I'm unsure if the low precipitation bias on the GFS still exists, so we'll have to see how this acts on the models. There's a possibility that this could be an ice storm or snowstorm, so everyone needs to keep up with the latest forecast.

Tuesday, January 20, 2009

1/20 - 7pm - Another Week of Snow Forecast Drama

It's cold. We hit 27 degrees for a high today and most of the snow has melted. President Obama's inauguration in Washington had about the same weather as we did, so you can bet it was uncomfortable to be among the crowds in attendance. A warm up is on the way, but a storm lurking in the shadows will cause quite a stir in the forecast.

Tomorrow will nudge above freezing for a high and temperatures should top out in the mid 40s for Thursday and Friday. The models continue to show a couple snow showers around for Friday, but they won't be anywhere near the magnitude of Sunday night's snow event. Temperatures will hold below freezing for the weekend with sunny skies.

Then the "fun" begins.

I've been watching this Monday-Wednesday storm for a couple days now. Over the weekend it looked impressive, but I didn't like where the models were taking the area of low pressure. Yesterday we saw a southward shift in this storm, which piqued my interest and made me a little more optimistic.

Today we saw more southern movement on the models, especially in the GFS. That prompted the Louisville NWS office to put this statement in their forecast discussion:

FORECAST CONFIDENCE ON HAVING A MAJOR PRECIPITATION EVENT IS ABOVE AVERAGE. HOWEVER...THERE ARE MAJOR QUESTIONS REGARDING THE OVERALL THERMAL STRUCTURE WHICH WOULD RESULT IN DIFFERENT P-TYPES. WE WILL BE RAISING POPS SIGNIFICANTLY FOR MON-TUE AND FOR NOW WILL SIMPLY MENTION A MIX OF RAIN/SNOW AND ADDRESS THE ONGOING P-TYPE ISSUES IN LATER FORECASTS. STAY TUNED!

After looking at the 12z and 18z GFS, I agree that this will be very difficult to pin down in terms of precipitation type. Right now this looks rather icy for us, but a slight shift south would give us quite a snowstorm. Then again, it could shift north and become a rainy washout. To illustrate how close we are to the freezing mark, here's the surface pressure map from the 18z GFS for late Monday night:



That blue line straddling the Ohio River is the freezing line at the surface, which is a stone's throw away from town. This line along with the low was south of here for the duration of the storm on the 12z GFS, but the 18z (one above) took it just a hair north of town. I also noticed an increase in precipitation in the 18z as well, so we're really going to have to watch this one. My best guess right now is a mix of ice and snow. It's too early to call for snow amounts (if any) at the moment, but that looks like the task at hand for this weekend. This should be interesting!

Monday, January 19, 2009

1/19 - 10am - We Finally Got Some Snow!

It was snowing pretty hard until just after midnight across Jefferson County. A second batch of snow showers came through around 3am this morning and gave us our final batch of snow for the morning. We got exactly 1 inch at our house this morning, which nearly covered up the grass. Here are some photos:



There is a chance for a few more snow showers today and tonight, but I don't think they'll be as strong as last night's. High temperatures will stay in the 20s for today and tomorrow, but should warm up into the 40s for late week.

Sunday, January 18, 2009

1/18 - 8pm - Have You Seen the Radar!?

I've been peeking at the radar over the past 3 hours, and boy how things have changed. A small area of snow showers in Illinois has exploded into a well-developed line of light snow heading straight for us:



I'm thinking about an inch should come out of this, but if more explosive development occurs I think we could see a little more. We're not talking about a snowstorm, but I think the ground will be white by tomorrow morning. Local temps around the area right now...SDF 31...my house 31...LEX 30...EVV 32...CVG 26...IND 21. It's cold enough, so maybe this is finally our chance to get the ground covered with snow! I noticed that brine is on the roads around the Metro, so travel won't be too bad. Watch for low visibility during heavier snow showers though.

Saturday, January 17, 2009

1/17 - 3pm - New Video Forecast

Looks like a clipper system passing to our north will provide some light snow tonight through tomorrow evening. Accumulations will be mainly under an inch with this system. We could see more than an inch if temperatures stay below freezing tomorrow and more moisture is pumped into the area. Temperatures will moderate by the middle of next week.

Friday, January 16, 2009

1/16 - 4:45pm - Get This Cold Air Outta Here!

I wanted to go back to sleep after our weather station displayed this at around 6am this morning: -3.7°F. Yikes! Temperatures in the city held at -1 for a couple hours this morning before shooting back up to 17 this afternoon. It really doesn't matter if it's -1 or -3, it was downright cold anyway!

Tomorrow will feel like Spring compared to today, with a high around 40 after a low tonight of around 7. As that clipper approaches, temperatures will drop to near freezing for Sunday.

The computer models have been getting a little more aggressive with the clipper tracking north of us on Sunday. Right now, I'm seeing around an inch of snow on the GFS and NAM, with pretty decent agreement on track and temperature at the moment. We'll have to watch this, but I think this is a pretty solid forecast based on the track of the last few clippers this week.

Thursday, January 15, 2009

1/15 - 4:30pm - ZERO

The number zero will be popping up on thermometers across the area tonight as this cold trough sticks around. I think the inner-city areas will stay a touch above zero, but I think the rest of town will get down to zero or very close to it tonight. Wind chills will be near -10 (Wind Chill Advisory in effect), so bundle up tomorrow morning as you head out. Tomorrow's high will be a degree or two cooler than today, so we should end up around 16 by the afternoon.

A warmer weekend (if you want to call this warmer) is in store, with the possibility of barely getting above freezing. It still looks good for a few flurries on Sunday morning, but I think we'll be moisture starved for at least the early part of next week. Warmer temperatures should return by that point as well.

Keep those hats and gloves on!

Wednesday, January 14, 2009

1/14 - 5:30pm - Courier-Journal Article, A Little Snow

I was featured in the Southeast Neighborhoods section of the Courier-Journal today, click here to read the article. Also, they did a short video montage of how I do my videos and what my normal Saturday afternoon is like:



Snow is on the way in the next half hour as a small batch of heavy snow comes through from Harrison County. Temperatures will drop significantly during and behind this small area of snow, so we could pick up a dusting or so. We're around 40 right now, but 20s are easy to find as you go west of here, especially in St. Louis.

The cold air behind this system will be intense, with a high of only 15 tomorrow! We'll recover a little bit this weekend, with highs getting just above freezing and the possibility of flurries.

Tuesday, January 13, 2009

1/13 - 3:45pm - Cold Air Settles In

The morning rush hour and the rest of the day were spared from icy conditions due to a later passing of the cold front this morning. Limited backside moisture also decreased the amount of snow showers we saw as well. Overall, we were pretty lucky that the front didn't come through earlier and cause a flash-freeze situation on the roads.

Our next clipper system comes through on Wednesday afternoon, giving us a chance for a little more snow throughout the afternoon and evening hours. Since the low will be tracking north of the area, don't expect much in the way of accumulation, if any at all. A couple models started putting the storm on a more southerly track last night, but they haven't put it far enough south to make a big difference here. Places north of Indianapolis will see a few inches of snow.

Cold temperatures are staying around for a while, with a high in the mid 30s tomorrow. By Thursday and Friday, temperatures won't even reach 20 degrees for a high! Lows for both of those days will most likely be in the single digits. Stay warm!

Monday, January 12, 2009

1/12 - 7pm - Winter Weather ADVISORY

A Winter Weather ADVISORY has been issued by the Louisville NWS... in effect from 4AM to 1PM tomorrow.

Our clipper system is on the way right now, with rain showers to be falling after midnight tonight. These will quickly turn to snow as a cold front comes through early tomorrow morning. Right now, it looks like this will occur somewhere near the 6AM time period. With temperatures going below freezing at the surface just before that, I think any wet roads will quickly become icy. Snow should top out at just under an inch tomorrow, but we'll see what happens on the radar.

As far as school delays go, I think they're certainly possible given the circumstances. The morning rush after 6-7AM could be dicey with icy roads and low visibilities possible, but there is a little uncertainty as to the exact timing of this. Things should taper off by late morning, so closings are fairly unlikely. As far as who will actually delay tomorrow is unknown, so turn on the TV tomorrow before you head out or send the kids off to the bus stop.

Cold air will filter in behind the front tomorrow morning, so temperatures will drop throughout the day. Wednesday will not see temperatures rise above freezing, and more snow is on the way thanks to clipper system #2. Right now the models take this system well north of here with very limited moisture, meaning a couple tenths of an inch of snow at the most. The possible southward shift and increase in moisture I've been talking about for the last couple of days is getting less and less likely in each model run. Once the cold air comes in to the area tomorrow, we'll see if the models respond with a more southerly track with this system. Generally cooler air will shift a system like this southward, and right now the models take this storm further north than the one coming through tomorrow morning. That seems fishy to me.

So, I'm not sold on a northerly track for Wednesday's storm, but I'm starting to think that might be the solution based on the models. If the models keep with this track by tomorrow afternoon, then I'll throw in the towel with getting any appreciable snow on Wednesday. We shall see what happens.

Saturday, January 10, 2009

1/10 - 3:30pm - New Forecast Video

Temperatures are set to slide later today, but this is only the beginning of an active weather week. Light snow associated with a clipper system will fall on Monday, with a possibly bigger system on Wednesday. The models are handling the Wednesday clipper poorly in my opinion, so we could see more than just light snow. That remains to be seen in any of the computer models, so we'll see how that works out. In any case, get ready for frigid temperatures late next week as a massive trough digs into the Southeast. Highs might struggle to reach the teens by next weekend.

Friday, January 9, 2009

1/9 - 3:30pm - Nice Warm Up Today... Enjoy It While You Can!

After barely getting above freezing yesterday, today's temperatures have felt great. Even though we had some wind in the afternoon hours, 45 isn't too bad for this time of year! Get ready for rain late tonight and into tomorrow as clipper system #1 comes through the region. A few snow showers are possible late tomorrow evening as this system exits the area.

The second clipper will come through on Monday night into Tuesday:


(Click image to see a larger view)

The past few runs of the GFS model have been trending toward rain at the beginning of this system, but as you can see in the 12z run above (at 96 hours out) this will end as some snow on the cold backside. Accumulations will be light, but I think we might be able to squeeze out an inch or slightly more by the time this is done on Tuesday.

Our third clipper will be here for Wednesday night into Thursday:



The models show light precipitation from that now, but I think this might be an underestimate. With a powerful cold front like this coming through and Gulf Moisture present in the south, I'm not sold on the lightness of the moisture that the GFS shows above. Give this one some time... the elements are there for a storm. With the very cold air in place behind this front, rain/snow conversion ratios will be higher (see yesterday's post for more on that).

After these three systems are done, extremely cold air will set in with a mighty trough sinking from Canada. Here's what the Louisville NWS says about it:
SUPER LARGE 1050+ HIGH PRESSURE CELL LOOKS TO DROP SOUTH ACROSS THE PLAINS AND THEN SETTLE SOMEWHERE IN THE SOUTHEAST. THEREFORE...VERY COLD AND DRY WEATHER LOOKS TO BE IN STORE WED/THU INTO NEXT WEEKEND. TEMPS WILL LIKELY BE SOME 25 TO 30 DEG BELOW NORMAL...WHICH WOULD EQUATE TO THE COLDEST TEMPS OF THE SEASON THUS FAR...AND THE COLDEST TEMPS WITHIN THE LAST 10+ YEARS. BRRRR!

Dry weather will dominate with this super-cold air. So, we need to get snow with either the Tuesday or Wednesday clippers before this dry air comes in (that is, if you want snow).

Thursday, January 8, 2009

1/8 - 6pm - The Cold is Coming, Maybe Snow?

Welcome Belski's Blog readers! Be sure to visit ryanweather.org for the full Ryan Weather website.

It's been bitterly cold across the metro today, with a high temperature just above freezing at midnight. We've been falling since then and winds picked up this afternoon, so there was definitely a sub-20 degree windchill to deal with. Temperatures will rise into the 40s tomorrow as an area of low pressure approaches the area. Accompanying this low will be some rain for late Friday into Saturday. Highs for the weekend will stay just below 40 with a few flurries or snow showers possible as the area of low pressure exits the area.

The super-cold air that has been well-publicized over the past week is still coming, but it's up in the air as to when it will really get here. Here's the interesting part: The models are injecting more moisture into this pattern. As I said yesterday, the GFS has a history (at least this season) of underestimating moisture in the long range. A couple clipper systems will come through early in the week, but it's difficult to tell which of these would give us snow. My thinking right now is that the Monday clipper will be too far north to give us any snow, but the Tuesday one might be right on the money for an accumulating snow. The last couple runs of the GFS are delaying the cold air until Thursday, but I still think that's up in the air due to low placement and phasing issues.

Is there the potential for a big storm in all of this? Yes. Do I see a definite large storm in the cards yet? Absolutely not.

The development in the models of this cold pattern needs more time to mature. There was a large storm on the GFS just days ago with the entrance of this cold air on Tuesday, but it has since reverted back into a normal clipper. This is definitely something to watch, especially if a storm like this pops up again with the later arrival of the cold air on Thursday.

At any rate, any snow that falls will be heavier in the upcoming cold air next week due to conversion ratios. Snow at 28-32 degrees has a conversion ratio of around 10:1, meaning for every .1" of rain there exists a potential for 1" of snow. When we have temperatures in the mid 20's or lower, that ratio could go up to 15:1 or higher. That means any weak system could put down some very nice snow amounts! We'll see what happens over the next few days with this cold air and potential snow.

Wednesday, January 7, 2009

1/7 - 4pm - You've Been Warned... Cold Air Coming!

The snow showers were pretty to look at today, but they've not amounted to anything more than a sight to see. Temperatures have hovered near the 34 degree mark, so no accumulation occurred and none was really expected. A small area of snow showers is moving through Iowa and Missouri, with the possibility of coming through later tonight if they hold together. Temperatures will hold below freezing tonight, but don't expect more than a dusting if anything sticks.

Any snow should be out of here by early tomorrow morning at the very latest. Highs will be near 40 for the balance of the week, with rain expected on Friday night into Saturday.

Now... for more interesting things. I'm warning you now, because I've been seeing this on all the models and it looks like its going to happen sooner rather than later. It's going to get very, very COLD next week after a front comes through Monday. I'm talking temperatures not getting above 30 as a high for a week or more starting on Tuesday. It's been a very long time since I've seen air this cold on the models coming down to our neck of the woods, so be prepared. Low temperatures will assuredly sink to single digits with this arctic blast, so keep those gloves handy when you're out and about next week.

Snow prospects for next week are unknown at this point. The GFS have been inconsistent with a system coming through Tuesday and Wednesday, but we will be cold enough for snow at least. The fact that we've at least a little moisture on there for next week is a good sign for some snow because the GFS has been underestimating moisture amounts in the medium and long range as of late. I'll keep an eye on this to see if anything changes.

Tuesday, January 6, 2009

1/6 - 6:30pm - Well, What Do We Have Here?

(This will be a short post... final exams this week to study for!)

First off, the freezing rain thankfully went north this morning. This was not good for areas in South Central Indiana, but it spared the sprawling Louisville morning rush from any problems. We simply were 1 or 2 degrees too high for this to happen.

The 12z GFS shows a possible snowstorm for next Tuesday here, with some definitely cold air coming into the area. The storm was vastly different on the 18z run, with no snow for us. We'll see if we can replicate the snowy solution in later runs tonight and tomorrow.

We won't see more than a few flurries or rain showers tomorrow, so this rain system is pretty much out of here with little consequence to us winter-weather wise.

Monday, January 5, 2009

1/5 - 4pm - Winter Weather ADVISORY

The National Weather Service has placed Jefferson and surrounding counties under a Winter Weather ADVISORY for tonight and into the morning tomorrow. As a storm comes up our way from the south tonight, freezing rain could fall and accumulate on surfaces. While I don't think we'll see more than a tenth of an inch of accumulation, I still urge you to be careful during the commute tomorrow morning. Bridges and overpasses will be the main issue here, but we're not expecting an ice storm or anything close to that severity. Everything should turn to plain rain by late morning. Again, this won't be a big issue, but it bears watching and being cautious.

Rain will continue into the afternoon tomorrow and then turn to snow late Tuesday night into Wednesday. Accumulations will stay under 1 inch and most will probably see a dusting on Wednesday morning, if anything at all. Clear and cold weather will dominate for the balance of the workweek, with rain expected on Friday evening into Saturday.

Looks like we'll see a couple chances for snow next week. Cooler air will be coming into the area, so I think this could be our best shot for snow so far this season. It's too early to pinpoint exactly when we'll see snow and how much, but a couple of systems have been making an appearance on the long range GFS for a little while now. More details to come later this week on this.

Sunday, January 4, 2009

1/4 - 7:15pm - Still Looks Like Mostly Rain

We've seen a slight shift east in the low track for this storm on Tuesday/Wednesday, but it really hasn't had too much effect on our precipitation type. If there were some cooler air to work with, this would have made a bigger difference. We're still generally on the edge of the rain/snow line, but we'd have to see a 100 mile shift southeast in the track of this storm to get to the snow side. All in all, we're still a little ways out, but it's looking less likely that we'll see much snow out of this.

We're still on to see some snow showers on the backside of the system on Wednesday, but I'm not banking on anything more than a dusting in terms of accumulation. There's simply not enough moisture in the cold air behind the system to cause any concern at this point. So, the forecast from yesterday still holds... unless the models start trending east more and giving us more cold air to work with.

It looks like we'll still see cooler temperatures after the passage of this storm, but maybe not as cold as once thought. Still some storms to deal with in the long range, so don't give up if you want snow!

Saturday, January 3, 2009

1/3 - 9pm - New Video Forecast

Sorry about the late video posting tonight... been a busy day!

Most models are still giving us mostly rain for this Tuesday/Wednesday system, but there's still time left for that to change. I'll be monitoring it closely throughout the next few days.

Friday, January 2, 2009

1/2 - 5:45pm - Can I Get a Stable Storm Track Please?

The last 24 hours have been absolutely nuts on the forecast models with our Tuesday storm. Right now I can't say what kind of precipitation we'll see, but I think we'll see a mix of multiple types. Yesterday's model runs showed it to be too warm for any freezing precipitation, but now the area of low pressure is trending slightly east on the GFS and DGEX (derivative of GFS), which starts us out with some wintry precipitation and then goes to rain before a transition to snow on Wednesday. Snow accumulations would be very small, if any, with this solution.

The Louisville NWS office was thinking we'd see mostly rain yesterday, but this trend eastward has made them rethink that. They're saying its unknown what we'll see at this point and would have to be determined based on the low pressure track. I completely agree with that, but all sorts of bells and whistles are still going off in my head.

When I see this kind of variation between the models and their runs at 4 days out, it reminds me of December 2004 and March 2008. We had all sorts of monkey business happen in the models just a few days before those storms, similar to what's happening now. My gut is telling me something is very wrong here and that doesn't happen often. I think we're in for a wild mix of forecasts over the next couple days, but we'll have a correct solution by late Sunday.

For now, I'll stick with mostly rain on Tuesday and a bit of mixed precip at the onset and backside of this storm. BUT, be ready for massive changes in that forecast if the low pressure track goes southeast more. In any case, frigid air is on the way for late next week, but not before a shot at 60 on Sunday!

Thursday, January 1, 2009

1/1 - 2:15pm - Happy New Year!

I'm pulling my hair out at the moment looking at all the forecast models for Tuesday's storm. The GFS has flip-flopped on low placement twice in the last 36 hours and all the rest of the models are playing the same games. Right now I'm leaning toward a mostly rain solution based on a loose trend in the models of the low going to our northwest, but confidence is extremely low in that forecast. The hypothesis that the GFS would correct itself and place the low further north was right, but it put the low too far north for our liking! I think this is the time to sit back and relax while the models play their games and take a closer look at this during the weekend.

In the meantime, we're looking at highs in the 40s through the weekend. Rain will come through Saturday night into early Sunday, with the system I just talked about showing up at our doorstep by late Monday night into Tuesday.

Have a great New Year's Day 2009!