Thursday, December 31, 2009

12/31 - 5:30pm - New Year's Eve... Here Comes the COLD!

It's New Year's Eve and people are already gathered around Times Square in New York City. It's the end of a decade and time to start a new weather pattern as well. Judging by computer models, I think Mother Nature may have some interesting plans in store for the start of 2010.

COLD. Whether you live in Louisville, Kansas City, Denver, or even Jackson, Mississippi, you're going to hear and say that word a lot over the next few weeks. Arctic air, and I do mean ARCTIC, will finally push into the eastern half of the US this evening and tomorrow. The Arctic Oscillation is very negative right now, meaning high pressure over the Arctic is pushing the cold air south. We're overdue for this cold blast because the AO has been negative for all of this month, but now it's going off the charts negative. Louisville will have highs in the 20's this week and next, with lows plunging into the single digits at times. Mississippi may have trouble pushing 40 for highs next week and lows will certainly dip into the teens.

SNOW. That's a word many in the Ohio, Mississippi, and Tennessee Valleys have been saying for weeks now, but nothing has really come of it. Now that the cold air will finally be in place, snow looks like a fair bet for these areas. The GFS model has been bringing a couple of nice storms through these areas sometime between the 7th and 12th and it's not backing off. Right now the storms are pretty suppressed to the south on the GFS because of the intense cold air in place over the Central US, but if history repeats itself, one or both of these storms may drift northward on the computer models over the next few days. Louisville would certainly be impacted if this happens.

Here's what the NWS in Louisville says about the first storm for Wednesday and Thursday:

THIRD...AND PERHAPS OF MOST CONCERN...IS A STORM SYSTEM WHICH THE LATEST 12Z GFS AND ECMWF(AND TO SOME DEGREE THE GEFS ENSEMBLES) ARE TRYING TO SHOW FOR WEDNESDAY NIGHT AND/OR THURSDAY. BOTH MODELS DIG A SIGNIFICANT SHORTWAVE SEWD OUT OF CANADA AND CARVE OUT A NICE UPPER SYSTEM OVER THE NATIONS MIDSECTION. IN TURN...AN AREA OF SNOW DEVELOPS IN THE MODELS AND HEADS ACROSS OUR AREA. MODELS HINTED AT SOME FORM OF A SYSTEM IN PREVIOUS RUNS AS WELL. AT THIS TIME RANGE HOWEVER...MODELS CAN BE EXPECTED TO CHANGE FROM RUN TO RUN ON THEIR FORECASTED EVOLUTION AND POSITION OF THE SYSTEM. THUS...WILL ONLY MAKE MINOR CHANGES TO CURRENT FCST...THAT BEING TO ADD A CHANCE OF SNOW ON THURSDAY...TO THAT ALREADY IN THE FCST FOR WEDNESDAY NIGHT. MODEL QPF AT THIS TIME IS NOT MUCH...BUT IN A COLD AIR MASS...SNOW-LIQUID RATIOS WOULD BE QUITE HIGH. SOMETHING TO KEEP AN EYE ON...BUT CERTAINLY SUBJECT TO MUCH CHANGE BETWEEN NOW AND THEN.

Mississippi may see some snow action from this system, and the NWS in Jackson is right on top of this:

THINGS LOOK TO CHANGE ON WEDNESDAY HOWEVER AS BOTH THE GFS/ECMWF SHOW A POTENT UPPER TROUGH DIGGING INTO THE PLAINS WHICH SHIFTS THE SURFACE HIGH THAT WILL BE IN PLACE TO THE EAST...ALLOWING WEAK WARM/MOIST RETURN FLOW TO DEVELOP. STILL PRETTY FAR OUT TO BE CERTAIN ON ANY DETAILS BUT MODELS ARE HINTING AT THIS TROUGH DEVELOPING A WEST GULF LOW ON WEDNESDAY THAT WILL BRING A RETURN OF PRECIP CHANCES TO THE ARKLAMISS WEDNESDAY MORNING INTO THURSDAY. LOOKING AT FORECAST SOUNDINGS...THIS SYSTEM WILL BE CAPABLE OF BRINGING A RAIN/SNOW MIX TO AREAS NORTH OF I-20 WITH PRIMARILY RAIN SOUTH OF I-20 ALTHOUGH THE 06Z GFS BUFR SOUNDINGS SHOW A PRETTY GOOD INDICATION OF SNOW AS FAR SOUTH AS HBG. ADDITIONALLY...IT APPEARS LOOKING AT THE TEMP PROFILES THAT 850-700MB TEMPS WILL REMAIN BELOW FREEZING ALTHOUGH IF STRONGER WARM AIR ADVECTION OCCURS AND THESE LEVELS NUDGE ABOVE FREEZING WE COULD SEE SOME ICE EARLY WEDNESDAY BEFORE STRONGER COLD AIR ADVECTION TRANSITIONS EVERYTHING TO SNOW IN THE AFTERNOON. CONFIDENCE IS NOT HIGH ENOUGH TO WARRANT ANY OUTLOOKS THIS FAR OUT...BUT THE POSSIBILITY OF A SIGNIFICANT WINTER STORM...EITHER COMPOSED OF ICE AND SNOW...OR JUST SIGNIFICANT SNOW ACCUMULATIONS MAY VERY WELL BE ON THE HORIZON FOR THIS TIME PERIOD.

We'll see how this and the second system between the 9th and 12th develops. Maybe it's finally our turn in KY, IN, TN, TN, MS, and AL to get some snow!

Wednesday, December 30, 2009

12/30 - 10am - I'm in the Courier-Journal Today!

Louisville's Courier-Journal published an article about my meteorological pursuits in the Neighborhoods section of the paper. It was very well written and the layout in the print version is very nice. Here's a link to the online version of the article: Click here

(Note: There is a typo in the title of the online version)

Tuesday, December 29, 2009

12/29 - 7pm - Snow Update, Newspaper Article Tomorrow

The warm air looks to be winning out on the computer models for the system coming through tomorrow and Thursday. Rain should start tomorrow evening and transition to snow showers by Thursday evening. I think we're in for a half inch on the ground by the time Friday morning rolls around, but we could see up to an inch if temperatures drop faster than expected. The precipitation graph on the left was generated from the 18z GFS using BUFKIT, and it shows well how the rain (green bars) switches over to snow (gray bars) on Thursday evening. We may have some road problems on New Year's Eve as the wet roads freeze, so be careful out there!

If you live in Southeast Louisville, particularly the suburbs of Jeffersontown, Middletown, Fern Creek, and Hikes Point, open up the Neighborhoods section of the Courier-Journal tomorrow. They're running a follow-up article on the one they published about my website back in January. This follow-up article may also run in an abbreviated format in other Neighborhoods sections around East Louisville, so be sure to check your paper even if you don't live in the suburbs I mentioned. I'll be sure to post a link to the online version once it becomes available on my website, blog, and Twitter/Facebook. Thanks again to the Courier-Journal for writing these articles!

Monday, December 28, 2009

12/28 - 2pm - A Difficult Snow Forecast

Hope that everyone in Louisville enjoyed the dusting of snow that came last night. Here's a little 6-inch snowman I was able to put together as the snow was falling:


The New Year's snow chance is still on the maps. The computer models are having difficulties trying to hammer down a track for this storm, but I think we may have a shot at 1-4" of snow. The precipitation amounts are different on all of the models right now, so that's about the best estimate I can offer at this point.

The 12z NAM run is a little warm for us in Louisville, but the track of the low is sufficient to generate a good snow around here if temperatures cooperate. There's a coastal low that may form as well, and that could impact how much precipitation we receive and the storm track.

The 12z GFS run is similar to the NAM, but the low is further east by a few miles. This helps to lower our temperatures a little bit, so we wouldn't have as much rain before the precipitation changes to snow. That coastal low shows up on the GFS as well.

The 12z ECMWF (Euro) is difficult to read because of the large time difference between frames this many days out, but you can see that it favors the low pushing further east and pushing off the coast.

Here's what the NWS in Louisville says about this system:

SO...WHAT KIND OF PRECIPITATION WILL IT BE? THAT IS A DIFFICULT QUESTION TO ANSWER AT THIS TIME. TAKING OUR BEST SHOT...FOR WEDNESDAY THROUGH THURSDAY IT LOOKS LIKE THE NORTHERN SECTIONS OF THE AREA /SOUTHERN INDIANA AND NORTHERN KENTUCKY/ COULD SEE PRIMARILY SNOW WITH SOME RAIN MIXING IN DURING THE WARMEST AFTERNOON HOURS. CENTRAL PORTIONS LOOK TO BE A RAIN/SNOW MIX...AND SOUTHERN KENTUCKY SHOULD SEE MOSTLY RAIN WITH SOME SNOW MIXED IN WEDNESDAY NIGHT.

....

CANNOT SAY WITH CONFIDENCE YET JUST HOW MUCH SNOW WILL FALL...BUT IT DOES LOOK LIKE ACCUMULATING SNOWS WILL BE POSSIBLE LATER THIS WEEK JUST ABOUT EVERYWHERE. STAY TUNED.

From what I've seen, I think we may start with a period of light rain on Wednesday evening as the low approaches the area. Cooler temperatures should filter in and change everything to snow by late Thursday as the low moves to our east. How much snow falls on Thursday and Friday will be determined by the track of the low as it moves northward. If this storm rides up the west of the Appalachians, expect more snow than if the storm moves out to sea or if the coastal low overpowers it. I still say this will be a widespread light snow event, but there's still quite a bit of wiggle room for precipitation amounts and storm track at this point.

Saturday, December 26, 2009

12/26 - 2:15pm - Still Watching for New Year's Snow

I hope that everyone had a wonderful Christmas yesterday and that the lack of snow around here didn't get anyone down in the dumps.

As we shift our focus to the new year, we may also have to shift our focus to a chance of snow in Louisville. Over the past week, the long-range GFS computer model has been showing a storm tracking through the Gulf states. While the moisture and precipitation with this storm has been suppressed to the south on most model runs, I'm starting to see the (this) season-typical northward trend in the track of this storm.

The Euro model has this storm tracking from the Gulf Coast to Virginia, which would be a fairly decent track for us to have snow in Kentuckiana if enough moisture accompanies the storm. My worry is that there may not be enough cold air in place to counter the warm air being brought north by the storm, and this may negatively affect our snow chances. It's still too early to tell if this will indeed be a problem, but at least the storm track is good at this point.

Basically, the graphic from the last post with the potential storm tracks of this system still applies. There are a lot of factors like phasing, the polar vortex, and model-to-model differences that need time to get hammered out. I'd say this is our best chance for snow so far this season, and I think this is certainly a system that bears watching.

Wednesday, December 23, 2009

12/23 - 3pm - Plains Blizzard, Snow in Louisville?

The big storm getting ready to spread rain around Louisville on Christmas Eve will slam into the Plains as a major snowstorm with blizzard conditions possible. Ice will be a big issue out there as well, especially in places nearer to the area of low pressure like Omaha and Lincoln, Nebraska. Some places could end up with more than 20" of snow, especially in areas north of Nebraska. Winter Storm warnings and watches have been issued as the storm cranks up today.

Rain should begin in Louisville early tomorrow and taper off as we go through Christmas Day. I know it's a bummer to have rain around Christmas like this, but at least we won't have any travel problems around the region.

The next chance of snow could come just before the new year. A system on the long-range GFS computer model is still showing some potential for us, even though we are not forecast to get any snow as of now. The storm track at the moment is very far south of us, but the GFS model has been notorious for shifting suppressed storms northward a few days before the actual event. This happened with the current storm. As you may remember, the current Plains storm was supposed to track south of us and give us snow, but the northward trend took over and sent the storm west of the Mississippi River. My only concern with the potential New Year's storm is that we may have a surge of warm air from the south, which could limit our snow chances. It's really far out to be making any sort of detailed prediction at this point, but I think this storm will make a snowy impact on parts of the region.

Monday, December 21, 2009

12/21 - 12:45pm - Christmas Rain, New Year's Snow?

Unless there are any major changes in the computer models in the next 24 hours, I think we're in for some potentially heavy rain on Christmas Eve in Louisville. The rain should taper off on Christmas Day, ending as a few snow showers or flurries if we get lucky. There could even be some thunder on Christmas Eve if convection gets going around here. This same storm will give places like Omaha and Lincoln, Nebraska a nasty winter storm with dangerous amounts of ice and snow. I know everyone in Louisville wanted a white Christmas, but quite honestly it's better to have the rain then have another ice storm on our hands during the holidays.

The reason we're missing the snow is because of a lack of high pressure support in Canada. Earlier computer models were forecasting a strong high pressure "block" that would drive this storm southward, but later models have since weakened the effect of this.

On to the next storm... The long range GFS has been consistently displaying some sort of potential New Year's snowstorm for the region. There may even be two storms around this period to watch based on the current runs, so we'll have to watch what happens. It's extremely early to be calling for snow or rain for this time period, but I do believe that the pattern will be better suited for snow here next week. So we have the storms, but now we just need some high pressure in Canada/North US to keep them south of us. Today is only the first day of winter, so don't give up on snow yet!

Saturday, December 19, 2009

12/19 - 12:15pm - Update on Snow Chances

Snow did not fall in the Louisville area this morning as forecast because of warmer than expected temperatures both near the surface and just a couple thousand feet aloft. The short-range RUC model runs have been indicating a slow cool down of temperatures over the next few hours, so rain should change to snow later this afternoon. We may pick up a half inch on the grass tonight with any lingering snow showers.

The Christmas Eve snowstorm is having a very difficult time on the computer models right now. The most current 12z GFS run has mostly rain for us because the low cuts up to Chicago, but the previous few runs had been indicating a track just south of Louisville that would give us rain to snow or all snow. With solutions varying wildly from run to run, I don't think we'll have a track narrowed down until the start of next week. I will say that the pattern favors the southern track with snow for us because of high pressure in Canada suppressing any northward movement of the storm. The storm should be following this rule on the models, but unfortunately this is not happening with many of them. At least we still have a chance for snow! Here are some potential storm tracks that the models have been hinting at for the past couple days:

Thursday, December 17, 2009

12/17 - 2:30pm - Weather Talk, Snow on Traffic Lights

I talked to a group of kindergarten and pre-k students today at Tully Elementary School in Louisville about weather today. I covered storm chasing, weather safety, snow, ice, and even demonstrated how a NOAA weather radio works. Best of all, each kid walked out of there with a severe weather safety coloring book and brochure, courtesy of the National Weather Service office in Louisville. Here are some pictures:




It was a lot of fun and I hope they enjoyed watching some of the video I brought in, as well as the talk itself.

Since it looks like we may get a couple inches of snow this weekend, I wanted to pass along an article I found about snow covering LED traffic lights, which Louisville has quite a number of. You can discern if a traffic light is LED or not by looking for a pattern of small dots on each light.


MILWAUKEE – Cities around the country that have installed energy-efficient traffic lights are discovering a hazardous downside: The bulbs don't burn hot enough to melt snow and can become crusted over in a storm — a problem blamed for dozens of accidents and at least one death.

12/17 - 12pm - Louisville Snow Chances Increasing!

This weekend's snow has really cranked up on the computer models over the past 24 hours. Moisture on both the NAM and GFS has increased considerably, meaning we could be left with over two inches of snow by Sunday night. The combination of the coastal winter storm giving us some outlying snow and the round of clipper systems from Canada should be beneficial for snow totals, but I'm just a little worried about surface temperatures. I think we'll top out at 33 or 34 on Saturday, which should be when the bulk of the snow is falling. This will melt things a little bit, but I think things will cool down quickly at night and snow will still be falling. A little burst of snow on Sunday should top off our accumulations of 2 or more inches.

The Christmas Eve storm is still up in the air at this point, but I think our chances are getting better for an accumulating snow. The 6z run of the GFS had the storm going to our south (that's good for snow here) and put down over 5 inches of snow. The 12z has a strange solution with mostly snow here, but the low pressure associated with the storm takes an odd path northward to Tennessee then cuts east. We'll see how this track goes, but I think the fact that the storm is still on the computer models and that there is a potential track that favors snow for us is a good thing.

Tuesday, December 15, 2009

12/15 - 11:30am - Clipper Snow, Christmas?

A clipper system (low pressure that dives south from Canada) is forecast to come through the region this weekend, spreading light snow around Louisville. It looks like there will be some accumulations, just enough to whiten the ground by the latest estimates. I'm not terribly sure of the exact amount of snow we'll receive because this system has been bouncing around on the computer models. The main idea is that snow showers will start on Friday night and continue through Saturday.

You may have seen my various hints on Twitter and Facebook about some sort of snowstorm developing next week just in time for Christmas. The GFS long-range model had been advertising a potentially potent storm on December 24th for us, but that has since disappeared in the last few runs of the model (which could be due to the fact that the GFS model had some technical upgrades implemented today). Fear not! That storm has been replaced by several rounds of light snow between the 22nd and the 25th, meaning we still have a chance for a white Christmas if this happens. We're still 10 days away, so the forecast models will be very erratic and our big storm may even come back. On the flip side, there's a good chance that the snow could disappear completely and we'd be left with a cold, dry Christmas. Either way it'll most likely be cold enough to snow. Don't get too excited yet because this is a tricky forecast, but keep in mind that we could be dealing with some snow on or around Christmas.

Saturday, December 12, 2009

12/12 - 11:45pm - Looking for Snow

I know many of us here in Kentuckiana are waiting for the first big snow of the season. While we generally don't see much snow around Louisville in December, the pattern right now in my opinion is very ripe for an early season snowfall. The long range computer models (GFS & Euro) heat things up this weekend and early next week, but temperatures quickly turn downhill again by the middle of next week. We may even see a small bit of snow next weekend with a possible clipper system. The southern storm track, the one that brings most of our snowfall, has been and will continue to be very active throughout the arrival of this new batch of arctic air next week. Receiving snow in Louisville is all about timing, which means we have to have an abundance of cold air in place as a low pressure system tracks to our south and east, preferably along the mountains of Eastern Kentucky. Having one of these components out of place would mean rain or ice for us here in Louisville.

Many have asked: Does it look like we'll have a white Christmas? The answer is maybe. The possibility for light snow between now and the 25th looks pretty good right now, but getting a big storm in here will be tough. The GFS computer model has been hinting at some sort of snow event around Christmas for a couple days now, but accuracy that far out is very low. I'd say our chances for a white Christmas are probably the best since 2004, when we had a crippling snow/sleet system dump over a foot of snow in Louisville and Southern Indiana on the 22nd and 23rd of December. Just keep in mind that the pattern is ripe for snow, but that the specifics are blurry at this point.

If you're desperate to see some snow, head across the Ohio River to Paoli Peaks in Southern Indiana. They've been able to generate enough machine-made snow to open for skiing this weekend and they should be able to keep that snow on the ground through the warm spell we'll see early next week. Guess it's time to hit the slopes!

Wednesday, December 9, 2009

12/9 - 12:30pm - Back to Louisville!

It's been a great Fall semester here at Mississippi State University, but final exams are over and it's time to head back to Louisville for the long winter break. I was pretty stoked about going back up north until I saw the forecast for Louisville tomorrow: Sunny with a high of 26, windchill values as low as 7. That's cold! Nevertheless, it'll be a nice drive home today and I can't wait to be back in the Derby City.

Over the next few weeks I'll be writing about Louisville weather, weather news, and weather-related stuff on the blog when I have time. If a snowstorm decides to visit Louisville while I'm up there, you can expect full coverage on this blog as well.

Tuesday, December 8, 2009

12/8 - 11am - Severe Weather in Mississippi

It may be December, but we're talking severe weather today around Starkville. A low pressure system that's giving blizzard-like conditions to areas of Nebraska and Iowa will help spur the development of severe storms around the South. Moist air drawing up from the Gulf of Mexico in the warm sector of this system coupled with high amounts of shear and very fast upper level winds should lead to some supercell thunderstorms this afternoon. There is a tornado and wind threat from this system, and any storm that forms will move very quickly. Instability won't be the best today, but nevertheless I think there is enough for severe weather to get rolling this afternoon. Here's the latest outlook from the SPC:


We're in a SLIGHT Risk today, with a 10% tornado risk from Starkville down to Hattiesburg:


I'm finished with my final exams here at MSU, so I'll be able to track this situation all day today. Keep watch on my Twitter and Facebook updates for further information. If things get extremely active this afternoon, I'll start putting updates on the blog as well. Everyone in Mississippi needs to stay alert today!

I'll be on my way home to Louisville tomorrow for Winter break, so the Mississippi weather updates will be on hiatus until early January.

Sunday, December 6, 2009

12/6 - 5pm - Video from the Starkville Christmas Parade

Here are some video highlights from the Starkville Christmas Parade last night. I reported live for channel 5 WOBV during the 1 hour 30 minute long broadcast. There are some funny moments mixed in! It was a great parade and I'm happy to have covered it with channel 5.



I'll have the full parade posted later if you would like to see the whole broadcast.

Wednesday, December 2, 2009

12/2 - 2pm - Reporting from the Starkville Christmas Parade

Here's the big announcement you've been waiting for!

I'm going to be an on-the-street reporter for the Starkville Christmas Parade this weekend. My responsibilities will include interviewing parade spectators and participants live on camera, as well as doing some promotional and weather spots. The parade will be broadcast live on cable channel 5 WOBV here in Starkville starting at 5pm on Saturday. The broadcast will be shown repeatedly throughout the month of December as well. I'll be sure to record it and post it here on the blog for everyone to see.

You may be wondering how I came to get in this position. Through some wonderful connections I have at Mississippi State's IT department, I was asked to fill-in for the person who normally has this position. With this being my first long-form broadcasting gig, I'm really excited and I cannot wait to get out there and meet everyone!

Again, if you're in Starkville, this will air at 5pm Saturday on channel 5 WOBV. See you then!