LRC Forecast Experience
The Gary Lezak Weather Blog
Good morning Weather2020 bloggers,
The storm system moving out into the plains has already produced out west. California has been receiving a little break here and a little break there as the drought is likely going to continue to gradually weaken it’s grip in the coming weeks and months. The most recent storm, the fourth one to hit the Sierra Nevada mountains already this season, just dumped snow on the California ski resorts. Take a look at this picture sent in from Jeff Boris in the Tahoe Keys area of Lake Tahoe on the south shore:
This is at just above 6,200 feet up. Look at the docks and how low the water is. Boats have been barely able to get out of the Tahoe Keys and onto the lake this summer, and apparently the lake was even lower as of this week. This is likely going to change by next spring and summer if the snow pack continues to grow. The LRC is pointing in that direction, but it’s still very early in the season. The rainy season kicks into high gear in January and February out west. And, this part of the pattern will be cycling back through this winter. I still have some concerns that California is not in the direct path of the wrath of this year’s EL Niño. We are still doing some more analysis of this pattern and we will discuss the rainfall potential out west in our in-depth winter discussion next week. Los Angeles has still been fairly dry this season, and it has my attention. Only 0.01″ of rain has fallen in Los Angeles this month, and the month is almost over.
What is this storm going to do as it moves east? Well, it really is going to get stuck over the west, and while it does Kansas City is about to have it’s wettest Thanksgiving Day ever recorded. Kansas City has never had an inch of rain on a Thanksgiving Day and our forecast is for 1 to 2 inches of rain to fall with a few spots possibly getting more than that. Kansas City averages 2.15″ for the entire month, and this is the second wet storm in the past couple of weeks.
Here is the latest LRC Index. You can click on this graphic for a much larger view. The cycle length continues to evolve and we will be able to firm up what that cycle length is within two to three weeks, as we do every year in December. The new LRC evolved from August into October, and this pattern truly began around that first week of October. We must wait for a match and this will happen as we move into LRC Cycle 2:
Big Changes In The Pattern
The LRC is now set for the season. We are still identifying a few more features, and our in-depth winter forecast will come out next week. Let’s look at this current storm system and how it is evolving. The models are having a particularly difficult stretch of trying to model this developing pattern.
This morning’s new data:
Look at this morning’s surface map:
This is what we call a moisture tongue! We will be discussing this in the spring quite often, as it is looking like it will be quite an active severe weather season in the plains in 2016. Moisture was surging northward from the Gulf of Mexico this morning. Now, look where the front is forecast to be on the latest NAM model valid at 3 PM Thanksgiving Day:
And, look at the temperature forecast:
Who thinks this will be an easy forecast for the Plaza Lighting? This model has it in the 60s just three hours before the huge outdoor event, that will be broadcast live on 41 Action News, and it will be streamed around the world on KSHB.com. I am the emcee and meteorologist for the event. Look at this? Wow! And, that frontal zone is right over KC at 6 PM on this model. Three hours faster and it will be in the 30s for the Plaza Lighting, one hour slower and we have the warmest Thanksgiving Evening on record. Isn’t weather fun?
Happy Thanksgiving Eve! Have a safe holiday weekend. Let us know if you have any questions or comments.
Good morning Weather2020 bloggers,
Welcome to the LRC Forecast Experience Blog. Next week I will be writing up the extensive and in-depth winter forecast as we identify more of the features that are now cycling through this brand new and unique weather pattern. Today, we are going to talk about the still growing monster El Niño, A Thanksgiving Weekend Storm System, and a developing hurricane. Yes, a late November hurricane is likely going to form in the next few days over the eastern Pacific Ocean and it may have impacts in the United States as the moisture gets drawn into this developing storm system.
Let’s begin with the latest El Niño status:
The latest temperature anomalies have come in, and this powerful, and possibly strongest El Niño ever recorded, continues to strengthen. The latest anomaly just reached it’s warmest temperature at 3.1°C above average. We are now in a full fledged powerful El Niño event. The Tropical Pacific Ocean waters are quite warm off the South American coast and there will be major impacts this winter.
Possible Hurricane Development:
The eastern Pacific Hurricane Season is supposed to end on November 3oth. This storm may become the 18th named storm this season, and if it is named, it will be called Sandra.
A tropical system is now developing well off the Mexico coast. You can see the developing system on this enhanced satellite picture from around 7 AM this morning.
A Thanksgiving Weekend Storm System:
A strong storm is now developing near the northern California coast. There is a heavy precipitation event in progress from northern California north into Washington and Oregon with snow at the higher elevations. This is another system coming in from the northwest, so it is not impacting Southern California with the highly anticipated rains from any El Niño influence so far. These rains may come later in the winter, but for now these systems are just missing them to the north.
This first map on the left can be clicked on for a larger view. It shows the flow aloft today. There is a wave of energy being kicked out of the western states and out over the plains, but it is a dry system. This would likely be a wet system in May or June when more low level moisture is available. It will produce a band of clouds and maybe a sprinkle or two today. The main and rather strong storm is intensifying over California today. The main jet stream is still over Canada, and this flow is indicative of an AO and NAO positive index.
Look at what happens by the day after Thanksgiving. The upper low gets stuck, and completely cut-off from the polar jet stream over Canada. The flow becomes even more split off the west coast, and this system will be producing some excessive rainfall. The models will have a very difficult time in the next few model runs while this unusual process develops. What I mean, is while this high over low tries to form the flow aloft will likely have many different solutions, and how it will impact the weather in each location is going to be challenging. Take a look at this precipitation forecast between now and Friday night:
As you can see there is a forecast of over five inches of rain over parts of north Texas, Oklahoma, and into northern Arkansas. This is the area we picked out in our preliminary winter forecast to be very wet this winter, and it is already starting. After Friday, the pattern becomes even more complex. Take a look:
By the end of the weekend, the upper low will begin to get forced out. For Kansas City to have any winter precipitation this upper low, that you see in Idaho, would have to be much farther south. Or, at least that lead strong disturbance would have to track across Texas and not southwestern Kansas. This is another symptom of the high AO and NAO indexes.
What does all of this mean? We will sort it out in the next few days. For Kansas City it likely means that all of the precipitation will be in the liquid form despite a strong cold front moving through and a storm coming out into the colder air. In other patterns this would be a recipe for snow and ice, and there will likely be that transition zone, but farther north and west. We will discuss this as we get closer to the holiday weekend.
Thank you for sharing in this exciting weather experience. Let us know if you have any questions or comments.
Good morning Weather2020 bloggers,
We are now moving through the big Thanksgiving week with a big storm developing. All weather forecasts are complex because we are predicting the future. But, some are even more complex than others, and this week has many of those challenges. Let’s take a look:
Energy is now coming into the Pacific northwest coast as a trough, i the shape of a tilted V. We have seen energy come into the flow in this configuration as this pattern began setting up in September and October. The flow is unblocked and the AO and NAO indexes are well above zero. A strong cold front is developing anyway and it is about to surge southeast into the plains states. What happens with this energy in the flow is rather fascinating during the next few days.
The upper low forms and closes off by tomorrow evening, as you can see on the right. The flow is still unblocked over Canada. There is a northern branch wave developing, and this wave will likely push the cold front through Kansas City earlier than previously forecast by the models, but it is still just Monday, so let’s keep monitoring it.
The evolution of this pattern in the next seven days may end up bringing Kansas City it’s first chance of snow.
This next map, on the left, shows one forecast solution for Thanksgiving night. A high over low is trying to form near the west coast. The models historically have a very difficult time forecasting these blocks and then they have a very hard time forecasting what will happen next. This pattern is actually quite similar to how it set up in early October, but with so much more energy now into the flow we are about to experience something rather fascinating this week. Now, how will it impact us, and what comes out of this pattern early next week?
Look at what happens by Saturday night. The upper low reforms/evolves and is forecast to be spinning over the west. The high over low blocking only is forecast to last a very brief time with the main flow continuing at very north latitudes over Canada. Forecasting what will happen next is going to be quite difficult. The surface will be in “chaos” after the front pushes south, and how it sets up later this weekend will decide who has a chance of winter precipitation. We will look at the surface map for Thursday evening, and for next Monday, but first look at one solution for how the upper low comes out early next week.
Look closely at this fifth map that I am posting this morning. There is a well defined northern branch over Canada. This flow is a symptom of the AO and NAO staying positive. There is also a southern branch, stronger than normal, and likely a somewhat direct influence from the strong El Niño. The upper level low circulation is forecast to track north of KC, and this would usually indicate that any chance of snow will track to the north. Where will the system really track, and due to the surface being all “messed” up there are all kinds of potential solutions for us to analyze. Okay, here are the two surface maps:
The trend on the models has been for a bit more northern branch dipping into the Great Lakes by Thursday. This would likely help push the cold front farther south. It’s still just Monday, so let’s see how this trends in the next few days, but this solution would be cold and wet for the traditional Plaza Lighting Ceremony Thanksgiving Night.
This second surface map shows one of many solutions for early next week. The blue dotted line, the first one that extends from northern Oklahoma to northeastern Missouri would be the likely rain/snow changeover line. Let’s hang on and try not to analyze this too much. There is a lot that will be going on between now and the end of the holiday weekend.
Have a great start to this holiday week. Thank you for participating in the LRC Forecast Experience blog!
Good morning Weather2020 bloggers,
We have made it to Thanksgiving week and on this Sunday morning, just four days away from the big holiday, we have a very complex weather pattern developing. The models will continue to have a hard time with what happens between now and next weekend. There is a good chance of some brief blocking developing near the west coast with the formation of a high over low block. How this develops will help determine what kind of weather you experience on Thanksgiving Day and the holiday weekend. There will likely be some impacts on travel, one of the biggest weekends for getting to and from your relatives and friends locations. Let’s take a look.
This first map shows the flow aloft over North America, which is valid Monday night. You can click on the map for a larger view. The flow aloft is unblocked with a broad trough over New England and a digging trough off the Pacific Northwest coast. This energy is going to dive south and form into a rather strong upper low. As this happens, it will provide great conditions for snow at many ski resorts out west. This is something that we have not been able to say in years, especially for California. This is still not a storm coming in with a lot of moisture as it is coming in from the northwest and not the west or southwest, which may happen later this winter.
This second map shows the 500 mb flow (18,000 feet up) valid Wednesday night at 6 PM. The flow aloft is still unblocked. Look closely at the eastern Pacific Ocean. A big ridge is developing and if this closes off into an upper high, then we will finally get the flow to block up a bit. As the flow does begin blocking, what happens next is way too complex for the models to handle and figure out. The upper low is going to be ejected out into the plains and in this process it is likely going to fall apart.
This third map shows the evolution of the high over low block near the west coast. The big upper low is forecast to get kicked out and absorbed into the flow. And, a new upper low is forecast to begin developing over California. This upper low and evolution will also be influenced by the system way off the west coast as it gets caught in the southern branch heading towards California as well. This is really a complex development.
There is a well defined northern branch and the developing southern branch.
This fourth map, above, shows the developing high over low blocking well. The models, by this point have many different solutions. The way this pattern develops in the next week is rather obviously complex. There is a lot to monitor here. There is also a tropical system sneaking into the equations south of Cabo san Lucas.
Now what does all of this mean to you? For Thanksgiving Day a strong cold front will have developed and it will only be inching its way eastward. That will be a very cold air mass with some Arctic Air Mass characteristics. Temperatures will likely be below zero near the center of that air mass up north.
Look at where the front is lining up at 6 PM Thanksgiving Night:
Now, imagine you are me, or you are one of the 100,000 people thinking of going to see and experience the tradition of the Plaza Lighting that takes place every Thanksgiving Night at just before 7 PM? This is a forecast map valid at 6 PM Thursday. If this solution is exactly right, then the forecast would be for a 100% chance of rain around that 6-7 PM time frame. And, that front is strong. If it is six hours slower, then it will likely by in the lower 60s for the Plaza Lighting. If it’s six hours faster, then it would be in the 30s. Maybe now you can see why Kansas City was the #1 most unpredictable city in America for big cities in the United States. We have a big challenge ahead.
What would slow it down? That upper low needs to sit back over the southeast and hold together just 12 more hours. Let’s see how today’s models handle this interesting development.
Have a great Sunday. Thank you for reading and participating in this LRC Forecast Experience Blog. Have you entered the forecast contest yet? We are forecasting for the the week of Christmas.
Good morning Weather2020 bloggers,
I saw some very wet snowflakes, or what I like to call slush droplets. They were definitely very melted snowflakes that came down in a heavier downpour around 1 AM. As it moved east, it finally changed to all snow for a brief while just one county east of where I live. From slush droplets to flight delays. Chicago had many flight delays today from the storm that is moving off to the east. Here is the 10:43 AM radar image snowing the snowstorm in progress this morning:
LRC Update: Here is a comment that came in that was posted just as I started a new blog. I will respond here in today’s blog:
From blogger Wes:
First off, let me say that I have been following the LRC for years now, and I am a firm believer in it. I enjoy watching the cycle unfold and repeat through the following year. I have a question about this year’s cycle. I have been watching it, and I was wondering if the big Thanksgiving Week system is related to the one that struck in late October, after the 21st. The main part of the system lifted into the Great Plains, but a southern piece of energy remained and combined with Pacific moisture. This resulted in an overrunning event in Texas with lots of heavy rain near/N of the frontal boundary. The late fall/winter part of this cycle would suggest a potential for Winter Weather in Texas – as the GFS and, to a slightly lesser extent, the Canadian model show late next week. I also noticed that the cool snap that preceded the late October system is similar to this one right now, in terms of the position and strength of the high pressure. Is this just a coincidence or part of the pattern/cycle?
My response: First of all, thank you for asking these great questions Wes. One of the main aspects of the LRC is that the pattern that sets up will have main features that become the dominant features in the overall pattern. Storm systems may look similar in other parts of the pattern, and not just the ones that line up well from cycle to cycle. There are these long-term long wave troughs and ridges where storm systems will intensify as they move into the troughs and weaken as they move out. The later October 21st system is related to what is going on in the next week in that way, but it may not be right on cycle. That storm will also repeat. I am unclear of the cycle length at the moment, and when we clearly identify it, then we can see where all of this fits. So, it isn’t a coincidence. It is all part of this unique weather pattern.
Thanksgiving Week Developments:
Take a look at this dew point forecast from this morning’s GFS model. 55° to 65° dew points are forecast to surge into the plains states from the Gulf of Mexico by Wednesday into Thanksgiving morning. And, notice the higher dew points over the central Pacific Ocean too. I just found that interesting. The dew points are almost always low with the cool Pacific Ocean water near the coast. This is why Southern California is very different from Florida. The coastal areas of Southern California are under the influence of the Alaskan current where the water flows from the Gulf of Alaska down the west coast. In Florida and along the east coast the water flows in from the tropics with the Gulf stream and this high humidity fuels the summer thunderstorms that happen there, and of course it fuels any tropical system that may develop.
The higher low level moisture surging in will be the low level fuel for another heavy precipitation event. Take a look at the surface valid Wednesday evening:
There are two strong surface highs, one over the northwest Atlantic, and the other one, a somewhat Arctic high near the USA/Canada border. The conditions are becoming favorable for this very cold air mass to develop.
The new data has trended in the GFS direction on the timing and strength of the upper low next week. We will discuss this more specifically on Sunday.
Thank you for participating in the LRC Forecast Experience Blog and sharing in this exciting weather experience. Have a great weekend. Let’s see how this next week sets up.
Good late evening Weather2020 bloggers,
Look at this map I just posted on the KSHB blog. It is fascinating really, and there is a major snowstorm in progress north of Kansas City, one state away. Chicago will have it’s first snowfall accumulation of the season tonight as it has just started snowing there. Areas 100 miles south of Chicago are the target for this winter storm, however.
I was trying to explain this the other day, and it is now actually happening. I love it when the weather works like I expected it to, and there is still a lot to monitor in the next few hours. If you remember I talked how the vorticity was going to become oriented in such a way where the band of rain and snow would begin to generate and widen as it approached and passed Kansas City tonight. Take a look at what has just rapidly increased between 8:25 and 9:25 PM. I will be tweating about it as it approaches. There is actually a chance we will see our first snowflakes, even a dusting is possible, even though the chance is somewhat low. I would not be surprised.
Have a great evening. Let’s see if KC has it’s first snowflake of the season early in the morning, around 2 AM. There was a small band west of the city as I was writing this. I will get the blog updated in the morning.