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Good morning everyone,
The weather pattern continues to go through what I call "chaotic changes". There isn't much organization to the weather pattern and it looks different every few days. We did get some rain on Sunday morning but we are still way behind average rainfall for the month. September is often a wet month and October is often a dry one. So, hopefully we will catch up soon.
There is a good chance we will catch up a little bit as two storm systems are moving our way. Look below at the evolution of the upper level flow. Look at the Pacific Northwest. A strong shortwave trough is digging into the longwave trough position.
Click to enlarge (Thursday morning GFS forecast)
Click to enlarge (Friday morning GFS forecast)
Did you notice how a shortwave can become an upper low? Storm #2 was just a wave of energy diving south from near Seattle. It then forms into an upper low by Friday morning. The evolution of this developing storm will affect the weekend. Based on the trend I think there will be a somewhat significant rain event, but will it be here or all around us AGAIN? Think about that shortwave for a second on Thursday morning's map. This is the 60 hour forecast from last nights GFS model. So, that shortwave is moving across the Pacific, right now, as some energy then it gathers strength as it digs towards a longwave trough position which has been slowly forming over the Rockies. By 84 hours, or Friday morning, the shortwave has formed into an upper low and now is strong enough to affect the surface. How this storm evolves in the upper levels will be crucial to how we are affected this weekend. This is one big reason why forecasting the weather is very difficult. We are forecasting a storm system that is NOT THERE at this moment. It will either be stronger than predicted or much weaker and move by faster. The trend is for it to be stronger. I will certainly be going into detail tonight on the air.
Storm #1 will try to take the limited moisture east of our region and this could be a major factor for storm #2. But, if storm #2 is strong enough it will pull the moisture back into it. Is this exciting for you? It is for me. But, we have been through so many misses and non events that I am still concerned that this will pull something on us again.
Statistic of the day (Days 85 degrees or higher):
August 26th to September 22nd
2005: 22 days 85 degrees or higher
2006: 2 days 85 degrees or higher
So our summer was cut short as it seemed to end on August 26th which is pretty amazing considering how hot it was! In the end we had a short and hot summer that was drier than average, but only a little bit.
Have a great day!
Posted by at September 19, 2006 6:24 AM
I have a 1:30 tee time in Lee's Summit Thursday. Do you think it will still be raining? Thanks.
Right now it doesn't look good. But, it could still change.
Posted by: Derek at September 19, 2006 1:01 PM
The Question I Have about Thursdays storms is in Thermodynamics. Can enough heating rise up enough to produce enough lift to allow enough heating to mix into the mid levels to produce Marginal breif just above severe level storms. The threat if Severe levls are topped would be breif small hail and maybe an 50 to 60 MPH Outflow wind gust. At this Time IM leaning more towards Cold air takeover of mid to low levels Limiting Severe potentail. I just can not totaly rule out a breif just above severe level storm though. Oh well IM just thinking here.
De Soto Kansas
We can't rule out severe weather at all. This must be watched closely as moisture is being pulled northward in limited amounts. There won't be much capping and thunderstorms could be widespread which would limit severe potential, but let's see what it looks like tomorrow.
How much heating will there be? We just don't know yet.
Posted by: Steve Newport at September 19, 2006 1:12 PM
The low temperatures this morning once again proves that Kansas City has a large urban heat island. The low at Downtown was 48F, KCI 47F, Johnson County Executive 46F, but Lawrence was 40F.
The Lawrence temperature is taken at the Municipal Airport, which is located in a rural area two miles north of I-70.
I always wondered where that airport was. It always reads low so it must be in a low lying area.
Posted by: Devin at September 19, 2006 4:59 PM
Since summer is fading fast and fall is comming in with a punch i assume we will not be seeing any more severe weather. If there is still some left what are your thoughts for some on tuesday. Are we talking showers or are we talking about t-storms. Any Strong?
There is some potential for severe weather with the Thursday storm system. And, the second season is just now under way. So, we have to watch these set ups for possible severe thunderstorms.
Posted by: Jeff at September 19, 2006 5:32 PM
Hello Mr. Lezak,
How much rain do you think we will get. Upwards of an inch? Any severe weather?
We are going to do a graphic with an emphasis on rainfall amounts in the forecast tonight at 10 PM. Right now I am thinking close to one inch with a slight chance of a severe thunderstorm. But, we are waiting on the new data.
Posted by: Ben Tracy at September 19, 2006 6:45 PM
Gary...great post. I guess I am the big weather geek that loves that kind of analysis. But it is a teaser too...I want to learn more about the transistion from shortwave to longwave/upper low.
It kills me..I should just go to school for this stuff [so much to still learn!], but I am already entrenched in a career. Too bad the NWS doesn't pay more! LOL.
Oh...and thanks for identifying the odd shortwave that is coming from the SW...that finalizes this short cycle. Now..we are about a week away from the next powerful low...then the cutoff like scenerio, then another wierd shortwave from the SW.
Is it possible to have mini cycles in the GRC? Wait..no..don't answer...I know what you will say. ;-)
First of all there are some mini cycles within the GRC. So, you aren't that far off. My big point to you though is that next week or the week after most likely won't be like this at all as the pattern is going through chaos.
Secondly, going to meteorology school won't teach you all of this. Just picking up on it through this blog can help you a lot. I will add in some other thoughts from time to time. The shortwave energy diving into the developing longwave position is actually a very important part of the GRC. Where will the "long term" longwave troughs and ridges set up this winter. Last year a strong long term longwave ridge was near us which is not good. I am the one who has come up with this term "long term" longwaves.
Posted by: Scott at September 19, 2006 8:00 PM
If only there was something a bit closer than OU/OSU. Sigh. I think the schooling would help me a bit more with some of the basics...though in the last two years between this blog and my favorite tropical blog, I have learned alot regarding the dynamics. Moreover, I have learned ALOT in reading maps and understanding how they work. That aside...I don't have the time to really put in the work to gather maps, trend, and get my own analysis backed up properly...that will keep me a somewhat informed, but otherwise amateur weather hack. LOL.
I think most of the tropical energy is now in motion and should be done in the next two weeks. October and November will be very bleak with the outbreak of the Nino.
As your GRC is dependent on your longwaves, wouldn't the increase of the subtropical jet in Nino years have a tendency to create a persistent high in the SW affecting your longwave patterns? Or would you defer to the other movements in how they would push around persistant H or L centers?
Last thought..not this next powerful low due in about 5 days, but the following one...October 19-23ish? should bring the first snow. Call me crazy..calling my shot. Probably will miss..lets see if my mini pattern is right.
Be patient. The thoughts that the pattern we are in now will continue and affect us around October 19th will not hold up. It will be a new pattern. Watch! You learned a lot during the past year and saw how the pattern went through the cycle. You will learn to trust this amazing October 10th to November 10th period.
And, El Nino may strengthen the southern jet stream, but it will have NO impact on where these "long term" longwave troughs and ridges are located.
Posted by: Scott at September 19, 2006 9:35 PM
I just want to say than northern Lenexa dropped to 42° this morning. Johnson County Executive does not represent everyone, and I do not live in a low lying area at all!
P.S. I really enjoy your conversations with Scott. I am learning a lot.
We will have to save the conversations with Scott and then we can write a book.
Posted by: David at September 19, 2006 11:10 PM
Hello Gary, you love your dedication and hard work but please clarify, that if its going to rain 100% then there is no chance of rain but a guarentee of rain . Making it 100% makes it a certainty thus saying a 100% chance of rain is self contradiction. Keep up the good work.
We have always put a percentage chance in the forecast. And, we decided to just go for 100%. It shows that we are 100% certain it will rain on Thursday. We could have gone 99%, would that have been better. It is sort of a special affect to make it clear. If we leave the percentage chance out then you may wonder, well what is the chance that day?
Posted by: jorge at September 20, 2006 3:46 AM