Absolute Vorticity

tpweather wrote: ↑Wed Dec 01, 2021 7:43 am Good Morning Les and Bgoney. Many of the new folks on here probably have not seen some of the weather discussions on here when folks have different outcomes in longer term forecasts. When this happens the discussions are wonderful as each person sees the outcomes in different ways and over the years when this happens it is usually about a 50/50 split which outcome is correct. First glad I mowed yesterday as the rain is falling at the moment. We knew the warm up is coming and everyone agreed on that part of the forecast. The weekend imo was going to be the change to the overall pattern and though I may be a day or so late I still believe that will happen. Why do I believe that is going to happen when some of the computer models and the tellies they throw out say otherwise. I look at the weather across the world and try to see where the pattern is and factors that will change a pattern. No doubt Alaska has been cold over the past month and that includes the entire state which is not always true with these cold outbreaks up there. Major storm coming in this weekend and this should send mild air across much of the state and temps should rise to normal or even above normal by next week. This in turns sends the current cold air further east across much of western and central Canada. Then we need a way to get that cold into the lower 48. This of course is usually done with a big storm or several storms that push the jet further south. I believe in the several storm outcome starting very early next week. Again if the tellies are correct then my forecast will not be accurate and once I see that the tellies are correct I will change the forecast but at the moment nothing has changed in my thinking. We have plenty of cold air on this side of the globe and just grabbing some of that cold can produce winter weather for us locally. First full week of winter starts next Monday and I use the 4-4-4 rule in winter weather around here. Four weeks where the pattern is terrible and winter weather is unlikely,four weeks where the pattern is great and winter weather is likely and the one we start out with next week where the pattern is good enough to produce winter weather and chances are more of a 50/50 chance. Again each winter is different and sometimes going by weeks is not easy but if you split the winter chances for us locally you get that 1/3 of the season for each item I mentioned before. No doubt I will be watching the weather over the world the next several days and this should either confirm my thoughts or tear them apart.

Bgoney wrote: ↑Wed Dec 01, 2021 8:03 am I don't think we're that far apart Tim. The cold air is there, I just think the lows that could develop won't be strong enough to bring the colder air in for CVG land to give us anything substantial other than flurries/mix. Long ways out and like you , I won't care one bit to change my thoughts if need be.

cloudy72 wrote: ↑Wed Dec 01, 2021 10:21 am That would most definitely set us up for a rockin' January start if that materializes.

tron777 wrote: ↑Wed Dec 01, 2021 10:16 am Would love for this to be right - From Kyle MacRitchie's experimental MJO model:


realtimemjo.png

tpweather wrote: ↑Wed Dec 01, 2021 10:47 am

tron777 wrote: ↑Wed Dec 01, 2021 10:16 am Would love for this to be right - From Kyle MacRitchie's experimental MJO model:


realtimemjo.png

Hey Les how accurate is Kyle's mjo model. I only follow it when you post on here. The current Aussie has us mid-way through phase 5 as of November 29th. Thanks

tron777 wrote: ↑Wed Dec 01, 2021 2:25 pm Hey Tim... the Euro run overall as a whole was colder then the GFS. It shows more of a coast to coast trough versus the GFS which has the trough out west and of course the SE ridge for us. Anyway for wintry weather to occur next week, we're going to need a stronger Canadian high to drop in behind our Sunday rain maker. Then we want the weaker system to follow it up while we have the cold air in place for snow. Those two things must be there or you get the GFS cutter solution for next week.

tpweather wrote: ↑Wed Dec 01, 2021 2:37 pm

tron777 wrote: ↑Wed Dec 01, 2021 2:25 pm Hey Tim... the Euro run overall as a whole was colder then the GFS. It shows more of a coast to coast trough versus the GFS which has the trough out west and of course the SE ridge for us. Anyway for wintry weather to occur next week, we're going to need a stronger Canadian high to drop in behind our Sunday rain maker. Then we want the weaker system to follow it up while we have the cold air in place for snow. Those two things must be there or you get the GFS cutter solution for next week.

Exactly Les and we are on the same page on this part of the forecast. Just saw the NWS out of Fairbanks put out a special weather statement about a major winter storm for the western coast and western interior of Alaska late in the weekend and early next week. This is one of the points I made on how a pattern can change. Will watch the development of the storm but good to see that part of the forecast may come true.

cloudy72 wrote: ↑Wed Dec 01, 2021 2:34 pm Rainfall so far today in my hood at 0.09" with another round coming in from eastern Indiana within the hour. This looks to stay mainly north of the river at this time.

tron777 wrote: ↑Wed Dec 01, 2021 2:42 pm

tpweather wrote: ↑Wed Dec 01, 2021 2:37 pm

tron777 wrote: ↑Wed Dec 01, 2021 2:25 pm Hey Tim... the Euro run overall as a whole was colder then the GFS. It shows more of a coast to coast trough versus the GFS which has the trough out west and of course the SE ridge for us. Anyway for wintry weather to occur next week, we're going to need a stronger Canadian high to drop in behind our Sunday rain maker. Then we want the weaker system to follow it up while we have the cold air in place for snow. Those two things must be there or you get the GFS cutter solution for next week.

Exactly Les and we are on the same page on this part of the forecast. Just saw the NWS out of Fairbanks put out a special weather statement about a major winter storm for the western coast and western interior of Alaska late in the weekend and early next week. This is one of the points I made on how a pattern can change. Will watch the development of the storm but good to see that part of the forecast may come true.

I saw that yesterday Tim from the Fairbanks office. AK has been off and running for wintry cold and weather over the past month. That looks to continue. The one thing though getting back to the models is that I noticed the EPO fold over ridge that helps us to even get a shot for snow next week... on the GFS it's gone just as quick as it came. However the Euro keeps it intact thus making it colder on its run for most of next week. So in short, we need to see changes in the Pacific for us to have shots at wintry weather. The Euro at least on this run has done that. Not ideal but gives us a chance nonetheless.