Absolute Vorticity

Rocktober is one of my favorite months of the year! The leaves change and sometimes we can have some wild weather too! Signs of Fall and sometimes snow can even occur. We will start off Rocktober this year with a great looking Friday but rain comes in late Sat afternoon thru the day on Sunday and even lingering into next week with a daily chance for rain thanks to that cut off low. Rainfall amounts for a lot of folks thru Monday looks to be around an inch or so. Discuss!

My favorite month too!! Hoping for some weeks of Fall weather!!

MJSun wrote: ↑Thu Sep 30, 2021 7:15 am My favorite month too!! Hoping for some weeks of Fall weather!!

Hey MJ! Nice to see you. It will def look and feel like fall with cloudy, damp conditions esp Sunday and for a good chunk of next week. Temps will fall from the 80s to the 70s and maybe even stay in the U60s early next week. (Cloud and rain dependent of course).

Looking at the next few weeks and don't see much in the way of cold weather at all but you can get a damp cool day with an upper low. The cold is still over Alaska and will drop down to the northwestern part of the USA. Canada is where we tend to get cold weather and they are for the most part well above normal especially in the northern part of the country. I have no problem with this and sure they will get cold during October and hopefully that will bring some decent snows up there before the jet shifts to far south for the winter. Love the deeper snows up there as this can help in getting the cold to become even colder and when it moves southward it can stay cold longer.

tpweather wrote: ↑Thu Sep 30, 2021 10:19 am Looking at the next few weeks and don't see much in the way of cold weather at all but you can get a damp cool day with an upper low. The cold is still over Alaska and will drop down to the northwestern part of the USA. Canada is where we tend to get cold weather and they are for the most part well above normal especially in the northern part of the country. I have no problem with this and sure they will get cold during October and hopefully that will bring some decent snows up there before the jet shifts to far south for the winter. Love the deeper snows up there as this can help in getting the cold to become even colder and when it moves southward it can stay cold longer.

Like I said in the Sept thread, thru mid October at the very least, I don't see much change to the overall pattern. Troughing where you said Tim (NW US and Alaska, Western Canada) and ridging for the Eastern US and Canada. New England still can see troughiness however with this set up. We'll see how things look in the next couple of weeks for the 2nd half of the month. I am still expecting a change to cooler and stormier weather at some point in the second half of the month.

tron777 wrote: ↑Thu Sep 30, 2021 10:25 am

tpweather wrote: ↑Thu Sep 30, 2021 10:19 am Looking at the next few weeks and don't see much in the way of cold weather at all but you can get a damp cool day with an upper low. The cold is still over Alaska and will drop down to the northwestern part of the USA. Canada is where we tend to get cold weather and they are for the most part well above normal especially in the northern part of the country. I have no problem with this and sure they will get cold during October and hopefully that will bring some decent snows up there before the jet shifts to far south for the winter. Love the deeper snows up there as this can help in getting the cold to become even colder and when it moves southward it can stay cold longer.

Like I said in the Sept thread, thru mid October at the very least, I don't see much change to the overall pattern. Troughing where you said Tim (NW US and Alaska, Western Canada) and ridging for the Eastern US and Canada. New England still can see troughiness however with this set up. We'll see how things look in the next couple of weeks for the 2nd half of the month. I am still expecting a change to cooler and stormier weather at some point in the second half of the month.

I agree Les and there is a re-curving typhoon near Japan and this usually leads to ridging in the western USA and a trough in the central and eastern USA in about 10-14 days. This timing seems correct. If we get a busy pacific typhoon season over the next several months then expect a better shot of an early start to winter. The typhoon season is one that last all year but again it does have a peak usually in Sept and Oct. So there can be typhoons in the winter months but even without them you can get some nice storms in the western pacific.

tpweather wrote: ↑Thu Sep 30, 2021 12:08 pm

tron777 wrote: ↑Thu Sep 30, 2021 10:25 am

tpweather wrote: ↑Thu Sep 30, 2021 10:19 am Looking at the next few weeks and don't see much in the way of cold weather at all but you can get a damp cool day with an upper low. The cold is still over Alaska and will drop down to the northwestern part of the USA. Canada is where we tend to get cold weather and they are for the most part well above normal especially in the northern part of the country. I have no problem with this and sure they will get cold during October and hopefully that will bring some decent snows up there before the jet shifts to far south for the winter. Love the deeper snows up there as this can help in getting the cold to become even colder and when it moves southward it can stay cold longer.

Like I said in the Sept thread, thru mid October at the very least, I don't see much change to the overall pattern. Troughing where you said Tim (NW US and Alaska, Western Canada) and ridging for the Eastern US and Canada. New England still can see troughiness however with this set up. We'll see how things look in the next couple of weeks for the 2nd half of the month. I am still expecting a change to cooler and stormier weather at some point in the second half of the month.

I agree Les and there is a re-curving typhoon near Japan and this usually leads to ridging in the western USA and a trough in the central and eastern USA in about 10-14 days. This timing seems correct. If we get a busy pacific typhoon season over the next several months then expect a better shot of an early start to winter. The typhoon season is one that last all year but again it does have a peak usually in Sept and Oct. So there can be typhoons in the winter months but even without them you can get some nice storms in the western pacific.

Great post Tim and I fully agree. Saw a few pics on the internet also today of a big snow storm in eastern Siberia near the Bering Sea. Should continue thru tomorrow before winding down but it's there first big system of the season. So Eastern Siberia is starting to get some snow now and Alaska has been getting snow for the last couple of weeks. It will continue to snow at times for the next couple of weeks in these same areas until we see how the re-curving typhoon impacts the pattern. We should see a trough sometime after mid month as you've already said Tim.

After seeing the 12z GFS and other model trends... I am going to bring in POPS for our rain chances late Sat afternoon and honestly continue them thru next Saturday. It won't rain everyday over the next week but with that cut off getting stuck nearby, the rain chances will be there. Right now the heavier action comes Sunday into Monday and that is pretty high confidence. Exactly where the cut off low is positioned once it gets stuck, is the current model battle. Regardless, I think this system will have access to deep tropical moisture from the Caribbean getting pulled into this system via SE Flow off the Atlantic. So eventually in time... depending on where this system cuts off, the higher POPS for the middle to end of next week might be in our Eastern counties. That is not set in stone however as these cut off lows are tough to predict. Sometimes, we just need to take it day by day.

Then, by the 10th or so of Rocktober, we should see another warming trend with some 70s and perhaps even a few 80 degree readings occurring with ridging ahead of our possible after mid month change to cooler. We shall see, but those are my current thoughts.

12Z Euro coming in now and it continues to show only very light showers for late Sat and waits until Sunday morning onwards for the steadiest rainfall. Those with outdoor plans this weekend, make sure to do them on Saturday and early in the day if possible. If the Euro is right, a good chunk of Sat will be fine with chances late in the West. Probably dry until evening or overnight in the East. Sunday looks like a dreary day for just about everyone. Then next week I already talked about that, a daily chance thru next Sat thanks to the cut off low. Amounts and who has the best chance each day to be determined. I still like up to an inch of rain thru Monday at this time.

Euro looks pretty wet with another inch of rain Thurs / Fri of next week also should this solution pan out. If the set up is right a couple of inches of rain is not out of the question over the next week or so.

I agree about rainfall totals Les. With the late Saturday into early Monday I can see around an inch of rainfall. Then where does the upper low decide to reside will determine additional rainfall totals.Could be where Indy gets 0 Mon-Fri ,CVG gets 1/2 inch and Lexington 1 inch. Just way too early to throw out totals. Sometime next week you will see the models in their extended switch from above normal to near or below with one run, Certain weather conditions finally get imputed and that's when the models will make their changes. Glad we are on here to see this before the models.

Nice to see us on the same page Tim with this next system. DT's This Week in Weather is talking about Sam, and eventually some early winter thoughts too.

tron777 wrote: ↑Thu Sep 30, 2021 3:52 pm Nice to see us on the same page Tim with this next system. DT's This Week in Weather is talking about Sam, and eventually some early winter thoughts too.

Great Video and nice to see him talking about similar things that we are seeing on this forum. Again DT is a very good long term forecaster and he has more problems with short term forecasts. Remember last year Siberia was very mild with very little snow in October. That is usually a bad sign for us but what happened instead was some very heavy snows for the later part of November which is unusual and that help in getting us those few weeks in Feb that saved our winter. Getting an good start to winter is something we have not seen much of in recent years. Key point he made and I mentioned yesterday is keeping the La Nina at a weak stage because if it gets to strong it can control the weather.

tpweather wrote: ↑Thu Sep 30, 2021 4:23 pm Great Video and nice to see him talking about similar things that we are seeing on this forum. Again DT is a very good long term forecaster and he has more problems with short term forecasts. Remember last year Siberia was very mild with very little snow in October. That is usually a bad sign for us but what happened instead was some very heavy snows for the later part of November which is unusual and that help in getting us those few weeks in Feb that saved our winter. Getting an good start to winter is something we have not seen much of in recent years. Key point he made and I mentioned yesterday is keeping the La Nina at a weak stage because if it gets to strong it can control the weather.

I finally got a chance to watch the video and I totally agree Tim. If the guidance is right with the weak La Nina, weak PV, etc etc then chances are def increasing for early season fun. We've got a solid month or so to keep an eye on things but right now, I am happy with how things are progressing.

Ok snow fans, here is Mt. Washington today.

Now that is a gorgeous pic right there! Glad you found it JP! Hopefully within the next month or so, we will see our first flakes here.

Good morning all! Happy Friday to each of you and happy first day of Rocktober to you all! A nice day today with rain moving in late Sat afternoon in the West. Likely for all on Sunday. Lingering chances Monday, esp East. Tues and Wed are low chances with Thurs into Fri becoming likely once again. Still going with an inch of rain thru Mon with this first shot of heavier precip. Could see another 1/2 to 1" as well towards the end of next week. Temps will start in the 80s today and Sat then avg out in the low 70s for most of next week. Could see a day in the 60s should clouds and rain really do a number on temps. Lows should mainly be in the 50s thru the period.

54 here this morning.

tron777 wrote: ↑Fri Oct 01, 2021 6:58 am 54 here this morning.

That sounds nice. 68 down here in Greenville. Heading home on Saturday and will be in town until November 6th,

tpweather wrote: ↑Fri Oct 01, 2021 7:06 am

tron777 wrote: ↑Fri Oct 01, 2021 6:58 am 54 here this morning.

That sounds nice. 68 down here in Greenville. Heading home on Saturday and will be in town until November 6th,

Awesome! Glad you're coming back before the rain comes. Good move!

Hello October

On the opening day of October, the Russian Base of Vostok logged an astonishing minimum temperature of -79.4C (-110.9F) — this reading is just 0.6C above the world’s lowest temperature ever recorded in the month of October (set at the former Plateau Station, also in Antarctica).

And Australia


Alaska




King Salmon with a low temp Wed morning of 14F (-10.0C) sets a daily record for the fifth consecutive day. On Sunday the low of 13F (-10.6C) set a new September monthly record low temp. Previous record 15F (-9.4C) in 1983 and 2003

Great posts - and you def won't see this advertised on the MSM. Maybe we can finally cash in on a good winter here in the OV.

Bgoney wrote: ↑Fri Oct 01, 2021 8:09 am Hello October

On the opening day of October, the Russian Base of Vostok logged an astonishing minimum temperature of -79.4C (-110.9F) — this reading is just 0.6C above the world’s lowest temperature ever recorded in the month of October (set at the former Plateau Station, also in Antarctica).

Truly remarkable. MSM won't be reporting that.

cloudy72 wrote: ↑Fri Oct 01, 2021 8:21 am Great posts - and you def won't see this advertised on the MSM. Maybe we can finally cash in on a good winter here in the OV.

The pre game processes are starting up earlier then usual in our usual main cold air spots. Eastern Siberia, Alaska and Western Canada. I'd like to see that continue for a while then flip the switch to some better blocking on the Pacific side and bingo! We'll see how it goes. hopefully the Nina stays weak and the PV stays weak also. Good news should that happen.