Absolute Vorticity

tron777 wrote: ↑Tue Mar 21, 2023 12:45 pm 12Z GFS still going with almost 4" of rain at CVG.

I know the euro and cmc have been somewhat lower than the gfs but higher than the last nam run.

CMC has a solid 2-3" for most folks.

12Z Euro is just shy of 3.5" at CVG.

Les,was not sure the NAM had gone all the way out and that is why totals are lower. I know it stops at 84 hours and we may be talking at least 90-96 hours before system is done. Just one thought or the Nam is doing what the Nam does at 84 hours.

I apologize for my lack of knowledge when it comes to weather but I have never seen this. On my phone it came across a severe weather alert today when clicking on the button it proceeds to say Hydrologic Outlook effective March 21 thru March 22 then proceeds to say we are in a Active weather pattern that will bring series of storms bringing heavy rain Thursday night into Friday which are even the dates mentioned lol. I know the threat is real from all of you guys but I have never heard of this type alert is this a new thing?

Pepper wrote: ↑Tue Mar 21, 2023 3:16 pm I apologize for my lack of knowledge when it comes to weather but I have never seen this. On my phone it came across a severe weather alert today when clicking on the button it proceeds to say Hydrologic Outlook effective March 21 thru March 22 then proceeds to say we are in a Active weather pattern that will bring series of storms bringing heavy rain Thursday night into Friday which are even the dates mentioned lol. I know the threat is real from all of you guys but I have never heard of this type alert is this a new thing?

I've seen weather service offices issue hydrologic outlooks before heavy rain events occur. Usually though, I never see alerts issued for them, only flood watches or flood warnings. What I mean is your phone going off for example. It should for a flood watch or warning but not sure why it went off for a hydrologic outlook. That is the part that I cannot answer.

tpweather wrote: ↑Tue Mar 21, 2023 2:45 pm Les,was not sure the NAM had gone all the way out and that is why totals are lower. I know it stops at 84 hours and we may be talking at least 90-96 hours before system is done. Just one thought or the Nam is doing what the Nam does at 84 hours.

Correct Tim. NAM stopped at Fri evening around 7pm.

Thanks Les and wanted to make sure I was correct on the nam timing. The upcoming system from late Thursday through Saturday may be one of the biggest in terms of rainfall we see all year. More and more data continues to show the front stalling near us early Friday. Again a general 1-3 inches seems very likely but amounts more in the 2-4 and a tad more seems possible as well. Many times we get these systems and a few folks really get hit hard while the rest of the area is on the lower end. There will no doubt be someplace that exceeds 5 inches if the current trends continue. That area may be near the Ohio River and that does bring up the flood threat a little more next week. Localized flooding will still be the issue later this week and folks who live near the streams and rivers are well versed in this happening in most spring seasons.

tpweather wrote: ↑Tue Mar 21, 2023 4:01 pm Thanks Les and wanted to make sure I was correct on the nam timing. The upcoming system from late Thursday through Saturday may be one of the biggest in terms of rainfall we see all year. More and more data continues to show the front stalling near us early Friday. Again a general 1-3 inches seems very likely but amounts more in the 2-4 and a tad more seems possible as well. Many times we get these systems and a few folks really get hit hard while the rest of the area is on the lower end. There will no doubt be someplace that exceeds 5 inches if the current trends continue. That area may be near the Ohio River and that does bring up the flood threat a little more next week. Localized flooding will still be the issue later this week and folks who live near the streams and rivers are well versed in this happening in most spring seasons.

I'm leaning towards 2-3" as being a good forecast this far away from the event. This doesn't count tonight into tomorrow's light rain by the way. I am counting Thurs - Sat for the 2-3" idea. Amounts in the 3-5" range also cannot be discounted. I am not going that high yet. I'd like to see another couple of runs before going all in.

I saw on the WHIO7 wx segment at noon that the rain amounts forecast map had Greenville e.g. for 2.98"

Of course it'll change but just sharing what today's noon cast showed.

Currently 54 here in my area.

WPC afternoon update



Expect heavy rainfall over portions of the east-central U.S. late
this week as guidance continues to suggest that developing low
pressure emerging from the Plains will focus abundant moisture
along its trailing cold front and a leading wavy front. The new
day 4 (12Z Friday-12Z Saturday) Excessive Rainfall Outlook will be
quite similar to the previous day 5 issuance, reflecting only
minor adjustments for latest guidance with respect to a Slight
Risk area from parts of Arkansas/northern Louisiana northeastward
into southern Ohio and parts of West Virginia. Within this area,
guidance is starting to cluster toward heaviest rain totals being
along an axis from northeastern Arkansas into Kentucky or the Ohio
River. As low pressure continues northeastward Saturday into
early Sunday, some localized enhancement of rainfall is still
possible

3"+ per the boys is their thinking from the afternoon AFD with 30 knot winds on Sat and isolated severe wx. I know the low will be passing by thru IN to our NW so maybe the SE zones for isolated severe? I question CAPE with all of the rain and clouds before hand.

Rain is moving into the area as we speak. 0.25" or less tonight so not much of a concern. Just light to occasionally moderate rain. Then we get set Thurs thru Sat for the main corridor of rainfall which will come in several waves along a stalled out frontal boundary. We have a lot of moisture coming from two different sources. The Gulf is currently wide open for business and the next powerful low coming into S CA has an abundance of Pacific moisture via the STJ that will also feed into this system and everything will focus along and north of the frontal boundary for heavy rainfall.

Pretty impressive update from the WPC.

petty warm this week with highs around 60 winter is def over now.

Not much change overnight or for that matter the last several days. Mods have been consistent with rainfall amounts and locations . From north of Lexington to just north of Dayton a general 1-3” soaking through Saturday. Then within that corridor a 50-75 mile wide band of 4-5+” amounts.

Mammoth mountain resort one of many still breaking records. Over 800”at the summit and counting


Mammoth is the only ski resort on Earth in the 800-club and has North America’s deepest snowpack.


The official reading at Mammoth Lodge is 646″. The record is 668.5″ set in 2010/11. Right now, it’s not a question of ‘if’ but ‘when.’

Mammoth has only reached 600″ of snow once in the last ten years. In 2016/17, they got 617.5″ of snow.

The world record for a ski area is 1,140″ at Mt. Baker ski area, WA, in 1998/99.
Well known for its extended spring seasons, Mammoth has a long tradition of operating well into the summer months but has never announced an extension of this time this early in the season. Yesterday the resort announced it would stay open through AT LEAST July. In short, this will likely be the best spring skiing and riding the eastern sierra has ever seen.

Bgoney wrote: ↑Wed Mar 22, 2023 7:01 am Not much change overnight or for that matter the last several days. Mods have been consistent with rainfall amounts and locations . From north of Lexington to just north of Dayton a general 1-3” soaking through Saturday. Then within that corridor a 50-75 mile wide band of 4-5+” amounts.

I like 3" as a blend so to a speak. That should be a good avg for the region. GFS isn't backing down either from the more north / wetter solution.

Just a couple of hundredths here from the overnight activity. Scattered and not much to worry about until late Thurs thru Sat.

A moderate risk of excessive rainfall from the WPC. This is a 3 out of 4 on the scale.

My gauge picked up .18" from Tues night.

Prayerfully no backed up basements for any of the AV posters this late week.

My folks and I had installed an outtake piping system so prayerfully it'll do its job smoothly and be able to handle the steady rainfall.

We haven't had anymore backups since it was installed a few years ago.

My Mom ppd her appt for tomorrow AM in Lima and I'm glad she did due to the rounds of moderate / heavy rainfall forecast.

On the AccuWeather channel yesterday during the future rain transpiring forecast it showed a lot of yellow, orange and even red blend setting up around Wapakoneta, Bellefontaine and Lima e.g. for tomorrow AM.

Good Afternoon and made it to SC once again. Constant rain from south of Lexington to Greenville. Nothing heavy but steady. Heading for warm weather over the next few days with temps near 80 down here. Short trip and will be back on Sunday. Will get caught up on the latest trends for the late week system but from the posts not many changes.

Hey Tim... Glad you've made it safely! NAM has 2.31" at CVG and GFS 4.06" CMC still has a solid 3"+ from NKY on north.