General Weather Discussion - May 2016

[Anonymous.]

Obviously, this gets muddier the further out you go. General synopsis, be aware.

Sunday evening - W OK (see PH) dryline action

Monday evening - C OK dryline action

Tuesday evening - C (eventual E) OK front/dryline action

Wednesday evening - E OK front action

Thursday - E (maybe C) OK action

Friday - W and C OK action

Saturday - C and E OK action

Sunday - C and E OK action

Further out - looks like general severe weather chances continue into June.

[AP]

Someone please tell me the likelihood of rain on June 4th. I'm getting married that day and I'm #Praying4Rain

[Anonymous.]

So you want rain? Models are garbage that far out, but as it stands today, there is indeed rain/storms in OK per GFS.

[AP]

Kind of jokingly. I bought my fiance's engagement ring at BC Clark and they do the Pray4Rain promotion. I'm not super serious but noticed that accuweather predicted rain on that day. Might be nice to get 5k of the ring back.

[Bellaboo]

So you want rain? Models are garbage that far out, but as it stands today, there is indeed rain/storms in OK per GFS.

He wants that ring paid for !

I know a couple that got some of theirs paid for.

[LakeEffect]

5k of the ring back.

OF the ring?

Hoping for rain just for you.

[AP]

Haha man, that promotion would be incredible! I meant "a full refund (excluding sales tax) of the purchase price of that ring, up to a maximum of $5,000"

[Soonerman12]

Hope your wife doesn't see this, you cheap bastard!





Ahh what am I saying I do the same damn thing lol

[bchris02]

Damon Lane is saying next week's severe threat will be the highest seen so far this year, and its pretty much every day all week. Mike Morgan seems to be going with Tuesday as being the biggest day with the highest threat in western Oklahoma. Not sure if too soon to try to pinpoint it like that, but I hope that is the case.

[Soonerman12]

Heads up, SPC has a 15% area for much of Oklahoma now for Thursday, DAY 7.

ZCZC SPCSWOD48 ALL
ACUS48 KWNS 200900
SPC AC 200900

DAY 4-8 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0400 AM CDT FRI MAY 20 2016

VALID 231200Z - 281200Z

...DISCUSSION...
AN INCREASINGLY SEVERE-CONDUCIVE PATTERN IS EXPECTED THROUGH EARLY
NEXT WEEK...ESPECIALLY ACROSS PARTS OF THE CENTRAL/SOUTHERN PLAINS
TO THE MO VALLEY/MIDWEST. THIS WILL GENERALLY BE ATTRIBUTABLE TO
SEMI-PERSISTENT TROUGHING WEST OF THE ROCKIES AND
NORTHWARD-DEVELOPING LOW-LEVEL MOISTURE...WITH A PARTICULARLY
MOISTURE-RICH/STRONGLY UNSTABLE AIR MASS EXPECTED ACROSS THE
SOUTH-CENTRAL PLAINS IN THE ABSENCE OF LOCALIZED CONVECTIVE
OVERTURNING.

CURRENT INDICATIONS ARE THAT AT LEAST CATEGORICAL SLIGHT RISKS ARE
PLAUSIBLE EACH DAY THROUGH AT LEAST THE MIDDLE PART OF THE WEEK /DAY
7 THURSDAY/. IT SHOULD ALSO BE NOTED THAT GRAPHICAL RISK ADJUSTMENTS
WILL UNDOUBTEDLY BE NEEDED AS MESOSCALE DETAILS ARE RESOLVED.

DAY 4/MONDAY...WHILE RESIDUAL DAY 3 CONVECTION AHEAD OF A COLD FRONT
CASTS SOME UNCERTAINTY...SEVERE THUNDERSTORMS COULD OCCUR AS FAR
NORTH AS MN/IA. A SOMEWHAT MORE CERTAIN SEVERE RISK IS EXPECTED
ACROSS THE SOUTH-CENTRAL PLAINS INCLUDING PARTS OF KS/OK INTO
NORTH/WEST TX NEAR THE DRYLINE.

DAY 5 TUESDAY...INCREASING/NORTHWARD RETURNING LOW-LEVEL MOISTURE
AHEAD OF A COLD FRONT/DRYLINE...IN CONJUNCTION WITH A
LOWER-AMPLITUDE TROUGH OVER THE CENTRAL PLAINS...SHOULD LEAD TO
SEVERE THUNDERSTORMS RISKS ACROSS PARTS OF THE CENTRAL/SOUTHERN
PLAINS TO LOWER/MIDDLE MO VALLEY.

DAY 6/WEDNESDAY...AS THE DEAMPLIFYING TROUGH OVERSPREADS THE UPPER
MIDWEST/GREAT LAKES...SEVERE THUNDERSTORMS COULD OCCUR ACROSS PARTS
OF WI/IL/MI AND MIDDLE MS VALLEY/OZARKS... SOUTHWESTWARD TO NEAR THE
SOUTHERN PLAINS DRYLINE VICINITY WHERE THE SEVERE RISK MAY BE MORE
ISOLATED/CONDITIONAL WITHIN A VERY UNSTABLE ENVIRONMENT. WHILE
SEVERE THUNDERSTORMS CAN BE EXPECTED ON WEDNESDAY...THE POSSIBILITY
OF EARLY-DAY CONVECTION ACROSS THE MIDWEST AND RELATED MESOSCALE
UNCERTAINTIES CURRENTLY PRECLUDES A GRAPHICALLY DEPICTED SEVERE
RISK.

DAY 7/THURSDAY...WHILE CONFIDENCE IN SPATIAL DETAILS IS NOT OVERLY
HIGH...EARLY INDICATIONS ARE THAT A NORTHEASTWARD-EJECTING SOUTHERN
STREAM TROUGH IN CONJUNCTION WITH STRENGTHENING WESTERLIES ALOFT
WILL OVERSPREAD A VERY MOIST/UNSTABLE WARM SECTOR ACROSS THE
SOUTH-CENTRAL PLAINS TO MO VALLEY/MIDWEST.

..GUYER.. 05/20/2016

[TheTravellers]

Someone please tell me the likelihood of rain on June 4th. I'm getting married that day and I'm #Praying4Rain

Congrats, we'll be celebrating our 22nd anniversary that day also (most likely in a completely different way than you're going to be celebrating, though )!

[bchris02]

Very nervous about next week.

Is there any good news i.e. anything at play to prevent this from being similar to the final week of May in 2013?

[ou48A]

There were predictions made many weeks ago by some of the TV guys that the last part of May would be super active for sever weather….. Looks like they may have been right.

[jn1780]

Very nervous about next week.

Is there any good news i.e. anything at play to prevent this from being similar to the final week of May in 2013?

I wouldn't really be too nervous about it. Just have to take one day at a time.

[SoonerDave]

Very nervous about next week.

Is there any good news i.e. anything at play to prevent this from being similar to the final week of May in 2013?

You are taking for granted the idea it will be "similar" to May 2013. Every "May" has the potential to be similar to every other "May", because May is generally storm season...In all honesty, no snarkiness or disrespect intended, but if the advance forecasts give you that much anxiety, I think I'd stop paying them so much attention.

That is, someone could come on here and post a note saying "oh, yeah, NOTHING will happen next week," and the peace it might induce would be just as artificial as the angst generated by someone *else* showing up and saying "massive storm outbreak guaranteed!" Just take it a day at a time.

[bchris02]

You are taking for granted the idea it will be "similar" to May 2013. Every "May" has the potential to be similar to every other "May", because May is generally storm season...In all honesty, no snarkiness or disrespect intended, but if the advance forecasts give you that much anxiety, I think I'd stop paying them so much attention.

I find the more I know, the better. What causes the most anxiety, at least for me, is a very muddy forecast combined with hype from the TV meteorologists. I have really appreciated David Payne's calmer forecasts this year. Tonight's was excellent. Another TV meteorologist who I will not name compared this upcoming week to the last week of May in 2013. I don't see how that does anybody any good and all it does is incite panic.

I would like to learn more about the models like GFS, NAM, etc myself and also learn how to interpret weather balloon soundings.

[LocoAko]

I find the more I know, the better. What causes the most anxiety, at least for me, is a very muddy forecast combined with hype from the TV meteorologists. I have really appreciated David Payne's calmer forecasts this year. Tonight's was excellent. Another TV meteorologist who I will not name compared this upcoming week to the last week of May in 2013. I don't see how that does anybody any good and all it does is incite panic.

I would like to learn more about the models like GFS, NAM, etc myself and also learn how to interpret weather balloon soundings.

Just stick with the NWS and SPC then. They know what they're doing and have much less incentive to hype. Not everything is going to wind up like May of 2013. The forecast for this week is muddy because there's going to be extreme instability present and a bunch of pieces of energy ejecting through the Plains throughout the week. The wind fields don't look super top-end on any of the days (for now), but they do look more than sufficient for supercells and possibly tornadoes for most of the week. Just take it a day at a time and don't always assume the worst. You'd be surprised how much has to go right to get a tornado outbreak... it's not as easy as people make it sound. :P

[bchris02]

You'd be surprised how much has to go right to get a tornado outbreak... it's not as easy as people make it sound. :P

Thanks for letting me know about the wind fields as that was something I was wondering about. Where can I get this information and what is conductive to a high-end outbreak and what isn't? This year, and reading coverage leading up to that PDS day a few weeks ago has taught me that. You have to have instability + shear + updraft + cap not too weak or strong + dry line in right spot + no/little rain or cloudcover throughout the day are all necessary. Boundaries and triple point location are also important and in multi-day setups like what is coming next week, what happens one day can effect what happens the next. If one of these things isn't there or not positioned just right, a high-end forecast can be a bust. For instance, too much instability and too weak of a cap can cause explosive development that conglomerates into a huge mess that doesn't pack the punch of discreet tornadic supercells.

[SoonerDave]

Thanks for letting me know about the wind fields as that was something I was wondering about. Where can I get this information and what is conductive to a high-end outbreak and what isn't? This year, and reading coverage leading up to that PDS day a few weeks ago has taught me that. You have to have instability + shear + updraft + cap not too weak or strong + dry line in right spot + no/little rain or cloudcover throughout the day are all necessary. Boundaries and triple point location are also important and in multi-day setups like what is coming next week, what happens one day can effect what happens the next. If one of these things isn't there or not positioned just right, a high-end forecast can be a bust. For instance, too much instability and too weak of a cap can cause explosive development that conglomerates into a huge mess that doesn't pack the punch of discreet tornadic supercells.

A "strong cap" means the atmosphere won't allow the convection necessary for storms to form and lift. The stronger the cap, the less likely storms are able to form. When you have a strong storm system coming in, it can provide vertical "forcing" sufficient to "break the cap." That's where you hear mets talk about "keeping a lid" on storms...big cap, few if any storms can form.

Early morning storms can mess up a forecast because they "beat up" and stabilize the atmosphere sometimes long enough to prevent afternoon heating from *de*stabilizing it enough to facilitate later storm development.

[ou48A]

Thanks for letting me know about the wind fields as that was something I was wondering about. Where can I get this information and what is conductive to a high-end outbreak and what isn't? This year, and reading coverage leading up to that PDS day a few weeks ago has taught me that. You have to have instability + shear + updraft + cap not too weak or strong + dry line in right spot + no/little rain or cloudcover throughout the day are all necessary. Boundaries and triple point location are also important and in multi-day setups like what is coming next week, what happens one day can effect what happens the next. If one of these things isn't there or not positioned just right, a high-end forecast can be a bust. For instance, too much instability and too weak of a cap can cause explosive development that conglomerates into a huge mess that doesn't pack the punch of discreet tornadic supercells.

Many people mistake a 30% or 40% of rain as a low chance for tornadoes when in fact many of our worst tornadoes occur with this percentage of rain… it’s because the supercells stay discrete, few in number and pull in all the surrounding energy.

[SoonerDave]

Thanks for letting me know about the wind fields as that was something I was wondering about. Where can I get this information and what is conductive to a high-end outbreak and what isn't? This year, and reading coverage leading up to that PDS day a few weeks ago has taught me that. You have to have instability + shear + updraft + cap not too weak or strong + dry line in right spot + no/little rain or cloudcover throughout the day are all necessary. Boundaries and triple point location are also important and in multi-day setups like what is coming next week, what happens one day can effect what happens the next. If one of these things isn't there or not positioned just right, a high-end forecast can be a bust. For instance, too much instability and too weak of a cap can cause explosive development that conglomerates into a huge mess that doesn't pack the punch of discreet tornadic supercells.

There's a great example of the variability of these forecasts in the Day 3 (Monday) SPC summary from NOAA. Look here (emphasis mine):

INITIALLY...CURRENT THINKING IS THAT A MCS MAY BE ONGOING/MOVE
SOUTHEASTWARD ACROSS THE LOWER MO VALLEY/OZARKS MONDAY MORNING. THIS
POSSIBLE MCS CASTS UNCERTAINTY ABOUT THE DEGREE OF DESTABILIZATION
IN ITS WAKE...PARTICULARLY WITH NORTHWARD EXTEND ALONG THE FRONT
FROM KS INTO EAST-CENTRAL NEB...WITH SPECULATIONS THAT RELATED
OUTFLOW/DIFFERENTIAL HEATING COULD INDUCE AN EFFECTIVE TRIPLE POINT
SOMEWHERE ACROSS KS. CURRENT THINKING IS THAT GREATEST SEVERE RISK
MONDAY AFTERNOON/EVENING WILL EXIST FROM THIS POSSIBLE TRIPLE POINT
VICINITY SOUTHWESTWARD ACROSS WESTERN PORTIONS OF OK AND TX IN
VICINITY OF THE DRYLINE...WHERE MIDDLE/UPPER 60S F SURFACE DEWPOINTS
WILL CONTRIBUTE TO STRONG DESTABILIZATION /3000+ J PER KG MLCAPE/.
SUPERCELLS CAPABLE OF LARGE HAIL AND FEW TORNADOES CAN BE EXPECTED
ESPECIALLY LATE AFTERNOON THROUGH EARLY/MID-EVENING...WITH SOME
POTENTIAL FOR ONE OR MORE MCS/S TO EVOLVE MONDAY NIGHT WITH A
DAMAGING WIND THREAT.

While the overall discussion is consistent with the general advisory about the potential for severe weather Monday, look at a couple of very important qualifiers I've bolded a couple of things:

1. "CURRENT THINKING" - Much of the *gross* analysis is provided by the models, GFS, NAM, EURO. But despite the advance of computer-based algorithmic simulation of weather, there's a great deal of thought that goes into the *fine-grained* analysis in these forecasts. It's the "current thinking." That's based on the expertise of the people who assemble the forecasts, their review of data beyond the models, air flow, moisture, the whole schmear. You *have* to have this kind of analysis, because relying solely on the models will Get You In Trouble. They're *one* important tool in weather forecasting. And, to a degree, its instinctive, its experience-based, and as such necessarily can't be reduced to an algorithm. There may be a general consensus among forecasters, but it's not merely a recitation of what the models show.

2. "An MCS....[leads to] uncertainty about destabilization" - That's the met's $10 way of saying crapvection throws a huge monkeywrench into...everything. It's precisely what we were talking about before - if you get an early morning/mid-day system that beats up the atmosphere early, it may have limited or no time to "recover" and become sufficiently unstable such that all the *later* convection and moisture and airmass collision can happen. Again, that's something *very* hard to model. But the mets who interpret the models also know all to well about crapvection and know that mitigates the certainty of any such forecast.

All this is to say these forecasts even two or three days out have to be taken for what they are - advisories that combine the expertise of trained meteorologists (which I am most certainly not, although I love to try and study it) with all the tools at their disposal - the models and satellites and hodographs and wind graphs and everything else. There are so many variables, it's precisely what makes the severe forecasting job so incredibly difficult. It's like predicting how a leaf will fall from a tree - you know eventually it will hit the ground, but the path it takes to get there may be anything but a straight line. And the folks who insist things are "guaranteed" more than a few days out usually have another agenda (ratings chief among them).

So what do we take from this Day 3 outlook? Severe storms are possible in NW OK, and early storms make the forecast going N/NE of there much trickier. Bottom line? Just keep aware of what's up.

[jn1780]

Looks like a bumpy week. Looks more like an isolated tornado threat Monday and Tuesday. Thursday or Friday could see a more elevated threat depending on how things evolve.

[bchris02]

Looks like a bumpy week. Looks more like an isolated tornado threat Monday and Tuesday. Thursday or Friday could see a more elevated threat depending on how things evolve.

Yeah Thursday and Friday especially look like they could be the big show depending on how things set up.

What's interesting is I haven't heard a lot of details or threat levels from the TV meteorologists this time. They seem to be taking a "wait and see" approach, which is different from the way they have been hyping it and issuing tornado indexes a week out all season long. Is it simply because its a muddy forecast?

[SoonerDave]

Yeah Thursday and Friday especially look like they could be the big show depending on how things set up.

What's interesting is I haven't heard a lot of details or threat levels from the TV meteorologists this time. They seem to be taking a "wait and see" approach, which is different from the way they have been hyping it and issuing tornado indexes a week out all season long. Is it simply because its a muddy forecast?

Because being that alarmist about conditions six days away just doesn't really help anyone. The situation that far out just isn't that fixed.

[Anonymous.]

This morning's stuff is clearing out. Should have a solid day of sun and heating things up to a very unstable environment.

Models fire storms up in the S TX PH and into WC OK later today and move them off to the east in these sort-of complexes. It will likely be similar to yesterday where they start as individual HP supercells and evolve into clusters with embedded supercells. Anything remaining isolated will pose greatest threats.

Thursday and Friday look like potential PDS type of days, at this time.