General Weather Discussion - May 2015

[venture]

If the chat tends to stop, just refresh the page.

Moving to a rain threat not for most...if you are still ahead of the storms or in the southern/east areas of existing storms still keep an eye out as the LLJ increases.

[Bunty]

So is it pretty much wind/hail/flooding for the metro at this point? Any real tornado risk here?

Mike Morgan on channel 4 said the situation has improved enough so the chance of a tornado is near zero. But he is still worried about a significant risk for tornadoes on Saturday. I've been through a tornado in a car(fortunately car stayed upright and in the street) and far too close for comfort for another one, so I can understand your concern about tornadoes.

[venture]

Bulletin - eas activation requested
tornado warning
national weather service norman ok
659 pm cdt fri may 8 2015


the national weather service in norman has issued a


* tornado warning for...
Northern seminole county in east central oklahoma...
Southeastern lincoln county in central oklahoma...
Northeastern pottawatomie county in central oklahoma...


* until 730 pm cdt

* at 659 pm cdt...a severe thunderstorm capable of producing a
tornado was located 5 miles west of little...moving east at 25 mph.


Hazard...tornado and golf ball size hail.


Source...radar indicated rotation.

[venture]

[venture]

[pw405]

This storm dumped some extremely impressive rainfall amounts. I was at home near 63rd & Meridian and I was astonished at how fast the rain was coming down. It was seriously mind blowing. Backyard had standing water everywhere. We'll have to wait next week for the official Drought Monitor to be updated, but I am going to go ahead and consider the drought over!

[Dessert Fox]

Is there a possibility of tomorrow being a washout like Anon talked about?

[Dustin]

The 30 day rain total from the mesonet is just mind blowing. Who ever is rain dancing, keep it up.

[venture]

Is there a possibility of tomorrow being a washout like Anon talked about?

Tomorrow shouldn't be a total wash out. We'll have early morning storms come through, but they should be out by noon to 1PM. That should allow us to dry out, destabilize again, and be reloaded for the afternoon/evening.

[Dustin]

When will the storms start popping up in central Oklahoma tomorrow?

[Anonymous.]

We will have a wave of garbage convection developing out in the TX PH over the next 3 hours. This will shove off east quickly and into OK by morning. Then we will see how we do on burning off the cloud deck and destabilizing. Really just depends on how tomorrow early day pans out.

1. Looks like we should have a solid 3-4 hours of baking in the sun close to 80F and dews in the 66-70F range. This would be a worse case scenario as the dryline would fire on the TX/OK border and march however many monster cells eastward. Heavy rain a guarantee, hail likely, tornadoes possible.

2. Morning convection sticks around for long time and leave stubborn cloud deck in place for most of the day and we barely make 70F (like Friday). This scenario would likely result in the major action being up in NW OK into SW KS where the atmosphere will likely be better destabilized.

3. Either way, we could still get some nasty storms even if there is some cloud cover keeping a lid on things from going into the extreme category. We saw the last couple days that supercells can still get rowdy in a cloud covered 68F atmosphere.

4. We will have to watch for outflow boundaries from Friday's storms and the morning convection. these will be easier to find tomorrow on vis sat and wind profiles.

[venture]

Moderate risk pulled out of most of Oklahoma. Mostly slight risk, but do have an enhanced risk over thethe Northwest. All depend on how much ongoing convection we have and how soon it clears up. Stay aware.

[BoulderSooner]

Thanks to both of you

[David]

Any recommendations on whether it would be a good/bad idea to take a partial day trip down to Ardmore and back for the Mother's day weekend in the middle of all of this?

[s00nr1]

The threat for high-end severe in the OKC metro has diminished significantly. Main threat today will continue to be flooding with any storms that move through the area. Higher tornado threat still exists in far west and northwest OK where some clearing and destabilization could occur following passage of morning convection.

[venture]

[venture]

ENHANCED RISK today west of a line from Cherokee to El Reno to Chickasha to Marietta.
SLIGHT RISK today west of a line from Nowata to Muskogee to Sigler to near Broken Bow.
MARGINAL RISK for the area east of the slight risk area.

Complete mess today with on going convection. One batch of moderate rain moving through into the I-35 corridor from Central to southern OK. Some small hail and occasional wind gusts possible with this. Next area is back in NW OK through the TX Panhandle. Severe Thunderstorm watch is already out for this area, but none of these storms are current severe.

Atmosphere is generally stable at the surface outside of Southwest OK. A clearing slot is moving into SW OK that should overspread much of it ahead of the line in the Panhandle. This clearing should reach Central OK by early afternoon. Depending on the evolution of the line in the Panhandle and the extra track it takes will impact how much heating we get through the afternoon. If it is relatively short lived, then severe weather chances will remain pretty meager later this afternoon and evening.

HRRR and 4km NAM want to destabilize this area, with some of the CAPE values getting quite extreme. I'm not sold on that at this time, but we have a lot of energy coming through so it could be possible. Today is really going to be about getting to the nitty gritty and really watching every little possible feature and evaluate the risk on a very localized scale. This means looking for boundaries, watch how far south the TX PH storms build, what type of air mass are surface winds originating from, how are the wind fields above the surface at any given point, etc.

So here is my general thought for Oklahoma today. If we can keep this clearing slot roughly in tact and move it NE into the Central OK, and take the storms in the TX PH and move them more NE without any additional development to the south...then there will be the possibility for one or two supercells to get going in that unstable atmosphere in the clearing slot. The key thing is that area needs to stay mostly clear, we can't have any convective debris or anvil blow off overspread it, and the moisture fetch from the South and Southeast needs to remain relatively untapped. At present we do have a fairly large blob over Decatur and Denton which can impact things, so that is going to be a strike there.

So right now we need to watch the line in the TX PH which hasn't been developing much further south at all for the last our. There are some cumulus clouds trying to go up in the clear slot already, so that might complicate things if we get convective garbage filling it in. Today definitely doesn't look as widespread as what it could have been, but that doesn't mean we won't get something significant if it can get established. It only takes one to make it a bad day.

[Anonymous.]

Line still building south. It is clearing relatively quickly behind it, but this stuff will be over the state during peak heating so it probably will not matter.


The line is definitely falling apart and downtrending in intensity. If the remnants shove off and the clouds shear off to the NE, then we could attempt at clearing.

[venture]

Should start seeing peaks of sun into the Metro area soon. Thinning clouds moving into Canadian and far western Oklahoma, Cleveland and McClain counties. Line in the panhandle which is the main wild card right now is still on the downward trend. One storm near Childress is trying to hang on, but it has been trending down here the last few scans.

Outflow boundary being kicked out ahead of these will need to be monitored for later. Also we need to see how the southern extent of the thick cloud cover moves. Right now it has been trending ENE. Current trajectory would have the southern edge of this cloud deck stay north of a Quanah - Chickasha - Seminole line. Putting the area south of that in sun for much of the afternoon. Granted there is CU going up and weak showers already polluting part of that area, but nothing ramping significantly. We also could see this outflow trigger additional high based activity well into this clear slot.

So we just need to watch it. Today is all about the fine details and there are a lot of them to evaluate.

[venture]

Updated Day 1 - Enhanced Risk for all of Southern OK and also Western OK.

...SRN PLNS TO ARKLATEX TODAY/TNGT...
ANOTHER COMPLEX CONVECTIVE SCENARIO IS EXPECTED TO UNFOLD OVER THE
SRN PLNS...WITH SEVERAL AREAS OF ENHANCED CONCERN. FIRST...HEATING
ALONG DIFFUSE W-E OUTFLOW BOUNDARY OVER N CNTRL/NE TX EWD INTO THE
ARKLATEX MAY BE THE FOCUS FOR SCTD SUPERCELLS/SUPERCELL CLUSTERS
LATER TODAY INTO TNGT AS SFC HEATING DESTABILIZES AMPLY SHEARED
REGION. COUPLED WITH WEAK ASCENT PROVIDED BY AN APPARENT UPR IMPULSE
AND ASSOCIATED BAND OF ENHANCED SWLY FLOW ALOFT...SETUP COULD YIELD
DMGG WIND/TORNADOES AND LARGE HAIL FROM STORM CLUSTERS WITH EMBEDDED
HP-TYPE STORMS/BOWING STRUCTURES.

FARTHER S AND W...OTHER STORMS MAY INITIATE WITH DIURNAL HEATING
ALONG TRAILING DRY LINE/LEE TROUGH SEGMENTS OVER THE TX HILL
COUNTRY. AND...ONE OR TWO SUPERCELLS MAY ARISE SE OF EXISTING
STORMS NOW NEAR CDS. THIS ACTIVITY WILL ALSO HAVE THE POTENTIAL TO
SPAWN A COUPLE TORNADOES...IN ADDITION TO VERY LARGE HAIL AND
/MAINLY NARROW/ CORRIDORS OF DMGG WIND. LATE TNGT AND EARLY SUN...A
SEPARATE AREA OF SVR STORMS /MAINLY WITH LARGE HAIL AND LOCALLY DMGG
WIND/ MAY ARISE ALONG TRAILING SW PART OF LEE TROUGH/PACIFIC FRONT
AS THE BOUNDARIES BECOME QSTNRY OVER SW TX/THE TX BIG BEND.

[venture]

The national weather service in norman has issued a


* severe thunderstorm warning for...
Northern cotton county in southwestern oklahoma...
Comanche county in southwestern oklahoma...
Southwestern grady county in central oklahoma...
Northwestern stephens county in southern oklahoma...


* until 1245 pm cdt


* at 1153 am cdt...severe thunderstorms were located along a line
extending from 7 miles northwest of cookietown to 4 miles east of
walters...moving north at 35 mph.


Hazard...ping pong ball size hail and 60 mph wind gusts.

[venture]

The national weather service has extended severe thunderstorm
watch 148 to include the following areas until 2 pm cdt this
afternoon

in oklahoma this watch includes 10 counties

in central oklahoma

canadian cleveland grady
mcclain oklahoma

in southern oklahoma

garvin jefferson stephens

in southwest oklahoma

comanche cotton

in texas this watch includes 1 county

in northern texas

wichita

[Anonymous.]

Just too much lift, storms keep developing over the clearing skies. Looks like this is how most of today will go. Great rainfalls, just watch out for urban flooding.

[venture]

Keep an eye on the storm near Corum/Empire City moving towards Duncan. No blockage to the south and it is rotating at this time with an inflow area.

[Anonymous.]

HRRR hinting at dryline firing late.