General Weather Discussion - April 2015

[Achilleslastand]

Being that ive had 4 roofs replaced since 1998 I can do without the hail/tornadoes, any rainfall especially heavy I welcome.

[venture]

Latest HRRR has storms moving into SW OK by 5-7PM tonight.

[Anonymous.]

Latest refresh isn't as bullish as last.

Seems to think the activity in SE KS is going to be pretty crazy. Looks like potential for severe flooding is likely up there.

[venture]

HRRR is shifting south with the latest run. Currently have some CU starting to form in Major and Garfield counties. This would line up with HRRR's new initiation point...



It also pops SW OK by 7PM as well...

[venture]

CU starting to go up in the area of interest on HRRR.

[Anonymous.]

Dam, V. You come post everything just minutes before I come to post it.

[Anonymous.]

Faint CU field developing in NW TX now.

[venture]

Dam, V. You come post everything just minutes before I come to post it.

Great minds and all that! :-D

[venture]

Watch Likely Soon

[venture]

Update showing some towers going up now in Texas...based off of the shadows.

[venture]

Might finally have a tower or two breaking through up north, but those high level clouds are rolling in over them now.

[Easy180]

You might have already mentioned this but what does it mean for tomorrow if nada happens tonight?

[venture]

You might have already mentioned this but what does it mean for tomorrow if nada happens tonight?

Mentioned it a bit in the chat a bit ago...it definitely throws the NAM forecast off since there won't be the big outflow boundary to be a focus tomorrow. It also means the atmosphere won't be worked over and still primed.

With that said, we have to see if we get convection to fire late tonight or tomorrow morning/early afternoon. One ensemble had a bunch of storms pop early from the Metro on to the North and through Kansas. It then cleared out for a few hours during peak heating and then lit up the entire dry line. So needless to say...still a very evolving situation.

[venture]

Well the front in Kansas is finally going up. Strongest cell is south of Fredonia.

[venture]

Confirmed tornado with the southern storm in Kansas.

[ultimatesooner]

looks like i might be right in the middle of it in Wichita tomorrow, working about an hour north of here in Hutchinson tomorrow afternoon - goal is to get out of there early enough to be at the hotel before they get here

[Anonymous.]

That SE KS cell could be storm of the year already. Stationary, good inflow, open land.

[venture]

That SE KS cell could be storm of the year already. Stationary, good inflow, open land.

That thing appears to be cycling back up as well...it has to be loving the energy available to it.

[venture]

[venture]

Wednesday Discussion....

Still questions on how Wednesday will evolve. Long lasting supercell over SE Kansas has started to cause some minor back building. Earlier models had forecast a complex to form and dive through NE OK overnight. Still yet to see if this happens, but if it does it can lay down an outflow boundary I had discussed earlier. Near term through the overnight, slight chance of severe weather in the extreme northeastern OK counties with this supercell if it makes the border. It has been tornadic for nearly 2 hours now with sporadic touchdowns - but it just hasn't really moved a lot.

Model guidance is still a bit mixed on how things will evolve tomorrow...

4KM NAM - Isolated/scattered storms form around 3PM over the Western Metro and move to the NE. By 5PM additional storms form in North Central OK along the front. By 6PM additional storms fire along the dryline in Southwest OK, while on going severe weather in Northeast OK. It currently projects the dryline activity will fade out by 10PM before reaching Central OK. Atmosphere is still projected to get highly unstable with CAPE values around 4000 j/kg ahead of the Dryline. Significant tornado parameters would be moderate over the Central 1/3rd of Oklahoma by 7PM and will increase with the LLJ in the evening - which could be important if we see activity around or after sunset. The NAM also doesn't really sharpen the dryline that much and keeps it pretty far west. We'll be in the soup until about 1PM on Thursday when the front crashes through.

GFS - Similar story on dryline placement, but it moves the front in about 3 hours earlier. Precip wise it has storms over NE OK earlier in the day that eventually fade out by late morning. New development by 4PM along the cold front from about Clinton up to Ponca City, but keeps most activity north of I-40 and does not initiate the dryline. Instability ahead of the dryline still very high with CAPE around 3000 j/kg.

RAP - Dryline a bit further east into OK on the RAP by 4PM...running from Alva down to Altus. Precip wise it initiates showers/storms along/near I-35 by Noon, moves those out, and then another batch along the dryline from NW OK south through Texas. Instability is similar to NAM with 4000 j/kg all ahead of the dryline with minimal CIN by mid afternoon. 4PM is the extent of its forecast window for now, so can't go any further.

SPC's Storm-Scale Ensemble (SPC SSEO 3SP-1KM-REFL40) is a nice tool as it allows you compare several models at once. Still waiting for the 00Z update, but 12Z did initiate all along the dryline with most of its members. So taking that into consideration, I do expect the dryline to fire and also see storms in Northern OK early in the afternoon. Severe weather is pretty much likely with any storms that do go up. Those that remain isolated and don't have interference from other storms will be most likely to have very large hail and tornadoes. Keep in mind, even if coverage isn't significant, it just takes one cell to cause a bad day.

[venture]

Metro upgraded to an enhanced risk and an upgrade to moderate may be needed tomorrow. Slight risk expanded south. Entire enhanced risk is under a 10% hatched area for tornadoes.

[PennyQuilts]

If I read it right, they've tightened up the area of enhanced risk to barely exclude most of the metro? I'm very interested in what our weather geniuses have to tell us about the day. It been a beautiful, cool morning (I've been up and outside before dawn)but notwithstanding the cool breezes, I feel some sticky soupy stuff hovering between wafts.

[Anonymous.]

Super rich moisture in place today. Could have some garbage convection develop in SW OK this morning and move across area this afternoon. This would help keep a leash on some things for tonight.

However, it looks like multiple supercells will be firing late afternoon into evening and march from W OK into C and N OK. Models are having a tough time, but actually some indication of the dryline firing multiple rounds.

If things get clear here in main body of the state and we start cooking under the sun, I could see a MDT risk upgrade.

[venture]

If I read it right, they've tightened up the area of enhanced risk to barely exclude most of the metro? I'm very interested in what our weather geniuses have to tell us about the day. It been a beautiful, cool morning (I've been up and outside before dawn)but notwithstanding the cool breezes, I feel some sticky soupy stuff hovering between wafts.

This says it best right now...

Rick Smith @ounwcm

Don't get hung up on exact placement of outlook lines today! There are fuzzy edges on those lines. Storms don't know they're there! #okwx

[LocoAko]

Super rich moisture in place today. Could have some garbage convection develop in SW OK this morning and move across area this afternoon. This would help keep a leash on some things for tonight.

However, it looks like multiple supercells will be firing late afternoon into evening and march from W OK into C and N OK. Models are having a tough time, but actually some indication of the dryline firing multiple rounds.

If things get clear here in main body of the state and we start cooking under the sun, I could see a MDT risk upgrade.

Definitely. Both the NSSL and SPC WRF have those multiple rounds -- a lot more of a complicated evolution than I perhaps originally expected.