January '10 Weather Discussion

[oknacreous]

18Z NAM continues the trend - more ice, less snow. I'm going to bump my freezing rain forecast for OKC up a bit, now 1/2 to 3/4" ice, 1-2" sleet, and around 2" snow.

[westsidesooner]

Okay so here is my doomsday forecast. LOL This is the best blend that I can go with right now.

Just like always my pc isn't picking up on the two images you have posted. I think it doesn;t like ".png" images. Could you give me a text version of what you think the westside (Bethany) area will recieve. In general of course.......and again thanks. I'm trying to decide if I need to go get a second gas can for the generator before the storm hits so I don't have to get out once it starts.......council groves can be a nightmare when the trees start crashing.

[venture]

I'll start putting them up at JPGs. :-P

That part of town, taking into consideration the 18Z NAM which still has a significant amount of precip falling (oknacreous, trying to go as conservative as possible?)...Ice probably 0.5 to 0.75, though do not be shocked to see over an inch in areas especially with thunderstorms in the area. Snow, I'm sticking with the 6-12" for the metro as a good estimate right now with the amount of Sleet expected. Less sleet, we have the potential to be pushing the top of the scale. This will be a close one for the Metro. Some of us will be right on, the others will be way off. The boundary between frz rain/sleet/snow is going to be so close, it would be shocking to see the North Metro have a ton of snow and South Metro a lot of freezing rain.

[MikeOKC]

I'll start putting them up at JPGs. :-P

That part of town, taking into consideration the 18Z NAM which still has a significant amount of precip falling (oknacreous, trying to go as conservative as possible?)...Ice probably 0.5 to 0.75, though do not be shocked to see over an inch in areas especially with thunderstorms in the area. Snow, I'm sticking with the 6-12" for the metro as a good estimate right now with the amount of Sleet expected. Less sleet, we have the potential to be pushing the top of the scale. This will be a close one for the Metro. Some of us will be right on, the others will be way off. The boundary between frz rain/sleet/snow is going to be so close, it would be shocking to see the North Metro have a ton of snow and South Metro a lot of freezing rain.

Venture, Do you have a Twitter feed? I'd subscribe sooo fast! Putting all your stuff along with your cohorts with a hashtag of say #OKWX would be awesome.

[oknacreous]

Venture, I'm using the NAM forecast soundings which indicate a warm nose persisting up around 750 mb until at least late evening on Thursday. It's right on the melting line for several hours, so your prediction about a sharp gradient in snow totals across OKC is very plausible. This strongly reminds me of an event a couple of years ago where 10-15" of snow was predicted for OKC and the sounding was "oh so close" but the nose of warm air advection aloft won out in the end and we ended up with 3" of sleet and very little snow.

[venture]

@Mike - I have venturewx (venturewx) on Twitter setup. Going to try to work in some more things through anvilcrawlers.com to try to have a more focused location to find any information. Something we really didn't have for the Blizzard.

@oknacreous - Okay, we are both looking at the same thing then. Yeah I agree that this is very similar to that event from a few years back. Hopefully things get a bit more clear later this evening with the next set of runs.

[westsidesooner]

Thanks V....

I know these things can be really difficult. esp. this far out. And I know how much difference a few miles can make. We had a crippling icestorm (can't rmember if it was the 2001 or 2002 storm on the west side of OKC while the east side and Norman got off very lightly. To this day that one storm did the most damage to our property (more than even the 2007 storm....maybe because all the trees were already trashed) and we were without power for over a week. I appreciate the updates.....looking forward to the live blog....least til we lose power. :-( Starting to think I'm going to miss the old battery operated tv's...

[venture]

18Z GFS has gone colder it appears. Ugh.

[Thunder]

So I should panic right now. No power = Dead fish. My heat comes from 2 portable electric heaters. :-(

[Bostonfan]

Guys at stormtrack say there is a dry slot showing up. Any chance that can move in keep us from ice? Also Venture, you say it has become colder, would that suggest more snow than ice?

[adaniel]

18Z GFS has gone colder it appears. Ugh.

Does this enhance the probability of an icing event?

Also, I'm really curious as to what data these news stations are using as they are all over the place right now. KFOR is prediciting hardly any ice but 6-12 inches of snow, KWTV is showing a dusting of snow but a "cataclysmic" amount of ice, KOCO is in between the two but leaning towards more snow now.

My secretary watched Jeff Castles on her computer at lunch today as was downright startled.

EDIT: My cousin who is a night stocker at Wal Mart tells me they are already bracing for extra shipments of ice melt, shovels, etc. So no fighting and panicing tonight at the store people!

[Thunder]

Guys at stormtrack say there is a dry slot showing up. Any chance that can move in keep us from ice? Also Venture, you say it has become colder, would that suggest more snow than ice?

Do...not...say...the...two...words.

[Bostonfan]

Do...not...say...the...two...words.

Yeah, I hear ya. If there was no mention of an ice storm, I wouldn't mind the foot of snow. But........... I would take a dry slot any day over an ice storm. Ice storms are terrible, I don't wish them on any town/city.

[Dustin]

OMG!! Is anyone watching channel 4 news right now? Mike Morgan is hilariously over-dramatic!! I know this storm looks like it'll be a doozy, but mike just makes it seem like its the end of the world!

[venture]

Colder upper air temps would push us more to a sleet or snow event and away from Freezing Rain. Which I think most of us would prefer. LOL

The dry slot...couple things that show it well from the NAM 18Z that the guy on StormTrack was talking about:

http://grib2.com/nam/CONUS_NAM218_ATMOS_BRF_57HR.png
http://grib2.com/nam/CONUS_NAM218_ATMOS_BRF_60HR.png

Dry slots typically well stop most of the significant precip for a time (depending on wrap around) and you'll normally see light freezing rain or freezing drizzle then. It doesn't look like the dry slot will get north of I-44 at this time, but this goes back to what was said early. We can end up seeing a tight gradient in precip amounts just across the Metro.

[OKCMallen]

WTF is a dry slot!?

[venture]

WTF is a dry slot!?

It is when the storm starts to wrap in drier air on the back side. It'll move up into the circulation and start to cut the precip off in the areas it moves over, and eventually start to weaken the storm if it gets pulled in far enough.

[OKCMallen]

Gotcha.

We're all amateur meteorologist in the 405.

[woodyrr]

Does anyone know if the Norman NWS office (or any one else) has a link to a Sperry-Piltz ice forecast map for central Oklahoma like this one for northeastern Oklahoma from NWS Tulsa?

Sperry Piltz Utility Ice Damage Index

[oknacreous]

00Z model runs are basically status-quo. NAM is still warmer aloft so more ice and less snow (in general). GFS gets cooler faster and throws OKC over to snow early enough to get quite a lot. The million dollar question is whether 1) the difference lies in the fact that the NAM's vertical and horizontal resolution is better so it is able to depict the nuances of the thermodynamic structure of the system, or 2) the GFS is simply depicting something different. Based on the SREF output it's probably a combination of both.

I should have mentioned earlier I was being Norman-centric in my forecast so I'll be more generic for all of central OK here. Best chance of significant icing (3/4 to 1") and power problems is in the band from Lawton/Wichita Falls and Duncan to Purcell/Pauls Valley to Henryetta. Best chance for significant snow is in the band from Cheyenne to Enid and Ponca City with a foot of snow possible (and near-blizzard conditions). In between I still think the dominant precip type will end up being sleet, but with a significant gradient in snow totals across OKC - 1 to 2" southeast of Norman and 5 to 7" up around Piedmont. Things start going downhill rapidly midday Thursday.

[venture]

00Z Model runs for both NAM and GFS are continuing to push for more a freezing rain and sleet even for the metro. To pin point out close this is going to be.

Kingfisher: Freezing Rain to Sleet @ Noon to Snow/Sleet @ 3PM to Snow @ 6PM Thur.
Oklahoma City: Freezing Rain to Sleet @ 6PM to Sleet/Snow @ 9PM to Snow @ 3AM Fri.
Norman: Freezing Rain to Sleet @ 12 AM to Snow/Sleet @ 3AM to Snow @ 6AM Fri.
Pauls Valley: Rain to Freezing Rain @ 9PM to Sleet @ 6AM to Snow @ 12PM Fri.

I'll work on another amount forecast tomorrow after the next couple runs.

Best suggestions now, get your running around that you need done for food/water in case power goes out. For sidewalks and driveway...salt them down when temp falls. The brine solution will help keep it clear until the sleet/snow start. Then just be sure to shovel it off before you drive over the snow/sleet pack.

[westsidesooner]

Does anyone know if the Norman NWS office (or any one else) has a link to a Sperry-Piltz ice forecast map for central Oklahoma like this one for northeastern Oklahoma from NWS Tulsa?

Sperry Piltz Utility Ice Damage Index

I wish OUN would add that feature as well....for what its worth.

It'll also be interesting to see what kind of warnings OUN goes with tomorrow. Will it be a blanket Winter Storm warning for the entire area....or WSW north of I-40 and Ice storm warning to the south? I'm guessing blanket Winter Storm to start out with.

[venture]

According to 6Z NAM, OKC timeline looks about right, Norman is slowing down a bit to where they may be a longer period of freezing rain and/or sleet.

[sacolton]

Watched Channel 4 last night. Very interesting insight from Mike Morgan.

Kevin Ogle: Here's Mike Morgan with the latest on the winter storm. Mike?

Mike Morgan: (screaming) AHHHHHHHHHHH! AHHHHHHHHHH! AHHHHHHHHHHHH!

Kevin Ogle: Thanks, Mike. In other news ...

[Thunder]

Watched Channel 4 last night. Very interesting insight from Mike Morgan.

Kevin Ogle: Here's Mike Morgan with the latest on the winter storm. Mike?

Mike Morgan: (screaming) AHHHHHHHHHHH! AHHHHHHHHHH! AHHHHHHHHHHHH!

Kevin Ogle: Thanks, Mike. In other news ...

Mike wasn't that scary. If you want scary, read what Jed had said that someone posted.

David have his forecast out this morning for central calling for 1-3" ice with 5-10" snow.

wss, the NWS had already issued Winter Storm Warning for the most part of the state. We are in grave danger!