Wow. When was the last time this happened this far north and this late in the year?

Umm the October 26 2010 High Risk for a derecho. Nov 15 2005 High Risk for a tornado outbreak but hat was Mid-Miss valley. So looking through everything, this is the latest high risk that is so far north. There have been some in Dec/Jan but in the traditional Dixie Alley which has their tornado season during Winter.

If you have family/friends up there...give them a heads up. Real deal today.



Do this^ ASAP.
This is potentially very serious !!!!!!!!

What are the chances of snow in Grove, OK the week of Thanksgiving? We are coming up from Florida and would LOVE to see some snow.

http://www.spc.noaa.gov/products/md/mcd2010.gif

NWS STORM PREDICTION CENTER NORMAN OK 0747 AM CST SUN NOV 17 2013

First PDS tornado watch is out for IL, WI, and MO. Here we go...

http://www.spc.noaa.gov/products/watch/ww0561_radar.gif

Quick side note, I know everything today has nothing to do with Oklahoma...but its a pretty big day and many of us have family/friends up there. Not to mention posters (Spartan) up in Ohio. :)

All too familiar images coming out of the areas back north...

https://pbs.twimg.com/media/BZTtbf7CMAAFUTr.jpg:large

Ugh :(

Sad. Where is that?

Washington, IL. Looks like classic EF-4 damage at least.

One for the history books for sure...

http://www.spc.noaa.gov/climo/reports/131117_rpts.gif

Of course, all of the news sources will be all over this tomorrow citing global warming as the cause. LOL

00Z GFS get us pretty white for Turkey week.

http://www.twisterdata.com/data/models/gfs/3/maps/2013/11/18/00/GFS_3_2013111800_F192_SNOWIN_SURFACE.png

http://www.twisterdata.com/data/models/gfs/3/maps/2013/11/18/00/GFS_3_2013111800_F300_SNOWIN_SURFACE.png

Wow, so there's a chance of snow! WOOHOO!!!

Chance of passing showers Wednesday into Thursday.

Chances go up pretty high Thursday into Friday with Friday looking like a real soaker. Cold air behind Low looks to be too slow to warrant any winter precip in main body of OK. Just a classic cold rain.


Next week is going to really depend on this first Low that comes through later this week. If it pulls down enough cold air and keeps it here, next week could be bread and milk warning worthy. A low comes out of the SW and kind of ramps up as it ejects over TX into OK. Right now I am siding with temps being too warm. But will keep updates coming.

The following week (first week of Dec) looks like a lot of fun, right now.

Chance of passing showers Wednesday into Thursday.

Chances go up pretty high Thursday into Friday with Friday looking like a real soaker. Cold air behind Low looks to be too slow to warrant any winter precip in main body of OK. Just a classic cold rain.



NOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO.....I need at least a tolerable Friday. Not a cold, driving rain. NOOO!!!

Pleeeeeeze?? C'mon, anon, you and Venture can hook up some magic and flip that Friday forecast on its head, cantchya? :)

Just have some outdoor/evening camera work that night and cold+rain is a LOUSY combo....

Check out these crazy images from Washington, IL

https://scontent-b-dfw.xx.fbcdn.net/hphotos-frc3/1469749_533618040065569_1444762324_n.jpg

https://scontent-b-dfw.xx.fbcdn.net/hphotos-ash4/1459766_10152001597785861_323218438_n.jpg

It's a wonder more people didn't get killed.

Check out these crazy images from Washington, IL
https://scontent-b-dfw.xx.fbcdn.net/hphotos-frc3/1469749_533618040065569_1444762324_n.jpg

Do tornados always spin counter-clockwise? Is it like the toilet water phenomenon?

Check out these crazy images from Washington, IL



That's amazing

Do tornados always spin counter-clockwise? Is it like the toilet water phenomenon?

Not always, we do have anti-cyclonic tornadoes from time to time as well.

12Z model data is half in for the end of this week. Upgrade to Bread and Milk Warning might be forth coming. :)

Going to start throwing out some quick observations of the 12Z NAM...Everyone knows the drill on run to run consistency and all that jazz, so yeah.

Most important part on this...the freezing line.

6PM Thursday - NW Panhandle
12AM Friday - It'll run from Alva to Taloga to Cheyenne.
6AM Friday - Newkirk to Norman to Lawton to Altus.

For the rest of the day on Friday it'll sit roughly in the same area from Pawnee to Stillwater to Shawnee to Pauls Valley to Waurika.

Now the precip forecast for the Metro...

6PM Thur to 3AM Fri - Scattered showers. Light rain.
3AM Fri to 6AM - Light to moderate rain, up to a 0.25".
9AM Fri - Mostly dry.
12PM Fri - Light to moderate precip, up to a 0.10" developing.
3PM Fri - Moderate rain over the entire metro area, up to 0.35" of liquid equiv.
6PM Fri - Moderate to heavy precip, up to 0.5" of liquid equiv.

Forecast soundings are not good (see below). Profile for the entire time the precip starts heavily favors freezing rain, not sleet or snow. This would provide a solution with well over the quarter/half inch criteria for an Ice Storm Warning.

http://climate.cod.edu/data/forecast/sndgs/NAM_12_081_35.39;-97.43.gif
http://wxcaster4.com/nam/CONUS1_NAM212_SFC_ACCUM-SLEET_84HR.gif

http://wxcaster4.com/nam/CONUS1_NAM212_SFC_ACCUM-FZRN_84HR.gif

I think we need to issue a "bread & milk" watch from Saturday through Monday.

Do tornados always spin counter-clockwise? Is it like the toilet water phenomenon?

According to my meteorology professor 2% of all tornadoes in the northern hemisphere rotate clock wise.

I had a typed up synoposis of the signs of potential ice storm. But deleted it this morning and decided to wait.

But since venture pressed the button. Might as well echo his post.

Right now I am not buying the solution for ice. I think models are going too cold with the system after the initial precip from Thursday. And the precip that we get Friday eve as the low pushes out will be occurring before the cold air gets its main push SE. So for me, I am sticking with cold rain main body of OK. But I have not removed my finger from the Bread and Milk Warning button.

I had a typed up synoposis of the signs of potential ice storm. But deleted it this morning and decided to wait.

But since venture pressed the button. Might as well echo his post.

Right now I am not buying the solution for ice. I think models are going too cold with the system after the initial precip from Thursday. And the precip that we get Friday eve as the low pushes out will be occurring before the cold air gets its main push SE. So for me, I am sticking with cold rain main body of OK. But I have not removed my finger from the Bread and Milk Warning button.

Indeed. The one hang up on this, so far this morning anyways, is we are just now getting into the NAM's forecasting window. So there isn't a lot of previous runs to base anything off of. Over the last 4 runs though it keeps speeding up the arrival of the cold air. 18Z yesterday had the 32° line up in NW KS. 00Z last night it was in the OK Panhandle. 06Z just past the first few counties in extreme NW OK. Now the 12Z has it passed a few more counties. GFS is slowly trickling in now so we'll see what that says and also the 12Z Euro run.

Definitely not a locked in solution yet, but I figured the Payne and Morgan hype machines will be going by this evening...so might as well get out ahead of it. :)

What do you see for people up in NE OK? I figured us up here in Tulsa it will take awhile for us to switch over.

NAM is holding out switching over up in TUL. 00Z Euro has it going below freezing by mid afternoon up there. 12Z GFS should be in for that time period in about 10 minutes.

Good of time as any to refresh everyone on the Winter definitions per the NWS Norman office on how they define them here (these vary as you go further north in the US).

Winter Wx Advisory (not travelers advisory!!!) - Snow up to 3", Sleet/Freezing Rain that impact driving and walking.

Winter Storm - Snow over 4" in 12 hours, over 6" in 24 hours; more than 0.5" of sleet

Ice Storm - Over 0.25" of freezing rain

Blizzard - Winds over 35 mph for 3 hours, enough snow to blow/drift

12Z GFS is in and it brings in the freezing line down to the OKC area by 9AM, but then retreats it all the way back into NW KS by Noon and Nebraska by 3PM. It then surges back down south of I-40 by Saturday morning. This is mostly consistent with the last several runs on GFS.

So essentially nothing new at this point with models not agreeing.

Should note that last night the HPC was tossing out the GFS solutions for being out of line with the consensus of most models, including NAM and ECMWF. I'm with Anon though...this is going to tough to call since we've seen it many times before where models are aggressive with the arrival of cold air and it doesn't get here in time.

Wow - this could get pretty dicey!

Aside from all the obvious problems for general travel and commerce on Friday, there's an extra factor going on here with high schools across the state involved in state playoffs on Friday. That's not just teams, but bands, support people, parents, officials, going all over the state. Just have to see how it all plays out, I s'pose.

12Z Euro/ECMWF is in and it is roughly between the NAM and GFS now with surface temps on Friday, keeping us mostly above freezing through Saturday. Maybe some light snow Sunday over Western and Central OK.

I get out of college late on Fridays, I hope it doesn't do anything because I don't wanna be driving in that weather

As we are getting closer to the weather event/s, I get a strong feeling that the models are not handling this shallow arctic air mass very well. If I recall right, shallow arctic air masses move down fairly quickly, but it takes awhile for them to move east. Any mets on here that could answer this question for me-is this low pressure center going to be a lakes cutter or head due east into the Southeast part of the country? The other day, it appeared it would be a lakes cutter, now it's going due east...seems a little crazy. What do you think?

Really quick...the 18Z NAM is pretty much unchanged, the 18Z GFS is unchanged...so the stand off continues there. With the Euro being closer to the GFS now, that looks like the solution to lean towards. We'll see how things continue to evolve.

Now to Amber's question. Is it bad that I've never heard of the term "Lakes Cutter" before...and I grew up in the Great Lakes? LOL Alberta Clippers, Double-Barrel lows, etc...those were commonly used. :) So after looking it up I now have an idea what you are discussing. It does seem the main storm is going to stay north, based on GFS, and then intensify as it gets north of the Lakes. We will have a secondary storm system down here, but looks like that gets stretched out and absorbed north.

Longer range I'm really interested on the low moving through Texas in a week. Looks like this is going to make the classic curve up the coast and bring a major Nor'easter to the New England and the Mid Atlantic. It looks like it'll make the turn over the Appalachians - setting up the double barrel setup with the energy transferring east to a new coastal low. For those traveling for the holidays...keep it in mind.

On the subject of when the cold air arrives, there seems to be quite a bit of disagreement among the different SREF members, with about 18 hours total of range between the earliest and latest members.

NCEP SREF Plume Viewer (http://www.spc.noaa.gov/exper/sref/fplumes/index.php?YMD=20131119&RT=15&PRM=3hrly-TMP&SID=OUN&INC=ALL&NNC=&max=&min=&mZOOM=4&mLAT=37.77478874678&mLON=-96.042896875&mTYP=roadmap)

Thursday will be dry?

Thursday will be dry?

Doesn't appear so at this time. Also 00Z NAM maintains its previous thinking.

Quite a bit less QPF, however.


Doesn't appear so at this time. Also 00Z NAM maintains its previous thinking.

Quite a bit less QPF, however.

Gawd...picky picky. :-P

Though if it verifies Central OK is still looking at...half inch to around 0.85". Still significant if it is all frozen or freezing. :)

The 12z Canadian Model paints a colder scenario for Sunday-Tuesday as the 2nd part of this system starts to move out. I can't post a pic right now but between hours 132-144..most of OK except far SE is in a snow/wintry mix. The GFS also is showing a similar idea when the storm finally starts to push its way east on Sunday/Monday. I think that's our best chance for snow in the central to NE part of the state. Any thought? Haven't seen the Euro yet.

06Z NAM still the same in respect to temps. Precip amounts are a bit lower, but still there. 06Z GFS seems to be getting slightly more aggressive in the push of colder air.

NWS Norman discussing that Winter Wx Advisories are probably going to be likely for the area along and north of I-44.

06Z NAM still the same in respect to temps. Precip amounts are a bit lower, but still there. 06Z GFS seems to be getting slightly more aggressive in the push of colder air.

NWS Norman discussing that Winter Wx Advisories are probably going to be likely for the area along and north of I-44.

For what time period, ven?

I still can't buy the icestorm solution yet. But we are about 60 hours from event start and it is going to be a close call.

One thing I am noticing is the actual low ejection out of the SW is slowly being moved north with the runs. This could be extremely fickle on temperature and snow amounts Sunday into Monday. If the low tracks a little further north into N TX and S OK, when it taps into the moisture pot over TX, it will start ramping up and someone is going to get dumped on by cold rain or heavy wet snow. The snow solution would be much of OK. Again this is based on the trend to eject the low further north. The most likely track will be based on where this initial moisture stream sets up over TX/OK in the coming days. It could be a sharp gradient of heavy snow to zero snow right over the state. Or of course, it could just be rain in the S and SE part of OK.


Bread and Milk Warning may be issued by tomorrow evening.

Just to show you folks what the poster above is talking about. The Canadian model is wanting to eject the low further north than what the GFS is showing. This is at hour 132...you can clearly see the freezing line is in Texas aside from the extreme SE OK. I don't know about you, but I REALLY like snow:)5081

SPECIAL WEATHER STATEMENT:

Updated: Wed Nov-20-13 06:31am CST
Effective: Wed Nov-20-13 06:31am CST
Expires: Thu Nov-21-13 06:45am CST
Severity: Minor
Urgency: Expected
Certainty: Observed
Status: Actual
Type: Alert
Category: Met

Areas affected: Alfalfa; Beckham; Blaine; Caddo; Canadian; Cleveland; Comanche; Custer; Dewey; Ellis; Garfield; Grady; Grant; Greer; Harmon; Harper; Jackson; Kay; Kingfisher; Kiowa; Lincoln; Logan; Major; McClain; Noble; Oklahoma; Payne; Pottawatomie; Roger Mills; Tillman; Was hita; Woods; Woodward

Message summary: ...much colder temperatures and wintry precipitation expected across portions of oklahoma and western north texas this weekend...

A strong cold front will move into northwestern oklahoma thursday afternoon...and then quickly push south across central oklahoma and western north texas thursday night. Freezing rain...and perhaps some sleet...will be possible behind this front beginning late thursday night mainly along and north of the interstate 44 corridor. It is difficult to determine how much ice accumulation will occur through early saturday morning...but at least some light accumulations of less than one quarter of an inch appear very likely on elevated surfaces such as bridges...overpasses...trees and powerlines. In addition to freezing rain and drizzle...wind chills in the low teens are expected behind the front friday and saturday morning mainly north and west of interstate 44. Be sure to monitor the forecast over the next couple of days. You can stay up to date with the latest forecast by visiting our website at NOAA National Weather Service (http://www.weather.gov/oun...listening) to noaa weather radio...or by following national weather service norman oklahoma on facebook and twitter.

Winter Wx Advisories are out for much of Central and SW Kansas now. We'll probably see OUN pull the trigger by tomorrow morning.

Quick heads up...

Severe weather chances tomorrow...mainly hail risk. Winter weather then moves in after and remains through the weekend on an off.

Chat room will be rolling to cover FLURRYGEDDON 2013. ;)

18Z NAM on schedule with the cold air timetable it previous had. 18Z GFS has sped up again to match the NAM a bit more.

Precip amounts are lower overall however.

18Z Forecasts...

Sleet Accumulation
http://wxcaster4.com/nam/CONUS1_MESO-NAM212_SFC_ACCUM-SLEET_84HR.gif

Freezing Rain/Ice Accumulation

http://wxcaster4.com/nam/CONUS1_MESO-NAM212_SFC_ACCUM-FZRN_84HR.gif

A hint of what NAM is thinking for Saturday...

http://wxcaster4.com/nam/CONUS1_MESO-ETA212_SFC_12HRACCUMSNOW_84HR.gif

From the new OUN AFD...

AT THIS TIME...LOOKS TO BE WINTER WEATHER ADVISORY LEVELS OF
IMPACTS WITH TOTAL ICE ACCUMULATIONS UNDER 0.25 INCH MAINLY ALONG
AND NORTHWEST OF I-44...INCLUDING THE OKLAHOMA CITY AND LAWTON
AREAS. THE WORST CASE SCENARIO WOULD BE THAT THE COLD AIR ARRIVES
QUICKER THAN CURRENTLY FORECAST AND PRODUCE OVER 0.25 INCH OF ICE
SOMEWHERE WHERE THE COLD AIR AND DEEPEST MOISTURE OVERLAP.
CONFIDENCE THAT A SIGNIFICANT ICE STORM WILL OCCUR REMAINS
LOW...ESPECIALLY AS CLIMATOLOGY IS NOT FAVORABLE FOR THIS TO OCCUR
IN OKLAHOMA OR WESTERN NORTH TEXAS IN MID TO LATE NOVEMBER.

THE BIGGEST IMPACTS FROM POSSIBLE FREEZING RAIN WOULD OCCUR LATE
THURSDAY NIGHT INTO FRIDAY...ESPECIALLY FRIDAY MORNING WITH
SLICK BRIDGES AND OVERPASSES AS WELL AS SOME MINOR ICE
ACCUMULATIONS ON TREES AND POWERLINES ANYWHERE NORTHWEST OF A
SEYMOUR TO WICHITA FALLS TO LAWTON TO NORMAN TO CHANDLER LINE.

Norman's first precip prediction...

http://www.srh.noaa.gov/images/fxc/oun/graphicast/image1.jpg

What are the ground temps? Aside from bridges and overpasses, are we looking at major problems on the roads with the way things are with 0.25 inch of freezing rain, or are we looking at it melting?

Winter Ball Friday night, all state jazz auditions Saturday morning to get to ;) My car gets blown around in the wind; I've not really tested it on ice. It's so tiny and light I'm a little scared of slick roads.

Pretty warm still...

http://www.mesonet.org/data/public/mesonet/maps/realtime/current.TS05.grad.png

Hey Venture,

Lots of folks headed up to Tulsa for this weekend's Route 66 Marathon on Sunday. What to turnpike conditions look like, as well as temps/precip in T-town for race day (Sunday morning).

00Z NAM is in...still the same. Precip is mostly going to be before noon except for some freezing drizzle later in the day. I still feel Winter Wx Adv go up with the update early tomorrow morning. Questions still remain on how deep the cold air will be to give us freezing rain or sleet. Sleet obviously would cool surface temps down faster and allow ice to accumulate, but freezing rain giving us the glaze makes it more hazardous to elevated surfaces (roads and power lines).

The new precip forecasts...

Freezing Rain Accumulation
http://wxcaster4.com/nam/CONUS1_NAM212_SFC_ACCUM-FZRN_48HR.gif

Sleet Accumulations
http://wxcaster4.com/nam/CONUS1_NAM212_SFC_ACCUM-SLEET_48HR.gif

Snowfall

http://wxcaster4.com/nam/CONUS1_ETA212_SFC_12HRACCUMSNOW_48HR.gif

Hey Venture,

Lots of folks headed up to Tulsa for this weekend's Route 66 Marathon on Sunday. What to turnpike conditions look like, as well as temps/precip in T-town for race day (Sunday morning).

Looks like it should be dry with temps in the teens and 20s. There could be some overnight snow/sleet in Central OK on Saturday that could make the turnpike, until about Stroud, a little slick here and there. Ideally the ground temps will stay up and it won't be an issue.

Latest update from Norman...

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORMAN OK
953 PM CST WED NOV 20 2013


.UPDATE...
MODIFIED DEWPOINTS AND TEMPS A LITTLE FOR OVERNIGHT PERIOD.
MOST OF ANY SHOWER AND STORM DEVELOPMENT WILL LIKELY BE OVER FAR
NORTHERN AND NORTHEAST OKLAHOMA OVERNIGHT BUT WILL NOT REMOVE THE
LOW POPS ACROSS WESTERN/SOUTHWEST OKLAHOMA WITH IMPACT OF S/WV AND
SPEED MAX JUST NOW EXITING NEW MEXICO.


00Z WRF MODEL...WHICH HAS BEEN SIGNIFICANT OUTLIER TO OTHER MODEL
SUITES...LESS AGGRESSIVE WITH SIGNIFICANT ICE POTENTIAL. DPROG/DT
ON LOCATION/INTENSITY OF HEAVIEST PRECIP BANDS INDICATES FARTHER
EAST AND SOUTH PLACEMENT OF QPF AFTER 12Z FRIDAY. NO SIGNIFICANT
CHANGES TO LATE THURSDAY THROUGH EARLY SATURDAY FORECAST AND WILL
LET MIDSHIFT PONDER NEW GFS/ECM/SREF RUNS BEFORE ADVISORIES ARE
ISSUED.

Can you speak in English above? I'm sorry I don't understand what the NWS is trying to say about the WRF is doing,lol. Sound like they need some sleep:)