Southern Plains winter wx thread (2008-2009)

[Extremeweatherguy]

Norman, OK AFD....

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORMAN OK
508 AM CST SUN DEC 14 2008

.DISCUSSION...
VERY STRONG ARCTIC BOUNDARY POSITION WELL AHEAD OF MODEL GUIDANCE
THIS MORNING. CURRENT TRENDS WILL BRING IT INTO FAR NORTHWEST
OKLAHOMA BETWEEN 12Z AND 14Z...INTO CENTRAL PORTIONS OF OKLAHOMA
TOWARD 18Z AND THROUGH THE REST OUR FORECAST AREA BY 00Z. GRIDS
ADJUSTED ACCORDINGLY. ALTHOUGH MODELS DO NOT SUPPORT WIND
ADVISORY WIND SPEEDS DIRECTLY /WITH PROGD WINDS IN LOWER LEVELS/
...STRONG PRESSURE RISES CURRENTLY SEEN AND EXPECTED LATER TODAY
BEHIND FRONT EXPECTED TO HELP SUPPORT STRONG ACCELERATIONS AND
ALLOW US TO ISSUE A WIND ADVISORY FOR POST-FRONTAL WINDS.

GFS CONTINUES TO ERODE ARCTIC AIRMASS TOO QUICKLY TUESDAY INTO
WEDNESDAY. IN ADDITION..WE ARE BUYING INTO NAM/ECMWF DEPICTION OF
REINFORCING SHOT OF COLD AIR TUESDAY NIGHT AND WEDNESDAY. THIS
KEEPS OUT FORECAST NUMBERS ANYWHERE FROM 20 TO 40 DEGREES BELOW
GFS GUIDANCE NUMBERS. GIVEN UPSTREAM CONDITIONS...WE MAY STILL BE
TOO WARM. LATE WEDNESDAY INTO THURSDAY...APPEARS THAT THERE WILL
BE SOME ERODING OF AIRMASS...BUT BELIEVE ECMWF AND TO A LESSER
EXTENT...THE GFS TOO AGGRESSIVE WITH ARCTIC AIR REMOVAL. COULD SEE
A SIGNIFICANT TEMPERATURE CONTRAST ACROSS OUR FORECAST AREA...WITH
20S/30S ACROSS NORTHEAST SECTIONS AND 60S+ FAR SOUTHWEST. WE WILL
STAY ON THE COLDER SIDE OF THIS WITH APPARENT QUALITY OF AIR AND
REINFORCEMENTS.

AS FAR AS PRECIP...IT STILL APPEARS THAT WE COULD ESCAPE A MAJOR
ICE EVENT...BUT SOME CONCERN DOES EXIST DURING PROGD AIRMASS
TRANSITIONS WHEN MID-LEVEL WAVE EJECTS AND INCREASED WAA OCCUR
TOWARD THURSDAY. REGARDLESS...APPEARS THAT PERIODIC EPISODES OF
LIGHT FREEZING OR FROZEN PRECIP IS LIKELY...WHICH WILL MAINLY HAVE
IMPACTS ON TRAVEL.

ALL MODELS...IF YOU CAN BELIEVE THEM THAT FAR OUT...HAVE ANOTHER
MAJOR BLAST OF COLD AIR FRIDAY AND SATURDAY. GIVEN EXPECTED
PATTERN...WE WILL GO WITH ECMWF SOLUTION AND DROP TEMPS AGAIN
TOWARD NEXT WEEKEND.

[srainhoutx]

Interesting week ahead. Stay warm Extremeweatherguy.

[wxman22]

Latest 12z GFS is still showing interesting weather next weekend...

[Extremeweatherguy]

What's funny is that the models still have NO clue about what is going on. The 12z runs still all think the front will be arriving later this evening, with the cold air then conveniently eroding by Tuesday. lol.

[Extremeweatherguy]

High pressure now up to 1058mb in NW Canada...

http://www.hpc.ncep.noaa.gov/sfc/satsfcnps.gif

This is 6mb stronger than both the 12z NAM and 12z GFS initialized it as being.

[PTPatrick]

Just an FYI...Denver is still dropping. Was -1 3 hours ago, now its -3. We are supposed to be "warming" up to single digits, but so far it aint happening. Currently we are sitting AT our projected low for tonight...with the sun peaking through. Feel that forecast is already busted and suspect most of Oklahoma's forecast will be a bust as well.

[Extremeweatherguy]

Just an FYI...Denver is still dropping. Was -1 3 hours ago, now its -3. We are supposed to be "warming" up to single digits, but so far it aint happening. Currently we are sitting AT our projected low for tonight...with the sun peaking through. Feel that forecast is already busted and suspect most of Oklahoma's forecast will be a bust as well.

Yeah, I noticed that -3F in Denver. Pretty impressive to see you guys continuing to drop through the morning like this. Denver is really going to struggle to get anywhere close to the forecasted high of 9F today, and I wouldn't be surprised if the airport stays near 0F through the entire afternoon. This is turning out to be a pretty impressive arctic airmass!

[Extremeweatherguy]

According to the Oklahoma Mesonet, Red Rock, OK just fell from 67F to 57F in 5 minutes! That is very impressive and equates to a drop of 2F per minute.

[Extremeweatherguy]

El Reno, OK (on the west side of OKC) just fell from 69F to 55F in 10 minutes!

BTW - There is a 60 degree temperature gradient across the state right now! SW parts of the state are in the mid/upper 70s while the panhandle is in the mid/upper teens. Talk about impressive!

[BlueIce]

Reminds me of an event in November 2006, it was near 80 in SE Oklahoma and it was in the upper 20's in the panhandle

[Extremeweatherguy]

The front is pushing through NW Oklahoma City pretty quickly right now...

http://www.wunderground.com/radar/radbl ... rainsnow=0

It is only a matter of time before those in south OKC, Moore and Norman see their days ruined by this incoming airmass. The rare 72-degree temperatures currently being experienced in those areas will not last too much longer, so get out and enjoy it while you can!

[Extremeweatherguy]

Reminds me of an event in November 2006, it was near 80 in SE Oklahoma and it was in the upper 20's in the panhandle

Yes, that was a very exciting event. I lived in Houston at the time, but the experience was almost as impressive down there. We went from 70s that morning to mid 30s (and windy) by the evening.

[iorange55]

LOL WOW! The models sure did good predicting this one, it's now coming in around 8 or 9 PM! In the dallas area. I can't wait :]

[BlueIce]

The front is pushing through NW Oklahoma City pretty quickly right now...

http://www.wunderground.com/radar/radbl ... rainsnow=0

It is only a matter of time before those in south OKC, Moore and Norman see their days ruined by this incoming airmass. The rare 72-degree temperatures currently being experienced in those areas will not last too much longer, so get out and enjoy it while you can!

I am currently experiencing the wind shift, went out and looked at the weather vain, its trying to shift to the north as I type.

Current temp is 74 at my place, around the I-40 & I-240 interchange, we will see how fast it drops in the next few hours.

Update at 3:20, Temps down to 47. Wind is N @ 25 G 30

[Extremeweatherguy]

The front is through! Temperatures are currently falling through the 50s quickly with a north wind.

[southerngale]

When should it reach SE TX, assuming it will? NWS forecasts a low of 63° tonight and a high of 76°F for tomorrow. But I guess that is what is supposed to drop our temps to a "cool" 48°F tomorrow night and a high of 61°F on Tuesday. I guess it isn't supposed to be as impressive down here as it is up there, or are they just way off, I wonder. It's pretty warm today (currently 69°F, but a predicted high of 76°F), and the forecast for the next few days is also on the warm side, considering it's the middle of December. Not very Arctic-like.

It's quite windy out there, though. We have a wind advisory.

[iorange55]

Dallas Noaa Discussion seems to think the front will already be lifting back out of the area by Tuesday night. I hope that is not the case.

ISENTROPIC LIFT WILL INCREASE ACROSS THE REGION MONDAY NIGHT AND
TUESDAY AS SURFACE LOW PRESSURE DEEPENS ACROSS THE ROCKY MOUNTAIN
WEST IN RESPONSE TO A DEVELOPING WEST COAST UPPER TROUGH. THE NORTHWEST
ZONES WILL BE AT OR BELOW FREEZING MONDAY NIGHT/TUESDAY MORNING SO
LIGHT FREEZING RAIN WILL BE POSSIBLE. TEMPERATURES SHOULD WARM
ABOVE FREEZING AREA WIDE TUESDAY AFTERNOON. ALL MODELS SEEM TO
AGREE THAT THIS BATCH OF COLD AIR WILL BE QUICKLY REPLACED BEGINNING
TUESDAY NIGHT AS SOUTHERLY WINDS RETURN TO THE REGION. BOTH THE
ECMWF AND GFS HAVE BACKED OFF ON BRINGING ANOTHER COLD FRONT ACROSS
THE RED RIVER WEDNESDAY. EVEN THE 84 HOUR NAM SOLUTION SHOWS THE
FRONT LAYING UP NORTH OF THE RIVER. WILL FOLLOW THIS GENERAL
SCENARIO BUT WILL STILL UNDERCUT MOS NUMBERS AS THE EXCESSIVE
WARMUP THURSDAY AND FRIDAY APPEARS UNREALISTIC.

[HarlequinBoy]

The Mid South is awaiting the front and ice storm for the I-40 corridor northward.

[Extremeweatherguy]

It really cooled off in a hurry here. We are already down into the upper 30s/lower 40s with a north wind. Brrr. It is definitely a far cry from the 72-degree weather we were experiencing just 2 hours ago.

[Extremeweatherguy]

When should it reach SE TX, assuming it will? NWS forecasts a low of 63° tonight and a high of 76°F for tomorrow. But I guess that is what is supposed to drop our temps to a "cool" 48°F tomorrow night and a high of 61°F on Tuesday. I guess it isn't supposed to be as impressive down here as it is up there, or are they just way off, I wonder. It's pretty warm today (currently 69°F, but a predicted high of 76°F), and the forecast for the next few days is also on the warm side, considering it's the middle of December. Not very Arctic-like.

It's quite windy out there, though. We have a wind advisory.

I think they are probably just way off. Based on posts by wxman57 and Jeff that I saw in another forum, it looks like they both expect a chilly, wet scenario for SE Texas through midweek. I even heard them mention highs possibly in the 40s for you guys, which is pretty chilly.