Southern Plains winter wx thread (2009-2010)

[iorange55]

Even the usually conservative GFS MOS is starting to bite on next weeks possible event (especially for Oklahoma). Here is what the 00z MOS guidance is showing...

For OKC:

SUN
High - 43
Low - 29
Variable clouds with a 13% chance of precipitation (snow)

MON
High - 43
Low - 26
Variable clouds with a 19% chance of precipitation (rain/snow)

TUES
High - 38
Low - 28
Overcast with a 49% chance of precipitation (snow/sleet)

WED
High - 36
Low - 25
Overcast with a 44% chance of precipitation (snow)

For DFW:

SUN
High - 49
Low - 35
Partly cloudy with an 18% chance of precipitation (rain/snow/sleet)

MON
High - 54
Low - 38
Overcast with a 16% chance of precipitation (rain)

TUES
High - 54
Low - 38
Overcast with a 32% chance of precipitation (rain)

WED
High - 49
Low - 33
Overcast early then clearing with a 38% chance of precipitation (rain/sleet)

Unfortunately for you guys down in Dallas it still seems that the MOS guidance is way too conservative. It is likely going to be much colder for you guys than what it is showing. The trend is toward colder (and wetter) though, so things are definitely going in the right direction.

Thanks for laying it out, but I agree that it's probably way too conservative right now, I guess it could possibly stay like it is, but I just don't see how considering that the high is so strong, and since we've been seeing stronger cold fronts it seems like in a line now for the past few weeks. It also always seems like they don't predict the real cold till one or two days out. As evidence by the past few days.

[mysterymachinebl]

Here's what CBS 11 in Dallas is showing....

[Extremeweatherguy]

The 12z GFS is continuing with the cold and stormy look next week. Based on the precipitation amounts the model is spitting out, there would definitely be potential for some areas of the southern plains to see significant accumulations of ice, sleet and snow. It will all depend on how much cold air can get involved and how far south that cold air will push.

[iorange55]

The 12z GFS is continuing with the cold and stormy look next week.

lol this peak your interest?

[Extremeweatherguy]

The 12z GFS is continuing with the cold and stormy look next week.

lol this peak your interest?



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Oh, definitely. That would be amazing if it were to play out. This run is showing rain or a mix Tuesday morning transitioning to sleet by Tuesday evening transitioning to Snow Tuesday night into Wednesday for OKC. We would probably see a decent accumulation if it played out like this run is showing.

[msstateguy83]

THIS APPEARS NOW TO BE A MAJOR STORM SETTING UP FOR NEXT WEEK WITH EXTREEMLY COLD TEMPS
IAM GONNA GO OUT ON A LIMB AND SAY MON - THU MAIN BODY OF OKLAHOMA AND INTO NORTH CENTRAL TX
MIGHT NOT GET ABOVE THE FRZING MARK FOR MOST OF THAT TIME PEROID. I WOULD ALSO BE WILLING TO
BET ITS NOT GONNA BE ALL SNOW WE MIGHT HAVE SOME SNOW AND MORE SNOW THEN ICE IN AREAS BUT
YOUR LIKELY ALSO GOING TO BE LOOKING AT UP TO 1/2" OF ICE ON TOP OF THE SNOW IN AREAS... THIS
HAS TO BE FOLLOWED EXTREMELY CLOSELY IN COMING DAYS AS ITS SHOWING SOME TEETH AND COULD SERRIOUSLY
DISRUPT WORK,TRAVEL FOR A LARGE PORTION OF OK AND TX INTO EARLY, MID PART OF NEXT WEEK...

[Extremeweatherguy]

It's going to be a cold one in Oklahoma tonight...

[msstateguy83]

it looks like attm the regional nws offices oun, ft worth have decided to scale
back on next week for (due to what they believe per euro runs lack of moisture)
they had my area around wichita falls at 40% for tues night dropped down to 30%
oun forecast disc is yet to be posted but ft worth said they was goin with the euro
which has the front coming thru as mostly dry. anyone else have any thoughts on
this? the 18z run should be out shortly and i will be looking over it

[Extremeweatherguy]

it looks like attm the regional nws offices oun, ft worth have decided to scale
back on next week for (due to what they believe per euro runs lack of moisture)
they had my area around wichita falls at 40% for tues night dropped down to 30%
oun forecast disc is yet to be posted but ft worth said they was goin with the euro
which has the front coming thru as mostly dry. anyone else have any thoughts on
this? the 18z run should be out shortly and i will be looking over it

The Norman office, on the other hand, is siding more with the GFS. It will be interesting to see who is right in the end.

[Ntxw]

It seems like so far, the gfs has been a better model for precip and storm tracks (relatively so far) this year. The ecmwf has had a better hold on temperatures

[msstateguy83]

00z gfs is currently coming in iam fixing to look over it as soon as its complete and i will post
some thoughts

[msstateguy83]

iam using accuwx pro and its still loading, iam in the process of doin a couple other things
before bed time but if anyone has any input and has reviewed it already go for it and i will put my 2 cents in when i get to look at it all good.

[iorange55]

iam using accuwx pro and its still loading, iam in the process of doin a couple other things
before bed time but if anyone has any input and has reviewed it already go for it and i will put my 2 cents in when i get to look at it all good.

Showing the low, and precip going a little north Kansas looks to get a lot of it, but I suspect it will change I'm not really trusting what it has to say at the moment, it's bringing the cold air down further south, though. So we've got one thing we need, just need the precip further south. If the low does indeed go that far north then we would probably not see anything down in North Texas.

[zaqxsw75050]

Yeah... the latest run of GFS doesn't look good for us... Hope things will change as we get near that time frame.

[Extremeweatherguy]

The 00z GFS looks warmer, bringing the surface low pressure feature further north next week. Probably only a slight chance of snow on the back-edge of the system as it is moving out if this run is correct. We are still several days out though, so I expect the back and forth to continue. The further south the surface low moves, the better the chances are for ice and snow into OK/TX and the further north it moves, the lesser the chances. It's worth noting that this run still shows it getting very cold behind the low though, with a high temperature struggling to make it past freezing in OKC next Wednesday. So no matter what, the cold weather will definitely be getting a big boost next week.

[msstateguy83]

yea i just got all mine loaded and was not thrilled to see that far of a shove to the north of
the low and precip getting up there w/it however its just one run, it has been pretty consistent up until this change so time will tell....

[Extremeweatherguy]

One thing's for sure - - Regardless of what happens next week, it is definitely a COLD one tonight. My temperature here on the south side of OKC is already down to 22F and it is not even midnight yet.

[BlueIce]

One thing's for sure - - Regardless of what happens next week, it is definitely a COLD one tonight. My temperature here on the south side of OKC is already down to 22F and it is not even midnight yet.

23F here on the east side of the metro

[Extremeweatherguy]

The NWS in Norman is still thinking a big southern plains winter weather event is on the table for next week...

DISCUSSION...
STRONG UPPER RIDGE NOW BUILDING OVER EPAC/AK WILL KEEP US IN A COLD
PATTERN FOR THE NEXT WEEK. LONGWAVE TROF WILL BE MAINTAINED
DOWNSTREAM FROM CENTRAL CANADA INTO CENTRAL/W CONUS AS SYSTEM NOW
OVER BRITISH COLUMBIA DROPS S. BASED ON PROJECTED STRENGTH AND
AMPLITUDE OF THE EPAC RIDGE... ASSOCIATED COLD INTRUSIONS OVER THE
NEXT SEVERAL DAYS PROBABLY WILL BE DESERVING OF MORE RESPECT THAN
MOST OF THE MODELS ARE GIVING THEM. THUS WILL LEAN TOWARD COLD SIDE
ON FORECAST TEMPS AND MORE SOUTHERN TRACKS OF THE SURFACE WAVES
ASSOCIATED WITH DISTURBANCES COMING OUT OF THE CENTRAL/WESTERN TROF
SUNDAY AND TUESDAY. THIS LEADS TO A POTENTIALLY INTERESTING SCENARIO
FOR EARLY NEXT WEEK AS THE COLD AIR IS APT TO REMAIN MORE RESILIENT
THAN INDICATED BY THE MODELS. WILL MAINTAIN SOME LOW POPS AROUND
SUNDAY AND HIGHER POPS AROUND TUESDAY. ALTHOUGH THE LESS-AMPLIFIED
UPPER SYSTEM DEPICTED FOR TUESDAY ON THE LATEST ECMWF AND THE GFS
ENSEMBLE IS PREFERRED... THERE IS SOME POTENTIAL FOR A SIGNIFICANT
WINTER WX EVENT FOR AT LEAST NORTHERN PARTS OF THE AREA IF THE COLD
AIR REMAINS IN PLACE. WE WILL ADDRESS THIS IN THE HWO LATER THIS
MORNING.

THE MAIN CAVEAT TO THE COLDER SCENARIO IS THAT THE EPAC RIDGE IS
LIKELY TO BE UNDERCUT BY EARLY NEXT WEEK. THIS IS VERY MUCH IN
KEEPING WITH THE CURRENT WARM-PHASE ENSO PATTERN... AND WOULD
INDICATE MODERATION OF THE COLD AIR BY LATE NEXT WEEK. WE ARE
GETTING FAR ENOUGH INTO THE COLD SEASON THAT SYSTEMS IN THE ACTIVE
STORM TRACK FROM THE PACIFIC STILL COULD ENCOUNTER SUFFICIENT COLD
AIR TO PRODUCE ADDITIONAL ROUNDS OF WINTER-TYPE PRECIP IN THE S
PLAINS GOING INTO LATE NEXT WEEK AND BEYOND.

BTW: The low last night here managed to drop to a frigid 17F. Brr.

[iorange55]

The NWS in Norman is still thinking a big southern plains winter weather event is on the table for next week...

DISCUSSION...
STRONG UPPER RIDGE NOW BUILDING OVER EPAC/AK WILL KEEP US IN A COLD
PATTERN FOR THE NEXT WEEK. LONGWAVE TROF WILL BE MAINTAINED
DOWNSTREAM FROM CENTRAL CANADA INTO CENTRAL/W CONUS AS SYSTEM NOW
OVER BRITISH COLUMBIA DROPS S. BASED ON PROJECTED STRENGTH AND
AMPLITUDE OF THE EPAC RIDGE... ASSOCIATED COLD INTRUSIONS OVER THE
NEXT SEVERAL DAYS PROBABLY WILL BE DESERVING OF MORE RESPECT THAN
MOST OF THE MODELS ARE GIVING THEM. THUS WILL LEAN TOWARD COLD SIDE
ON FORECAST TEMPS AND MORE SOUTHERN TRACKS OF THE SURFACE WAVES
ASSOCIATED WITH DISTURBANCES COMING OUT OF THE CENTRAL/WESTERN TROF
SUNDAY AND TUESDAY. THIS LEADS TO A POTENTIALLY INTERESTING SCENARIO
FOR EARLY NEXT WEEK AS THE COLD AIR IS APT TO REMAIN MORE RESILIENT
THAN INDICATED BY THE MODELS. WILL MAINTAIN SOME LOW POPS AROUND
SUNDAY AND HIGHER POPS AROUND TUESDAY. ALTHOUGH THE LESS-AMPLIFIED
UPPER SYSTEM DEPICTED FOR TUESDAY ON THE LATEST ECMWF AND THE GFS
ENSEMBLE IS PREFERRED... THERE IS SOME POTENTIAL FOR A SIGNIFICANT
WINTER WX EVENT FOR AT LEAST NORTHERN PARTS OF THE AREA IF THE COLD
AIR REMAINS IN PLACE. WE WILL ADDRESS THIS IN THE HWO LATER THIS
MORNING.

THE MAIN CAVEAT TO THE COLDER SCENARIO IS THAT THE EPAC RIDGE IS
LIKELY TO BE UNDERCUT BY EARLY NEXT WEEK. THIS IS VERY MUCH IN
KEEPING WITH THE CURRENT WARM-PHASE ENSO PATTERN... AND WOULD
INDICATE MODERATION OF THE COLD AIR BY LATE NEXT WEEK. WE ARE
GETTING FAR ENOUGH INTO THE COLD SEASON THAT SYSTEMS IN THE ACTIVE
STORM TRACK FROM THE PACIFIC STILL COULD ENCOUNTER SUFFICIENT COLD
AIR TO PRODUCE ADDITIONAL ROUNDS OF WINTER-TYPE PRECIP IN THE S
PLAINS GOING INTO LATE NEXT WEEK AND BEYOND.

BTW: The low last night here managed to drop to a frigid 17F. Brr.

That is somewhat encouraging I thought after next week we might let down a little leading up towards Christmas.