General Weather Discussion - December, 2015

[Anonymous.]

A lot of sleet coming down with this wave. icing looks minimal thus far. Roads are definite sleet and snow covered, though.

Most of the OKC area is right at freezing, with north and west sides bumping from 31F to 32F.


New NAM shifts the low's track further south and east again (this is the 4th run in a row). Producing some intense wrap-around snow overnight.

Weirdly enough, the GFS has actually shifted the track back to the north and west.



The battle of 32F is setting up directly over OKC. We will have to see how it moves about today, one thing going for us - is the main precipitation is hitting during daylight hours - so some radiation melting will be occurring.

[Anonymous.]

BTW, Ice Storm Warning has been extended a tier of counties further south:




As the sleet keeps coming down, it will help cool the air column and prevent too much freezing rain. However, roads will deteriorate quicker with sleet falling, melting - then refreezing.

[Anonymous.]

One concern is that the sleet accumulating will keep the surface cold enough, and as the low comes out, more warmer air overrides in the upper levels of the atmosphere - causing freezing rain threat to increase.

[therondo]

We have some moderate sleet in MWC.

[Pete]

Still sleeting like crazy but also getting some light snow mixed in.

[liirogue]

Ice starting to accumulate on trees in Yukon

[Anonymous.]

MD is out in regards to the rest of this afternoon:



SUMMARY...WINTER MIXED PRECIPITATION WILL CONTINUE ACROSS MUCH OF
WRN/NRN OK THROUGH THE AFTERNOON...AND SHOULD INCREASE IN
COVERAGE/INTENSITY ACROSS PORTIONS OF W TX THROUGH 22Z.

DISCUSSION...AS A CLOSED UPPER LOW S OF EL PASO TX THIS MORNING
MOVES EWD TO THE BIG BEND REGION OF W TX BY THIS AFTERNOON...
WIDESPREAD PRECIPITATION WILL LIKELY CONTINUE ACROSS MUCH OF
WRN/NRN/CNTRL OK. ADDITIONAL PRECIPITATION IS FORECAST TO DEVELOP
AND MOVE NWD OVER PORTIONS OF W TX THROUGH THE AFTERNOON AS WELL. A
CORRIDOR OF CONVECTIVELY ENHANCED WINTER MIXED PRECIPITATION...
INCLUDING FREEZING RAIN...SLEET...AND SNOW IS EXPECTED IN A NNE-SSW
CORRIDOR FROM NRN OK SWD TOWARDS THE INTERNATIONAL BORDER. A
PRONOUNCED +6.5 DEG C WARM NOSE ALOFT PRESENT ON THE 12Z SOUNDING
FROM NORMAN OK SHOULD ENSURE THAT MOST HYDROMETEORS FALLING THROUGH
THIS LAYER SHOULD PARTIALLY/COMPLETELY MELT IN OK...AND THEN
REFREEZE WHERE SFC WET-BULB TEMPERATURES HAVE FALLEN BELOW FREEZING.
ADDITIONAL OBSERVED SOUNDINGS FROM LAMONT OK...DODGE CITY KS...AND
AMARILLO TX SUGGEST THAT THE LOW-LEVEL WARM NOSE IS LESS PRONOUNCED
WITH NWD/WWD EXTENT...AND A TRANSITION FROM FREEZING RAIN TO SLEET
TO SNOW SHOULD OCCUR FROM E TO W ACROSS THE MCD AREA THROUGH THE
AFTERNOON AS THE UPPER LOW PROGRESSES EWD AND MID-LEVEL TEMPERATURES
CONTINUE TO COOL. FREEZING RAIN RATES UP TO 0.10 INCH/HR MAY BE
POSSIBLE IN AREAS OF MODERATE PRECIPITATION ACROSS OK.

FURTHER S ACROSS PORTIONS OF W TX...A MID TO UPPER-LEVEL DRY SLOT
PRESENT ON WATER VAPOR SATELLITE IMAGERY IS MOVING NWD ACROSS THIS
REGION...WHICH HAS SUPPRESSED WIDESPREAD PRECIPITATION ACTIVITY THUS
FAR. HOWEVER...RECENT RADAR IMAGERY DEPICTS A BAND OF LIGHT TO
MODERATE PRECIPITATION EXTENDING FROM SERN NM SEWD INTO NRN
MEXICO...MOVING NWD WITH TIME. INITIAL PRECIPITATION ACROSS SRN
PORTIONS OF THE MCD AREA SHOULD BE MAINLY A MIX OF SLEET/FREEZING
RAIN. BUT WITH ADDITIONAL LOW TO MID-LEVEL COOLING FORECAST ACROSS W
TX LATER THIS MORNING INTO THE EARLY AFTERNOON AS THE UPPER LOW
APPROACHES...A TRANSITION TO ALL SNOW SHOULD SLOWLY OCCUR FROM SW TO
NE.

..GLEASON.. 12/27/2015

[Anonymous.]

NWS cancelling warnings across SW Kansas in response to the new track guidance given by models.

The heaviest snow looks like it could be laid just west of OKC. Any further deviations south will bring that swath with it. it is going to be a very narrow corridor of heavy accumulation.

[OKCRT]

NWS cancelling warnings across SW Kansas in response to the new track guidance given by models.

The heaviest snow looks like it could be laid just west of OKC. Any further deviations south will bring that swath with it. it is going to be a very narrow corridor of heavy accumulation.

So 4-8 inches of snow for NW OKC? That is what the worthless channel is saying.

[corwin1968]

I just returned from driving in the areas bordered by NW 178th, NW 164th, Western & May and the roads are slick. I wouldn't call them hazardous because a little caution is sufficient but you will slide out while turning if you aren't careful.

[Achilleslastand]

So 4-8 inches of snow for NW OKC? That is what the worthless channel is saying.

The big 3 were pretty much in consensus that the metro was getting 2-4.

[Anonymous.]

Here is my thinking based on current nowcast situation with the low coming out in SW TX.

Any variances in the track to the south or north will pull the heavy snow with it. We are talking just 10-20 miles being a huge difference.

Again this is for precipitation starting tonight. Currently the dryslot if filling in across NW TX with convective thunderstorms overriding up into the cold air sector. This will continue to fill in across SW OK and push over the state as the main low deepens.

[OKCRT]

Here is my thinking based on current nowcast situation with the low coming out in SW TX.

Any variances in the track to the south or north will pull the heavy snow with it. We are talking just 10-20 miles being a huge difference.

Again this is for precipitation starting tonight. Currently the dryslot if filling in across NW TX with convective thunderstorms overriding up into the cold air sector. This will continue to fill in across SW OK and push over the state as the main low deepens.

If that Low comes down 50 miles further to the east OKC would get dumped on. It appears from looking at the radar OKC area is in a dry slot.

[Bobby821]

Mike Morgan posted this a few minutes ago:

https://twitter.com/MikeMorganKFOR/s...rc=twsrc%5Etfw

[Anonymous.]

Yikes! Okay the low is sinking further south in TX, it was forecasted to have already made the turn north/northeast. It is tracking south east to the south of San Angelo, TX.

[Bobby821]

Yikes! Okay the low is sinking further south in TX, it was forecasted to have already made the turn north/northeast. It is tracking south east to the south of San Angelo, TX.

SO I am guessing by this and everything else I have been reading about the track of the low this means OKC is in the bullseye for heavy snow tonight?

[Bobby821]

Timeline from Mike Morgan on what to expect: I am guessing this is real and not hype based on what Anon posted above.

https://twitter.com/MikeMorganKFOR

[OkieHornet]

when mm says "record okc snowfall", okc's record for a day is what, 11-12"

news still has okc in the 1-4" range.

[OKCRT]

Timeline from Mike Morgan on what to expect: I am guessing this is real and not hype based on what Anon posted above.

https://twitter.com/MikeMorganKFOR

Sounds like hype to me. It's not doing anything right now and the radar shows heavy rain to the east and not moving toward OKC. Looks like we are in that dry slot they were talking about. And weather channel now showing less than an inch in okc area.

[Achilleslastand]

Sounds like hype to me. It's not doing anything right now and the radar shows heavy rain to the east and not moving toward OKC. Looks like we are in that dry slot they were talking about. And weather channel now showing less than an inch in okc area.

W/e we are going to get wont be here until the overnight hours.

[bradh]

Total waste of time forecasting winter storms. Nowcasting is the only thing that works. Weathermen should just be on air to provide road conditions during the winter.

[NikonNurse]

Sounds like hype to me. It's not doing anything right now and the radar shows heavy rain to the east and not moving toward OKC. Looks like we are in that dry slot they were talking about. And weather channel now showing less than an inch in okc area.

You are obsessed with this dry slot. I had tons at least 2 inches of sleet this morning up in Piedmont. Now from ANON and Mike Morgan, I'm assuming that this isn't a lucky dry slot right now...Its the calm before the ACTUAL storm arrives later tonight...The question was where the low tracked....If it spit out where it's spitting out now or any further south...we ., in OKC , were to get a massive blizzard. The dry slot was a ray of hope if it tracked further north......so is it safe to assume from ANONs that the dry slot wish went home with Santa??!! I would much rather have 3 feet of snow then any ice.....

[Anonymous.]

I have revised my own map from earlier based upon nowcast setup and the latest model data:

Thunder snow will be possible closest to the actual low's center. This will be right on the edge of the freezing line as elevated storms and showers will develop on the "warm" eastern side and ride across from east to west over the freezing line. This is where snowfall rates could be 2" per hour or more.

[silvergrove]

I have revised my own map from earlier based upon nowcast setup and the latest model data:

Thunder snow will be possible closest to the actual low's center. This will be right on the edge of the freezing line as elevated storms and showers will develop on the "warm" eastern side and ride across from east to west over the freezing line. This is where snowfall rates could be 2" per hour or more.

Although we're sort of in a nowcasting situation, what's the rough general timeline for this to go down?

[OKCRT]

You are obsessed with this dry slot. I had tons at least 2 inches of sleet this morning up in Piedmont. Now from ANON and Mike Morgan, I'm assuming that this isn't a lucky dry slot right now...Its the calm before the ACTUAL storm arrives later tonight...The question was where the low tracked....If it spit out where it's spitting out now or any further south...we ., in OKC , were to get a massive blizzard. The dry slot was a ray of hope if it tracked further north......so is it safe to assume from ANONs that the dry slot wish went home with Santa??!! I would much rather have 3 feet of snow then any ice.....

I am not the one that came up with the Dry Slot but it does appear that OKC is in the DRY SLOT right now. Maybe we will wake up in the morning with 10+ inches of snow as the DRY SLOT leaves us behind. But then again maybe the DRY SLOT hangs around. Weather channel has less than 1 inch in OKC.