February '10 Weather Discussion

[venture]

Bostonfan, don't pay much attention to NWS. lol The storm is coming and it will be here, no matter how delayed NWS is.

That is a stupid way to look at it. I'm going to take OUN over any local yahoo on the TV. OUN is also spends more time actually analyzing the weather and forecast models than any TV meteorologist will. Majority of the guy son TV just copy and paste the OUN/NWS forecast because they are too busy doing other things.

[westsidesooner]

Again I have to agree with V. Oun isnt in the buisness of jumping the gun. And all long term forecasts/models have to be taken for what they are. And you have to remember, especially in this neck of the woods, after all this is Oklahoma, even short term forecasts can be very tricky, such as where a dryline will set up in the spring, or the speed of advancing cold fronts. Even a few miles difference a few hours out can make the difference between severe storms and tornadoes.....or windy and dry. Thats what makes it so much fun living here.

I'm soooooo ready to start talking about drylines though....and to see those first few towers (cumulonimbus) going up. I CAN HARDLY WAIT.

BTW....For those of you in Austin...hows the level of Lake Travis doing? I see on drought monitor that the conditions have improved down there.

[venture]

Perfect example today of why models can be so reliable in the extended period. 18Z GFS is TOTALLY different from 00Z GFS. One has a major snow storm, the evening one has maybe a little snow.

[venture]

Evening GFS and NAM paint a fairly quiet pictures coming up, after this weekend.

Some heavy rain, a storm or two, across the state towards the end of the weekend. Right now both models agree on moving the vast majority of precip out before colder air moves in that would cause a change over. However, some snow might mix in on the very back edge or in northern OK.

Extended, the only real focus of precip is around th 28th/1st, but this is all less than a quarter inch and temps well above freezing.

Nothing else for now in the extended. Nearly everything next week misses us to the south.

[venture]

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1257 AM CST FRI FEB 19 2010

VALID 201200Z - 211200Z

...NO SVR TSTM AREAS FORECAST...

...SYNOPSIS...
00Z NAM/GFS AND 12Z ECMWF ARE FAIRLY CONSISTENT WITH THE ARRIVAL OF
A COMPACT SHORTWAVE TROUGH TO THE SRN CA COAST BY 12Z SATURDAY. THIS
SYSTEM WILL PROGRESS EWD THROUGH AN EXISTING QUASI-ZONAL FLOW REGIME
ACROSS THE CENTRAL AND SRN TIER OF STATES...WITH THE TROUGH MOVING
THROUGH THE SWRN STATES TO THE SRN HIGH PLAINS/W TX BY 12Z SUNDAY.

IN THE LOW LEVELS...A SURFACE LOW IS FORECAST TO DEVELOP OVER ERN NM
ALONG THE SRN PORTION OF A LEE TROUGH...WITH DEEPENING OF THIS LOW
BEING AIDED BY THE APPROACH OF THE SRN CA SHORTWAVE TROUGH. THIS
AREA OF LOW PRESSURE WILL MOVE EWD INTO NWRN TX LATE DAY 2 ALONG A
BOUNDARY WHICH SHOULD EXTEND ENEWD THROUGH OK TO SRN MO.

...OK/NRN TX...
SRN HIGH PLAINS SURFACE CYCLOGENESIS WILL SERVE TO ENHANCE SLY
LOW-LEVEL WIND FIELD OVER THE SRN PLAINS ON SATURDAY...ALLOWING FOR
THE GRADUAL MOISTENING OF THE BOUNDARY LAYER TO THE S OF THE ENEWD
EXTENDING BAROCLINIC ZONE IN OK/SRN MO. HOWEVER...AS INDICATED IN
THE PREVIOUS DAY 3 OUTLOOK FOR THIS PERIOD...NO DIURNAL STORMS ARE
EXPECTED AS CAP STRENGTH RELATIVE TO MOISTURE QUALITY WILL RESULT IN
LITTLE OR NO CONVECTIVE INSTABILITY.

INCREASING LOW LEVEL WAA ACROSS E TX LATE SATURDAY AFTERNOON/EARLY
EVENING MAY SUPPORT A FEW ELEVATED TSTMS. HOWEVER...A MARKED
INCREASE IN AREAL COVERAGE OF MAINLY ELEVATED TSTM ACTIVITY IS
EXPECTED SATURDAY NIGHT NWWD ACROSS MUCH OF OK AND N TX. COMBINED
EFFECTS OF ADDITIONAL LOW-LEVEL MOISTURE/WARM AIR ADVECTION ALONG A
STRENGTHENING SRN PLAINS SSWLY LLJ AND STEEPENING MID LEVEL LAPSE
RATES WILL RESULT IN MARGINAL INSTABILITY /MUCAPE 250-500 J/KG/ NEAR
AND N OF THE SURFACE BOUNDARY. ELEVATED TSTMS ARE FORECAST TO
DEVELOP WITHIN THIS ZONE OF DESTABILIZATION FROM PARTS OF W TX
/INCLUDING ERN TX PANHANDLE/ THROUGH OK/N TX TO INTO AR/SRN MO. A
FEW STORMS MAY BECOME STRONG AND CAPABLE OF PRODUCING HAIL NEAR
SEVERE CRITERIA ACROSS OK AND FAR N TX

[venture]

Just for far NW OK...



MESOSCALE DISCUSSION 0133
NWS STORM PREDICTION CENTER NORMAN OK
1113 PM CST SAT FEB 20 2010

AREAS AFFECTED...FAR NW OK...CNTRL SRN AND ERN KS

CONCERNING...FREEZING RAIN

VALID 210513Z - 211115Z

BURSTS OF MODERATE TO HEAVY FREEZING RAIN WILL BE POSSIBLE LATE THIS
EVENING AND OVERNIGHT FROM FAR NWRN OK INTO MUCH OF S CNTRL AND E
CNTRL KS. A QUICK 0.10" TO 0.25" WILL BE POSSIBLE.

ISENTROPIC LIFT N OF A STATIONARY FRONT ACROSS OK WILL PERSIST AS AN
UPPER TROUGH LIFTS EWD ACROSS NM AND INTO TX AND OK. A WARM NOSE
ALOFT NEAR 850 MB WILL REMAIN ACROSS MUCH OF SRN AND ERN KS...WITH
SUB-FREEZING TEMPERATURES AT THE SURFACE. STEEP MID LEVEL LAPSE
RATES AND INCREASING THETA-E AROUND 850 MB WILL RESULT IN MARGINAL
CONVECTIVE INSTABILITY AND THE LIKELIHOOD OF ELEVATED THUNDERSTORMS.
THESE STORM CORES MAY PRODUCE LOCALIZED BURSTS OF HEAVY FREEZING
RAIN...POSSIBLY MIXED WITH SLEET OR HAIL ESPECIALLY WITH NWWD EXTENT
WHERE THE COLUMN WILL BE COOLEST.

[Andrew4OU]

Can anyone enlighten us on the systems coming this weekend? Seems like KFOR is revving up the winter storm machine again.

[venture]

I'll post some thoughts later, wanted to see a new set of models this evening. Since GFS and NAM were on totally different planets earlier.

[Thunder]

After this weekend, we'll be having a brand new total snowfall record. Something to be proud for OKC!

[venture]

Quick look through the models. First system for Thurs-Fri looks like mostly just rain from the metro. Some accumulating snow possible from NC to Eastern OK - which the majority to the east. A swath of 2-3 inches looks about right for right now. Late weekend system looks like a mainly Red River snow system, which most accumulations confined to down there and relatively nothing up here.

It does stand to note that models are flipping quite a bit right now. I would put confidence in any forecast right now pretty low since there isn't any substantial stability with the forecasts. Anyone who says a major winter storm is on the way, well, beat them with a baseball bat. Not going to happen. However, there will be snow in the state and some ares will get white. OKC - not so much as it stands now.

[venture]

Norman sums up what I'm seeing pretty well.

[Thunder]

Anyone who says a major winter storm is on the way, well, beat them with a baseball bat. Not going to happen.

It is still major for Oklahoma, no matter where in the state.

[venture]

It is still major for Oklahoma, no matter where in the state.

I would hope by now we've gone past the feeling of a snow flake = major winter catastrophe.

Update snowfall forecast map.

[venture]

Models still not solid on what is going to happen. Timing and precip type still differs between the two primary models. Also, a lot of things still in flux. One...temps will be in the 40s at the start of this with ground temps pretty warm. There is also a surge of warmer air expected later in the day on Thursday, that may cause havoc with the change over. Regardless, there should be some areas that are white when Friday morning comes around. I'm going to post current "worst" case scenario snow fall amounts and we'll see how things evolve as models tune in a bit better. This will be a wet snow, so we'll be looking at low snow to liquid ratio here...maybe an 8 to 1 instead of 10 to 1 or higher like we are use to.


GFS...
Thursday 9PM - Light Rain/Snow mix. Trace accumulation.
Friday Midnight - Snow be primary at this point. 0.1" of accumulation.
Friday 3AM - Snow. 0.1-0.2" of accumulation.
Friday 6AM - Snow. 0.1-0.25" of accumulation.
Friday 9 AM - Light Snow. <0.1" of accumulation.

NAM...
Friday 3AM - Light Rain/Snow Mix. <0.1" of accumulation.
Friday 6AM - Light Snow with some Rain mixing still. 0.1" of accumulation.
Friday 9AM - Light Snow, some rain maybe. Dryslotting from the SW. 0.1" of accumulation.
Friday 12PM - Light Snow/Rain mix. <0.1" of accumulation.
Friday 3PM - Light Rain/Snow. Trace.

So GFS is pushing snow the most...max around 4-6" of snow if it was pure snow. NAM is much warmer and keeping things mixed that will likely limit any snow accumulation to an inch or less in most areas - if anything at all. NAM also showcases a sharp dry slot coming in from the SW that comes right up to the Metro and could setup where the city proper gets nothing, but Northern and Eastern sides pick up a couple inches.

[venture]

Winter Weather Advisory out...

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE NORMAN OK
1130 AM CST THU FEB 25 2010

OKZ013-018>020-023>032-040>043-260500-
/O.NEW.KOUN.WW.Y.0011.100226T0600Z-100226T1800Z/
NOBLE-KINGFISHER-LOGAN-PAYNE-CADDO-CANADIAN-OKLAHOMA-LINCOLN-
GRADY-MCCLAIN-CLEVELAND-POTTAWATOMIE-SEMINOLE-HUGHES-GARVIN-
MURRAY-PONTOTOC-COAL-
INCLUDING THE CITIES OF...PERRY...KINGFISHER...GUTHRIE...
STILLWATER...ANADARKO...YUKON...EL RENO...MUSTANG...
OKLAHOMA CITY...CHANDLER...CHICKASHA...PURCELL...NORMAN...M OORE...
SHAWNEE...SEMINOLE...HOLDENVILLE...PAULS VALLEY...SULPHUR...ADA...
COALGATE
1130 AM CST THU FEB 25 2010

...WINTER WEATHER ADVISORY IN EFFECT FROM MIDNIGHT TONIGHT TO
NOON CST FRIDAY...

THE NATIONAL WEATHER SERVICE IN NORMAN HAS ISSUED A WINTER
WEATHER ADVISORY FOR SNOW... WHICH IS IN EFFECT FROM MIDNIGHT
TONIGHT TO NOON CST FRIDAY ACROSS PORTIONS OF CENTRAL AND SOUTHERN
OKLAHOMA.

* TIMING: FROM MIDNIGHT THROUGH FRIDAY MORNING

* MAIN IMPACT: SNOW ACCUMULATION UP TO 4 INCHES.

* OTHER IMPACTS: SNOW WILL PRIMARILY ACCUMULATE ON GRASSY
SURFACES. HOWEVER... SOME SNOW ACCUMULATION MAY OCCUR ON
ROADWAYS CAUSING SLUSHY AND SLICK CONDITIONS.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

BE PREPARED FOR SLIPPERY ROADS AND LIMITED VISIBILITIES...AND USE
CAUTION WHILE DRIVING.

[silvergrove]

How does this Sunday look in terms of wintry weather?

[venture]

Majority of the precip should be in Southern OK and surface temps will be above freezing. So if there is any snow, it'll melt pretty quick.

[OKCisOK4me]

I sure hope the next storm is exactly like this one. I'm tired of Thunder wishing for destruction and mayhem...

[Thunder]

I sure hope the next storm is exactly like this one. I'm tired of Thunder wishing for destruction and mayhem...

I just wanted to break the record.

[SkyWestOKC]

I wouldn't mind breaking some heat records right now. Brrr.

[venture]

I wouldn't mind breaking some heat records right now. Brrr.

If mid 70s were record highs I would be with you, but they are a bit above that. I really should just move to San Diego...but damn my love of spring time here.