Winter Weather Discussion - Jan/Feb 2011

[venture]

That's because the good ol' 18Z GFS run (why this time is always the wonky one) snapped back to predicting over a foot of snow in Central and Western OK...and over 6" in the rest of the state. It'll be back to a drizzle come 00Z. :-P

[Thunder]

Any reasons why these models keep changing? There must be something there that is changing for these models to detect.

[venture]

Just depends how good the data is going into them and how they handle every little calculation. I guess you can look at it from the perspective of the butterfly effect. One little blip somewhere can alter the entire forecast.

[venture]

So tonight's AccuOMGWTForecast continues some of the mania from the 18Z, just repositioned a bit. So first some comments/thoughts.

1) There will be some sort of precip next week, and we'll probably see a flake or two.
2) Things are going to change model wise for the next 4 days.
3) Local media will start hyping more than Mike Apocalypse Morgan.

Now, let's just discuss what things are showing with the understand that this is going to be irrelevant in 6 hours.

January 30th through Midnight February 1
Drizzle to Light Rain will increase through the period. Amounts will be very light, and temps will remain above freezing through the period. South Central OK might see some heavier raid towards the end of the period...possibly over a half inch of rain. Rest of the state will be around a tenth of an inch.

February 1st - Completely inaccurate worst guess forecast map: http://goo.gl/maps/JJ3x
12AM - 6AM: Temps will hover below freezing at the surface, but we'll have a warm layer of air about 1500' up. This would result in freezing rain for the most part during this period. Freezing rain will transition to sleet and snow mix. Transition of course will play havoc with even guessing accumulations right now. Worst guess is around an inch western OK, and 1-3" from Central into NE OK. Liquid precip amounts are over a half inch from OKC to TUL along I-44, but I would imagine a lot of that is probably going to be rain or sleet before full transition to snow happens. Winds will be 20-25 mph during this period.

6AM - 12PM: Temps well below freezing at this point and cold air is established at all levels. Light to Moderate snow looks to continue. Precip forcasts put a band from the TX Panhandle into NW OK and another batch in Central OK to the east. Wind appears to be 15-25 mph. Additional snow accumulation during this period could be as high as 2-4" in the focused areas.

12PM - 6PM: Light snow continues in the West and South, maybe an inch there. Moderate to Heavy snow possible from Central into NE OK. Central into NC Oklahoma can see another 2-4". Areas from just NE of OKC up I-44 to the MO line could see 3-5" of snow.

6PM - 12AM: Light Snow in Central OK to some moderate snow in the east as the storm moves out. Looks like we'll probably dry slot out here in Central sections pretty quick, so this may not really do much. Winds ease back to 10-20 mph. Additional precip amounts are pretty light. Maybe an inch Central to 1-3" East. Could also see freezing drizzle develop in Western OK moving into Central sections.

So if you do the math. The worst case going to change in 6 hours so this is pointless forecast for precip amounts in Central OK...Rain: 0.10", Freezing Rain: 0.1 to 0.25", Sleet/Snow: 6-12". Last part, fresh snow fall could also mean temps could drop quite a bit into the single digits for lows. So we'll just have to watch for that too.

Extended forecast...which like everything else will completely change.

February 4th - Back above freezing.

February 6th - Some Rain/Snow mix in NW OK.

February 8th - Light Rain Central and East.

February 9th - Light Rain/Snow West and East, dry central.

February 10th - Snow...most of OK.

February 11th - Dry and cold.

[Thunder]

These graphics will change after each newscast with weather. Interesting.

[venture]

Some thoughts from NWS Norman...

FIRST PART OF NEXT WEEK IS LOOKING MORE TROUBLESOME IN TERMS OF SNOW AND ICE. MED-RANGE MODELS STILL DIFFER ON TIMING OF THE SYSTEM ARRIVING ON THE OR-CA COAST EARLY SUNDAY AND INTO THE S PLAINS FIRST HALF OF NEXT WEEK. BUT THEY APPEAR TO BE CONVERGING ON A SCENARIO THAT WOULD GIVE US A PRECIP LULL AROUND MONDAY IN WAKE OF THE WEEKEND SYSTEM... FOLLOWED BY INCREASIHG CHANCES MON NIGHT THROUGH TUE NIGHT. PROBLEM IS THAT THE CANADIAN AIR WILL BE ON THE OFFENSIVE DURING THIS PERIOD AND WILL EITHER BE MOVING INTO THE AREA OR WILL ALREADY BE IN PLACE. ECMWF REMAINS MORE AGGRESSIVE THAN THE GFS ON THE ARCTIC HIGH INTRUSION INTO THE S PLAINS MONDAY... AND WOULD BE THE MORE LIKELY SCENARIO IF THERE WERE ALREADY A BIG ARCTIC HIGH AND A LOT OF BITTER COLD AIR UP THERE RIGHT NOW. BUT THERE ISNT. THE ECMWF IN FACT HAS BACKED OFF FROM YESTERDAY`S 1051 HIGH OVER MT AND 504 THICKNESS INTO OK NEXT TUE... BUT MODEL CONSENSUS STILL SUPPORTS A 1040-SOMETHING HIGH INTO THE N PLAINS MONDAY WHICH WILL PUSH COLDER AIR INTO THE REGION WHILE THE UPPER SYSTEM APPROACHES FROM NM. FORECAST THUS PRESENTS A MORE GRADUAL CHILLDOWN OVER THE SUNDAY-TUESDAY PERIOD - BUT A SIGNIFICANT ONE NONETHELESS. LARGE-SCALE EVOLUTION OF FEATURES ON CURRENT MED-RANGE MODELS IS PRETTY TYPICAL OF A HEAVY-SNOW EVENT IN THE S PLAINS... BUT THE MORE GRADUAL INJECTION OF LOW-LEVEL COLD AIR SUGGESTS A CONCURRENT POTENTIAL FOR A PERIOD OF ICE BEFORE THE COLD AIR WINS OUT AND SNOW PREVAILS BY THE END OF THE EVENT. POPS HAVE BEEN INCREASED
MON NIGHT INTO TUE NIGHT PER LATEST GFS GUIDANCE. TEMPS LATE IN THE FORECAST AGAIN ARE CLOSE TO LATEST HPC GUIDANCE.

SYSTEM NEXT WEEK COULD GO IN ANY OF SEVERAL DIRECTIONS - MOSTLY SNOW OR MOSTLY ICE OR SOME OF EVERYTHING. WOULD NOT EVEN BE SURPRISED AT COLD AND DRY WITH LITTLE OR NO PRECIP GIVEN THE WAY THINGS HAVE BEEN GOING LATELY. WE WILL HIT IT A LITTLE HARDER IN THE HWO... BUT WILL EMPHASIZE THE EXISTING UNCERTAINTIES ON DETAILS INCLUDING TIMING...AMOUNTS... AND PRECIP TYPE/S.

[venture]

12Z GFS is keeping the trend of a Winter Storm for Monday into Tuesday.

January 31st - Map: http://goo.gl/maps/vJgX

Precip will be fairly light. Some light drizzle/rain will transition quickly to flurries/light snow in the northwest. Maybe a dusting up to an inch there. Southeast will see mostly rain for now, though it will be light. The rest of the state will be anybodies guess right now. Right now it appears it will start as light rain and transition (from NW to SE) into a freezing rain, sleet, and then snow situation. Precip will be mostly light but will start picking up in intensity over night going into the 1st. Could see a glaze of ice around 0.10 of an inch in places. Also sleet and snow accumulations could be around an inch as well. Mostly likely area for the wintry accumulation will be the western half of the outlined area. Northeast OK may stay rain a bit longer.

February 1st - Map: http://goo.gl/maps/UYVN

Winter storm begins to get into full swing. Central OK looks like it will be pretty much snow for the entire 24 hour period, but could still see some sleet mixing in for the first few hours. Winds look like they'll be around 10-20 mph for most of the day. Temps will start around 30 early and fall to around 20 through the day. Precip amounts still look pretty crazy, but I'm not going to bother repeating my disclaimer again...everyone knows the drill by now. Peak time for snow for the OKC metro looks like around mid day as the models paint a little bullseye right over us indicating precip amounts around a half inch (liquid) during that 6 hour period. So depending on snow crystal quality, that could be around an inch an hour snowfall rates. Snow will begin to push off to the east through the evening, ending in the southwest first. NE OK may still see some accumulating snow up to midnight.

Long range sneak peak still has something towards the middle of the month, but not even going to worry about it right now.

[Thunder]

KFOR's 7-Day graphic is very interesting. Last night from Mike was not so bad. This morning from David was very frightening. And now from Troy is being quite soft on all this. Very interesting to see the different opinions at the same station.

[OKCisOK4me]

Well, I'm gonna be a cheerleader for DRY SLOT on Tuesday cause I have bowling league on Tuesday nights and I want to bowl next week!

[venture]

Well, I'm gonna be a cheerleader for DRY SLOT on Tuesday cause I have bowling league on Tuesday nights and I want to bowl next week!

LOL. Yeah...but personally, i'd rather not have the state burn down from it being so dry. Take whatever moisture we can get at this point.

[OKCisOK4me]

LOL. Yeah...but personally, i'd rather not have the state burn down from it being so dry. Take whatever moisture we can get at this point.

Nothing will ever be as bad as January 1st, 2006. There were like 15 grass fires in central Oklahoma that New Years Day. It smelled like a roast in Edmond!

[venture]

Norman Update...

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORMAN OK
338 PM CST THU JAN 27 2011

.DISCUSSION...
VERY WARM TEMPERATURES ARE IN STORE FOR THE NEXT COUPLE OF DAYS...ALTHOUGH THERE IS SOME DISAGREEMENT IN THE MODELS ABOUT HOW FAR A COLD FRONT WILL MOVE SOUTH ON SATURDAY. GFS BRINGS FRONT INTO THE NORTHERN THIRD OF THE CWA BY 00Z/SUNDAY WHILE ECMWF AND ESPECIALLY THE NAM KEEP THE FRONT NORTH OF THE AREA. IN COORDINATION WITH THE ADJACENT KANSAS OFFICES... WILL GO CLOSER TO THE WARMER NAM SOLUTION FOR SATURDAY AT THIS POINT. ALL THE MODELS DO SHOW THE COLD FRONT MOVING THROUGH THE AREA SATURDAY NIGHT AND SUNDAY MORNING BEGINNING A MUCH COOLER PERIOD OF TIME. REINFORCING SHOTS OF COLD AIR LOOKS TO COME IN EARLY NEXT WEEK WITH TEMPERATURES COLDEST TEMPERATURES EXPECTED ON TUESDAY AND WEDNESDAY.

PRECIPITATION FORECAST IS STILL TRICKY. AT LEAST SLIGHT PRECIPITATION CHANCES BEGIN ON SATURDAY NIGHT AND PERSIST INTO EARLY NEXT WEEK. MEDIUM RANGE MODELS DO INCREASE THE PRECIPITATION CHANCES NEXT WEEK ALTHOUGH THERE ARE SIGNIFICANT DIFFERENCES IN THE LOCATION AND TIMING OF THE PRECIPITATION... AND STILL UNCERTAINTY ON PRECIPITATION TYPE ESPECIALLY EARLY IN THE EVENT. SURFACE FRONT WILL BE WELL TO THE SOUTH OF THE AREA AND ISENTROPIC ANALYSIS SHOWS DECENT MOISTURE FEED AND LIFT ABOVE THE FRONTAL SURFACE... BUT NOT IN THE TYPICAL CONFIGURATION FOR US. INSTEAD OF A MOIST SOUTHERLY FLOW ABOVE THE FRONTAL SURFACE... THE MOIST FLOW IS A EAST TO WEST FLOW FROM ARKANSAS DESPITE THE LACK OF A STRONG LOW-LEVEL CYCLONE. SO THERE IS THE UNCERTAINTY ABOUT MOISTURE AVAILABILITY FOR THE STORM SYSTEM EARLY NEXT WEEK ESPECIALLY GIVEN THE POOR TRACK RECORD OF THE MOISTURE RETURN IN THE MODELS WITH SOME OF THE RECENT NON-EVENTS. REGARDLESS AT THIS POINT... CHANCE POPS ARE WARRANTED ON MONDAY NIGHT TO TUESDAY NIGHT ALTHOUGH GEOGRAPHIC AND SIGNIFICANCE DETAILS ARE STILL VERY
MUCH IN QUESTION. AND AT THIS POINT ALL OF THE MEDIUM RANGE MODELS SUGGEST THAT PRECIPITATION WILL END TUESDAY NIGHT SO WEDNESDAY AND THURSDAY ARE DRY AND WARMING IN THIS PACKAGE.

[Thunder]

Just to update on the above graphics before it changes.

Mike's latest thinking... and it is a major change from Troy's calm forecast.

Major Winter Storm Possible
- Ice for Monday
- Snow for Tuesday

Second Graphic
- Bitter Ice then Snow
- Life Threatening Weather Very Possible

So, to look at it from a broad state-wide view, I guess that all of these statements is correct. There will be ice somewhere. There will be snow somewhere. There will definitely be serious cold across most of the state. Life Threatening, yes, depend on how you look at it... Idiots dangerously driving to their doom. Electricity outage, no heat, death is imminent.

We have to admit that Mike's fear tactics is good and serves as a wake-up call to everyone to PREPARE and BRACE FOR IMPACT. Best go stock up on vital supplies before it gets too late when the stores is in chaos with depleted supplies.

[bandnerd]

Better go out and get 20 gallons of milk and 50 loaves of bread. I never know what people plan to do with those items during an ice storm/potential power outage.

Everyone panic!!!

[OKCisOK4me]

Thunder, lol, I was about to do an update on MM's Armageddon forecast. You better get a cot and take it to work with you cause it sounds like you're gonna be stuck there bagging a ton of groceries for everyone on the east SIIIIIIIIIIIDDE!!

[adaniel]

Better go out and get 20 gallons of milk and 50 loaves of bread. I never know what people plan to do with those items during an ice storm/potential power outage.

Everyone panic!!!

I never got why people felt the need to buy 6 loaves of bread for the possibility of being stuck in the house for a maximum of 2 days.

[Easy180]

70 for 3 days straight...Thinking the ground temps will be still be in the 50's when the crap hits

Love the "Life threatening weather" line...good lord

[Thunder]

Thunder, lol, I was about to do an update on MM's Armageddon forecast. You better get a cot and take it to work with you cause it sounds like you're gonna be stuck there bagging a ton of groceries for everyone on the east SIIIIIIIIIIIDDE!!

Fortunately, I am on medical leave until Summer (prefer to wait until after Spring due to La Nina's major tornado outbreaks season). Until then, I can enjoy the wide weather varieties with Venture. <3

[Thunder]

I never got why people felt the need to buy 6 loaves of bread for the possibility of being stuck in the house for a maximum of 2 days.

If there are massive power outages, it can take weeks for power to restore. It makes logical sense to stock up on bread, but not for milk, unless they plan to leave them outside in the coolers. Oh, what a world!

[venture]

70 for 3 days straight...Thinking the ground temps will be still be in the 50's when the crap hits

Love the "Life threatening weather" line...good lord

Grounds temps are still in the low 40s. There will be some melting initially (if we go by the doomsday forecast) thanks to the temp and liquid precip. However, snowfall rates and plummeting temps will likely overcome that pretty fast. Anywho...this forecast is going to change a dozen more times, so we'll see what happens.

[Andrew4OU]

Grounds temps are still in the low 40s. There will be some melting initially (if we go by the doomsday forecast) thanks to the temp and liquid precip. However, snowfall rates and plummeting temps will likely overcome that pretty fast. Anywho...this forecast is going to change a dozen more times, so we'll see what happens.

Wasn't it 60-70 degrees the day before the 2009 Christmas Eve Blizzard?

[Bostonfan]

Wasn't it 60-70 degrees the day before the 2009 Christmas Eve Blizzard?

I believe so... It seems most of our big winter storms come on the heels of very mild temps just days before.

[venture]

I believe so... It seems most of our big winter storms come on the heels of very mild temps just days before.

It does seem to be a pretty common occurrence around here. :-P

00Z GFS is coming in now and seems to move the highest snowfall totals west a bit. Will post a full recap when it is done loading.

[adaniel]

Just got done watching Mike Morgan...all I can say is WOW. I am actually startled! This storm is going to be "life threating" and maybe only "a notch" below the Christmas Eve blizzard with at least a half foot if not more of blowing/drifting snow.

Who wants to storm the grocery store with me tommorow?

[Andrew4OU]

Just got done watching Mike Morgan...all I can say is WOW. I am actually startled! This storm is going to be "life threating" and maybe only "a notch" below the Christmas Eve blizzard with at least a half foot if not more of blowing/drifting snow.

Who wants to storm the grocery store with me tommorow?

Only if we can buy half a dozen loaves of bread each.