Gonna give this one its own thread. Concern for our state is now on the developing winter storm that is pegged to come in over the next couple days. Norman WFO has tossed up a Winter Storm Watch (National Weather Service Watch Warning Advisory Summary (http://forecast.weather.gov/showsigwx.php?warnzone=OKZ015&warncounty=OKC043&firewxzone=OKZ015&local_place1=4+Miles+NNE+Camargo+OK&product1=Winter+Storm+Watch)) for the counties expected to be most effected. Snow fall forecasts seem to be up in the air since some models are extremely aggressive (upwards of 20 inches) and others are just terrible with winter storms. Ground temperatures are all in the low to mid 50s throughout the state, so the rate of snowfall would need to be great for it to stick - which it should be.

I'm going to focus on the OKC metro for this first post. Going to throw up what a model is thinking (will get more when I have time to take a closer look). My thought son snowfall rates will be mitigated a bit...living in the Great Lakes for several years, these type of forecasts are the hardest to do.

GFS has OKC falling below freezing in the late afternoon on Friday. Precip will already be ongoing at this time with some light to moderate rain. This will likely mix over and change to show, upper levels will be cold enough to have frozen precip all the way down. Through the course of the event (Saturday morning) total water content will be around .4" to 1.00", which typically would translate into 4 to 10 inches of snow (this isn't the north where you have a higher water to snow ratio). However, this snow is likely to be pretty heavy with a lot of water content, so with compacting in mind ground accumulations would likely be anywhere from 2 to 5 inches. Higher values on the north side, lower from Norman south. Winds will be on the order of 15-25mph with much higher gusts during the event, so visibilities will be low.

I won't post regarding WRF, since it keeps temps no lower than 40 here in Central Oklahoma which would lead to just cold rain. Will update with the new model runs later this evening.

I just posted a snowfall forecast chart in another thread. I wouldn't be surprised to see the watch upgraded by tomorrow, if the models are correct. The SPC has also expanded the severe weather area for tomorrow to include most of central and eastern Oklahoma. Mostly for hail. Gotta love spring.

Yeah, it is almost a given the watch area will get upgrade. Granted the criteria used here is completely different than back north which really annoys me to a point - a flurry doesn't require a winter weather advisory (yes...not f'n travelers advisory Gary and Mike).

Here is the SPC Outlook Westside pointed out.

...SOUTHERN PLAINS INTO THE OZARK PLATEAU...
WARMING MID-LEVELS AHEAD OF STRONG DIGGING UPSTREAM TROUGH WILL CONTRIBUTE TO INCREASED INHIBITION ACROSS MUCH OF THE SOUTHERN PLAINS...PARTICULARLY SOUTH OF THE WARM FRONT FORMING NEAR THE RED RIVER...TO THE EAST OF THE DEVELOPING SURFACE CYCLONE. IT IS POSSIBLE THAT ISOLATED CONVECTIVE DEVELOPMENT...IN AN ENVIRONMENT FAVORABLE FOR SUPERCELLS...MAY OCCUR NEAR THE DRY LINE/WARM FRONT INTERSECTION ACROSS PARTS OF NORTH CENTRAL TEXAS/SOUTH CENTRAL OKLAHOMA LATE THURSDAY AFTERNOON. BUT...IT APPEARS MORE PROBABLE THAT THE PRIMARY CONVECTIVE DEVELOPMENT WILL OCCUR AFTER DARK... BASED IN AN ELEVATED WARM ADVECTION REGIME TO THE NORTH OF THE FRONT...ACROSS PARTS OF CENTRAL/EASTERN OKLAHOMA INTO ARKANSAS. SHEAR SHOULD STILL BE FAVORABLE FOR SUBSTANTIAL UPDRAFT ROTATION ...WHICH WILL ENHANCE THE RISK FOR LARGE HAIL IN THE MOST VIGOROUS STORMS.

Hey, Venture, have there ever been a tornado in a snowstorm? A real tornado with snow falling? Is that ever possible?

There has, I would have to dig up the article. I know of a few cases, but some get a little complicated. Where it would be an elongated storm with snow on one end, and the tornado on the other. Really it just comes down to instability, moisture, and shear to get the setup to happen. I'll do some digging and see what I can find.

Quick update - storms are ongoing and developing northward today. Marginal risk of hail with these storms, but nothing horrible.

Not a tornado, just a "snow-devil"...but this is cool. YouTube - Snow Devil / Twister at Jackson Hole, Wyoming (http://www.youtube.com/watch?v=45XJwlweRNQ&feature=related)

Venture, what storms? Are you saying that the energy is now tracking to the north of us rather than hitting us head on?

Venture, what storms? Are you saying that the energy is now tracking to the north of us rather than hitting us head on?

No, he's saying that there are storms down in Texas that are building/developing northward. Nothing on the scale of Monday, just some rain basically...

So, what are we lookin' at as far as snow? The lines on the map in the other thread were kinda all bunched... anywhere from 1 inch to 4 inches?

I would say...2-5" is pretty good estimate right now, but the effect of ground temps (melting) and snow compacting (heavy wet snow) will influence those numbers. There could be 5 inches worth of snow that falls, but only an inch is actually on the ground. Snow fall forecasts are typically going to be pretty inaccurate more than 12-24 hours out unless you have a boring, typical setup (cold ground, winter, no difference in temps going up, etc).

Here is what the NFO is saying...

http://kocoweatherblog.files.wordpress.com/2009/03/snow.jpg?w=426&h=287

I'm wanting to throw some grass seed down in my yard real soon. Is this the kind of moisture that will be good for that? (slow and steady so it won't all wash down the street. The snow may even help keep it in my yard).

Most of our attention today has been devoted to the upcoming storm
system progged for friday. The approaching s/w trough may be
identified on water vapor imagery touching off some lightning in
id/mt/wy. 12 utc model runs from today show somewhat of a more
southerly track than previous runs...moving the surface low along or
south of the red river.nam/ukmet are considerably slower than the
gfs...and with such an intense and deepening low this solution is
not out of the question. With more than sufficient instability and
shear...among other ingredients...the environment in southeast
oklahoma and back into western north texas could be favorable for
severe thunderstorms as early as thursday afternoon. If the low
tracks more southerly...better moisture may remain further south in
texas. A more northerly track would mean larger coverage of severe
storms...but could also keep accumulating snow further to the north.
The winter storm watch was expanded a little further south and east
to cover areas where greater snow accumulation is expected on friday
into saturday...based on a low track further south. With high wind
speeds...blowing snow reducing visibility especially in northwest ok
may be a concern and this has been added to the forecast.

Guess I'd better bring the strawberry pots in...and find some way to cover my parsley. Looks like mom was right--don't plant ANYTHING until after April 15.

Major March Snow on the Way
Posted on March 25, 2009 by Jonathan Conder

I hope you are ready for some good old March Snow, because it is on the way. A Upper Level Low currently over British Columbia, is on a bee line for Oklahoma and it is going to bring cold air and heavy precipitation. This looks like the biggest snowfall I have ever forecasted for Oklahoma in the last 5 years. I am not ready quite yet to hang my hat on snowfall amounts, but I would not be surprised if parts of Northwestern Oklahoma pick up over a foot of snow. Yes, I said it, a Foot! I also think OKC will pick up measurable snowfall, but the big question is what time will the rain change over to snow on Friday? That will make all the difference in the accumulations in the metro.

So, get out today and enjoy the lighter winds in the metro with highs in the lower 60s. Tomorrow is not bad either, with highs in the mid 60s. Rain is likely to begin in OKC very early Friday morning and changing over to snow during the day. It should continue to snow through Midday Saturday.

Again, I am not ready to put out an exact snowfall forecast, but this will give you an idea where I think the heaviest snowfall will occur:


http://4warnstormteam.files.wordpress.com/2009/03/blog_03202509.jpg?w=468&h=315

http://www.srh.noaa.gov/rtimages/oun/fxc_Snowfall_Totals.jpg?timestamp=1238018048

Sure hope we see some good snow in OKC. Been a long time since we've seen it without all the ice. I'm keeping my fingers crossed, but not getting too hyped about it. I've seen too many close calls where it looked great for getting snow, and we ended up getting all rain.

Also, this is a great thread, please keep it updated!!

http://kocoweatherblog.files.wordpress.com/2009/03/graphic33.jpg?w=426&h=287

We will not make any changes this evening to the winter storm
watch. 00z nam is just arriving. This system still has potential
to be a particularly significant and disruptive heavy snow event
for parts of the area... Especially for so late in the season. Nam
and gfs have been sticking to their guns with run-total snowfall
in the range of 20+ inches in parts of nw ok and adjacent ks/tx -
which is hard to believe at any time of the year much less the
first week of spring. 00z nam has double-digit totals into extreme
nw ok by mid-evening friday... 15-20 inches into harper county by
09z sat... And again dumps an extraordinary 30+ inches in sw ks.
This run-to-run and model-to-model consistency is leading to
increasing concern that this snow event will be one for the
ages... And that we need to ramp it up further with what amounts
to a "pds" winter storm watch. Updated wsw will trend that way
and should be out by 10 pm. Strong winds and related blowing/drifting
easily could make this one of the most crippling s-plains
snowstorms in recent history... Although current indications are
that wind speeds are unlikely to attain blizzard criteria. All
users are urged to take this developing situation seriously and
prepare as well as possible for what may end up being essentially
an unprecedented late-season heavy snow event in nw ok. 24

The north side of Austin got hammered by storms today, Marble Falls got so much hail it closed US 281 through there. Other parts had up to baseball size hail, lucky we got out of that side of town before it hit at evening rush hour.

Y'all be careful and stay warm.

Still looking the same for OKC?

New model runs are still in process. I'll be posting my thoughts and precip forecast after I see all those. This will probably be around Midnight when the run is complete.

4 hours past midnite. Anything?

I've just noticed that KFOR is putting us on the lite side.

We will upgrade the winter storm watch to a warning for our far
northwest counties... Beginning at 7 am tomorrow... Due to the
relative certainty of that area receiving winter storm quantities
of snow. There is still too much uncertainty elsewhere to upgrade
at this time. We also will add a row or two of counties to the
southern edge of the watch area from 7 am friday through 1 pm on
saturday.

The surface low will track east into the arklatex region by friday
evening... While the upper low moves into the area just south of
the texas panhandle. Cold air will continue to deepen across
oklahoma and western north texas... As the precipitation changes
from rain... To sleet... To snow across about the western 2/3 of
oklahoma and western north texas. There is also a possibility of
freezing rain or drizzle across parts of central oklahoma... If
surface temperatures fall faster than expected.

Any snow that falls on friday will be blown around by strong north
winds. Wind speeds look like they will remain below blizzard
strength... But this will need to be watched as newer model data
arrive.

Snow should begin to taper off friday night and end during the day
on saturday. Storm totals will likely exceed a foot somewhere in
the northwest half of oklahoma... But it is still far too early to
pinpoint the location. Convective snow bands will be possible...
Which may leave narrow bands of much heavier snowfall... Compared
with the overall snow field.


http://www.srh.noaa.gov/rtimages/oun/fxc_Snowfall_Totals.jpg?timestamp=1238048136

What the % of this system tracking a lil more south than predicted right now?

Looks like 4 is downplaying it some now. 1-3 in OKC. I wouldn't be surprised we get a dusting at most.

That's just sad they don't want to deliver the excitement. I'm hoping for serious nonstop huge and heavy snow for hours. It won't be that bad, especially when all of it will be gone the next day or two.

Goin crazy here! Weather this eventful, I expect constant updates. lol KOCO haven't update their blog all night and it is well thru the morning hours and still no update.

Maybe they're backtracking, kfor hasn't updated their blog either. Expect they should know by 430 the path the storm will take, also, there's the risk of severe storms today, so they have quite a bit going on.

Would be quite funny with all the hype, if it turns out to go way farther north.

Heres the latest snowfall forecasts I could find, they are two different models so they're a little different. Just click on the area (blue dot) you want to see.

http://wxcaster.com/gis-snow-overlays.htm

http://wxcaster.com/gis-gfs-snow-overlays.htm

I'm assuming thats from the GFS? Think the NWS is leaning toward ECMF, which has more accumulations.

KOCO haven't update their blog all night and it is well thru the morning hours and still no update.

For all the hype of being on alert and having crews in place, blogging etc. they sure are quiet. I think the data must of changed, and they are trying to figure out how to back track. Sure the NW will get quite a bit of snow, but for the metro with all the talk of the snow plows and crews getting ready, it makes them look silly. You would think they would learn from their past mistakes.

KFOR got an online blog?!

They finally got a blog!!!

4Warn Storm Team @ KFOR-TV (http://4warnstormteam.wordpress.com)

They are in desperate need to clear up their header logo!

http://4warnstormteam.files.wordpress.com/2009/03/blog_03202609.jpg?w=468&h=315

Models lat night were definitely keeping most of the snow out of OKC. Got a bit too tied up to post anything last night.

Im dreaming of a white christm*&*%& Wait a minute, whats sad is my wife and i boughta bunch of flowers at lowes last weekend :( this is going to confuse my little 4 year old, just two weeks ago she said look trees are green and we took her to lowes and she said spring flowers easters almost here, now when she wakes up saturday, she might ask us where is santa and the x-mas tree.. oklahoma weather is just crazy. I LOVE IT

The Winter Storm Warning has been expanded to the south and east to as close as Watonga. Can't seem to embed a video on here, couple big wigs from accuweather.com are predicting heaviest snow outside of the mts, to be between OKC and Wichita, 13-14 inches, one asked the other if he could get on a plane and go to where the heaviest snow would be outside of the mts, he said between okc and wichita.

I'm assuming thats from the GFS? Think the NWS is leaning toward ECMF, which has more accumulations.

ECMWF is highly restricted and only certain products are available to the public. WRF definitely keeps precip in the .3 to .6" range during most of the event, with temps warming again in the last 6 hours of it. So wouldn't be shocked if it is a mix to snow for a few hours and then back to rain at the end - essentially eliminating most of the accumulations for the metro. GFS pretty much same story, but may lean more towards a slower turn over and ending as snow instead of rebounding temps.

Either way...moisture to help get us caught up.

The Winter Storm Warning has been expanded to the south and east to as close as Watonga. Can't seem to embed a video on here, couple big wigs from accuweather.com are predicting heaviest snow outside of the mts, to be between OKC and Wichita, 13-14 inches, one asked the other if he could get on a plane and go to where the heaviest snow would be outside of the mts, he said between okc and wichita.

Everyone from Accuweather needs to be dumped in the ocean. That organization is the most worthless weather company in the world.

I think rain to snow, don't think it will go back to rain due to the fact that it's scheduled to end around noon sat, low close by will bring cold air with it, so think once it goes to snow it will stay snow. Was reading some info, and gfs is apparantely showing more of a southern track, and slowing down, if that's the case, it would put the metro in more of the heavy snow.

update from NWS as of noon.

http://www.srh.noaa.gov/rtimages/oun/fxc_Snowfall_Totals.jpg?timestamp=1238087000

either way, we are going to see the white stuff, which is great for me, im off weekends so i cn actually enjoy it while it last, i lean to what venture 79 is saying, ive seen it go back to rain before and everything melt away, so its a waiting game

I think rain to snow, don't think it will go back to rain due to the fact that it's scheduled to end around noon sat, low close by will bring cold air with it, so think once it goes to snow it will stay snow. Was reading some info, and gfs is apparantely showing more of a southern track, and slowing down, if that's the case, it would put the metro in more of the heavy snow.

Farther south track has the risk of cutting off moisture faster and limiting the heavy snow fall fall. So really, the risk for a heavy snow fall in OKC proper is going to be some what limited. Granted, I think 3-6 inches is just a nice quick snow fall and anything less is a dusting. Blame me for growing up where they get "real" snow. LOL

I think if it goes south it increases heavy snow here, the low has cold air with it, and its pulling moisture from the gulf, and if it slows down, it obviously will snow longer as it sits and spins. Severe weather may break out later today to our south too.

I just sent a long email to Jon congratulating him on getting the new weather blog started. Not only that, I sent him a list of suggestions that he can transform this blog into something much like KOCO's. Here is a partial email below.

.....

I need you to encourage Mike, David, and the others to use this blog as well. I know it will be tough to convince Mike to do this, but work your magic! This is a very important tool and it does have an impact, if used wisely.

The blog will need to be actively updated at least 1 to 3 times a day, more during eventful weather.

Be sure that comments are checked promptly and approved to keep conversations alive.

Find someone at the station, maybe someone in the web/internet dept to do LIVEBLOGGING, the same as KOCO does. That way, while the entire team is busy, someone will post constant raw on-the-spot updates every few minutes (we love this cuz we know everything before people watching on tv does lol). This person will listen in on everything from the weather dept, the newsroom, and constantly checking emails for reports from viewers to post. Check out KOCO's blog (in ur own spare time..not at the station..lol), so that you can see how it is done. When a person does LIVEBLOGGING, they make a post and then continue to edit that post with updates (new updates at top with time typed). This is also very useful for people having no access to tv and comp. They can access to the blog from their mobile phone to read it all. It's fun reading on a BlackBerry. lol

I hope I typed it all out clearly for you. :-)

This weather blog is also a helpful tool to educate. During slow days, you or someone else on the team (interns, too) can post anything to educate, a story, anything interesting. It doesn't always have to be bout the weather. :-)

I'm so used to KOCO's blog, so I hope you can make KFOR's exciting as well.

Thanks for reading! :-)

i cant see anywhere on the news intwenwt or weather nets, where it shows takinga southern direction, all i see is newsok says low friday night is 31 degreen then rebounds to mid 40s, kfor says 1-3 inches possible, that possible now.. so whats the deal where is 3-6 coming in at now?

I suggest anyone with any ideas for the new weather blog to email him. :-)

look at prior posts, there's pics.

NWS Norman, Oklahoma - Enhanced Weather Page (http://www.srh.noaa.gov/oun/enhanced.php?map=5)

looks like maybe 3 inches in okc and south metro,

This is a little out of our area, but I found it interesting. From the NWS Amarillo office:



"AN EXTREMELY DANGEROUS WINTER STORM IS EXPECTED TO IMPACT THE
PANHANDLES REGION BEGINNING LATE TONIGHT. COLD TEMPERATURES WILL
RETURN TO THE PANHANDLES TONIGHT...WITH PRECIPITATION BEGINNING AS
LIGHT RAIN BEFORE SWITCHING TO SNOW OVERNIGHT TONIGHT. BY EARLY
FRIDAY MORNING HEAVY SNOW AND VERY STRONG WINDS WILL BE AFFECTING A
LARGE PORTION OF THE AREA. NORTHERLY WINDS OF 35 TO 40 MPH WITH GUSTS
OVER 50 MPH WILL CAUSE WIDESPREAD BLOWING SNOW WITH NEAR ZERO
VISIBILITY IN WHITEOUT CONDITIONS FROM FRIDAY MORNING THROUGH FRIDAY
NIGHT. HEAVY SNOWFALL OF 6 TO 12 INCHES IS EXPECTED ACROSS THE
WARNING AREA WITH AMOUNTS IN EXCESS OF 12 INCHES COMMON. SNOW DRIFTS
OF 10 TO 20 FEET WILL BE POSSIBLE BEFORE THE SNOW FINALLY ENDS
SATURDAY MORNING.

THIS IS AN EXTREMELY DANGEROUS STORM. ANYONE CAUGHT OUTSIDE DURING
WHITEOUT CONDITIONS COULD BECOME DISORIENTED AND MAY NOT BE ABLE TO
FIND SHELTER. TRAVEL WILL BE DANGEROUS IF NOT IMPOSSIBLE ON
FRIDAY...WITH POWER OUTAGES POSSIBLY LASTING INTO THE WEEKEND."

I'm so jealous......10-20 foot drifts.

with those kinda drifts, i would be likea kid again and create my own cave or igloo

10 to 20 feet?!?!?!?!?! Is that a major typo?!

Addressing ongoing severe weather. Couple hail storms going through the Tulsa area right now. Mesoscale discussion (MCD) is now out for this area to cover the isolated hail events. Back by OKC, short term model guidance has very slim opportunities for severe weather here, keep it mostly east of I-35.

10-20 feet? It's the end of the world i tell ya!

Alright...here is my best guess right now. This will change as this evenings models roll out. Please keep in mind my forecast is actually for precip falling, not what you will see on the ground. A lot of things are going to come in play on ground/visible accumulations. 1) On going rain tonight tomorrow that will cause snow to melt on impact until cold enough. 2) 50+ degree ground temps will cause melting for first batch falling. 3) Some areas will see sleet/rain mixture during the event, which lowers ground totals.

So here it is...

http://www.flytol.com/coppermine/albums/userpics/10001/okla-snow-3262009.jpg

A couple of things of note recently.

The storm that just went south of Tulsa looks like it turned into a monster hailer, and possibly just had a wind event associated with it somewhere near Tahlequah. Also, the dryline or a dl bulge has entered SW Oklahoma, hope this doesn't cut off any moisture needed for snow. Also, on the NAM the last run had the snow a little farther south.

Yeah, I tried to go middle of the road with my snowfall forecast, but eh - i'll adjust it again tonight. I want to see what activity we get this afternoon and evening, and definitely the dryline is going to be a huge play. If moisture gets pushed out early down there that will setup the typical dry slot much earlier which is why I kept a lot of 1-3" totals on the south end, even in the watch area. I'm also a bit concerns how much the mid levels warm back up once the cold core passes through. Precip will still be ongoing as the core passes east, so that brings in the chance for sleet/rain/frz rain. Norman WFO is picking up on this as well in their zone forecasts showing only a brief change over to all snow here in Norman before going back to a rain mix Saturday.

I tend to find winter storms pretty fun to try to forecast out. So many more things can screw with snowfall totals. Then there is always the chance of convective development and wonderful thundersnow to develop and you just doubled your snow fall totals in a snow area.

Thunder....the 10'-20' was for "drifts" not accumulations. Heres a link to the AMA NWS presentation. NOAA's National Weather Service (http://www.srh.noaa.gov/ama/march2009_blizzard/)

New Day 1 Severe Outlook is out, northern Oklahoma removed, Central remains. New development is being watched for along the dryline in SW Oklahoma.

Portion of the discussion that matters...


A WINDOW OF OPPORTUNITY STILL APPEARS TO EXIST FOR
ISOLATED LATE AFTERNOON/EARLY EVENING SURFACE BASED STORM
DEVELOPMENT NEAR THE WARM FRONT/DRY LINE INTERSECTION ACROSS NORTH
CENTRAL TEXAS INTO SOUTH CENTRAL OKLAHOMA. IF THIS OCCURS...LATEST
SURFACE ANALYSIS SUGGESTS THAT BOUNDARY LAYER MOISTURE WILL BECOME
SUFFICIENT TO SUPPORT THE RISK FOR TORNADOES...IN AN ENVIRONMENT
OTHERWISE ALREADY SUPPORTIVE OF SUPERCELLS ALONG THE WARM FRONT
ACROSS THE RED RIVER VALLEY. AS THE PRIMARY SURFACE LOW MIGRATES
OUT OF THE HIGH PLAINS LATER THIS EVENING AND OVERNIGHT...SIMILAR
ADDITIONAL SURFACE OR NEAR SURFACE BASED SUPERCELL DEVELOPMENT MAY
CONTINUE ACROSS THE SAME GENERAL AREA ALONG THE RED RIVER.