General Weather Discussion - January/February 2015

[venture]

Watching radar it does appear the melting layer is starting to come down a decent amount now. Earlier model runs had change over around 3AM-ish. Looking at the HCA image for radar...definitely getting close to a change over if we can get some cooling in the lower 1000 or so feet.

[venture]

Looking at trends with temps / wet bulb / dewpoints...it looks like greatest chance for change over to snow is going to run just south of I-40 from Minco over to Norman. Right now mPING reports have snow in Weatherford already. Right now they are running about 4 degrees cooler on Temp/DP/Wet Bulb than Norman for example.

[Anonymous.]

This band just isn't moving. Amarillo is going to need snow blowers to get out of this one if this keeps up.

The system should have been diving south by now, but it keeps barely sliding E/NE - keeping this band directly over I40.


Hinton to El Reno should see change over to snow very soon, then OKC. Grassy surface accumulations likely if the band stays.

[Anonymous.]

Agreed, venture. Just south of OKC and west still looks like a good spot for snow accumulations, if the band sags south before dying out - lower atmosphere temp profile should be just about right.

[Anonymous.]

Snow change over approaching El Reno to Mustang in the next hour. OKC by 2:30am will likely be snow.

[venture]

Norman's air temp has been dropping at least 2 degrees an hour since about 10pm. We are down to 36 so far now and it seems areas that are around 34 or lower are in the snow. So definitely agree change over isn't far off if this trend continues.

[venture]

We are now moving over to a wet snow now in Norman. Heavy band of precip is starting to sink further south. This is starting to look like it could play out where areas from Norman and west could see some wet snow accumulation over the next few hours.

[venture]

Brief update. Just as anticipated, temps in Norman and west continue to drop. Norman is now below freezing, while most Oklahoma County locations are still around 36.

HRRR indicates precip over the Metro area should end by 8AM. Things will need to be watched south of I-40 for the snow / freezing rain mix that we'll have now.

[catch22]

Snowing at the airport. Still a mix of rain but the snow is taking over

[catch22]

Back to rain only at the airport.

[venture]

Starting to get a nice dusting in Norman now. Roads should remain fine though.

[Anonymous.]

Looks like NAM wasn't too far off, just slightly aggressive on temperatures becoming favorable for snow to reach surface.

Kind of a waste of an epic snowband. To put it simply, most everyone along I-40 would have close to 10 inches of snow if it had been a handful of degrees cooler.

Amarillo is shut down with up to 15 inches in some spots.

[Anonymous.]

Right now it looks like our next storm (Feb 1) will be rain. Models can't decide if it will be cold enough. Regardless, some beneficial moisture will be nice.

[Anonymous.]

Newest GFS for end of month/beginning of Feb storm is pretty intense. Very powerful storm as it looks right now.

[venture]

Newest GFS for end of month/beginning of Feb storm is pretty intense. Very powerful storm as it looks right now.

This has pretty well been the trend for the last week, but yesterday it appeared to have a hiccup for one or two runs taking the storm way south. Now it is bumped back up and the last 2-3 runs have it being heavy rain to snow. I'm sure things will keep bouncing around a bit, but it has been very consistent at least in having a storm system around the time frame in the general area.

[Anonymous.]

Yea the recent consistency of GFS is mind blowing. If it means anything for our next storm, we may be measuring snow in feet, not inches.

[OkieHornet]

with a disturbance 9 days out, where is its location today?

[venture]

Yea the recent consistency of GFS is mind blowing. If it means anything for our next storm, we may be measuring snow in feet, not inches.

I think that speaks volumes about the work everyone put in to the upgrades that went in a week ago.

[venture]

Looks like it has also went back the colder/snow solution it had for awhile with the 18Z run...

[venture]

with a disturbance 9 days out, where is its location today?

It isn't easy to pick out this specific piece of energy/storm system...but my best guess is that right now it is over northern Russia. However, it is going to be a combination of things. Around Jan 30th a low appears it will form off the California coast and dive ESE through Texas and then start to curve back NE to the east of us. There is also what appears to be an ejection of energy come from British Columbia starting around the 28th and getting here on the 31st where it combines with the low moving through Texas.

[OkieHornet]

that's a lot of moving parts, huh? sounds like all it takes is one part of that to wobble around in location or time for it to mess things up for good or bad.

[Anonymous.]

Early morning GFS depicts southern track of storm again. Dropping pretty much a foot of snow over the northern half of TX. Have to see what we got for 12Z.

[s00nr1]

GFS still sticking with a heavy precip solution for next weekend -- we shall see where the cold air is:

[venture]

Beauty of a storm shaping up for late next week/weekend and early following week. Same system we've been talking about for days now, but if the 12Z GFS verifies it would do wonders in helping with the drought and fire concerns going forward. Granted this will all change later today, but you know...

Onset of precip starts the evening of the 30th over Western OK. Looks like a rain/snow mix over many areas. This will spread over much of the state through Midnight going into the 31st with the primary precip type being rain. Cold front will enter the state starting around Noon on Saturday the 31st. Most precip will be liquid prior to then with the state getting some good amounts of water - heavier south. Moderate/heavy rain continues through Sunday morning as the front approaches I-44 around or just after noon. Behind the front heavy snow appears to be the rule. Full change over in OKC should take place between Noon and 6PM (yeah that is a big window right now). Snow should end by very early Monday morning just after midnight on the 2nd.

Liquid (melted down) totals look pretty great for the state. The metro could see over 1.5-2" of precip. Snowfall of course is a rough guess right now, but the Metro could see a quick 3-6" snowfall before it ends. One thing that will need to be watched of course is the speed of the cold air entering in. General rule of thumb is cold air typically moves in faster than what models predict. Right now it looks like we should be below freezing from 925 MB level (roughly 1000' up) by 11AM - this should start the change over to snow. Surface temps aren't expected to be below freezing until 6PM. The key thing here is the bulk of the heavy precip rolls in late Sunday morning when temps start falling. If the cold air gets in faster than expected - big time snow for more people. As predicted this morning...a good balance of heavy rain followed by heavy snow.

Either way...GFS has locked on to this thing for a significant time now. That says something.

Precip Forecasts...

[Tydude]

Channel 5 an 9 is giving this a 20 percent of rain on a week from Today high of 43.