December Weather Discussion. Will We See Rain?

[wxman57]

My question is, if we do have a little moisture to work with, will it even be cold enough to produce some form of frozen precip? Man, I sure wish we had a pattern to work with like last fall/winter!

GFS does indicate some moisture now, but it's all below the freezing level. That would mean light rain. Euro looks too warm for anything but rain, too. Canadian is a bit colder. Frozen precip prospects still appear to be slim.

[srainhoutx]

For what it's worth, the 12Z GFS has come in a bit stronger with the strength of the short wave and does suggest some moisture and cloudiness over SE TX. Temps do not look conducive for anything of the freezing variety in our area, but there are some subtle differences now showing up in that model from what it was depicting. I'd say a chilly light rain and hope for an unexpected surprise of a possible ice pellet or two at this range.

[wxman57]

That's what I'm seeing, srain. Cold with some very light rain possible Tuesday night. Temps don't look cold enough for anything frozen. And, really, the GFS isn't forecasting any precip at all Tuesday evening. Can't rule out a few sleet pellets IF some colder air than is currently forecast slips in. Here's the latest GFS meteogram for IAH. Note the increasing temps over previous runs (warmer). This is not looking like a freezing/frozen precip event.

[srainhoutx]

The Canadian continues the colder trend and now suggests some possible flurries/sleet over parts of N TX. If that model were correct, clouds and light rain maybe mixing with some possible sleet pellets could not be ruled out for our area.

[srainhoutx]

The 12Z Euro suggests a bit stronger short wave perhaps and appears to be a bit 'cooler' as well.

[wxman57]

New Euro and Canadian are both dry for us with the passing disturbance. Canadian has trended away from any precip in the area with a high center not far to our NE. Temps are not indicated to be cold enough for any frozen precip. Sleet potential looks very low due to limited available moisture and lower-level temps that are well above freezing. Just looks like a reinforcing shot of cold air Tuesday with some clouds marking the passing of the disturbance.

Rule of Thumb: One general rule that we've found as far as getting precipitation here is that you can look at the pressure that the models are forecasting for our area. If the predicted surface pressure is 1024mb or greater, then no precip is likely. In this case, all the models are forecasting our surface pressure to be well above 1024mb Tuesday nigh/Wednesday morning. That would be a good indicator of no precip Tuesday night.

[redneckweather]

So what wxman is saying in redneck terms is.....SOL.

[srainhoutx]

Longer range Euro suggests a big dump of Arctic air mainly to our E, but some of the temps if verified would be brutal in the Ohio and Tennessee Valley Regions as well as the Upper Mid West with readings well below zero and some -20's near the Great Lakes. Brrrrr...

[biggerbyte]

Lol

It took 41 pages to get same old, same old?

Come on fellows. If that isn't enough to prove my point about model forecasting, I don't know what is.
Saturday or Sunday are still prime for that kind of thing.

I guess it gets exciting talking about it. Some folks who read these forums get their hopes up.
Reality sets in now over the next couple of days.

Oh well! I bet some of the newbies got weather wise today

AZ, fire off that magic gun... Turn things around...

[srainhoutx]

For what it's worth the 18Z GFS is suggesting a bit stronger disturbance crossing the area. HGX has 20% pops up and New Orleans is mentioning a wintry mix from this clipper like system.

[txsnowmaker]

Where is everybody?! Ch. 13 has Houston at 32 degrees Tuesday night/Wednesday morning and NWS has a 20 percent chance of precip Tuesday night...

[srainhoutx]

First surge of cold air taking shape to our N tonight. I suspect the 'night crew' will be watching carefully tonight...

[wxman57]

I don't think the temperature will be able to reach 32F Tuesday night with the clouds produced by the passing disturbance. Maybe 37-38 is more likely. 18Z GFS has slightly warmer temps than the 12Z, and no precip Tuesday night. Just doesn't look like much to get excited about. The colder air will be deeper farther east SE LA/southern MS than it will be here. 18Z forecast sounding for southern MS actually did indicate temps aloft cold enough for frozen precip, but the moisture there will be quite limited as well.

Best to just enjoy the warm temps tomorrow because the rest of the week will just be cold with only a slight chance of precip Tuesday night (rain).

[srainhoutx]

Looking at some of the meso data, I'm wondering if the clear skies will be rather short lived. That would suggest the GFS is too warm for our high temps. The Pacific feature appears to enough moisture and that would suggest a possible cirrus canopy to me. I guess we'll see.

HGX in afternoon discussion...

THE ECMWF HOLDS ONTO QUITE A BIT OF
MOISTURE AND DEVELOPS A BIT OF A COASTAL TROUGH AND BETTER LIFT.
SO IF THIS PANS OUT...FORECAST MAY NEED HIGHER POPS.

12042010 00Z NAM nam_500_060l.gif

12042010 00Z NAM nam_700_084l.gif

[TexasMetBlake]

I was listening to 'Dr. Jim' on Fox out in the livingroom and I heard him say he was reporting from the ice rink downtown at DG and that "we may have a little ice on our own." I think he is off target a little bit. lol

[txsnowmaker]

KHOU says 35 on Tuesday with 30% chance of precip.

[redneckweather]

I see that the NWS has me @ 31 degrees Tuesday night with a 20% of rain. It's gonna SNOW!!!!!!!!!!!!
























KIDDING KIDDING!

[srainhoutx]

The front is progressing S this morning a bit quicker than previously thought. Areas to the N could see a wind shift by mid day/early afternoon...

[wxman57]

One thing I'm becoming more confident in is that Tuesday night will at the very least be cloudy (overcast). That means temps Wednesday morning should be well above freezing here. It takes a mighty strong front to drop our temps below freezing without the aid of radiational cooling. All models are in fairly good agreement that the upper-level disturbance will move across southeast Texas on Tuesday night. That looks like a give, too.

And all models now are in good agreement that the cloud deck will be in an above-freezing airmass, with temps at the cloud bases about 38-45 degrees. GFS has the tops of the cloud deck in slightly sub-freezing air, but 80% of the clouds (lower part) are above freezing, and temps increase on the way to the ground. That looks reasonable, too. It just doesn't appear as though this airmass will be cold enough for freezing precip here, as I think our low on Wednesday morning will be in the 37(north) to 42(south) degree range.

One other thing that the models are agreeing on more is the presence of at least some moisture aloft, enough to produce light precipitation Tuesday night. Latest GFS meteogram indicates about .05" of rain. Canadian and Euro indicate some very light precip as well. Might not even be enough to wet the ground in most areas.

For those of you looking for some winter weather, I don't think that there is NO hope with this event. Snow seems quite unlikely, though. What I think we could see is a few very cold raindrops (more like drizzle) Tuesday night. Temps would be in the upper 30s to low 40s. But if the cold air aloft is a little lower and if the clouds are a little higher, up into the sub-freezing air, then we might be able to see a few sleet pellets. They'd melt upon reaching the ground, though.

Here's the latest GFS meteogram. Doesn't even show a freeze through the 12th. Could see near-freezing temps here Thursday morning, though.

[srainhoutx]

The 12Z NAM and WRF suggest a bit more amplified disturbance and a bit S of what guidance has suggested. That will probably change, but at least it's something to watch over the weekend.