January: Increasing Clouds/Rain & Warmer To End Month

[wxman57]

Canadian cold front arrives here by tomorrow morning. Good thing it's not very cold in western Canada now. Temps in Montana and Dakotas only in the single digits to teens behind the front. A few below-zero temps in Canada, but nothing particularly cold for this time of year. Light freeze possible here Friday morning. I suppose the weekend looks good for marathon activities. More sun on Saturday than Sunday. Lows near 40, highs in the mid to upper 50s.

Next front arrives next Tuesday. Not particularly cold, though. Latest GFS has us back into the 70s for highs the next weekend and no further freezes through at least the 27th. Cold air remains bottled up to our north (hopefully).

Here's a meteogram for Houston based on the latest GFS.

[srainhoutx]

One heck of a Winter Storm shaping up for the Chicagoland. That area has been in a snow drought all winter season. The 12Z NAM is suggesting 8-10 inch totals and lake effect snows as well. Also the NAM is coming in colder for our area with a deeper trough. Winds are gusting to near 40 mph behind that Canadian front in Nebraska/South Dakota...

[redneckweather]

It seems to me that all the big forecasters are back pedaling on their strong talks of some butt whooping arctic air coming down later in the month. It also looks like the big shot hypster JB is even showing a bit less hype about it.

[wxman57]

06Z NAM and GFS had only about 3" snow in Chicago. Where do you see the 8-10" totals for Chicago? The twister snow accumulation chart has about 3-4" there. They have been fairly snow-free this winter.

[srainhoutx]

06Z NAM and GFS had only about 3" snow in Chicago. Where do you see the 8-10" totals for Chicago? The twister snow accumulation chart has about 3-4" there. They have been fairly snow-free this winter.
http://www.twisterdata.com/data/models/ ... URFACE.png

12Z NAM through hour 60...

[wxman57]

That's still only 4-5" of snow in Chicago, though. More of a nuisance than a major event for those folks. My wife is from Chicago, by the way. Her sister works for 911 in Woodstock - where they filmed Groundhog Day. Great movie. We went up there one July many years ago. I didn't even THINK to bring a jacket. Got down in the 40s during the day and I froze my butt off. Had to borrow a coat from my brother-in-law. Went out on their boat in one of the nearby lakes and I think I could have walked from one side of the lake to the other, stepping on different boats. It was that packed.

Sure thought they'd be getting a lot more snow this winter up there. JB still thinks the pattern is changing, but he's only talking of cold air for the northeast in the coming weeks.

[srainhoutx]

That's still only 4-5" of snow in Chicago, though. More of a nuisance than a major event for those folks. My wife is from Chicago, by the way. Her sister works for 911 in Woodstock - where they filmed Groundhog Day. Great movie. We went up there one July many years ago. I didn't even THINK to bring a jacket. Got down in the 40s during the day and I froze my butt off. Had to borrow a coat from my brother-in-law. Went out on their boat in one of the nearby lakes and I think I could have walked from one side of the lake to the other, stepping on different boats. It was that packed.

Sure thought they'd be getting a lot more snow this winter up there. JB still thinks the pattern is changing, but he's only talking of cold air for the northeast in the coming weeks.

LOT Updated Totals...

[wxman57]

Much will depend on the trajectory of the air across Lake Michigan. They're due for a little snow. Don't know if even 8" would cause too much of a problem, though. That's fairly common in winter up there.

Yeah, too bad JB's backing off on the big Arctic outbreak later this month. I'm all broken up about that...

[srainhoutx]

Much will depend on the trajectory of the air across Lake Michigan. They're due for a little snow. Don't know if even 8" would cause too much of a problem, though. That's fairly common in winter up there.

Yeah, too bad JB's backing off on the big Arctic outbreak later this month. I'm all broken up about that...

JB has flip flopped more time in the past 10 days than Carter has liver pills... Almost as much as DT has busted...

[srainhoutx]

Morning e-mail from Jeff:

Strong cold front will sweep across the region tonight with significantly colder temperatures for the end of the week. Light freezes likely both Friday and Saturday mornings across much of the area.

Upper air pattern is in the process of amplifying this morning with a cold Canadian air mass dropping southward down the plains. Prior to this front reaching SE TX, abundant sunshine and weak WSW low level flow will push afternoon highs today toward 70. Strong front will cross the region tonight with strong cold air advection in place all day Thursday. Highs will struggle to reach 50 degrees at most locations under strong NW winds of 20-30mph.

A very dry air mass with dewpoints into the lower 20’s for most locations will settle over the region Thursday night. Winds may not completely go calm and this may help mitigate the rapid temperature fall that would be normal on a clear and calm night. Even so, with dewpoints so low, feel most areas will fall below freezing and some locations could be below freezing for 4-8 hours. Since all locations have already froze this year and we are not looking at temperatures below 25 for more than 2 hours a freeze or hard freeze warning will not be issued. Most locations look to bottom out in the 26-30 degree range with lows in the 29-33 range within the urban heat cores. Could be colder on Saturday morning, but surface high begins to move eastward allowing a weak onshore component to the wind which will keep the overnight lows up some…still expect most locations to reach freezing again Saturday morning.

Warming trend starts on Saturday as surface high slides east allowing more sustain and uniform onshore flow to develop. Upper level flow becomes increasing SW over the weekend allowing Pacific moisture and upper level disturbance to impinge from the SW. Combination of weak disturbances aloft should help force a middle to lower TX coast trough, but the location and intensity of this trough will determine if rain chances need to be introduced and when. Current indications suggest that any rain chances will likely hold off until Sunday evening or even Monday at the earliest as the next upper level storm system approaches in the time frame. Plenty of time to watch and tweak rain chances and amounts for Sun-Mon as at some point it looks like widespread rains may impact the area again.

Note: The 4.06 inches of rainfall recorded on Monday at Hobby Airport as put this climate site 2.89 inches above normal for January, but the rainfall departure since October 2010 is still over 20.0 inches at this site. 4-6 inches of rainfall over the San Jacinto River watershed led to Lake Conroe rising .8 of a foot from Monday to today, but the lake is still over 6 feet below its normal conservation pool elevation. Extreme to exceptional drought conditions remain across much of the area, even with the recent rainfall events giving a testament of how severe and behind the rainfall deficits have become over the last 13 months. I will get a new update out on the drought by the end of the month.

[srainhoutx]

The 12Z GFS continues to advertise some light rain early next week as the U/L off the California Coast moves inland and E across the Southern Rockies. The GFS also suggests a coastal trough will develop and keep some moisture/clouds around as the mid next week front stalls and begins to wash out along or near the Coast. It is also noteworthy that the GFS continues to sniff a potent storm crossing the S Plains around the 25th with some 'colder' air lurking just to the N of Texas. While we do warm up and wxman57 will be happy, rain chances do continue throughout the long range with an active Pacific pattern and a zonal flow and some STJ action as well.

[srainhoutx]

The 12Z Euro is offering some hints regarding the longer range. The GFS has suggested a potent storm for several days around the 25th, +/- a couple of days. The long range Euro suggests that a noisy STJ is developing and just off the NW Pacific Coast, a trough is developing. The Bering Sea Ridge begins to press down, or roll/fold S of the Arctic Circle suggesting that very cold air the Canada may well begin to head S into the Western US. If a storm crosses the S Plains as the GFS is suggesting some chilly air may well be poised to spill further S and displace the Mid Continent Ridge and warmth toward the E. There are even 'hints' of a weak -NOA blocking near Greenland. We will see.

[wxman57]

12Z GFS is warmer (for us) than the 06Z. I think it's probably not cold enough for Friday's or Saturday's low here, as IAH could reach freezing both mornings. Quite a bit drier with next week's rather weak cold front, too. Euro says no front next Tuesday. Canadian brings a weaker front through on Wednesday.

[Andrew]

From looking at all models they continue to show lowering heights, increasing convection, and an overall drop in temperatures across Canada. Temperatures are about to drop in Canada and if we can get a less zonal progression we could see a lot of cold air filter south.

[wxman57]

From looking at all models they continue to show lowering heights, increasing convection, and an overall drop in temperatures across Canada. Temperatures are about to drop in Canada and if we can get a less zonal progression we could see a lot of cold air filter south.

That's the problem - the projected zonal flow. All the models indicate building cold air in Canada over the coming week, but all also keep it bottled up north of the U.S. for the most part. And the models indicate that the cold air in Canada fades by the end of the month. I need to get one cold day with a high of 44F for our January forecast contest. Currently, I'm in 3rd place because our coolest high has been 57. I pegged the January high of 78 (so far) and am pretty close to the warmest low (I have 66, was 64). And I have the "warmest" lowest temp for January of all in the contest (30), which is not looking too bad so far.

[Andrew]

From looking at all models they continue to show lowering heights, increasing convection, and an overall drop in temperatures across Canada. Temperatures are about to drop in Canada and if we can get a less zonal progression we could see a lot of cold air filter south.

That's the problem - the projected zonal flow. All the models indicate building cold air in Canada over the coming week, but all also keep it bottled up north of the U.S. for the most part. And the models indicate that the cold air in Canada fades by the end of the month. I need to get one cold day with a high of 44F for our January forecast contest. Currently, I'm in 3rd place because our coolest high has been 57. I pegged the January high of 78 (so far) and am pretty close to the warmest low (I have 66, was 64). And I have the "warmest" lowest temp for January of all in the contest (30), which is not looking too bad so far.

Yea models even through the lower resolution phases suggest that we will maintain that zonal flow but then again models have been back and forth a lot lately. Maybe during the end of the month/ the beginning of February we may see some cold air break off. Too soon to really tell though. I am interested to see how the SSW will affect the cold air up in Canada.

[srainhoutx]

From looking at all models they continue to show lowering heights, increasing convection, and an overall drop in temperatures across Canada. Temperatures are about to drop in Canada and if we can get a less zonal progression we could see a lot of cold air filter south.

As I posted yesterday, Dodge City, KS often provides some hints and the potential issues with Arctic boundaries and air masses and just how fickle guidance can be with any subtle changes. Yet today the Euro offered another hint and DDC mentions it in their afternoon update:

ANOTHER WARMING TREND IS EXPECTED BY JANUARY 18-19TH WITH HIGHS
POSSIBLY REACHING TO NEAR 70F IN A GENERALLY ZONAL MID TO UPPER-LEVEL
FLOW REGIME WITH LEE-TROUGHING AT LOW-LEVELS. HOWEVER, AS IS OFTEN
THE CASE IN ZONAL REGIMES, THERE WILL BE A SHARP TEMPERATURE
GRADIENT BETWEEN DOWNSLOPE FLOW OVER THE SOUTHERN AND CENTRAL PLAINS
AND ARCTIC AIR OVER THE NORTHERN PLAINS OR SOUTHERN CANADA. ANY
SHORTWAVE TROUGH TRAVERSING THE FLOW COULD RESULT IN ANOTHER SURGE
OF COLD AIR. THE ECMWF IS ADVERTISING ANOTHER SUCH COOLDOWN BY
JANUARY 20-21ST. NO SIGNIFICANT PRECIPITATION IS EXPECTED THROUGH
JANUARY 21ST.

[Andrew]

BTW the storms on Monday have been officially surveryed by the NWS and here are the results: An F1 struck in Fort bend briefly.

http://www.srh.noaa.gov/hgx/?n=jan9_2012_storms

[srainhoutx]

The cold front and very gusty winds with light snow falling in Pampa is making progress S and E. 32F in the N Panhandle while 80F in Laredo at this hour...

[Paul]

Steve , any idea when flight delays will happen in Chicago tomorrow...I have a 1 departure but a 100 percent chance of snow......


Paul