January: Calmer Pattern To End The Month

[srainhoutx]

Another chilly morning here in NW Harris County where temperatures have dropped to the mid 30's. Those temperatures will rebound nicely today ahead of a re inforcing cold front arriving tonight with an even colder front arriving Thursday as a fast progressive NW flow remain the theme this week. The Marathon weather still looks nice for the runners, but yet another front may arrive late Sunday into Monday continuing the dry weather pattern.

Changes are beginning to show up in the longer range computer guidance suggesting that a broad trough will develop across North America as the Western Ridge breaks down and that pesky -EPO/-WPO regime becomes re established and a strong Ridge develops across the Gulf of Alaska and noses all the way into the interior of our 49th State. The deterministic and ensemble guidance are once again developing a pattern that looks very similar to what we witnessed beginning in mid last November and continued into early January. While it is likely that we have seen the 'coldest' air of our Winter Season, it certainly does not mean winter is over. If such a pattern does in fact does develop toward the end of January/early February, climatology suggests our greatest threats for wintry weather are just ahead as upper air disturbances ride S along or just W of the Inter Mountain West into the base of the trough tapping Gulf moisture allowing precip albeit somewhat light to develop across our Region and strengthen as those storm systems organize over Colorado/New Mexico/Texas and Oklahoma and turn NE. Enjoy the relative warm/dry weather while it lasts. Changes may well be lurking in about a 7-10 days.

01142013 00Z Euro 500mb Geopotential3250032hPa32and32Temperature32at3285032hPa_North32America_240.gif

01142014 00Z GFS 500mb gfs_z500_vort_namer_73.png

[wxman57]

Thanks very much for the update, wx. That temp spread works.

Actually for me, good running weather for a marathon is upper 30's at the start and 59 at the end, with mostly cloudy to cloudy skies so I don't get beat down by the sun.

Latest GFS has a low in the upper 40s Sunday morning, mid 50s by 9am (you'll be done by then, right?) and upper 60s by noon:

[Ounce]

Thanks very much for the update, wx. That temp spread works.

Actually for me, good running weather for a marathon is upper 30's at the start and 59 at the end, with mostly cloudy to cloudy skies so I don't get beat down by the sun.

Latest GFS has a low in the upper 40s Sunday morning, mid 50s by 9am (you'll be done by then, right?) and upper 60s by noon:

http://home.comcast.net/~cgh57/iahgfs12zjan14.gif

Thanks, WX. And yes, I'm done by 9, but I run another loop, so I can run in with the bulk of the runners. More satisfying, that way.

[wxman57]

Thanks, WX. And yes, I'm done by 9, but I run another loop, so I can run in with the bulk of the runners. More satisfying, that way.

You're doing a full marathon within 3 hours then running another loop? I only run if somebody much bigger is chasing me (and I don't have a weapon).

[srainhoutx]

The Climate Prediction Center has updated their Day 8-14 Outlook...looks like some colder air may return across our Region to end the month of January.

8-14 DAY OUTLOOK FOR JAN 22 - 28 2014

TODAY'S WEEK-2 OUTLOOK REFLECTS THE GROWING POSSIBILITY OF ONE OR MORE
SUBSTANTIAL COLD AIR OUTBREAKS ACROSS THE CONUS HEADING TOWARD THE END OF THE
MONTH. THE 500-HPA HEIGHT MANUAL BLEND REVEALS A HIGHLY AMPLIFIED PATTERN WITH
A MEAN RIDGE FORECAST JUST OFF THE WEST COAST EXTENDING NORTHWARD INTO EASTERN
ALASKA. DOWNSTREAM, A DEEP TROUGH IS FORECAST ACROSS THE EASTERN CONUS. THE
EVOLUTION OF THE FORECAST HEIGHT PATTERN OVER THE PAST FEW DAYS SUGGESTS THAT
THE SOURCE REGION FOR POST-FRONTAL AIR MASSES WILL BE GROWING COLDER AS
CROSS-POLAR FLOW BECOMES BETTER ESTABLISHED. TEMPERATURE PROBABILITIES MAY BE
TOO CONSERVATIVE AND GREATER PROBABILITIES FOR BELOW-NORMAL ARE LIKELY GOING TO
EXPAND OVER THE NEXT COUPLE OF FORECAST CYCLES. LATE IN THE PERIOD, COLDER AIR
MASSES ARE MORE LIKELY TO IMPACT PARTS OF THE NORTHERN ROCKIES AS WELL, WHERE
PROBABILITIES FOR ABOVE-NORMAL TEMPERATURES HAVE BEEN DRASTICALLY REDUCED FROM
YESTERDAY'S OUTLOOK.

TELECONNECTIONS UPON THE MAJOR HEIGHT ANOMALY CENTERS (WEST COAST, EASTERN
CONUS, NORTH ATLANTIC) SUGGEST THE FORECAST WAVE PATTERN MAY CONTAIN
WAVELENGTHS THAT ARE TOO LARGE GIVEN THE POTENTIAL AMPLITUDE OF THE PATTERN.
THIS INCREASES UNCERTAINTY, ESPECIALLY IN THE PRECIPITATION FORECAST, WHERE
SHORTWAVE AMPLIFICATION SEEMS LIKELY DURING THE WEEK-2 PERIOD, THOUGH IT'S
UNCERTAIN WHEN IT WILL OCCUR. CONFIDENCE IS FAIRLY HIGH THAT ANY AMPLIFICATION
WOULD OCCUR IN THE EASTERN HALF OF THE CONUS; NEAR-MEDIAN PRECIPITATION IS
FAVORED ALONG THE EAST COAST AS A RESULT. ABOVE-MEDIAN PRECIPITATION IS FAVORED
FROM THE CLIMATOLOGICALLY-DRY NORTHERN PLAINS, WHERE MULTIPLE SHORTWAVES
ENTERING THE MEAN TROUGH ARE LIKELY TO CAUSE SOME SNOWFALL, TO NEW ENGLAND,
WHERE ANY STORM TRACKS ARE FAVORED TO CONVERGE.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 15 PERCENT OF TODAY'S
OPERATIONAL 0Z GFS CENTERED ON DAY 11...15 PERCENT OF TODAY'S OPERATIONAL 6Z
GFS CENTERED ON DAY 11...15 PERCENT OF TODAY'S 0Z GFS ENSEMBLE MEAN CENTERED ON
DAY 11...15 PERCENT OF TODAY'S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 11...AND 40
PERCENT OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11.

FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: ABOVE AVERAGE, 4 OUT OF 5, DUE
TO GOOD AGREEMENT AMONG MODELS AND FORECAST TOOLS, OFFSET SLIGHTLY BY
UNCERTAINTY IN THE TEMPERATURE OUTLOOK ACROSS THE CENTRAL CONUS.

[ronyan]

CPC mentions the dreaded cross-polar flow...very cold in Siberia this time of year (Oymyakon -59F). Joe Bastardi was tweeting about how this was the coldest run for days 10-15 of ECMWF ensembles that he's ever seen.

[Katdaddy]

Temps in the 40s this morning will rise into the upper 50s under sunny skies. Nice weather to continue through Saturday. Race day still looks to have some fog and showers possible with morning temps in the upper 40s.

[srainhoutx]

Moring e-mail from Jeff:

Little to no change in the upper air pattern with a trough over the eastern US and ridge of high pressure over the western US with TX on the western edge of the eastern US trough.

Short waves dropping through the mean trough will continue to bring cold fronts across TX about every 48 hours…with one having passed the region overnight and another expected Thursday night. No moisture to speak of with NW flow aloft and Gulf of Mexico shut off so these fronts will pass through the region dry. Only impact will be an increase in wind speeds behind each front and a quick 24 hour cool down. Highs today will run about 10-12 degrees colder than yesterday and lows tonight will fall into the mid 30’s. Expect a similar result on Thursday night with the front with highs in the 50’s on Friday and lows in the 30’s Saturday morning. Looks like there will be some 50-60mph winds across the plains Thursday with that front which may aloft dust and send it south and east for a hint of haze in the sky on Friday.

For the weekend old frontal boundary will begin to return northward as a warm front on Sunday, but do not expect much more than an increase in sky cover on Sunday with any drizzle and light rain remaining south of the area. Lows will start in the 40’s and warm to near 60 by noon on Sunday with afternoon highs near 70.

Upper pattern appears to undergo some changes next week with the potential for slightly better rain chances and some colder air being brought into the region with best rain chances looking to be after the mid week period.

Fire Weather:

Dry fronts with low dewpoints and gusty NW winds will bring elevated fire weather conditions today and again Friday/Saturday. Does not look like we will be meeting Red Flag criteria, but with grasses currently cured from the recent freezes and fine fuels dry the potential for rapidly spreading grass fires is moderate to high. Highest risks is in and around the Matagorda Bay region where KBDI values range from 400-500 and rainfall has been light over the past 30 days.

[srainhoutx]

Looking toward the next week time frame and toward the end of January, the teleconnection indices continue to advertise a -EPO nearing the 3 to 3.5 range with a slightly negative WPO. The deterministic 06Z GFS as well as the 00Z Euro are suggesting a very stout Gulf of Alaska Ridge nosing well N into the Arctic Circle with abundant short wave energy dropping S from Canada. The trend the past couples of cycles has been to shift the colder air a bit further W. It will be interesting to see if the guidance continues this trend over the next 5-7 days. What raises an eyebrow is a noisy sub tropical jet that appears to be developing after the cold air arrives. The pattern does appear to be changing to a somewhat similar setup we saw back in late November/early to mid December where the trough axis was to our W and upper lows meandered near Southern California/Arizona as over running precip developed with cold air at the surface. We will see.

[jasons2k]

Stay away, Jack Frost. I've had enough of you this season and you've already done enough damage, thank you.

My yard looks like a war zone, but I think I managed to save my tender palms after several hours of prep work. I'm really not interested in climbing up-and-down ladders again any time soon, but I left the lights wrapped around them just in case.

[Ounce]

Y'all, thanks for the Sunday morning updates. With Jeff mentioning the warm front, at least now I understand how the temps will be rising so much with a mostly cloudy sky.

I guess if the warm front slows, it won't warm up as fast?

And WX, I wish I could run a 2 hour marathon, then I could make running my job, especially at my age.

[wxman57]

New meteogram for Houston. Latest is for temps in the low 50s at the marathon start, upper 50s by 9am and upper 60s by noon. Probably too warm for hard-core runners. I prefer running in temps above 80 degrees.



Extended-range meteogram indicates near freezing temps around the 28th. No major cold indicated, however.

[srainhoutx]

The Climate Prediction Center Day 8-14 Outlook offers some insight as to the upcoming extended range forecast and what the actual sensible weather may be across our Region as we end January and begin February.

8-14 DAY OUTLOOK FOR JAN 23 - 29 2014

THE WEEK-2 OUTLOOK REMAINS LARGELY UNCHANGED FROM YESTERDAY, WITH GROWING
PROBABILITIES FOR BELOW-NORMAL TEMPERATURES ACROSS MUCH OF THE CENTRAL AND
EASTERN CONUS. THE OFFICIAL 500-HPA HEIGHT MANUAL BLEND DEPICTS AN EXPECTED
SUBTLE RETROGRESSION WHEN COMPARED WITH BOTH THE 6-10 DAY OUTLOOK AND
YESTERDAY'S WEEK-2 OUTLOOK. THE GFS AND ECMWF SYSTEMS DIVERGE IN SOME NUANCED
DETAILS OF THE OUTLOOK, HOWEVER, WITH THE GFS FAVORING COLDER TEMPERATURES
ACROSS THE NORTHERN PLAINS THAN THE ECMWF. THIS IS INTRIGUING SINCE BOTH
ENSEMBLE MEANS ARE NEARLY IDENTICAL. TELECONNECTIONS UPON THE HIGH AMPLITUDE
POSITIVE HEIGHT ANOMALY FORECAST OVER THE ALASKAN PANHANDLE FAVORS THE GFS
SOLUTION, AND SO TODAY'S MANUAL SURFACE OUTLOOK REFLECTS MORE OF THE GFS
SOLUTION ACROSS THE NORTHERN PLAINS AND NORTHERN ROCKIES. ADDITIONALLY, THERE
HAS BEEN REASONABLY GOOD RUN-TO-RUN CONSISTENCY AMONG RECENT DETERMINISTIC RUNS
OF THE GFS, ALL OF WHICH SUGGEST A COLDER SOLUTION ACROSS THE CENTRAL CONUS,
NORTHERN PLAINS, AND NORTHERN ROCKIES. THE LOWER AMPLITUDE CANADIAN ENSEMBLE,
HOWEVER, FAVORS THE ECMWF SOLUTION.

THE PRECIPITATION OUTLOOK ALONG THE EAST COAST REMAINS UNCERTAIN. DESPITE
DRIER-THAN-MEDIAN SIGNALS FROM THE ENSEMBLE SYSTEMS, NEAR-MEDIAN PRECIPITATION
IS FAVORED BASED ON THE TELECONNECTIONS AND ANALOGS. ESSENTIALLY, THIS SOLUTION
HEDGES TOWARD THE IDEA THAT THE FORECAST WAVELENGTHS ARE PROBABLY TOO LONG
BASED ON THE FORECAST AMPLITUDE OF THE RIDGE UPSTREAM JUST OFF THE WEST COAST.
THE TELECONNECTIONS AND ANALOGS ARE MORE REALISTIC IN THIS REGARD AND HAVE
ADDED SUPPORT FROM VARIOUS RUNS OF THE DETERMINISTIC GFS.

THE LATEST DYNAMICAL MODELS ARE COMING INTO BETTER AGREEMENT ON THE DEVELOPMENT
OF AN INTENSE CONVECTIVE ANOMALY MOVING EASTWARD TOWARD THE DATE LINE IN THE
EQUATORIAL PACIFIC. THIS COULD FAVOR ENHANCED ODDS OF COLD AIR OUTBREAKS TOWARD
THE END OF THE WEEK-2 PERIOD AND BEYOND, CENTERED OVER THE CENTRAL CONUS.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 15 PERCENT OF TODAY'S
OPERATIONAL 0Z GFS CENTERED ON DAY 11...5 PERCENT OF TODAY'S OPERATIONAL 6Z GFS
CENTERED ON DAY 11...15 PERCENT OF TODAY'S 0Z GFS ENSEMBLE MEAN CENTERED ON DAY
11...20 PERCENT OF TODAY'S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 11...AND 45
PERCENT OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11.

FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: ABOVE AVERAGE, 4 OUT OF 5, DUE
TO GOOD AGREEMENT AMONG MODELS AND FORECAST TOOLS, OFFSET SLIGHTLY BY
UNCERTAINTY IN THE TEMPERATURE OUTLOOK ACROSS THE CENTRAL AND NORTHERN CONUS,
AS WELL AS THE PRECIPITATION OUTLOOK ALONG THE EAST COAST.

[jasons2k]

Here is a tidbit from this afternoon's AFD. Not good news for us. The trees up here are STILL under stress and if this continues, looks like another depressing summer.

CLIMATE...
DROUGHT CONDITIONS ARE BEGINNING TO CREEP INTO SE TX. SINCE
NOVEMBER 1ST...RAINFALL DEFICITS ARE BETWEEN 4 AND 8 INCHES WITH
THE DRIER CONDS TOWARD THE COAST. AREA RESERVOIRS ARE NEAR
CAPACITY WHICH IS GOOD NEWS. THE SEASONAL DROUGHT OUTLOOK WILL BE
ISSUED TOMORROW. HERE ARE A FEW OF THE LARGER RAINFALL DEFICITS
SINCE NOV 1ST:

SITE RAINFALL DEFICIT

LAKE JACKSON -7.68
HOUSTON HOBBY -5.38
NWS LEAGUE CITY -6.24
GALVESTON -5.87
HOUSTON BUSH -4.61
SUGAR LAND -4.73

[Ptarmigan]

Here is a tidbit from this afternoon's AFD. Not good news for us. The trees up here are STILL under stress and if this continues, looks like another depressing summer.

CLIMATE...
DROUGHT CONDITIONS ARE BEGINNING TO CREEP INTO SE TX. SINCE
NOVEMBER 1ST...RAINFALL DEFICITS ARE BETWEEN 4 AND 8 INCHES WITH
THE DRIER CONDS TOWARD THE COAST. AREA RESERVOIRS ARE NEAR
CAPACITY WHICH IS GOOD NEWS. THE SEASONAL DROUGHT OUTLOOK WILL BE
ISSUED TOMORROW. HERE ARE A FEW OF THE LARGER RAINFALL DEFICITS
SINCE NOV 1ST:

SITE RAINFALL DEFICIT

LAKE JACKSON -7.68
HOUSTON HOBBY -5.38
NWS LEAGUE CITY -6.24
GALVESTON -5.87
HOUSTON BUSH -4.61
SUGAR LAND -4.73

That is very concerning.

[Ounce]

New meteogram for Houston. Latest is for temps in the low 50s at the marathon start, upper 50s by 9am and upper 60s by noon. Probably too warm for hard-core runners. I prefer running in temps above 80 degrees.



Extended-range meteogram indicates near freezing temps around the 28th. No major cold indicated, however.

Thanks again for today's GFS. As far as running, you just have to be a little faster than the slowest person!

[Katdaddy]

Beautiful weather to continue through Sunday. A little chilly this morning with temps mostly in the 30s with a few 40s. Highs to should reach the mid to upper 60s under sunny skies today. Race day is looking better as fog and slight rain chances have been removed from the forecast with temps near 50F for the start.

Daily Historical Weather for January 16

Frigid temperatures filtered into Southeast Texas on this date in 1888. The temperature dropped to 23 degrees in Galveston. The high temperature at Galveston only warmed to 32 degrees with a few snow flurries reported.

[cristina6871]

so what do these models and long range forecasts mean for us who enjoy the cold weather? The last post I read dealing with the long range forecast seem to indicate we wouldn't get anything when the next break hits.

[srainhoutx]

so what do these models and long range forecasts mean for us who enjoy the cold weather? The last post I read dealing with the long range forecast seem to indicate we wouldn't get anything when the next break hits.

Well it is another frosty morning here in NW Harris County and we never made it past the upper 50's yesterday. Another re enforcing shot of colder air arrives this evening. The longer range indications as we head toward the end of January into February do suggest some colder air arrives as a cross Polar flow develops and brings some very chilly air across the N Pole from Siberia into North America. Are we going to see record breaking cold like we had a week ago? Probably not. What is interesting is there are increasing indications that our pesky sub tropical jet with increasing moisture from the Pacific will arrive late month and into early February. I'll be happy to send my natural gas bill for the past month to any that would like to 'pay for' all this cold weather.

[jasons2k]

I'm starting to wonder if the "cool shelf water" theory is being overblown a bit. I'm sure it is an influence, but I think the upper dynamics & other factors at play probably have a much greater influence. JMHO based on many years of observing Texas spring storm seasons.