February-Comfortable Days/Cool Nights To The Month

[srainhoutx]

The ensemble guidance remains in agreement that general Eastern trough with embedded short wave (Clipper system) will move across Canada along the Polar Jet and ridging controls the West in the short range.

As we head toward the medium range, changes begin to develop across the West as the upper ridge breaks down across the Great Basin and shifts E into the Mid West. Rich Pacific moisture begins streaming E from the EPAC and the sub tropical jet become active. A series of 500mb short waves dive S and meander over the NW Mexico/Arizona/Southern California Regions while a series of disturbances rotate under the base of a developing trough to our W and slide ENE providing clouds and perhaps some light rain chances early next week.

As the trough to our West deepens, a general unsettled pattern develops across New Mexico into Texas as pressures fall and an increasing onshore Gulf flow becomes established. During the later half of next week the ensembles are in rather good agreement that a strong storm system will drop SSE from the Gulf of Alaska. This storm appears to have some colder air associated with it as it pulls Canadian air into the Great Basin. There are indications that a potent Winter Storm will begin to slowly develop and eject ENE along the southern stream and a clipper system rides ESE along a stagnant Polar jet across the Great Lakes into the NE. Heights falls across Alaska and a PNA Ridge develops off the Pacific NW flooding Western Canada with ‘warmer air’ while the meandering somewhat cold core upper low is energized by the noisy STJ. The time frame that is of concern would be near February 8th, +/- a couple of days. This is a complex and complicated forecast due to the influence of the MJO, a Kelvin Wave as well as a changing pattern across the N Pacific. As has been mentioned, there are indications that some chilly Canadian air will be dropping S in the mid February time frame. The $64,000 question is will there be a noisy southern stream overhead during the time that colder air arrives. We will see.

EXTENDED FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER COLLEGE PARK MD
100 AM EST FRI FEB 01 2013

VALID 12Z MON FEB 04 2013 - 12Z FRI FEB 08 2013

MUCH OF THE UPCOMING CHANGES IN NORTH AMERICA HAVE BEEN PREDICATED
ON THE EROSION/BREAKDOWN OF THE UPPER-LEVEL RIDGE PLANTED ACROSS
THE ALASKA PANHANDLE AND SOUTHERN CANADIAN ROCKIES. THE 12Z MODEL
PACKAGE WAS IN DECENT AGREEMENT ALOFT WITH THE AMPLIFYING PATTERN
ALONG THE WEST COAST...AND AN UPPER-LEVEL RIDGE MIGRATING
DOWNSTREAM INTO THE CENTRAL PLAINS ON DAY 7. EAST OF THE
MISSISSIPPI VALLEY...CONFLUENT WESTERLY TO NORTHWESTERLY
UPPER-LEVEL FLOW SETS UP ALONG THE SOUTHERN EDGES OF THE UPPER
TROUGH AND ARCTIC AIRMASS ANCHORED ACROSS EASTERN CANADA...THE
NORTHEAST AND THE MID ATLANTIC STATES.

FROM WEST TO EAST...

IN THE WEST AND ACROSS THE PLAINS...
MEDIUM RANGE FORECAST TRANSITIONS ON DAY 5...WITH WEST COAST RIDGE
BREAKDOWN AND A SERIES A SHORTWAVES AMPLIFYING A DEEP AND COLD
TROUGH ACROSS THE INTERMOUNTAIN WEST...GREAT BASIN AND 4 CORNERS
ON DAYS 6-7. DOWNSTREAM...THE SOUTHWESTERLY FLOW ALOFT...WHICH
PRECEDES THE PACIFIC FRONT AND MIGRATORY H5 AXIS GENERATES
CONSIDERABLE CLOUDINESS AND THE RISK OF HIGH-ELEVATION RAIN AND
SNOW OVER THE HIGHER TERRAIN OF THE GREAT BASIN...SIERRA...FOUR
CORNERS AND NORTHERN ROCKIES. FURTHER DOWNSTREAM...IN THE NORTHERN
AND CENTRAL PLAINS...A DEEPENING LEE SIDE TROUGH WITH MULTIPLE LOW
CENTERS EMERGE WITH SHORTWAVE ENERGY EJECTING THE FRONT RANGE OF
THE ROCKIES. HERE...THE DETAILS ARE FAR FROM CLEAR. THE LEAD
WAVE...A BROAD WARM FRONT INITIALLY...BRINGS A RAPID WARMUP TO THE
SOUTHERN HIGH PLAINS...AND WILL CARVE OUT THE FRIGID ARCTIC
AIRMASS FROM SW TO NE...BUT NOT BEFORE THE MID-LEVEL WARM
ADVECTION HAS THE OPPORTUNITY TO PRODUCES SOME LIGHT FREEZING AND
FROZEN PRECIPITATION. ON THE SURFACE GRAPHICS...HAVE THE MID-LEVEL
WAVE MIGRATING EASTWARD INTO THE UPPER MS VALLEY AND GREAT LAKES
BETWEEN DAY 5-6...AND INTO THE ST LAWRENCE VALLEY BY DAY 7.

ACROSS THE GREAT LAKES AND NORTHEAST...
THE CONFLUENT FLOW ALOFT WILL KEEP THE MODIFIED ARCTIC AIRMASS IN
PLACE THROUGH DAY 5...WITH A SERIES OF WEAK MID-LEVEL WAVES...NOT
NECESSARILY ALL TO BE ALBERTA CLIPPERS...TRACKING ATOP THE ARCTIC
AIRMASS AND OUT INTO THE WESTERN ATLANTIC. PARTICULARLY...ALONG
THE WESTERN LAKE SHORES...TEMPERATURES SHOULD BE SLOWLY MODIFYING
UPWARD...WITH A GENERAL WARMUP EXPECTED BY DAY 6 ACROSS MUCH OF
THE MIDWEST...GREAT LAKES...AND OHIO VALLEY. MAINE AND NORTHERN
NEW ENGLAND WILL BE THE LAST PLACES WHERE TEMPERATURES WILL
MODIFY...AND BY DAY 6...MID-LEVEL WARM ADVECTION APPROACHING FROM
THE SOUTHWEST WILL LIKELY GENERATE LIGHT FREEZING AND FROZEN
PRECIPITATION.

SOUTHEAST AND MID ATLANTIC STATES...
SURFACE GRAPHICS CARRY TWO FRONTAL PASSAGES ACROSS THE
MID-ATLANTIC STATES...CAROLINAS AND SOUTHEAST THIS PERIOD...(ON
DAY 3 AND DAY 5) WITH A 3RD FRONT ON THE DOORSTEP (APPROACHING THE
APPALACHIANS) ON DAY 7. ESPECIALLY...SOUTH OF 36N-37N
LATITUDE...THE TEMPERATURE FORECAST WILL BE UP AND DOWN...WITH
WARM ADVECTION...PERIODS OF CONVECTION...SHOWERS AND SOUTHERLY
FLOW REPLACED BY NORTHWEST AND NORTHERLY FLOW AND COLD ADVECTION.
THE CHALLENGING PORTION OF THE FORECAST WILL BE ACROSS THE
CAROLINAS...VIRGINIA...THE DELMARVA AND BLUE RIDGE AND SMOKIES.
HERE...THE CONFLUENT FLOW ALOFT WILL ALLOW THE SHARP TRANSITION
ZONE...WITH TEMPERATURES IN THE 30S BENEATH IT...AND 20S TO ITS
NORTH AND 40S TO ITS SOUTH. BOTH THE GFS/ECMWF OPERATIONALS CARRY
SEVERAL NORTHERN STREAM WAVES ACROSS THIS TRANSITION ZONE AT THE
SURFACE AND SHEAR ZONE ALOFT.

VOJTESAK


00Z Euro Ensembles:

The attachment 02012013 00Z Euro Ensembles 00zECMWFENS500mbHeightAnomalyNA216.gif is no longer available

06Z GEFS:

The attachment 02012013 06Z GEFS 06zgfsensembles500mbHeightAnomalyNA216.gif is no longer available

[cristina99]

so what does this mean? Is this the new conversation thread about dreams of a cold mid-February?! I could use a few more days of cold!

[srainhoutx]

A pleasant warm weekend is on tap for our Region as a NW aloft continues and a couple of weak boundaries or back door fronts move in and quickly wash out as a deep trough over the East continue to drop Clipper systems into the Great Lakes and the Mid Atlantic/NE.

Changes begin to appear late Sunday as a weak short wave traverses the Region with increasing clouds and a slight chance of showers late Monday into early Tuesday. Meanwhile to our West, the upper Ridge will break down and a series of short wave disturbance drop S into the Great Basin and a deepening trough begins to form along the California/Arizona/Mexico border. As the week progresses, clouds and returning moisture from an onshore flow and pressures falls to our West suggest warm and windy conditions with streamer showers may well return in earnest by Thursday into Friday.

Next weekend may offer a stormy period as a potent Winter Storm develops to our W and very slowly meanders E. There are still strong indications that a very noisy sub tropical jet and cool Canadian air will become and issue in the medium range and beyond. The long range GFS/Euro and their ensembles are hinting that a series of upper air disturbance will become entrenched across the Great Basin/Central/Southern Rockies and the Southern Plains lending to a chilly stormy pattern that may linger for several days. The MJO has entered phase/octant 8 and the latest Global ensemble data suggest the MJO will enter phase/octant 1 near the mid February time frame. The fly in the ointment develops across the Northern Hemisphere as a +PNA Pacific Ridge develops as well as a tanking AO and indications of a blocking W based -NAO pattern develops lending to a general troughy pattern over much of North America and a reloading of very chilly air across E Alaska/W Canada. We'll need to watch the mid February time frame for a return to a Winter like pattern which would fit well climo wise for our Region. Stay Tuned!

Euro Ensembles:

The attachment 02022013 00Z Euro Ensembles 00zECMWFENS500mbHeightAnomalyNA240.gif is no longer available

The attachment 02022013 00Z Euro Ensembles 00zecmwfenshourly850mbTempAnomalyNA240.gif is no longer available

GEFS:

[Portastorm]

An excellent synopsis, srain! Looks like we enjoy another week of mild temperatures before Old Man Winter makes his (perhaps last) return. I will welcome that precipitation regardless of what form it comes in. The more, the merrier.

[srainhoutx]

HPC Medium Range Morning Update:

EXTENDED FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER COLLEGE PARK MD
1041 AM EST SAT FEB 02 2013

VALID 12Z TUE FEB 05 2013 - 12Z SAT FEB 09 2013

...GENERAL FLOW PATTERN...

THE UPPER VORTEX POSITIONED OVER HUDSON BAY WILL RETREAT NORTHWARD
OVER THE NEXT WEEK TO NEAR 70N OVER THE CANADIAN ARCHIPELAGO
/NUNAVUT/. THIS SHOULD ALLOW THE RETURN OF A SPLIT FLOW PATTERN
OVER THE CONUS WITH WEAK NORTHERN STREAM CLIPPER SYSTEMS IN THE
NORTHERN CENTRAL/EASTERN STATES AND A MORE SIGNIFICANT SYSTEM
MOVING THROUGH THE SOUTHWEST BY THE END OF THE WEEK NEXT WEEK.

...MODEL PREFERENCES...

THE DETERMINISTIC MODELS CONTINUE TO SHOW BETTER THAN AVERAGE
AGREEMENT ALL THE WAY THROUGH SAT/D7 WHILE THE ENSEMBLES SHOW LESS
THAN AVERAGE SPREAD... LEADING TO ABOVE AVERAGE CONFIDENCE IN THE
SYNOPTIC FORECAST. THE DIFFERENCES BETWEEN THE GEFS AND ECMWF
ENSEMBLE MEMBERS HAVE CHANGED LITTLE OVER THE PAST 2-3 DAYS... AS
THE ECMWF MEMBERS ARE GENERALLY JUST A BIT SLOWER AND MORE
AMPLIFIED WHILE THE GEFS MEMBERS ARE A BIT QUICKER AND FLATTER.
THE OVERLAP BETWEEN THE COMBINED 70-MEMBER ENSEMBLE ORCHESTRA HAS
PROVED TO BE A GOOD STARTING POINT FOR THE FORECAST... AND THIS IS
BEST REPRESENTED BY A BLEND OF THE 00Z ECMWF WITH VARYING WEIGHTS
OF THE 00Z-06Z GFS. THE 00Z CANADIAN AND UKMET FALL SLIGHTLY
OUTSIDE THE BETTER GFS-ECMWF AGREEMENT BUT ARE STILL OFFER
POSITIVE SUPPORT.

...SENSIBLE WEATHER IMPACTS...

IN THE EAST... THE GUIDANCE FAVOR A STORM TRACK THAT ARCS FROM THE
DAKOTAS AND UPPER MISSISSIPPI VALLEY THROUGH THE MIDWEST AND INTO
THE MID ATLANTIC STATES... BEFORE EXITING INTO THE WESTERN
ATLANTIC OCEAN. THESE CLIPPERS WILL BE GENERATING PERIODS OF LIGHT
SNOWFALL ACROSS THEIR NORTHERN FLANKS WHILE THE CANADIAN AIRMASS
IN PLACE MODERATES OVER TIME. BY THU/D5 INTO SAT/D7... HEIGHTS ARE
FORECAST TO RISE GIVING A BOOST TO TEMPERATURES OVER THE
MID-ATLANTIC/NORTHEAST OF ABOUT 10-15 DEGREES. NORTHERN STREAM
DOMINANCE WILL LIMIT PRECIPITATION TO ABOUT A QUARTER INCH
/MELTED/ IN FAVORED AREAS WITH LESSER AMOUNTS ELSEWHERE.

IN THE WEST... ONE SYSTEM WILL PUSH INTO THE PAC NW TUE/D3 AND
CONTINUE EASTWARD THROUGH THE HIGH PLAINS WED-THU/D4-5 WITH LIGHT
TO PERHAPS MODERATE QPF. THE MORE ROBUST TROUGHING IS FORECAST TO
MOVE INTO WA THU/D5 AND DIG THROUGH CA/NV AS RIDGING IN ITS WAKE
PUSHES INTO BRITISH COLUMBIA. FORECAST STANDARD DEVIATIONS OF
500MB HEIGHT BY THE ENSEMBLES ARE IN THE -2 RANGE AND THIS
BROAD-SCALE LIFT WILL USHER IN A MUCH COLDER AND UNSTABLE AIRMASS
INTO THE GREAT BASIN AND FOUR CORNERS REGION.

ANTICIPATE A GRADUAL SLOWDOWN OF THE UPPER TROUGH... WITH A
DEEPENING LEE SIDE TROUGH AND BROAD-SCALE UPSLOPE FLOW COMPONENT
TO TAKE SHAPE OVER WYOMING AND COLORADO IN ADVANCE OF THE UPPER
TROUGH. MODERATE TO HEAVY PRECIPITATION IS POSSIBLE NORTH OF THE
SFC LOW EJECTING OUT OF THE FOUR CORNERS REGION AS WELL AS
DOWNSTREAM AHEAD OF THE COLD FRONT THROUGH TEXAS INTO MS AND AL BY
THE WEEKEND. THIS IS DEPENDENT ON HOW MUCH ENERGY CLOSES OFF OVER
THE SOUTHERN ROCKIES... WHICH ADDS SOME UNCERTAINTY TO THE DETAILS.


FRACASSO/VOJTESAK

[srainhoutx]

The 12Z Operational long range GFS certainly agrees with the idea of a fairly stormy chilly pattern developing during the mid February time frame. We will see.

The attachment 02022013 12Z GFS 12zgfs500mbHeightAnomalyNA360.gif is no longer available

[Texas Pirate]

Yeah, the groundhog saw his shadow - we're moving on to WARM & SPRING.
I can see my flip flops from my backyard.

[srainhoutx]

Our string of Chamber of Commerce weather will transition to a unsettled pattern this week with a chance of rain every few days as short wave energy traverses the Region throughout the upcoming work week. Temps will remain mild with lows in the 50's and highs in the low to mid 70's.

A pattern change lurks later in the week as a potent N Pacific storm system arrives onshore next Thursday and drops into the Great Basin and a trough becomes established to our W. There remains some uncertainty in the forecast late next week as the Euro is a bit more progressive ejecting a cold core upper low into the Plains while the GFS is a full 12-18 hours slower and leaves energy behind buried along the US/MX border in Arizona. The end result will have some rather important impacts on the sensible weather expected Friday into next weekend. A slower more cut off solution tends to favor a potential severe weather event and a strong cold front as cyclogenesis occurs over the Panhandle while a progressive or faster moving storm system would favor a drier solution and less of an intrusion of 'colder' air. There are strong indications that the 500mb upper low will be very chilly with temps near the-32F range aloft. The HPC favors a slower/stormy pattern to our W with a return to a Winter like pattern with bouts of heavy snow across the Great Basin, Southern/Central Rockies into the Plains and lower elevation rains across the Pacific NW and California as well as a 7 Day QPF potential of near 1 inch for the Rio Grande Valley into Central Texas increasing to 2 to 3 inches along Coastal SE Texas into Louisiana and the Northern Gulf Region. We will need to monitor the trends this week as there remains a lot of uncertainty in the medium forecast and any potential severe episode for next weekend.

The attachment 02032013 HPC 10Z Day QPF p168i.gif is no longer available

00Z Euro Ensemble:

06Z GEFS:

GEFS MJO:

Euro Ensemble MJO:

[SaskatchewanScreamer]

The conditions, as of yesterday, here.....please, oh please, take it!

[SusieinLP]

SS, that looks miserable. Currently 57 where I am and I like it

[srainhoutx]

HPC Morning Updated Medium Range Discussion:

EXTENDED FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER COLLEGE PARK MD
1047 AM EST SUN FEB 03 2013

VALID 12Z WED FEB 06 2013 - 12Z SUN FEB 10 2013


...WINTER RETURNING TO THE INTERMOUNTAIN WEST AND CENTRAL PLAINS
FRIDAY TO SUNDAY...

...SYNOPSIS...

WE CONTINUE IN AN OSCILLATING PATTERN OF DRY AND SEASONABLY COLD
WEATHER ANCHORED BY LOW HEIGHTS IN THE EAST...FOLLOWED BY PERIODS
OF PROGRESSIVE FLOW AND A NORTHWARD SURGE OF WET AND VERY WARM
WEATHER THAT BETTER RESEMBLES EARLY SPRING. THE CURRENT DAY 3-7
FORECAST FEATURES THE LATTER...WITH THE DOMINANT FEATURE BEING A
PROGRESSIVE DEEP TROUGH THAT REACHES THE INTERMOUNTAIN WEST AND
CENTRAL U.S. BY NEXT WEEKEND. A NOTEWORTHY SYSTEM MAY ALSO OCCUR
ALONG THE EAST COAST DURING THE TRANSITION PERIOD LATE IN THE WORK
WEEK. THE 00Z ECMWF INDICATES THE POSSIBILITY OF A SIGNIFICANT
STORM...BUT CURRENT THINKING IS THAT A LESSER STORM MOVING QUICKLY
OUT TO SEA IS THE MORE LIKELY SCENARIO.

...MODEL CHOICE...

THE MODELS ARE SIMILAR IN WAVE SPACING AND TIMING DURING THE
DEVELOPING PROGRESSIVE FLOW WHICH RUNS FROM THE CENTRAL PACIFIC
ACROSS NORTH AMERICA. THIS MAKES IT RELATIVELY EASY TO IDENTIFY
THE STRONG OR WEAK OUTLIERS...AND MAKE A FORECAST NEAR THE MIDDLE
OF THE SPREAD. IN DOING THIS...THE SURFACE FORECASTS WERE
PARTICULARLY USEFUL...AND WE CHOSE MODELS THAT MET OUR
EXPECTATIONS FOR THE RESPECTIVE INTENSITIES OF A LOW OVER NEW
ENGLAND ON FRIDAY AND ANOTHER OVER THE CENTRAL PLAINS ON
SATURDAY/SUNDAY. THE MOST NOTABLE OUTLIER WAS THE 00Z
ECMWF...WHICH FORMS MORE OF A CLASSIC NOR'EASTER ON FRIDAY. THIS
RESULTS FROM A LOW THAT ORIGINATES OVER THE NORTHERN GULF OF
MEXICO AND TAKES A CLASSIC TRACK AROUND THE SOUTHERN END OF THE
APPALACHIANS AND UP THE EAST COAST. THE LOW MAY FORM IN THE
NORTHERN GULF AS A RESULT OF ENERGY CURRENTLY DIGGING TOWARD
MEXICO. THE ECMWF...HOWEVER...WAS SUBSTANTIALLY DEEPER THAN ALL
OTHER MODELS WITH AN UPSTREAM TROUGH THAT PICKS UP THIS FEATURE
AND ALLOWS THE EAST COAST CYCLOGENESIS TO OCCUR. ALTHOUGH A
HANDFUL OF ECMWF ENSEMBLE MEMBERS DO THE SAME THING...THE ECMWF
ENSEMBLE MEAN IS LESSER AMPLIFIED. THE PATTERN THIS WINTER HAS
TENDED TO PROMOTE PROGRESSIVE SYSTEMS THAT ARE FARTHER OUT TO SEA
BEFORE THEY INTENSIFY. THE GFS RUNS...ALONG WITH THE
UKMET...CONTINUE TO SUPPORT THIS NOTION...WITH EMPHASIS ON A
NORTHERN STREAM SHORWAVE AND ASSOCIATED SURFACE LOW WHICH GAINS
STRENGTH AS IT EXITS NEW ENGLAND FROM WEST TO EAST. WHILE THE
ECMWF SOLUTION IS NOT IMPOSSIBLE...THERE IS NOT ENOUGH OF AN
ESTABLISHED TREND TO GIVE IT MUCH WEIGHT IN THE FORECAST.

BACK TO THE WEST...WE DID GIVE THE ECMWF AND EC ENSEMBLE MEAN MORE
WEIGHT AS THE GFS RUNS AT 00Z AND 06Z WERE SLOWER AND SOMEWHAT
DEEPER THAN CONSENSUS.

...IMPACTS...

LOCALLY HEAVY RAIN IS POSSIBLE ALONG THE IMMEDIATE GULF COAST DAYS
3/4. HEAVY RAIN WILL BECOME MORE LIKELY ON DAY 7 WITH CYCLOGENESIS
AND A PACIFIC FRONT TAPPING INTO GULF MOISTURE OVER THE
CENTRAL/SOUTHERN PLAINS AND ADJACENT MISSOURI/MISSISSIPPI VALLEYS.
ON THE BACK SIDE OF THE SYSTEM...WINTER WEATHER INCLUDING HEAVY
SNOW IS POSSIBLE FROM THE INTERMOUNTAIN WEST INTO THE CENTRAL
PLAINS. AS WE TRANSITION TO ANOTHER BRIEF PERIOD OF SOUTHWEST
UPPER FLOW AND SOUTHERLY LOW LEVEL FLOW ACROSS THE SOUTHEASTERN
HALF OF THE COUNTRY...TEMPERATURES AGAIN WARM TO WELL ABOVE
AVERAGE FOR BOTH MAX AND MIN TEMPERATURES.

BURKE

[ticka1]

bring back winter!

[kennethb]

Vegetation and wildlife are usually indicators of temperature zones and impacts and effects of winter temperatures.

Here in Baton Rouge to indicate how we have not had too much in the way of freezes, usually by the middle of December we have had temps in the mid 20's that I put out bags of leaves on top of my various tender plants. Once the cold has passed I will take the bags of leaves off and put next to the plants so I can replace for the next freeze. I will also stack some bags of leaves around my water intake into the house to keep it protected. This is the first year since I moved in in 1998 that I have not even had to put the bags of leaves out. In fact the tropical perennials are still growing. I have roses blooming. After winter is over I will break the bags of leaves open and use in my garden and flower beds.

Usually by the middle to end of December I hear and see the first schools of cedar waxwings as they shrill and flock together in the winter sky. You usually hear them first and then see them as they fly together to the various berries in the trees and shrubs.

Yet though I am outside quite a bit, I have yet to hear/see any cedarwaxwings.

I am tempted to put out my tomato plants, but I know better.

[srainhoutx]

The 12Z operational Euro trended to what the GFS and its ensembles have been suggesting with a less progressive pattern and a potent Winter Storm developing next Friday into the weekend. In the cold sector, heavy snow and lower elevation rain break out across the Great Basin/Southern/Central Rockies into the Central Plains. Lee side cyclogenesis with increasing Gulf moisture returns suggest a severe potential may well be increasing across Texas on E into Arkansas and Louisiana and points E.

[Ptarmigan]

The 12Z operational Euro trended to what the GFS and its ensembles have been suggesting with a less progressive pattern and a potent Winter Storm developing next Friday into the weekend. In the cold sector, heavy snow and lower elevation rain break out across the Great Basin/Southern/Central Rockies into the Central Plains. Lee side cyclogenesis with increasing Gulf moisture returns suggest a severe potential may well be increasing across Texas on E into Arkansas and Louisiana and points E.

Looks to be an interesting week ahead. We could use more rain for sure.

[srainhoutx]

The trends via the Global Operational and Ensemble guidance as well as the short term meso models are suggesting an active zonal pattern with showers and isolated storm chances throughout the coming week.

As we head toward the late week time frame, the ensembles are coming into better agreement a significant pattern change will begin and a potent Winter Storm develops across the Great Basin and Intermountain West. What raises an eyebrow comparing this potential event is much better dynamics and abundant Pacific moisture as well as a stout return flow off the Gulf becoming well established ahead of the next weekend storm. Another point that is worth mentioning are that better dynamics may well be a bit further W into New Mexico which would tend to lend credence to a stronger severe potential for Texas/Oklahoma and possibly into Kansas and points E.

The longer range guidance continues to advertise a return of 'chilly' weather and a continuation of a unsettled pattern into the mid February time frame as the southern stream becomes very noisy and even a potential of a NW Gulf Coastal low developing early next week. My hunch is we are entering a very interesting and active pattern ahead. We will see...

Edit to add: It appears we may get some help from WSR (Winter Storm Recon) for the Pacific this week...

Code: Select all

000
NOUS42 KNHC 031616
REPRPD
WEATHER RECONNAISSANCE FLIGHTS
CARCAH, NATIONAL HURRICANE CENTER, MIAMI, FL.
1115 AM EST SUN 03 FEBRUARY 2013
SUBJECT: WINTER STORM PLAN OF THE DAY (WSPOD)
         VALID 04/1100Z TO 05/1100Z FEBRUARY 2013
         WSPOD NUMBER.....10-065

I.  ATLANTIC REQUIREMENTS
    1. NEGATIVE RECONNAISSANCE REQUIREMENTS.
    2. OUTLOOK FOR SUCCEEDING DAY.....NEGATIVE.

II. PACIFIC REQUIREMENTS
    1. NEGATIVE RECONNAISSANCE REQUIREMENTS.
    2. SUCCEEDING DAY OUTLOOK.....POSSIBLE 
       P56/ DROP 9 (44.2N 151.0W)/ 06/0000Z.

[Portastorm]

Using the AccuWx PPV Euro graphics, the main action w/ the storm next weekend basically misses HOU to the North, but the front stalls just offshore, with fairly decent rains on the cold side over my back yard Monday and Tuesday.

The Sunday fun-derstorm potential would be in Northeast Texas per Euro.

But a week out, and even if verifies verbatim, and its all post frontal rain, looking like a couple of inches, and we need the rain.

And, sort of OT, the big I-95 cities are hating Winter even more than we are. Warm side of both Friday and Monday storm, and the next storm after looks to warm sector them as well...

We'd certainly welcome several inches of rain here in south central Texas. We may be too far north from the stalled front offshore but we're still a ways away from the details.

[JackCruz]

My hunch is we are entering a very interesting and active pattern ahead. We will see...

I've heard this so many times Srain, and still no snow or really cold temps for Houston....what's gonna be so interesting? Sleet?

[C2G]

Interesting doesn't necessarily mean extreme cold accompanied with snow, sleet, and freezing rain. Could just mean inclement weather, which usually equates to liquid form in southeast Texas.
We need all the rain we can get in these weeks ahead.
You will learn srains style soon enough, which usually equates to instigating conversation out of thin air.

[srainhoutx]

As Cloud2ground so eloquently stated Jack Cruz, and Ed eluded to, my role is to keep the conversation flowing and to offer input to a wide audience concerning weather potentials, be it cold, wintry, severe, tropical or drought...from fire to ice for a very large Region. We have to remember the weather effects us all in some form or fashion and that is the draw of our Weather Community and those that follow our musings. Weather is an interest to many from planning purposes such as will it rain or storm for Mardi Gras events in Galveston to New Orleans next weekend to the construction worker with out door projects on schedule to the teacher that utilizes our Weather Board as a teaching tool to help make 'science interesting'. You see, our online Weather Community stretches well beyond our own back yard and what makes our forum a 'go to' place for our Region is we tend to be ahead of the Weather headlines, whatever those weather events may be.

An active week appears ahead with a couple of short wave disturbance traversing across Texas, one being tonight into early tomorrow and a second upper air disturbance moving from W to E on Wednesday into Thursday. Showers and isolated storms are possible with both features.

There continues to be a lot of uncertainty regarding the upcoming weekend and early next week. What we do know is a deep trough with a Potent Winter Storm will develop to our W. In fact NOAA has so little confidence in the computer model guidance, they have tasked a G-IV high altitude jet to fly over the Pacific and sample the environment for ingest into those computer models for more accurate data output and to assist the forecasters with how this strong storm system will affect the Country. To our W, wintry conditions appear likely. Because lack of guidance continuity, the implications of how that storm ejects from the Great Basin is the main concern for the forecaster. The HPC is mentioning this morning the similarity to a Spring like storm we tend to see in late March/early April meaning a wide spread severe weather event in the warm sector with wintry mischief in the cold sector or behind the storm. The fly in the ointment is will there be phasing, or a joining of the northern jet stream with the active southern jet stream storm which would tend to pull down cold air from the N and collide with warm moist Gulf air to the S. We are in a somewhat zonal split flow pattern where cold air has retreated N with an active northern stream and a secondary active southern stream where this storm system will organize later this week. All in all a very active pattern is ahead and for our Region, rain chances are returning this week. The finer details should become bit clearer later in the week regarding next weekend and the sensible weather we can expect.



EXTENDED FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER COLLEGE PARK MD
142 AM EST MON FEB 04 2013

VALID 12Z THU FEB 07 2013 - 12Z MON FEB 11 2013


DAYS 3-5...
OVERNIGHT SURFACE GRAPHICS WERE ABLE TO MAINTAIN VERY GOOD
CONTINUITY WITH A BLEND OF THE 3/12Z ECMWF AND ITS ENSEMBLE
MEANS...ALONG WITH SOME OF THE 3/12Z UKMET. THE 4/00Z GFS GETS TO
BE A FAST OUTLIER BY FRIDAY (DAY 4) WITH THE 'CLIPPER' RACING
THROUGH THE OHIO VALLEY AND OFFSHORE INTO THE WESTERN ATLANTIC.
THE 4/00Z UKMET-ECMWF WERE BETTER FITS TO THE MANUAL GRAPHICS AND
THE PATTERN EVOLVING VS THE 4/00Z GFS-CANADIAN.

WITH MUCH OF THE 4/00Z GUIDANCE IN...THERE IS PLENTY OF SUPPORT
FOR COMPLEX COASTAL WAVE DEVELOPMENT AND SECONDARY INTENSIFICATION
OF A SURFACE WAVE OFF THE IMMEDIATE COASTLINE (IN THE OUTER BANKS
AND BLOCK ISLAND CORRIDOR) ON FRIDAY AFTERNOON/EVENING. THE MANUAL
GRAPHICS CERTAINLY ARE NOT PERFECT PROGS...BUT I DID DRAW A SFC
LOW TRACK (AND INTERMEDIATE POSITION)...PASSING OVER THE BENCHMARK
BEFORE 9/00Z IN THE NEIGHBORHOOD OF 1004 MB AND DEEPENING TO 996MB
EAST OF HALIFAX NS AROUND 9/12Z. THIS INTERMEDIATE PROG (VALID
9/00Z) IS CLOSER TO THE 4/00Z UKMET FOR DEPTH BUT HONORS THE TRACK
OF THE 3/12Z ECMWF PACKAGE AND THE 4/00Z OPERATIONAL ECMWF. THE
DEEPEST SFC PRESSURE AT 983 MB AS IT ENTERS THE SW GULF OF MAINE
AFTER 9/00Z MIGHT BE OVERDONE...BUT THE TRENDS FROM YESTERDAY
SUPPORT ONE LAST CYCLONE (CLIPPER) BEFORE THE ARCTIC AIRMASS
RETREATS AWAY FROM THE EASTERN SEABOARD.

DAYS 6-7...
THE MEDIUM RANGE GUIDANCE HAD A GOOD HANDLE ON THE WEST COAST
TROUGH AND MODERATELY-INTENSE CYCLONE EXITING THE SOUTH CENTRAL
ROCKIES NEXT WEEKEND. AS ENVISIONED A COUPLE OF DAYS AGO...THE
SYSTEM HAS SLOWED A TAD...BUT WILL SWEEP SOME PACIFIC ENERGY AND A
WEAK SURFACE REFLECTION ACROSS THE NORTHERN ROCKIES AND THROUGH
THE NORTH DAKOTA PLAINS BEFORE THIS NORTHERN END OF THE FRONT
WEAKENS IN NORTHERN MINNESOTA AND WESTERN ONTARIO.

THE MANUAL H5 TRACK FOR THIS SYSTEM DOWNSTREAM OF THE FRONT RANGE
WAS DRAWN WITH A 'BEST FIT' LINE FROM PUEBLO CO TO MINNEAPOLIS MN
GIVEN THE VARIABILITY IN TRACK AND SPEED. THE GFS IS THE MAIN
REASON THERE IS 'INTRODUCED UNCERTAINTY'. I CAN NOT REALLY FOLLOW
ITS RUN TO RUN ADJUSTMENTS...BUT THE H5 TRACK IS NOT FAR FROM THE
TRACK ENVISIONED FOR NEXT WEEKEND. THE WESTERN GOMEX SHOULD BE
WIDE OPEN AHEAD OF THIS CYCLONE.

THE ONE TREND THAT WILL NEED TO BEAR WATCHING...IS...HOW THE
INTENSE WEST-NORTHWESTERLY FLOW SURGING THROUGH THE 4 CORNERS AND
SOUTHERN DIVIDE REGION ON SATURDAY TRANSLATES DOWNSTREAM OVER THE
SOUTHERN HIGH PLAINS OF ERN NM/WRN TX LATER ON SATURDAY AFTERNOON
AND EVENING. IN SOME RESPECTS...THIS PACIFIC SYSTEM LOOKS MORE
LIKE A LATE MARCH/EARLY APRIL SYSTEM... WITH A WELL-DEFINED DRY
SLOT AND WARM ADVECTION WORKING NNEWD ACROSS THE TX PANHANDLE AND
SOUTH CENTRAL KANSAS...AND INTO THE H5 CYCLONE'S CIRCULATION. THIS
MAY END UP SHIFTING THE GULF MOISTURE EAST AND SOUTH OF THE COLD
FRONT INITIALLY...AND BRIEFLY LIMIT THE PHASING OF THE LOW-LEVEL
MOISTURE LIFTING ATOP THE COLD SECTOR OF THIS SYSTEM INVOF 40N
LATITUDE AND BETWEEN 94W-99W LONGITUDE. LIKEWISE..A DRIER EASTERLY
LOW-LEVEL FLOW IS ANTICIPATED TO BE WORKING INTO THIS SYSTEM ALONG
ITS NORTHERN PERIPHERY THROUGH EARLY SUNDAY.

VOJTESAK