November 2015: Ending Cold & Rainy

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srainhoutx
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The afternoon Updated QPF is 'sniffing' out another potential heavy rainfall and severe episode later this weekend into early next week. Notice the Pacific NW QPF is showing some 16+ inches which as these powerful bowling ball upper lows persistently dropping South into an ever deepening Western Trough, look for powerful storm systems to organize over New Mexico and NW Texas possibly extending throughout the remainder of November into early December...at least.
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T'is the season...
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srainhoutx wrote:The afternoon Updated QPF is 'sniffing' out another potential heavy rainfall and severe episode later this weekend into early next week. Notice the Pacific NW QPF is showing some 16+ inches which as these powerful bowling ball upper lows persistently dropping South into an ever deepening Western Trough, look for powerful storm systems to organize over New Mexico and NW Texas possibly extending throughout the remainder of November into early December...at least.
The heavy rain over Pacific Northwest is Mt. Olympus. It is the wettest area in the Lower 48.

Olympic Mountains
https://en.wikipedia.org/wiki/Olympic_Mountains

They see 240 inches of rain a year on average!
Last edited by Ptarmigan on Tue Nov 10, 2015 10:26 pm, edited 2 times in total.
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Eurasian Snow Cover Variability and Links with Stratosphere-Troposphere Coupling and Their Potential Use in Seasonal to Decadal Climate Predictions
http://www.nws.noaa.gov/ost/climate/STI ... 062211.pdf

What role Siberian snow cover has on cold winter in America.
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Much respect on this Veterans Day to everyone who has served the USA for protection and freedom. Many thanks for your sacrifice.

Fast moving cold front to move across SE TX and offshore this afternoon and evening. Showers and thunderstorms will occur along and ahead of front and might be more likely along the coastal areas. The SPC has a marginal risk area across NE, E, SE, and portions of S Central TX so a few isolated strong thunderstorms may be possible depending on the strength of the CAP. After the frontal passage SE TX looks to have some cool days and nights with partly cloudy skies through Saturday evening. Slight rain chances look to enter the picture Saturday night ahead of the next storm system and front. Much colder weather may arrive next week.
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srainhoutx
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Morning briefing from Jeff:

Several storm systems to affect the region over the next week.

Strong moisture advection overnight has raised dewpoints by a solid 10-15 degrees across the region as the next storm system rapidly approaches TX this morning. Impressive mid November storm system will intensify over the Midwest today pushing cold front into this increasing moist and unstable air mass over SE TX. Strong jet stream dynamics will come into play mainly north of SE TX this afternoon and early evening allowing the capping inversion (mid level warm temperatures) to erode. Lift from the front will likely help to force surface parcels through the weakening cap by late afternoon allowing the rapid development of showers and thunderstorms along the boundary. Shear profiles will be favorable for damaging winds and even a few isolated tornadoes especially north of I-10. Expect a line of thunderstorms (possibly broken) to cross the area between 600pm and midnight.

Front will clear the coast before sunrise on Thursday with northerly flow in place and a much drier and cooler air mass. Active sub-tropical jet overhead may maintain a scattered high level deck with filtered sun both Thursday and Friday. Clouds return late Friday and…getting ready…clouds will likely remain in place for much of the next week.

Prolonged active weather event starting to shape up for next week with significantly colder temperatures and extended wet weather. Sub-tropical jet stream becomes increasingly active over the weekend. Models are pushing back the onset of rainfall more into later on Sunday now versus Saturday and this seems reasonable given the pattern setup with a slow moving upper level storm system well to our west. Will bring back rain chances and humid conditions on Sunday and increase rain chances more Monday-Tuesday. A powerful cold front looks to cross the region late Tuesday with temperatures tumbling behind the boundary as cold air builds over the northern Rockies. Upper flow looks to remain out of the SW with yet another storm system dropping into the SW US by the end of next week keeping a wet and cold pattern in place. Latest GFS guidance has a high of 58 in Houston next Wednesday.


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NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
1110 AM CST WED NOV 11 2015

.UPDATE...
SEE MORNING UPDATE.

&&

.DISCUSSION...
VIS SATELLITE SHOWING A FEW BREAKS IN THE CLOUD COVER. ANY
SUNSHINE WILL AID IN HEATING SO WILL BUMP TEMPS UP A BIT OVER THE
SOUTHERN HALF OF THE CWA. RECORD HIGH AT GLS TODAY IS ONLY 81
DEGREES SO THAT RECORD IS IN JEOPARDY. SOME STREAMER SHOWERS
DEVELOPING OVER THE WESTERN ZONES AND THESE LIGHT SHOWERS WILL
PERSIST THROUGH THE AFTERNOON. STILL A MARGINAL TO SLIGHT RISK OF
SEVERE STORMS THIS EVENING AS A COLD FRONT CROSSES SE TX. 12Z
SOUNDINGS STILL SHOW A SIGNIFICANT CAP ACROSS SE TX AND MOST OF
THE MODELS CONTINUE TO SHOW THE CAP ERODING BETWEEN 21-00Z. 43

&&

.PREV DISCUSSION... /ISSUED 518 AM CST WED NOV 11 2015/

DISCUSSION...
QUITE A DIFFERENCE IN THE LAST 24 HRS FOR SE TX. SEEING GENERALLY
+10F TEMP/DEWPT CHANGES (WITH A FEW SITES TO ALMOST +20F). ALL OF
THIS IS IN ADVANCE OF A COLD FRONT THAT IS STILL EXPECTED TO MOVE
ACROSS THE AREA LATER TODAY. THE STRONG CAP OVER THE AREA WILL BE
ERODING THROUGHOUT THE DAY...HELPED ALONG BY THE PASSAGE OF UPPER
LEVEL DISTURBANCES EMBEDDED WITHIN THE SW FLOW ALOFT. THESE S/WVS
COMBINED WITH FAVORABLE JET DYNAMICS SHOULD HELP TO PRODUCE SHRA/
TSRAS ALONG AND AHEAD OF THE FRONT. THE RAPID MOVEMENT OF THE SFC
LOW TO THE NE WILL ALLOW FOR RAPID CLEARING WITH FROPA. WEAK/FLAT
UPPER RIDGING TO KEEP THINGS QUIET THROUGH THE END OF THE WEEK AS
TEMPS REMAIN AT OR JUST BELOW SEASONAL NORMS.

LONG RANGE PROGS REMAIN SOMEWHAT DIVERGENT WITH THE UPCOMING PAT-
TERN. WHILE WE ARE STILL SEEING A WEAK UPPER TROF MOVE ACROSS THE
CENTRAL PLAINS OVER THE WEEKEND WITH POPS (RETURNING STARTING SAT
NIGHT ON INTO SUN)... MODELS ALSO REMAINING FOCUSED ON THE DEVEL-
OPMENT OF THE NEXT STRONGER SYSTEM. GFS KEEPING WITH A SLOWER AND
DEEPER TROF THAN THE ECMWF WITH THESE RUNS. LEANING MORE WITH THE
GFS ATTM (GIVEN ITS CONSISTENCY/SLOWER TIMING) IN THE EXTENDED...
BUT SHOULD IT VERIFY WE COULD BE IN SOME CHILLY TEMPS NEXT WEEK.
41

MARINE...
WINDS PICKING UP AS EXPECTED THIS MORNING AND HAVE SCECS FOR ALL
WATERS...MAY NEED AN SCA FOR THE GULF WATERS AS WINDS COULD
INCREASE THIS MORNING TO AROUND 20 KNOTS AND BE GUSTY. WINDS THEN
DECREASE LATE THIS AFTERNOON/EVENING AS COLD FRONT MOVES INTO SETX
LIKELY REACHING THE COAST AROUND 1-3 AM THURSDAY. MODERATE TO
STRONG NW-N WINDS DEVELOP IN THE WAKE OF THE FRONT AND HAVE
HOISTED SCA FLAGS FOR THE GULF WATERS AND SCEC FOR BAYS. SHOWERS
SHOULD BE THE PRIMARY PRECIPITATION ALONG AND AHEAD OF THE FRONT
BUT ISOLATED THUNDERSTORMS STILL SEEM POSSIBLE IF THEY CAN SURPASS
THE PROMINENT CAP AROUND 825MB. BY 3-6 AM THURSDAY MAY EVEN SEE A
FEW STRONG THUNDERSTORMS IN THE FAR COASTAL WATERS WHERE GREATER
INSTABILITY AND LESSER CAP SHOULD EXIST.

HIGH PRESSURE DOMINATES SETX THU-SAT MAINTAINING A PERSISTENT NE
FLOW OVER THE WATERS FLUCTUATING BETWEEN 15-22 KNOTS. WINDS THEN
START TO VEER AS NEXT SYSTEM APPROACHES. CONCERN FOR A STRONGER AND
MUCH MORE POTENT COLD FRONT ARRIVES AROUND TUESDAY-WEDNESDAY.
EXTENDED GUIDANCE HAS BEEN BOUNCING AROUND THIS EVENT AND APPEARS TO
BE NARROWING IT DOWN. COULD BE SOME VERY COLD AIR FOR THIS TIME OF
YEAR AND MAY BE GETTING CLOSE TO GALES WITH ITS PASSAGE.
45

AVIATION...
OVC 4000-5000FT DECK WITH AN MVFR DECK FORMING...DWH-6R3
NORTHWARD SO FAR BUT IT WILL LIKELY EXPAND SOUTHWARD TOWARD
MORNING. THIS MVFR DECK SHOULD PREVAIL THROUGH AT LEAST 18Z AND
MAY GO WELL INTO THE AFTERNOON HOURS. OTHER ISSUE IS WINDS...TDWR
/WSR-88D SHOWING LLWS PATTERN AT 1000-1800FT 30-42 KNOTS OUT OF
THE SSW. MODELS INDICATING THAT THIS SHOULD SLOWLY RISE AND VEER
FURTHER BY MID MORNING WHILE INCREASING IN STRENGTH THEN DIMINISH
THIS AFTERNOON WITH 15-21Z SW GUSTY WINDS PREVAILING. FOR NOW WILL
CARRY VCSH AND HOLD OFF ON VCTS UNTIL 00-06Z...WITH A PROB30 OR
TEMPO FOR PRECIP ALONG FROPA. NORTH WINDS IN THE WAKE OF THE FRONT
AND VFR CIGS...PERHAPS BKN060- 080 POST FRONTAL.
45

&&

.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 80 53 71 51 64 / 50 20 0 0 10
HOUSTON (IAH) 82 59 72 52 67 / 30 60 0 0 10
GALVESTON (GLS) 81 65 70 60 68 / 20 60 0 0 10

&&
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Being I work downtown - went and watch some of the parade - boy is it windy out there. With that note I would like to thank all the veterans who are members of this page - Happy Veterans Days and THANK YOU for your service. All and one.
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The latest 12Z guidance continues to advertise a very intense cold core upper low and a strong surface low developing across New Mexico and N Central Texas early next week. Typically neutral to negative tilt troughs with its attending pesky very robust cold core low create a myriad of weather issues from wrap around wintry mischief this time of year to severe weather in the warm sector. We are going to need to monitor develops the next several days as there could be heavy rainfall, all modes of severe weather and possibly some sleet/snow across New Mexico, West, NW and potentially N Central Texas into Oklahoma beginning Sunday and continuing into mid next week.
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DARK BLUE = I like! :D :D
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GFS is suggesting one hell of a system coming through the southern plains. A strong trough with multiple shortwaves rotating through looks to present a very wet beginning to next week. The GFS is even showing a possible severe event with EHI's in the 4-5 range. Of course this is all 5-6 days away, but we could see our first cold event of the year.
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Very thin but organized squall line headed towards metro in the next hour or two.
Surprising how well its held together for it being so thin. 10 degree drop with fropa.
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Andrew wrote:GFS is suggesting one hell of a system coming through the southern plains. A strong trough with multiple shortwaves rotating through looks to present a very wet beginning to next week. The GFS is even showing a possible severe event with EHI's in the 4-5 range. Of course this is all 5-6 days away, but we could see our first cold event of the year.
Another flood event possible? November has had nasty weather, especially with El Nino.
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snowman65 wrote:DARK BLUE = I like! :D :D
Lower pressure means stormy weather.
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Ptarmigan wrote:
Andrew wrote:GFS is suggesting one hell of a system coming through the southern plains. A strong trough with multiple shortwaves rotating through looks to present a very wet beginning to next week. The GFS is even showing a possible severe event with EHI's in the 4-5 range. Of course this is all 5-6 days away, but we could see our first cold event of the year.
Another flood event possible? November has had nasty weather, especially with El Nino.

The possibility exists but there still remains a lot of questions as to how progressive the system will be and where everything sets up.
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Temps are cooling and light rains moving offshore as the front moves across the Upper TX Coast. Partly cloudy skies through Saturday afternoon before rain chances begin to increase Saturday night. Models continue to show a powerful upper level low moving across TX Monday and Tuesday with the potential of a severe weather event as well as a heavy rain event. The SPC has SE TX in the 15% hatch area for severe weather Monday and Tuesday. A strong cold front will follow the storm system next week.
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The overnight guidance continues to advertise a powerful negative tilted trough moving out of the Southern Rockies Sunday into Monday and marching across Texas and Louisiana into Tuesday. If these trends continue, except to see all modes of severe weather possible including a threat for super cells and a possible tornado risk across portions of Central, East, SE Texas extending into Louisiana next Monday into Tuesday.

In the wake of this powerful late Fall/early Winter storm, expect the coldest air of the Season to spread South all the way to the Gulf Coast mid to late next week. Stay tuned folks. This storm system has the potential to be a Major Weather event across the Region.

00Z Euro:
The attachment 11122015 00Z Euro f120.gif is no longer available
11122015 00Z Euro f120.gif
00Z GFS
11122015 00Z Euro f144.gif
11122015 00Z GFS f120.gif
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srainhoutx wrote:The overnight guidance continues to advertise a powerful negative tilted trough moving out of the Southern Rockies Sunday into Monday and marching across Texas and Louisiana into Tuesday. If these trends continue, except to see all modes of severe weather possible including a threat for super cells and a possible tornado risk across portions of Central, East, SE Texas extending into Louisiana next Monday into Tuesday.

In the wake of this powerful late Fall/early Winter storm, expect the coldest air of the Season to spread South all the way to the Gulf Coast mid to late next week. Stay tuned folks. This storm system has the potential to be a Major Weather event across the Region.
Sounds like some exciting days ahead.This may be a precursor of what's ahead for our winter weather. :)
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EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
152 AM EST THU NOV 12 2015

VALID 12Z SUN NOV 15 2015 - 12Z THU NOV 19 2015

...HEAVY RAIN POSSIBLE IN THE MID AND LOWER MISSISSIPPI VALLEY
NEXT TUE-WED...

...OVERVIEW...
HIGH PRESSURE WILL ANCHOR OFF THE EAST COAST FOR THE BETTER PART
OF THIS MEDIUM RANGE PERIOD --- PRODUCING A WEAK ONSHORE FLOW THAT
WILL GENERATE LOCALLY CLOUDY CONDITIONS...BUT OVERALL A DRY AND
RATHER MILD PATTERN BY MID-NOVEMBER STANDARDS. THE WEATHER IN THE
WEST WILL HAVE AN UNUSUAL 'ALASKA' FEEL TO IT ... AND THE CENTRAL
PORTION OF THE CONTINENT ... MORE LIKE 'SPRING' WITH COOL
NIGHTS...MILD DAYS AND THREAT OF SHOWERS ALONG AND AHEAD OF THE
'PACIFIC' FRONTS MIGRATING DOWNWIND OF THE ROCKIES.

A DEEP CYCLONE MIGRATING ACROSS THE GULF OF ALASKA (IN THE SHORT
TERM) WILL BE A MAJOR SENSIBLE WEATHER FEATURE OF THE LOWER 48'S
WEATHER PATTERN DURING THE MEDIUM RANGE PERIOD. THE DEPTH OF THIS
SYSTEM AND ITS DEEP SURGE OF MODIFIED ARCTIC AIR --- WITH ORIGINS
IN NORTHEAST SIBERIA --- WILL BE TEMPORARILY LINKED WITH THE GULF
OF ALASKA AND NORTH AMERICA'S WEST CENTRAL COAST ---VIA A RATHER
PERSISTENT AND ACTIVE WEST-NORTHWESTERLY 250MB JET AXIS. THIS
POLAR JET BEGINS TO CARVE OUT A DEEP 250MB TROUGH ON DAY 3 ALONG
THE WEST COAST --- AND MIGRATES THIS SYNOPTIC-SCALE FEATURE
EASTWARD ACROSS THE CENTRAL PORTION OF THE CONTINENT THROUGH DAY 5
AND 6. IT'S EVENTUAL INTERACTION WITH A SOUTHERN JET AXIS WITH
ORIGINS NEAR HAWAI'I --- SHOULD SET THE STAGE FOR LARGE SENSIBLE
WEATHER CHANGES IN THE SOUTHERN ROCKIES AND PLAINS (DAYS 3-4) AND
MUCH OF THE MISSISSIPPI VALLEY (DAY 5).

...MODEL PREFERENCES...
HAVING THE LUXURY OF WATCHING THE EVOLUTION OF THIS PARTICULAR
SUB-968MB ALASKA CYCLONE LAST WEEK --- AND SEEING ITS RATHER DEEP
CENTER MIGRATING THIS MORNING --- TO A LOCATION VERY NEAR WHERE
THE ECMWF/GFS HAD IT 5-6 DAYS AGO... IT GIVES ME SOME CONFIDENCE
TO CONCLUDE WHERE IT WILL BE IN THE NEXT 4-5 DAYS. IN A WEAKENED
STATE --- OVER NORTH CENTRAL CANADA. BUT MORE IMPORTANTLY... IT'S
WHAT TRANSPIRES BEHIND IT AND WHERE THE TRAJECTORIES OF THE ARCTIC
AIR ASSOCIATED WITH THE MID-AUTUMN SYSTEM ARE HEADING ... THAT
POINTS TO USING A BLEND OF THE DETERMINISTIC 11/12Z-12/00Z
GFS/ECMWF THROUGH DAY 5. IN ADDITION... THESE PIECES OF GUIDANCE
CONTINUE TO PROVIDE GOOD BALANCE ---AND A SPLIT-FLOW OFF THE
CENTRAL CALIFORNIA COAST --- WITH A 100+ KT SUBTROPICAL SOUTHERN
JET AXIS EMERGING NORTH AND NORTHEAST OF HAWAI'I--- WITH AN ENTRY
POINT NEAR 30N 115W.

THIS 'SPLIT-FLOW' WILL NOT LAST LONG --- AND BY DAY 3 --- THE
NORTHERN STREAM BEGINS TO WORK ITS WAY SOUTH ALONG THE WASHINGTON
AND OREGON COAST... AND WILL BLEND BOTH THE 12/00Z DETERMINISTIC
ECMWF/GFS SOLUTIONS AND THEIR MEANS FOR THE DAY 4-5 QPFS. BEYOND
18/00Z ... THE DIFFERENCES BETWEEN THE GFS/ECMWF BECOME VERY
APPARENT --- AND VERY QUICKLY DO THE TWO JET STREAM DEVELOP A VERY
COMPLEX UPPER-LEVEL FLOW PATTERN NEAR THE OZARKS (AROUND 18/06Z).
AND THIS IS THE BEST DETAIL I CAN GIVE AT THIS POINT. USED A
11/12Z 70/30 ECENS/NAEFS BLEND FOR DAYS 6-7 TO ACCOUNT FOR THE
RATHER SHARP AMPLITUDE AND CHANGING CHARACTER OF THIS PARTICULAR
MIGRATORY 250MB PACIFIC TROUGH SEQUENCE.

...UNCERTAINTY ASSESSMENT...
BIGGEST UNCERTAINTY AT THIS POINT IN TIME IS --- HOW FAR SOUTH AND
FOR HOW LONG --- THE UNSTABLE PORTION OF THE NORTHERN STREAM
PACIFIC JET ("BACKSIDE") WILL DRIFT ONCE IT ENTERS THE WEST COAST
(ON/AROUND 16/12Z). THIS PORTION OF THE JET WILL CARRY A LARGE
PORTION OF THE ALEUTIAN/GULF OF ALASKA MARITIME POLAR AIRMASS WITH
IT SOUTHEASTWARD TOWARDS THE MAINLAND. THE JET-DRIVEN HEAVY
PRECIPITATION DIRECTED ACROSS THE COASTAL RANGES OF
WASHINGTON...THE WINDWARD OREGON CASCADES AND NORTHERN CALIFORNIA
IS A SCENARIO THAT HAS ABOUT A 48-HOUR LIFE CYCLE BETWEEN DAY 4
AND DAY 6 (PER THE 11/12Z-12/00Z DETERMINISTIC GFS/ECMWF). AND
BEHIND THE EXITING JET --- THE COLDEST AIRMASS OF THE YOUNG 'WET
SEASON' SPREADS INTO THE PACIFIC NORTHWEST.

HEADING INTO THE DAY 4-5 PERIOD...THE DETERMINISTIC GUIDANCE LIKES
THE IDEA OF THE SOUTHERN JET STREAM BEGINNING TO NOSE EASTWARD
INTO THE OZARKS AND LOWER MS VALLEY. BUT HOW MUCH OF THIS
JET-LEVEL ENERGY CAN PHASE WITH THE PREVAILING PACIFIC STREAM
PUNCHING ACROSS THE WEST COAST AND GREAT BASIN WILL BE THE
CHALLENGE.

MOVING FORWARD FROM 17/12Z (TUESDAY MORNING)... THERE ARE THREE
DIFFERENT SOLUTIONS WITH THE EASTWARD PROGRESSION OF THE 'PACIFIC'
FRONT---THE NORTHWARD SPREAD OF THE PRECIPITATION ALONG THIS
SOUTHERN JET AXIS AND HOW THE TWO 250MB JET AXES INTERACT AT/AND
BEYOND 18/06Z. FOR NOW --- THE 11/12Z GFS AND CANADIAN MAINTAIN A
HEAVY RAIN THREAT INTO WEDNESDAY --- THE 11/12Z ECMWF PUSHES THE
HEAVY RAINFALL DOWNWIND INTO THE APPALACHIANS. NO DOUBT --- THE
WESTERN GULF OF MEXICO WILL PARTIALLY-OPEN AND ALLOW A BROAD
LOW-LEVEL MOISTURE STREAM TO WORK NORTHWARD...BUT THE UNCERTAINTY
REMAINS IN THE ABILITY OF THE SOUTHERN JET TO GENERATE THE LIFT
AND PHASE WITH THE UPSTREAM SURFACE FRONT AND 250MB NORTHERN
STREAM JET MOVING THROUGH THE NORTHERN PLAINS. THIS IS THE PRIMARY
REASON BEHIND USING A 11/12Z ECENS/NAEFS BLEND WITH NO
DETERMINISTIC SUPPORT FOR DAY 6-7 SURFACE GRAPHICS AND QPFS.
SHOULD THESE TWO JET STREAMS PHASE --- THERE WILL BE POTENTIAL FOR
EVEN MORE HEAVY RAINFALL TO MIGRATE NORTHWARD INTO THE OHIO VALLEY
AND GREAT LAKES.

...SENSIBLE WEATHER HIGHLIGHTS...
MORE RAIN AND COLD-SECTOR SHOWERS FOR A LARGE PORTION OF THE WEST
AS THE LEADING EDGE OF THE DEEP TROUGH IN THE GULF OF ALASKA
MIGRATES EAST OF THE COASTAL RANGES AND BEGINS TO WORK ITS WAY TO
THE CONTINENTAL DIVIDE.

THE COMBINED EFFECTS OF TWO JET DISTINCTLY DIFFERENT 250MB JET
AXES --- A PACIFIC FRONT MOVING THROUGH THE CENTRAL PLAINS AND A
PARTIALLY-OPEN WESTERN GULF OF MEXICO ALL POINT TO THE POTENTIAL
FOR MORE HEAVY RAIN ACROSS PORTIONS OF TEXAS... OKLAHOMA... THE
OZARKS... AND MUCH OF THE SOUTHERN HALF OF THE MISSISSIPPI RIVER
VALLEY DURING THE EARLY PORTION OF THIS MEDIUM RANGE PERIOD.

VOJTESAK



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Worrisome to see very good agreement among the 12Z suite of operational guidance concerning the next in a series of powerful Southern Storms...
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