February: Calm Weather To End The Month

[Ptarmigan]

Code: Select all

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
531 AM CST SUN FEB 19 2012

A LOOK BACK AT THE RAIN SO FAR THIS YEAR.

THIS YEAR HAS STARTED OFF ON A WET NOTE WITH PERIODS OF HEAVY
RAIN AND HAS HELPED TO ALLEVIATE THE CRUSHING DROUGHT OF 2011.
LAST YEAR AT THIS TIME THE RAINS HAD TAPERED OFF AND THE DROUGHT
WAS GETTING UNDERWAY WHICH HAS MADE THIS QUITE A NOTICEABLE
CHANGE.

YESTERDAYS RAIN EVENT SET SOME RECORDS FOR GREATEST ONE DAY TOTALS.

RAINFALL DATA IN INCHES FOR FEB 18TH
CLL 1.16 PREVIOUS 2.64 IN 1963
IAH 1.89 PREVIOUS 2.09 IN 1938
HOU 2.57 PREVIOUS 1.62 IN 1963 (NEW RECORD)
GLS 2.85 PREVIOUS 2.10 IN 1924 (NEW RECORD)

CLL - HIGHEST DAILY PRECIPITATION FOR FEB 18TH
RANK  VALUE  ENDING DATE
  1    2.64    2/18/1963
**2    1.16    2/18/2012
  3    0.85    2/18/1990,  2/18/1988
  5    0.65    2/18/1957

IAH - HIGHEST DAILY PRECIPITATION FOR FEB 18TH
RANK  VALUE  ENDING DATE
  1    2.09    2/18/1938
**2    1.89    2/18/2012
  3    1.77    2/18/1963
  4    1.73    2/18/1924
  5    1.14    2/18/1946

HOU - HIGHEST DAILY PRECIPITATION FOR FEB 18TH
RANK  VALUE  ENDING DATE
**1    2.57    2/18/2012
  2    1.62    2/18/1963
  3    1.32    2/18/1946
  4    1.16    2/18/1949
  5    0.98    2/18/1957

GLS - HIGHEST DAILY PRECIPITATION FOR FEB 18TH
RANK  VALUE  ENDING DATE
**1    2.85    2/18/2012
  2    2.10    2/18/1924
  3    2.03    2/18/1946
  4    1.24    2/18/1990
  5    1.04    2/18/1963

BELOW ARE THE TABLES FOR THE WETTEST START TO THE YEAR FOR THE
SAME SITES.

RANKINGS FOR TOTAL RAINFALL BEGINNING JAN 1 THROUGH FEB 18 AND
WHERE WE STAND IN 2012.

CLL
RANK  VALUE  ENDING DATE
  1   17.28    2/18/1991
**2   12.08    2/18/2012
  3    9.96    2/18/1992
  4    9.58    2/18/2004
  5    9.04    2/18/1968

IAH
RANK  VALUE  ENDING DATE
  1   15.55    2/18/1891
  2   12.47    2/18/1934
  3   11.81    2/18/1991
  4   11.61    2/18/1908
  5   11.57    2/18/1992
**6   11.05    2/18/2012

HOU
RANK  VALUE  ENDING DATE
  1   12.35    2/18/1992
  2   12.32    2/18/1991,  2/18/1944
**4   12.20    2/18/2012
  5   11.38    2/18/1978

GLS
RANK  VALUE  ENDING DATE
  1   15.26    2/18/1991
  2   14.78    2/18/1992
  3   13.14    2/18/1899
  4   12.31    2/18/1993
  5   12.06    2/18/1923
**12  10.27    2/18/2012

$$

This is the wettest since the early 1990s. 1991 to 1994 was a wet period. 1991-1992 was a strong El Nino winter.

[Ptarmigan]

Friday is the arrival day for the trail riders. The 00Z WRF NMM suggests wet weather possible with a pesky upper low to our SW. We will see.

Hmmmmm, does this mean prolonged rains. Is this a cut-off low? If so, they can produce prolonged rains, like in summer of 2007.

[redneckweather]

Rain on Friday? Don't we have a front coming down Thursday night/Friday morning to clear everything out setting the stage for a beautiful weekend? I sure hope so.

[wxman57]

No prolonged rain period indicated. All models move the upper level trof through Thursday night/Friday morning then clear us out for the weekend. Looks reasonable.

Was biking from Stephen F. Austin through Bellville to Cat Spring and back to SFA on Saturday. Turned down Mill Creek Road out of Bellville and ran into the Salt Grass Trail Riders a few miles down the road. There were 26 wagons and hundreds of horses. We had to wait on the side of the narrow road for the trail riders to pass (30 min). Was an interesting diversion from our 57 mile ride.

[srainhoutx]

DAY 3 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0230 AM CST TUE FEB 21 2012

VALID 231200Z - 241200Z

...THERE IS A SLGT RISK OF SVR TSTMS FROM SRN AND ERN TX INTO A
PORTION OF THE SERN STATES...

...SYNOPSIS...

MODELS HAVE CONVERGED TO SIMILAR SOLUTIONS WITH REGARD TO EVOLUTION
OF SYNOPTIC PATTERN. BROAD UPPER TROUGH WILL REMAIN DOMINANT...AND
THIS FEATURE IS FORECAST TO AMPLIFY OVER THE MS VALLEY AS A STRONG
UPPER JET DROPS SEWD THROUGH THE INTERMOUNTAIN WEST...REACHING THE
SRN PLAINS TOWARD THE END OF THE PERIOD. MEANWHILE...SWLY LLJ WILL
STRENGTHEN OVER THE SERN STATES AND OH VALLEY IN ASSOCIATION WITH
THE AMPLIFYING NRN STREAM TROUGH. ECMWF HAS TRENDED TOWARD A SLOWER
EJECTION OF SRN STREAM UPPER LOW THAT WILL CUTOFF OVER NRN MEXICO
AND IS NOW SIMILAR TO THE GFS WITH THE NAM STILL BEING THE SLOWEST
MODEL. THE UPPER LOW WILL LIKELY REACH SRN TX LATER THURSDAY NIGHT.
AT THE SURFACE PRIMARY CYCLONE IS FORECAST TO CONSOLIDATE OVER THE
OH VALLEY OR GREAT LAKES WHILE A TRAILING COLD FRONT ADVANCES SEWD
THROUGH THE SRN PLAINS...LOWER MS VALLEY AND INTO WRN PORTIONS OF
THE SERN STATES.

...SERN STATES...

POTENTIAL FOR SIGNIFICANT SEVERE WEATHER WILL EXIST THURSDAY EVENING
AND OVERNIGHT.

STRENGTHENING SWLY BOUNDARY LAYER WINDS WILL CONTRIBUTE TO NEWD
TRANSPORT OF MODIFYING GULF AIR WITH DEWPOINTS FROM THE UPPER 60S
OVER SRN AND ERN TX INTO THE GULF COASTAL STATES TO NEAR 50 OVER SRN
PORTIONS OF THE OH VALLEY. GREATEST INSTABILITY WILL LIKELY DEVELOP
OVER THE LOWER MS VALLEY REGION JUST AHEAD OF THE FRONT WHERE PLUME
OF STEEPER LAPSE RATES WILL ADVECT EWD AND OVERTAKE THE WRN EDGE OF
THE MOIST AXIS. MLCAPE IN THIS REGION COULD RANGE FROM 1000-1500
J/KG. HOWEVER...THE RETURNING LOW LEVEL MOISTURE MIGHT CONTRIBUTE TO
THE DEVELOPMENT OF CLOUDS OVER A PORTION OF THIS REGION...AND THE
ATMOSPHERE WILL LIKELY REMAIN CAPPED TO SURFACE BASED CONVECTION
MUCH OF THE DAY. MODEL CONSENSUS IS THAT STORMS WILL DEVELOP BY
EARLY EVENING IN ZONE OF HEIGHT FALLS AND INCREASING FRONTAL
CONVERGENCE ASSOCIATED WITH THE AMPLIFYING WAVE AND STRENGTHENING
LLJ. ACTIVITY WILL EXIST WITHIN A STRONG KINEMATIC ENVIRONMENT AS
LLJ INCREASES TO IN EXCESS OF 50 KT WITH STRONG DEEP LAYER WINDS AND
VERTICAL SHEAR. THIS ENVIRONMENT WILL SUPPORT ORGANIZED STORMS
INCLUDING SUPERCELLS AND BOWING STRUCTURES WITH UPSCALE GROWTH
LIKELY OVERNIGHT. LARGE HAIL...DAMAGING WIND AND A FEW TORNADOES
WILL BE POSSIBLE AS STORMS DEVELOP EWD.


...OH VALLEY...

MOISTURE AND INSTABILITY WILL BE MORE LIMITED WITH NWD EXTENT INTO
THE OH VALLEY WITH MUCAPE AOB 500 J/KG LIKELY. FORCING WITHIN
FRONTAL ZONE WILL PROMOTE A LOW TOPPED LINE OF CONVECTION EMBEDDED
WITHIN STRONG VERTICAL SHEAR DURING THE AFTERNOON AND EVENING.
DESPITE THE LIMITED INSTABILITY SOME THREAT WILL EXIST FOR ISOLATED
DAMAGING WIND. LOW SEVERE PROBABILITIES HAVE BEEN INTRODUCED...BUT
AREA MAY NEED TO BE INCLUDED IN A SLIGHT RISK IN LATER OUTLOOKS.

...TX...

A FEW STORMS WILL PROBABLY DEVELOP ALONG SWRN EXTENSION OF THE FRONT
INTO ERN AND SRN TX WHERE STEEP LAPSE RATES AND A MOIST BOUNDARY
LAYER WILL PROMOTE MODERATE INSTABILITY. HOWEVER...THE ATMOSPHERE IN
THIS REGION WILL BE MORE CAPPED AND COVERAGE OF STORMS...ESPECIALLY
ACROSS SRN TX WILL BE MODULATED BY TIMING OF SRN STREAM WAVE. ANY
STORMS THAT DEVELOP WILL BE CAPABLE OF MAINLY ISOLATED DAMAGING WIND
AND HAIL.

..DIAL.. 02/21/2012

[srainhoutx]

No prolonged rain period indicated. All models move the upper level trof through Thursday night/Friday morning then clear us out for the weekend. Looks reasonable.

That pesky Winter Storm RECON data just seems to throw a monkey wrench into everything. Now the 12Z GFS has a showers with over running conditions on Saturday near Parade time.

[MontgomeryCoWx]

rain is rain... I'll take it.

[unome]

unfortunately, the thur/fri timing will make the bbq cook-off & trail rides a bit less enjoyable - it seems colder, wet weather always comes with the hlsr I hope everyone stays safe this year !

http://www.hlsr.com/events/bbq/index.aspx

http://www.rodeohouston.com/events/trai ... index.aspx

[wxman57]

12Z Euro doesn't agree with 12Z GFS - it ends the precip before noon Friday and forecasts a dry weekend for Houston. I think they may come to an agreement in the next 24 hours. Hopefully, that agreement will involve sunshine this weekend. But even the Euro isn't indicating a lot of sunshine.

[srainhoutx]

What's this the NWS Austin/San Antonio are mentioning? Wintry mischief?...lol

INTERESTING WINTER WEATHER SCENARIO MAY DEVELOP NEXT WEEK AS AN ARCTIC
AIR-MASS PLUNGES SOUTHWARD OVER THE REGION EARLY NEXT WEEK...STAY
TUNED. MODELS CANNOT RESOLVE THIS SHALLOW COLD AIR-MASS SO
TEMPERATURES WILL PARED DOWN CONSIDERABLY FROM GUIDANCE FOR A FIRST
SHOT AT THIS.

[Portastorm]

What's this the NWS Austin/San Antonio are mentioning? Wintry mischief?...lol

INTERESTING WINTER WEATHER SCENARIO MAY DEVELOP NEXT WEEK AS AN ARCTIC
AIR-MASS PLUNGES SOUTHWARD OVER THE REGION EARLY NEXT WEEK...STAY
TUNED. MODELS CANNOT RESOLVE THIS SHALLOW COLD AIR-MASS SO
TEMPERATURES WILL PARED DOWN CONSIDERABLY FROM GUIDANCE FOR A FIRST
SHOT AT THIS.

I'm at a loss to understand why they would write this. None of the models suggest such a scenario. Not even the cold-loving Canadian.

[srainhoutx]

What's this the NWS Austin/San Antonio are mentioning? Wintry mischief?...lol

INTERESTING WINTER WEATHER SCENARIO MAY DEVELOP NEXT WEEK AS AN ARCTIC
AIR-MASS PLUNGES SOUTHWARD OVER THE REGION EARLY NEXT WEEK...STAY
TUNED. MODELS CANNOT RESOLVE THIS SHALLOW COLD AIR-MASS SO
TEMPERATURES WILL PARED DOWN CONSIDERABLY FROM GUIDANCE FOR A FIRST
SHOT AT THIS.

I'm at a loss to understand why they would write this. None of the models suggest such a scenario. Not even the cold-loving Canadian.

Well the HPC is certainly 'interested' is something...

WEATHER RECONNAISSANCE FLIGHTS
CARCAH, NATIONAL HURRICANE CENTER, MIAMI, FL.
1130 AM EST TUE 21 FEBRUARY 2012
SUBJECT: WINTER STORM PLAN OF THE DAY (WSPOD)
VALID 22/1100Z TO 23/1100Z FEBRUARY 2012
WSPOD NUMBER.....11-084

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

II. PACIFIC REQUIREMENTS
1. FLIGHT ONE -- NOAA49 --
A. P55/ DROP 9 (45.0N 157.0W)/ 23/0000Z
B. NOAA9 23WSC TRACK55
C. 22/1930Z
D. 17 DROPS AS PUBLISHED ON TRACK
E. 41,000 TO 45,000 FT/ 23/0600Z

2. SUCCEEDING DAY OUTLOOK: POSSIBLE
TRACK P38/ DROP 9/ 24/00000Z

[wxman666]

Meanwhile, HGX seems to be frustrated and at a loss on the late week forecast for this week. Hopefully we'll see some better model agreement tomorrow. Even SPC sounds wishy washy, yet somehow confident at the same time. What a mess!

[srainhoutx]

Meanwhile, HGX seems to be frustrated and at a loss on the late week forecast for this week. Hopefully we'll see some better model agreement tomorrow. Even SPC sounds wishy washy, yet somehow confident at the same time. What a mess!

When you see a 36 hour spread, it does tend to be a tad frustrating with a end off week/weekend full of Rodeo activities. I've always said, stranger things have happened during trail ride season and Parade day...

PRECIP FCST IS SOMEWHAT FRUSTRATING. DEEPER MOISTURE OFFSHORE IS
FCST TO BE A BIT FURTHER SOUTH THAN EARLIER THINKING TOMORROW. IN
ADDITION...DON`T SEE ANY SIGNIFICANT IMPULSES TO TRIGGER PRECIP
NEARBY SO WENT AHEAD AND YANKED THE POPS OUT OF WEDS FCST. STILL
ANTICIPATE A COLD FRONT TO PUSH THRU SE TX LATE THURS NIGHT.
QUESTION IS WHERE WILL THE UPPER TROF AND ASSOCIATED PRECIP BE???
MODELS IN POOR AGREEMENT REGARDING THIS. ECMWF & CANADIAN MOST
PROGRESSIVE WITH GFS MUCH LESS SO. WE`RE TALKING 36 HOURS OR SO
DIFFERENT. NAM SOMEWHERE IN BETWEEN. THIS MAKES A DIFFERENCE AS TO
WHETHER TO EXPECT PRECIP MOSTLY AHEAD OF THE FRONT AND/OR BEHIND
IT. REALLY DON`T HAVE A STRONG FEEL ONE WAY OR THE OTHER AS EACH
OF THEIR ENSEMBLES STILL SUPPORT ITS OPERATIONAL RUN. BEST SOLUTION
WE COULD COME UP WITH IS TO BROADBRUSH LOWER END POPS THURS NIGHT
THRU SATURDAY. FAIRLY CONFIDENT WE`LL SO SOME RAINFALL AND UNDOUBTEDLY
POPS WILL PROBABLY HAVE TO BE SIGNIFICANTLY RAISED DURING ONE OF
THE TIME PERIODS AND REMOVED FROM THE OTHERS AS THE SOLN BECOMES
MORE CLEAR.

[srainhoutx]

I'm thinking that recon is for a storm which hits the Pac NW Friday.

And that would be a wrong assumption. Current guidelines for tasking NOAA G-IV flights are extremely limited due to budget constraints and any mission tasked for those G-IV flights require data sampling beyond one specific regional impact. In other words, the HPC will only request tasking for a storm complex with much broader implications than that of the Pacific NW. C-130 flights out of AK are a bit different. Those missions are DoD funded and fly much more frequently that the expensive G-IV flights out of HI.

[wxman57]

What's this the NWS Austin/San Antonio are mentioning? Wintry mischief?...lol

INTERESTING WINTER WEATHER SCENARIO MAY DEVELOP NEXT WEEK AS AN ARCTIC
AIR-MASS PLUNGES SOUTHWARD OVER THE REGION EARLY NEXT WEEK...STAY
TUNED. MODELS CANNOT RESOLVE THIS SHALLOW COLD AIR-MASS SO
TEMPERATURES WILL PARED DOWN CONSIDERABLY FROM GUIDANCE FOR A FIRST
SHOT AT THIS.

I'm at a loss to understand why they would write this. None of the models suggest such a scenario. Not even the cold-loving Canadian.

I agree - I can't see anything of an Arctic airmass coming down to Texas next week.

[srainhoutx]

Morning e-mail from Jeff:

Warmth prevails ahead of the next cold front slated for Thursday night.

High pressure over the Gulf of Mexico and lowering pressures over the central plains will support a general southerly wind flow for the next 36 hours ahead of the next cold front. SSW to SW flow in the mid levels will effectively cap the region off as very warm mid level temperatures advect ENE from the higher terrain of northern MX. Next fairly decent intensity cold front will cross the area late Thursday night or early Friday morning and while there will be favorable parameters for thunderstorms with this front, do not think the warm mid levels will be overcome….thus a fairly low rain chances. While SPC has placed the SE part of our area under a severe threat, feel the best chances will be NE over central LA and eastward where a fairly significant severe weather event is possible. With that said, the global models are having a very hard time with the upper trough over NW MX and when/where/ and at what intensity it moves across TX. Yesterday models were in a little better agreement that the trough might cross close to the frontal passage time frame helping to erode the capping inversion and increase the threat of thunderstorms, now the models have slowed down the ejection of this system and shifted in further southward. Upstream jet stream patterns across the Pacific are fast and progressive and this should help eject this system out, but likely post frontal passage. This will help keep clouds in place on Friday with very cool conditions (highs near 60) compared to today and tomorrow (highs near 80). I am not overly impressed with the rain chances as most of the energy looks south of our region out over the Gulf and from the coastal bend southward. There is low confidence in the late week into the weekend forecast and some changes mainly with increasing rain chances are possible during the Friday-Saturday period should the Baja system eject northward some.

Cool weather will be in place through the weekend before the next system begins to evolve over the SW US and strong warm air advection returns early next week. A chances of showers and thunderstorms will return at this point with temperatures warming again. Longer range models show a fairly wet and cool pattern for the last week of Feb into early March with potential for shallow cold air mass to be overrun on both Gulf and Pacific moisture.

SPC Day 2 (Thursday) Severe Weather Outlook:

[wxman57]

The good, the bad and the ugly, according to the 06Z GFS run raw data:

[MontgomeryCoWx]

My graph would be an inverse. 82 degrees is just butt ugly.

[wxman57]

I think that 85F is just about the perfect temperature for any season. It's warm enough that I don't get a little cool while biking (with a 15-25 mph wind blowing on my wet skin), which can happen at a temperature closer to 80F. Too bad I won't get out on my bike tomorrow.

12Z GFS coming in now. I'm growing confident that we won't be seeing another freeze this season.