Jump to content
  • Member Statistics

    17,508
    Total Members
    7,904
    Most Online
    joxey
    Newest Member
    joxey
    Joined

Texas/New Mexico/Louisiana/Mexico Obs And Discussion Thread Part 5


wxmx

Recommended Posts

  • Replies 1.9k
  • Created
  • Last Reply

The first day of March looks very chilly as another cold front passes Texas early Friday. The fly in the ointment that has been present for several days via the GFS/Euro/Ukmet is a vort max/strong short wave diving due S from the Plains and will cross our Forecast area mainly W of the I-45 Corridor to the Coastal Bend late Friday afternoon/early Saturday. The forecast soundings indicate very cold air aloft with just enough lift and a saturated column with our area in a favorable left front quadrant to generate some moisture. HGX has mentioned the possibility of some of this moisture making it to the surface. The temp profiles throughout the column indicate light snow/snow flurries are possible during the overnight hours. Surface temps appear to be border line or just above freezing, but due to the strong cold air advection over the heavy snow pack to our N from the Blizzard earlier this week it may be worth monitoring. The one issue that will have to be overcome is a very dry layer below 3000 to 5000 feet. While HGX is mentioning that enough saturation may occur, my hunch is that virga will be the most likely outcome with maybe a flurry or two reaching the ground. It is interesting to note the the NOAA G-IV is scheduled to make some drops as it departs Hawaii on its return flight to their home base in Tampa overnight. Saturday looks cloudy and cold as temps struggle to reach the mid 50's with freezing to near freezing temps expected away from the urban heat island areas overnight Saturday/early Sunday.

Link to comment
Share on other sites

Afternoon e-mail from Jeff:

 

Secondary surge of high pressure has crossed the region this afternoon with an increase in NW winds and advection of another dry air mass. Very little change in the pattern over the next few days as dry NW flow aloft remains in place with another frontal passage on Friday afternoon.

 

Friday afternoon frontal passage will usher in a cold air mass with sub-freezing 850mb temperatures all the way to the coast. Model guidance suggest a very strong upper air disturbance rides down the backside of the main eastern US trough across the heart of TX late Friday night into Saturday morning. The air mass over the region will be very dry in the low levels, but strong lift along with cold temperatures aloft could generate favorable conditions for a few flurries especially around Matagorda Bay where moisture will be the greatest. Current thinking is pointing toward a very dry surface layer with most of what falls evaporating before hitting the ground. Latest GFS has trended drier with the short wave with any chance of flurries less than 20%.
 
As for temperatures, dewpoints falling into the upper 20’s and lower 30’s will support surface temperatures near freezing both Saturday and Sunday mornings mainly north of I-10 and away from the major urban heat cores. Still with spring green up in progress already, some tender vegetation could get burned if not protected.
 
Otherwise cool and dry for the next 5-7 days. 

Link to comment
Share on other sites

We have light frost up here in NW Harris County this morning. The feature outlined by the SPC for today for locations across Southern Oklahoma and North Central Texas is what is creating the fuss about this potential snow flurry/ice pellet talk that has been mentioned most of the week. We will see what the radar suggests later today to see if there is anything to this novelty potential that HGX has been talking about the past 5 days.

 

DAY 1 CONVECTIVE OUTLOOK 
   NWS STORM PREDICTION CENTER NORMAN OK
   0617 AM CST FRI MAR 01 2013
  
   VALID 011300Z - 021200Z
  
   ...NO SVR TSTM AREAS FORECAST...
  
   ...SYNOPSIS AND FORECAST...
  
   THE PRIMARY FEATURES OF INTEREST DURING THE DAY 1 PERIOD ARE MID AND
   UPPER-LEVEL JET STREAKS AND AN ASSOCIATED MIDLEVEL VORTICITY MAXIMUM
   WHICH WILL DEVELOP EQUATORWARD THROUGH THE HIGH PLAINS TODAY IN
   TANDEM WITH A WEAK SURFACE TROUGH.  DAYTIME HEATING COUPLED WITH A
   POCKET OF COLD MIDLEVEL TEMPERATURES /AND STEEP LAPSE RATES -- SEE
   THE 12Z DDC SOUNDING/ ATTENDING THE VORTICITY MAXIMUM WILL YIELD A
   MARGINALLY UNSTABLE ENVIRONMENT OVER PORTIONS OF THE RED RIVER
   VALLEY OF OK/TX WITH SBCAPE VALUES OF 100-200 J/KG.  MODEL-DERIVED
   SOUNDINGS SUGGEST THAT CONVECTION DEVELOPING ALONG THE SURFACE WIND
   SHIFT WILL BE RELATIVELY SHALLOW...BUT SUFFICIENTLY DEEP FOR
   SPORADIC LIGHTNING PRODUCTION THIS AFTERNOON INTO EVENING.
  
   ..MEAD/JIRAK.. 03/01/2013

post-32-0-27676500-1362143342_thumb.gif

Link to comment
Share on other sites

light frost in CLL in the am.

 

supercooling with a ULL and verga above descending from the N...possible freeze tonight

 

 

AREA FORECAST DISCUSSIONNATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX326 PM CST FRI MAR 1 2013.DISCUSSION...WILL CONTINUE TO CARRY VERY LOW POPS OVERNIGHT FOR MAINLY OUR SOUTHWESTCOUNTIES...BUT EXPECT THE MAJORITY OF RADAR ECHOES GENERATED BY THISMID/UPPER LEVEL DISTURBANCE THAT WILL BE MOVING ACROSS THE AREA FROMTHE NORTH TO EVAPORATE BEFORE REACHING THE GROUND. A COLD FRONT THATWILL MOVE THROUGH THE AREA AND OFF THE COAST OVERNIGHT WILL BRING ANEND TO THESE SLIM EARLY WEEKEND PRECIP CHANCES. THE REST OF THE FORECASTPACKAGE WILL BE MAINLY A TEMPERATURES FORECAST. DESPITE EXPECTED FULLSUNSHINE...SATURDAY WILL REMAIN ON THE COOL SIDE WITH HIGHS IN THE 50SUNDER NORTH WINDS RUNNING 10 TO 20 MPH. SURFACE HIGH PRESSURE SETTLINGINTO THE AREA SATURDAY NIGHT THRU SUNDAY MORNING WILL RESULT IN SEVERALHOURS OF FREEZING TEMPERATURES ROUGHLY NORTH OF INTERSTATE 10...ANDWE MIGHT END UP NEEDING TO ISSUE A LATE SEASON FREEZE WARNING FOR PORTIONSOF OUR AREA EITHER OVERNIGHT TONIGHT OR DURING THE DAY TOMORROW. FORNOW...WILL CONTINUE TO HIGHLIGHT THIS IN OUR HAZARDOUS WEATHER OUTLOOK.
Link to comment
Share on other sites

Morning e-mail from Jeff:

 

Wind Advisory in effect today
 
Red Flag Warning in effect today.

 

Strong cold front currently crossing the area will bring very strong winds to the region today. Tight pressure gradient noted over central TX this morning will spill southward over the next few hours with winds rapidly increasing into the 20-35mph range behind a cold front. By mid morning mixing of stronger winds aloft toward the surface will result in wind gust to 40-45mph.
 
Given the very dry air moving into the region from the north combined with the strong and gusty winds, near critical fire weather conditions are expected from late morning through late afternoon. Fine fuels (grasses) continue to dry with a lack of recent rainfall and some areas especially west of I-45 and north of I-10 have yet to see significant spring green up increasing the potential for wildfire. Should a wildfire develop, strong winds will result in rapid and erratic growth and fast forward burn rates. Conditions appear most dangerous west of I-45 where the lowest RH and strongest winds will be found. Very critical fire weather conditions will be found over much of central TX into the coastal bend where several fires developed last Friday with more marginal conditions.

 

Dry and cold air mass will cover the region tonight with high pressure building overhead winds will weaken but not likely go calm. Lows will average in the mid to upper 30’s for most areas. High pressure slowly moves eastward allowing a return of SE winds by late Friday and a slow but steady warming/moistening trend through the weekend. NW upper level flow of late becomes increasingly more SW with time opening the door to disturbances moving NE out of MX and possibly interacting with increasing moisture to produce a few showers.

Link to comment
Share on other sites

After a quiet week in the weather department and daily lack of guidance continuity, the Winter RECON data from the Pacific appears to have paid some dividends and finally settled the computer models down over night. While we have seen many times this year so far those models paint rain and storm chance for our Region that have left us lacking with rainfall, perhaps this storm system will bode a bit better for our drought parched area.

 

What makes the next storm system a bit more challenging and hopeful that most areas will benefit from rains and storms is the dual ejection process of a 500mb upper low and attending surface low with embedded disturbances riding the Sub Tropical Jet along a SW to NE oriented positive tilted upper trough that hangs back into Northern Mexico. Winds will begin to switch E and then ESE to SE today as high pressure that has brought quiet weather other than passing high clouds across the region moves E and the Gulf opens for business. The return flow off the Gulf and increasing moisture along with moderating temps should set the stage for warming temps and increasing low level moisture flow as pressures fall to our W. The SPC has outlined a Slight Risk for late Friday as well as Saturday for areas of the Panhandle extending SE into the Hill Country on Saturday. What make this storm complex a bit different is that it will not be fast moving, nor a skinny line of showers that races across the Region. The slower progression of the long wave pattern may offer a better chance at some much needed rain with the best chances Saturday for Central Texas and Sunday for NE/E/SE Texas as a line of storms finally clears the area and we dry out once again as a zonal flow pattern returns. The fly in the ointment may be that the Pacific front may hang up near the Coast late Sunday increasing rain and storm chances for Louisiana. Fingers crossed this storm will fair better in the rainfall department all of our Region than we have experienced thus far this year.

 

Link to comment
Share on other sites

HYDROLOGIC OUTLOOK
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
430 PM CST THU MAR 7 2013

...SPRING FLOOD OUTLOOK FOR SOUTH CENTRAL TEXAS...

...BELOW AVERAGE POTENTIAL FOR SPRING FLOODING FOR ALL RIVERS AND
CREEKS IN THE AUSTIN/SAN ANTONIO HYDROLOGIC SERVICE AREA...

FOR THE SPRING OF 2013...THE WEST GULF COAST RIVER FORECAST CENTER
IS FORECASTING A BELOW AVERAGE POTENTIAL FOR SPRING FLOODING OVER
ALL RIVERS AND CREEKS IN THE AUSTIN/SAN ANTONIO HYDROLOGIC SERVICE
AREA (HSA). THIS INCLUDES THE FOLLOWING BASINS...COLORADO RIVER...
BRAZOS RIVER...SAN MARCOS RIVER...GUADALUPE RIVER...SAN ANTONIO
RIVER...MEDINA RIVER...NUECES RIVER...FRIO RIVER AND THE RIO GRANDE.

EXISTING CONDITIONS...

DROUGHT...ABNORMALLY DRY CONDITIONS WERE NOTED ACROSS A SMALL
PORTION OF SOUTH CENTRAL TEXAS. THE MAJORITY OF THE HYDROLOGIC
SERVICE AREA (HSA) IS CURRENTLY IN MODERATE TO EXCEPTIONAL DROUGHT.
EXTREME TO EXCEPTIONAL DROUGHT CONDITIONS CONTINUE ACROSS THE RIO
GRANDE PLAINS AND WESTERN HILL COUNTRY.

SOIL MOISTURE...DRY TO VERY DRY SOILS ARE PRESENT OVER THE ENTIRE
HYDROLOGIC SERVICE AREA (HSA). THE GREATEST ANOMALIES WERE NOTED
OVER THE RIO GRANDE PLAINS. WITH VERY DRY CONDITIONS FOR THE LAST
SEVERAL YEARS THE SOILS WILL BE ABLE TO HANDLE MOST RAINFALL
EVENTS WITHOUT SIGNIFICANT FLOODING. IF RAINFALL AMOUNTS WERE TO
BECOME EXCESSIVE THEN A THREAT WOULD EXIST FOR RIVER FLOODING.

STREAMFLOW...DURING THE FALL AND WINTER STREAMFLOWS HAVE REMAINED
BELOW TO MUCH BELOW NORMAL. A COUPLE OF RAINFALL EVENTS DID CAUSE
A FEW RISES TO BANKFULL AND MINOR FLOODING...BUT THESE WERE MOSTLY
IN THE URBAN AREAS. THE RIO GRANDE HAS SEEN A COUPLE OF PERIODS
WITH INCREASED STREAMFLOW...BUT THIS WAS THE RESULT OF MANDATED
RELEASES FROM LAKE AMISTAD AND HYDRO ELECTRIC POWER GENERATION.

RESERVOIR CONDITIONS...RESERVOIRS AND LAKES ACROSS THE HYDROLOGIC
SERVICE AREA (HSA) REMAIN VERY LOW AND HAVE NOT REALLY SEEN ANY
IMPROVEMENTS OVER THE FALL AND WINTER. MEDINA LAKE IS CURRENTLY
THE LOWEST LAKE IN THE REGION AND STANDS AT 7.5 PERCENT OF
CAPACITY AND IS 76.8 FEET BELOW THE NORMAL POOL. LAKE AMISTAD AND
LAKE TRAVIS REMAIN NEAR 50 FEET BELOW THE NORMAL POOL ELEVATIONS.
WITH THESE EXTREMELY LOW LEVELS IT WILL BE DIFFICULT TO GET THESE
VALUES BACK TO NORMAL POOL.

RAINFALL...RAINFALL WAS SPORADIC DURING THE FALL AND WINTER WITH
MOST LOCATIONS REPORTING BELOW OR WELL BELOW AVERAGE RAINFALL.
THE REGION HAS SEEN A FEW RAINFALL EVENTS THAT PRODUCED WIDESPREAD
RAINFALL AND AMOUNTS OF TO INCHES OR MORE...BUT THE LONG DRY
PERIODS BETWEEN EVENTS AND THE DRY CONDITIONS FROM THE LAST 12 TO
18 MONTHS HAVE CAUSED CONDITIONS TO REMAIN DRY DESPITE THE RAIN.
THE RIO GRANDE...NUECES AND FRIO RIVER BASINS HAVE SEEN THE LEAST
AMOUNT OF RAINFALL DURING THE LAST 12 TO 18 MONTHS.

CLIMATE REGIME...AN ENSO (EL-NINO SOUTHERN OSCILLATION) NEUTRAL
PATTERN HAS EXISTED OVER THE EQUATORIAL PACIFIC OCEAN DURING THE
FALL AND WINTER. RAINFALL OVER THE HSA HAS BEEN MORE
REPRESENTATIVE OF A LA-NINA EPISODE WITH BELOW NORMAL RAINFALL
OVER MOST AREAS. THE CLIMATE PREDICTION CENTER (CPC) HAS NOTED
THAT THE ATMOSPHERIC CIRCULATION AT TIMES HAS RESEMBLED LA
NINA...AT LEAST PARTIALLY DUE TO AN ACTIVE MADDEN-JULIAN
OSCILLATION (MJO). SEA SURFACE TEMPERATURES ACROSS THE EQUATORIAL
PACIFIC OCEAN ARE NEAR TO SLIGHTLY BELOW AVERAGE. THE CPC EXPECTS
ENSO NEUTRAL CONDITIONS NOW TO LAST THROUGH THE NORTHERN
HEMISPHERE SUMMER OF 2013. AS A RESULT...THE PROSPECTS FOR A
PROLONGED WET PERIOD LEADING TO A WET SPRING APPEARS UNLIKELY.

METEOROLOGICAL OUTLOOK...
THE CLIMATE PREDICTION CENTER (CPC) MONTHLY AND THREE-MONTH
OUTLOOKS FOR THE REMAINDER OF SPRING (MARCH/APRIL/MAY) AND INTO
SUMMER (JUNE/JULY/AUGUST) CONTINUE TO SHOW GREATER TRENDS FOR
ABOVE AVERAGE TEMPERATURES AND BELOW AVERAGE RAINFALL. THE LATEST
DROUGHT OUTLOOK ALSO SHOWS DROUGHT CONDITIONS CONTINUING (OR
INTENSIFYING) OVER CURRENT DROUGHT AREAS...WITH DROUGHT CONDITIONS
DEVELOPING OVER AREAS NOT CURRENTLY IN DROUGHT.

...SPRING FLOOD OUTLOOK...
AFTER SEVERAL YEARS OF DROUGHT AND WELL BELOW NORMAL SOIL MOISTURE
CONDITIONS...LOW STREAM FLOWS AND THE VERY LOW LAKE AND RESERVOIRS
LEVELS...THE POTENTIAL FOR SPRING FLOODING DURING 2013 IS BELOW
AVERAGE.

REFERENCES/LINKS:

PRECIPITATION ANALYSIS:
HTTP://WATER.WEATHER.GOV/PRECIP/

STREAMFLOW CONDITIONS: HTTP://WATERDATA.USGS.GOV/NWIS/RT
HTTP://WWW.DWR.STATE.CO.US/SURFACEWATER/DEFAULT.ASPX

RESERVOIR SUMMARIES:
HTTP://WWW.WCC.NRCS.USDA.GOV/WSF/RESERVOIR/RESV_RPT.HTML
HTTP://WIID.TWDB.TEXAS.GOV/IMS/RESINFO/BUSHBUTTON/LAKESTATUS.ASP
HTTP://WATERDATAFORTEXAS.ORG/RESERVOIRS/STATEWIDE

SOIL MOISTURE CONDITIONS:
HTTP://WWW.CPC.NCEP.NOAA.GOV/PRODUCTS/SOILMST_MONITORING/US/SOILMST/SOILMST.
SHTML

US DROUGHT MONITOR AND OUTLOOK:
HTTP://WWW.DROUGHT.UNL.EDU/DM/MONITOR.HTML
HTTP://WWW.CPC.NOAA.GOV/PRODUCTS/EXPERT_ASSESSMENT/SEASON_DROUGHT.GIF'>HTTP://WWW.CPC.NOAA.GOV/PRODUCTS/EXPERT_ASSESSMENT/SEASON_DROUGHT.GIF

TX DROUGHT INFORMATION:
HTTP://WWW.TWDB.STATE.TX.US/APPS/DROUGHTINFO/ALLMAPVIEW.ASPX

CLIMATE GRAPHICS:
HTTP://WWW.CPC.NOAA.GOV/
HTTP://WWW.CPC.NOAA.GOV/PRODUCTS/PREDICTIONS/LONG_RANGE/LEAD01/OFF01_TEMP.GIF
HTTP://WWW.CPC.NOAA.GOV/PRODUCTS/PREDICTIONS/LONG_RANGE/LEAD01/OFF01_PRCP.GIF

LOCAL WEATHER...RIVER...CLIMATE AND FORECAST INFORMATION FOR
SOUTH CENTRAL TEXAS:
HTTP://WWW.SRH.WEATHER.GOV/EWX


 

Link to comment
Share on other sites

HYDROLOGIC OUTLOOK
NATIONAL WEATHER SERVICE CORPUS CHRISTI TX
1134 AM CST THU MAR 7 2013

...SPRING FLOOD OUTLOOK FOR THE COASTAL BEND AND RIO GRANDE PLAINS...

...BELOW AVERAGE POTENTIAL FOR SPRING FLOODING FOR ALL RIVERS AND
CREEKS IN THE CORPUS CHRISTI HYDROLOGIC SERVICE AREA...

FOR THE SPRING OF 2013...THE WEST GULF COAST RIVER FORECAST
CENTER IS FORECASTING A BELOW AVERAGE POTENTIAL FOR SPRING
FLOODING OVER ALL RIVERS AND CREEKS IN THE CORPUS CHRISTI
HYDROLOGIC SERVICE AREA (HSA). THIS INCLUDES THE FOLLOWING
BASINS...GUADALUPE RIVER...SAN ANTONIO RIVER...RIO GRANDE...
NUECES RIVER...FRIO RIVER...MISSION RIVER...ATASCOSA RIVER AND ALL
COASTAL CREEKS.


EXISTING CONDITIONS...
DROUGHT...AT LEAST THREE QUARTERS OF THE HSA IS IN AT LEAST A
MODERATE DROUGHT...WITH ALL OF THE HSA IN AT LEAST ABNORMALLY DRY
CONDITIONS. MOST OF THE RIO GRANDE BASIN IS IN EXTREME
DROUGHT...WITH THE UPPER NUECES...FRIO...AND GUADALUPE RIVER
BASINS (OUTSIDE OF THE HSA) IN MODERATE TO SEVERE DROUGHT STATUS.
OSO AND SAN FERNANDO CREEKS ARE IN EXCEPTIONAL DROUGHT STATUS...AS
A RESULT OF EXTREMELY HIGH RAINFALL DEFICITS OVER THE PAST TWO
YEARS.

SOIL MOISTURE...DRY TO VERY DRY SOILS ARE PRESENT OVER THE ENTIRE
HYDROLOGIC SERVICE AREA (HSA)...WITH THE GREATEST ANOMALIES OVER
THE SOUTHERN COASTAL BEND AND BRUSH COUNTRY. THUS...WITH VERY LOW
SOIL MOISTURE VALUES...THE GROUND HAS A LARGE CAPACITY TO HOLD A
GOOD DEAL OF RAINFALL (UNLESS RAINFALL RATES BECOME EXCESSIVE).

STREAMFLOW...DURING THE PAST SEVERAL MONTHS...RIVER LEVELS ON THE
RIO GRANDE WERE ABOVE NORMAL AT TIMES...DUE TO RELEASES FROM LAKE
AMISTAD. OTHERWISE...RIVER AND CREEK LEVELS HAVE BEEN BELOW TO WELL
BELOW NORMAL OVER NEARLY ALL OF THE HSA FOR SOME TIME. THIS HAS
BEEN ESPECIALLY TRUE FOR THE GUADALUPE...FRIO...ATASCOSA...AND
MISSION RIVER BASINS. AT THIS TIME...NEAR NORMAL FLOWS WERE
OBSERVED ON THE ARANSAS AND SAN ANTONIO RIVERS...AS WELL AS OSO
CREEK...AND LOCATIONS SOUTH OF THE RESERVOIRS. THE ONLY RECENT
FLOODING OBSERVED WAS ON THE ARANSAS RIVER IN EARLY FEBRUARY...
WHICH LASTED ONLY A FEW HOURS. OTHERWISE...RIVERS AND CREEKS HAVE
BEEN RUNNING BELOW AVERAGE FOR MOST OF THE LAST SEVERAL MONTHS.

RESERVOIR CONDITIONS...POOL LEVELS FOR CHOKE CANYON DAM AND LAKE
CORPUS CHRISTI ARE VERY LOW...ESPECIALLY THE LATTER WHICH HAS BEEN
WELL BELOW 20 PERCENT POOL CAPACITY FOR MONTHS. LAKE AMISTAD IS
AROUND 30 PERCENT OF CAPACITY...WITH CANYON DAM AROUND 81 PERCENT
OF CAPACITY. AS OF MARCH 7...THE PERCENT CAPACITY WAS 45.5
PERCENT AT CHOKE CANYON...15.2 PERCENT AT LAKE CORPUS CHRIST...AND
86.1 PERCENT AT LAKE TEXANA. COLETO CREEK IS ABOUT 2.7 FEET BELOW
NORMAL POOL LEVEL. THUS...ANY EXCESSIVE RAINFALL UPSTREAM OF THE
RESERVOIRS WILL HELP TO REPLENISH RESERVOIR LEVELS...SINCE THE
POTENTIAL FOR RESERVOIRS TO REACH OR EXCEED POOL CAPACITY LEVELS
IS RATHER LOW.

RAINFALL...DURING THE LAST 6 MONTHS...RAINFALL DEFICITS HAVE BEEN
OBSERVED OVER MOST OF SOUTH TEXAS...WITH MOST AREAS RECEIVING NO
MORE THAN 75 PERCENT OF THEIR NORMAL RAINFALL SINCE EARLY
SEPTEMBER 2012. THE ONLY LOCATIONS WHICH RECEIVED ABOVE NORMAL
RAINFALL WERE OVER SMALL PORTIONS OF THE NUECES AND FRIO RIVER
BASINS. THE COASTAL CREEK BASINS HAVE BEEN ESPECIALLY DRY...WITH
THE SAN FERNANDO AND OSO CREEK BASINS RECEIVING LESS THAN 50
PERCENT OF THEIR NORMAL RAINFALL SINCE EARLY SEPTEMBER 2012.

CLIMATE REGIME...ALTHOUGH ENSO (EL-NINO SOUTHERN OSCILLATION)
NEUTRAL CONDITIONS HAVE EXISTED OVER THE EQUATORIAL PACIFIC
OCEAN DURING THE PAST SEVERAL MONTHS...RAINFALL OVER THE HSA HAS
BEEN MORE REPRESENTATIVE OF A LA-NINA EPISODE (I.E. BELOW NORMAL
RAINFALL OVER MOST AREAS). IN FACT...THE CLIMATE PREDICTION CENTER
(CPC) HAS NOTED THAT THE ATMOSPHERIC CIRCULATION AT TIMES HAS
RESEMBLED LA NINA...AT LEAST PARTIALLY DUE TO AN ACTIVE MADDEN-
JULIAN OSCILLATION (MJO). SEA SURFACE TEMPERATURES ACROSS THE
EQUATORIAL PACIFIC OCEAN ARE NEAR TO SLIGHTLY BELOW AVERAGE. THE
CPC EXPECTS ENSO NEUTRAL CONDITIONS NOW TO LAST THROUGH THE
NORTHERN HEMISPHERE SUMMER OF 2013. AS A RESULT...THE PROSPECTS
FOR A VERY PERSISTENT...WET SPRING APPEAR UNLIKELY.

METEOROLOGICAL OUTLOOK...BOTH THE MONTHLY AND THREE-MONTH
TEMPERATURE AND PRECIPITATION OUTLOOKS FOR MARCH AND MARCH
THROUGH MAY...RESPECTIVELY...SHOW A GREATER LIKELIHOOD FOR BELOW
NORMAL RAINFALL AND ABOVE NORMAL TEMPERATURES. THE THREE MONTH
OUTLOOK FOR THE APRIL-MAY-JUNE PERIOD ALSO CALLS FOR A GREATER
LIKELIHOOD FOR BELOW NORMAL RAINFALL AND ABOVE NORMAL TEMPERATURES.
THE LATEST DROUGHT OUTLOOK ALSO SHOWS DROUGHT CONDITIONS
CONTINUING (OR INTENSIFYING) OVER CURRENT DROUGHT AREAS...WITH
DROUGHT CONDITIONS DEVELOPING OVER AREAS NOT CURRENTLY IN DROUGHT.
AS A RESULT...CHANCES FOR PERSISTENT OR FREQUENT HEAVY RAINFALL
WHICH COULD RESULT IN FLOODING ARE LOW AT THIS TIME.


...SPRING FLOOD OUTLOOK...
DUE TO THE BELOW NORMAL SOIL MOISTURE CONDITIONS...THE CAPACITY OF
THE RESERVOIRS TO HOLD ANY EXCESSIVE RAINFALL UPSTREAM...THE
OVERALL LOW STREAMFLOW LEVELS...AND CLIMATE OUTLOOKS THROUGH
JUNE...THE POTENTIAL FOR SPRING FLOODING DURING 2013 IS BELOW
AVERAGE.

 

 

 

Link to comment
Share on other sites

HYDROLOGIC OUTLOOK
NATIONAL WEATHER SERVICE LAKE CHARLES LA
1032 AM CST THU MAR 7 2013

...SPRING FLOOD POTENTIAL OUTLOOK FOR SOUTHEAST TEXAS...SOUTHWEST
AND CENTRAL LOUISIANA...

INTRODUCTION...

THIS IS THE 2013 SPRING FLOOD POTENTIAL OUTLOOK ISSUED BY THE
NATIONAL WEATHER SERVICE IN LAKE CHARLES LOUISIANA. THIS ISSUANCE
OUTLINES CURRENT RIVER AND SOIL MOISTURE CONDITIONS AND HIGHLIGHTS
POTENTIAL SITUATIONS THAT COULD INDUCE FLOODING.

ANTECEDENT CONDITIONS...

SINCE THE BEGINNING OF THE WATER YEAR OCTOBER 1 2012...ALL OF EAST
TEXAS AND WESTERN LOUISIANA REMAIN BELOW NORMAL RAINFALL...WHILE
CENTRAL AND SOUTH CENTRAL LOUISIANA HAVE EXPERIENCED NORMAL TO
SLIGHTLY ABOVE NORMAL PRECIPITATION. MEANWHILE...FOR METEOROLOGICAL
WINTER...DECEMBER THROUGH FEBRUARY...THE REGION EXPERIENCED ABOVE
TO MUCH ABOVE NORMAL RAINFALL ACROSS SOUTHWEST AND CENTRAL
LOUISIANA. SOUTHEAST TEXAS HAD NORMAL TO SLIGHTLY BELOW NORMAL
PRECIPITATION. OVER THE PAST 30 DAYS RAINFALL AMOUNTS HAVE
GENERALLY BEEN BELOW NORMAL ACROSS EAST TEXAS WITH NEAR NORMAL
RAINFALL ACROSS CENTRAL AND SOUTH CENTRAL LOUISIANA.

ACCORDING TO THE US GEOLOGICAL SURVEY (USGS)...CURRENT STREAM
FLOW CONDITIONS ACROSS SOUTHEAST TEXAS USING A 28 DAY AVERAGE
SHOW BELOW NORMAL TO NORMAL STREAM FLOW CONDITIONS...WHILE 28 DAY
AVERAGE STREAM FLOWS IN SOUTHWEST AND CENTRAL LOUISIANA ARE NEAR
NORMAL TO SLIGHTLY ABOVE NORMAL.

THE US DROUGHT MONITOR INDICATES THAT NO AREAS ARE CURRENTLY IN
DROUGHT...HOWEVER PORTIONS OF SOUTHEAST TEXAS ARE NOTED AS BEING
ABNORMALLY DRY.

METEOROLOGICAL OUTLOOK...
THERE IS ONE STORM SYSTEM FORECAST TO MOVE ACROSS THE REGION OVER
THE NEXT 10 DAYS. THIS STORM SYSTEM IS FORECAST TO PRODUCE AN
AVERAGE ONE TO TWO INCHES OF RAINFALL.

CLIMATOLOGICAL OUTLOOK...

TYPICALLY IN THE SPRING...PRECIPITATION AMOUNTS DECLINE ALONG THE
COAST AND INCREASE INLAND.

THE CURRENT CLIMATE OUTLOOK FROM THE CLIMATE PREDICTION CENTER FOR
THE REMAINDER OF MARCH INDICATES EQUAL CHANCES OF HAVING
ABOVE...BELOW AND NORMAL TEMPERATURES AND PRECIPITATION. WHILE THE
OUTLOOK FOR THE NEXT THREE MONTHS INDICATE A GREATER THAN 50
PERCENT CHANCE OF ABOVE NORMAL TEMPERATURES AND A GREATER THAN 33
PERCENT CHANCE OF BELOW NORMAL PRECIPITATION.

THERE ARE ALSO INDICATIONS THAT DROUGHT CONDITIONS MAY CREEP BACK
INTO PORTIONS OF SOUTHEAST TEXAS.

RIVER BASIN HYDROLOGIC OUTLOOK...

...NECHES AND SABINE RIVERS AND TRIBUTARIES...

WITH BELOW NORMAL STREAM FLOWS AND RESERVOIRS AT OR BELOW
CONSERVATION LEVELS...THE POTENTIAL FOR SPRING FLOODING IS NORMAL
TO SLIGHTLY BELOW NORMAL AT THIS TIME. IT SHOULD BE REMEMBERED
THAT FLOODING IN THE SABINE AND NECHES BASINS RESULTS FROM HEAVY
RAINFALL OVER A SHORT PERIOD OF TIME AND THESE OCCURRENCES CAN NOT
BE PREDICTED WELL IN ADVANCE.

...CALCASIEU AND MERMENTAU RIVERS AND TRIBUTARIES...

DURING THE PAST TWO MONTHS...HEAVY RAINFALL PRODUCED SIGNIFICANT
FLOODING OVER THE MERMENTAU BASIN AND MORE SEASONAL FLOODING ALONG
THE CALCASIEU BASIN. DRIER CONDITIONS OVER THE LAST WEEK HAVE ALLOWED
LOCATIONS TO RECEDE TO BELOW NORMAL STREAMFLOW CONDITIONS. SOIL
MOISTURE CONTENT IS ABOVE NORMAL OVER THE MERMENTAU BASIN AND NEAR
NORMAL OVER THE CALCASIEU BASIN. NO FLOODING IS OCCURRING AND
FLOODING IS NOT EXPECTED DURING THE NEXT SEVERAL DAYS.

BASED ON EXISTING SOIL MOISTURE...STREAMFLOW...AND NORMAL SPRING
RAINFALL PATTERNS...AN ABOVE AVERAGE FLOOD POTENTIAL IS EXPECTED
ACROSS THE MERMENTAU BASIN AND AN AVERAGE FLOOD POTENTIAL IS
EXPECTED ACROSS THE CALCASIEU BASIN.

...LOWER RED RIVER...

STREAMFLOWS ARE BELOW NORMAL FOR THE RED RIVER BASIN DOWNSTREAM OF FULTON
ARKANSAS. DROUGHT CONDITIONS CONTINUE OVER THE UPPER RED BASIN AND
OVERALL SOIL MOISTURE CONTENT IS BELOW NORMAL. NO FLOODING IS
OCCURRING ARE EXPECTED IN THE LOWER RED RIVER BASIN.

BASED ON EXISTING SOIL MOISTURE...STREAMFLOWS...AND NORMAL SPRING
RAINFALL PATTERNS...A BELOW AVERAGE FLOOD POTENTIAL IS EXPECTED
ACROSS THE LOWER RED RIVER VALLEY.

...ATCHAFALAYA RIVER...

SIGNIFICANT SNOW DEPTH CONTINUES OVER THE UPPER MISSISSIPPI VALLEY
AND ABOVE NORMAL PRECIPITATION HAS OCCURRED OVER THE UPPER
MISSISSIPPI VALLEY...LOWER OHIO VALLEY...AND COASTAL SECTIONS OF
THE LOWER MISSISSIPPI VALLEY. ABOVE NORMAL SOIL MOISTURE
CONDITIONS GENERALLY MATCH THE RECENT PRECIPITATION PATTERNS WITH
PORTIONS OF THE UPPER MISSISSIPPI...RED...AND UPPER/MIDDLE PORTIONS
OF THE MISSOURI VALLEYS EXPERIENCING BELOW NORMAL SOIL MOISTURE
AND DROUGHT CONDITIONS.

DURING THE WINTER...SEASONAL FLOODING HAS OCCURRED OVER THE LOWER
OHIO RIVER WHILE BENEFICIAL PRECIPITATION HAS ABATED LOW WATER
CONDITIONS ON THE MIDDLE MISSISSIPPI RIVER. THE OHIO AND
MISSISSIPPI RIVERS ARE CURRENTLY RISING FROM RAINFALL AND SNOWMELT
BUT NO FLOODING IS OCCURRING OR FORECAST AT THIS TIME.

BASED ON EXISTING SOIL MOISTURE...STREAMFLOW CONDITIONS...AND NORMAL
SPRING RAINFALL PATTERNS...AN AVERAGE FLOOD POTENTIAL IS EXPECTED
ALONG THE ATCHAFALAYA RIVER.

THE MAGNITUDE OF FUTURE CRESTS WILL DEPEND ON THE AMOUNT AND
EXTENT OF ANY UPSTREAM ACCUMULATIONS OF SNOW COVER AND RESULTANT
SNOWMELT...COUPLED WITH THE FREQUENCY...INTENSITY...AND EXTENT OF
SPRING RAINS.

PLEASE DIRECT QUESTIONS AND COMMENTS CONCERNING THIS OUTLOOK TO...

JONATHAN BRAZZELL
SERVICE HYDROLOGIST
OR
MONTRA LOCKWOOD
FORECASTER
AT 337.477.5285 EXT 1

 

Link to comment
Share on other sites

HYDROLOGIC OUTLOOK
NATIONAL WEATHER SERVICE AMARILLO TX
936 AM CST THU MAR 7 2013

...SPRING FLOOD OUTLOOK...
...FLOOD RISK IS BELOW AVERAGE FOR THE TEXAS AND OKLAHOMA
PANHANDLES...

THE POTENTIAL FOR FLOOD CONDITIONS WILL BE BELOW NORMAL FOR THE
OKLAHOMA AND TEXAS PANHANDLES.

SOIL MOISTURE CONDITIONS...
PRECIPITATION ACROSS THE PANHANDLES WAS NEAR NORMAL FROM OCTOBER
THROUGH FEBRUARY. SOIL MOISTURE CONDITIONS ARE RUNNING DEFICITS
ACROSS THE PANHANDLES DUE TO THE PROLONGED DROUGHT.

RIVER AND STREAM CONDITIONS...
RIVERS ACROSS THE PANHANDLES ARE RUNNING BELOW NORMAL LEVELS FOR THIS
TIME OF YEAR. RESERVOIRS ARE WELL BELOW CAPACITY.

DROUGHT AREAS...
THE LATEST U.S. DROUGHT MONITOR SHOWS EXTREME TO EXCEPTIONAL DROUGHT
CONDITIONS ACROSS THE OKLAHOMA PANHANDLE AND MODERATE TO
EXTREME DROUGHT CONDITIONS ACROSS MUCH OF THE TEXAS PANHANDLE.
ABNORMALLY DRY CONDITIONS EXIST ACROSS THE SOUTHEAST TEXAS
PANHANDLE. THE FORECAST CALLS FOR PERSISTENT OR INTENSIFYING DROUGHT
CONDITIONS FOR THE NEXT THREE MONTHS.

LONG TERM OUTLOOK...
THE PRECIPITATION OUTLOOK FOR MARCH...APRIL AND MAY FROM THE
NATIONAL WEATHER SERVICE CLIMATE PREDICTION CENTER SHOWS BELOW NORMAL
RAIN CHANCES FOR THE TEXAS AND OKLAHOMA PANHANDLES.

SPRING FLOOD POTENTIAL...
FLASH FLOODING AND SHORT TERM FLOODING IN THE TEXAS AND OKLAHOMA
PANHANDLES USUALLY OCCUR IN RESPONSE TO SPECIFIC PRECIPITATION
EVENTS...BUT CAN ALSO BE TIED TO SOIL MOISTURE...RESERVOIR
STORAGE...OR OTHER PRECURSOR FACTORS. PRECIPITATION IS EXPECTED TO BE
BELOW NORMAL THIS SPRING. THEREFORE...THE OVERALL SPRING FLOOD
POTENTIAL IS BELOW NORMAL.

INFORMATION USED TO COMPILE THIS FLOOD POTENTIAL OUTLOOK WAS
PROVIDED COURTESY OF THE ARKANSAS RED BASIN RIVER FORECAST CENTER...
CLIMATE PREDICTION CENTER...U.S. ARMY CORPS OF ENGINEERS AND THE
UNITED STATES GEOLOGICAL SURVEY.

FOR MORE SPECIFIC WEB INFORMATION CONCERNING RIVER STAGES AND
FORECASTS FOR THE TEXAS AND OKLAHOMA PANHANDLES...GO TO:

                  WWW.SRH.NOAA.GOV/AMA
                  WWW.SRH.NOAA.GOV/ABRFC

 

Link to comment
Share on other sites

HYDROLOGIC OUTLOOK
NATIONAL WEATHER SERVICE NEW ORLEANS LA
900 AM CST THU MAR 7 2013

...2013 SPRING FLOOD POTENTIAL OUTLOOK FOR SOUTHEAST
LOUISIANA...SOUTHWEST MISSISSIPPI...AND COASTAL MISSISSIPPI...

...THE POTENTIAL FOR FLOODING IN SPRING 2013 WILL GENERALLY BE
ABOVE AVERAGE...

INTRODUCTION...

THIS IS THE SPRING FLOOD OUTLOOK ISSUED BY THE NATIONAL WEATHER
SERVICE FORECAST OFFICE AT NEW ORLEANS/BATON ROUGE, LOUISIANA FOR
SOUTHEAST LOUISIANA, SOUTHWEST MISSISSIPPI, AND COASTAL
MISSISSIPPI. THIS PRODUCT IS INTENDED TO OUTLINE CURRENT RIVER AND
SOIL MOISTURE CONDITIONS AND TO HIGHLIGHT POTENTIAL SITUATIONS
THAT WOULD INDUCE FLOODING OR EXACERBATE DROUGHT.

ANTECEDENT CONDITIONS...

PRECIPITATION - OVER THE PAST TWO MONTHS, THE LOWER MISSISSIPPI
VALLEY HAS EXPERIENCED SEVERAL PERIODS OF HEAVY RAINFALL. TO DATE,
PRECIPITATION IS ABOVE NORMAL OVER SOUTH LOUISIANA AND MISSISSIPPI.

SNOW DEPTH - LITTLE SNOW DEPTH EXISTS OVER MOST OF THE MIDDLE
MISSISSIPPI AND OHIO RIVER BASINS AND AREAS SOUTHWARD. SIGNIFICANT
SNOW DEPTHS ARE CONFINED TO THE HIGHER ELEVATIONS OF THE TENNESSEE
VALLEY, WHERE AMOUNTS RANGED FROM 6 TO 12 INCHES.

SNOW WATER EQUIVALENT (SWE) - SWE VALUES FOLLOW A SIMILAR TREND TO
SNOW DEPTH. MOST AREAS THAT REPORTED SNOW DEPTH HAVE SWE VALUES OF
LESS THAN 1.0 INCH.

SOIL MOISTURE CONTENTS - CONDITIONS ARE REFLECTIVE OF RECENT
PRECIPITATION TRENDS. ABOVE NORMAL CONDITIONS EXIST OVER SOUTHEAST
LOUISIANA AND SOUTH MISSISSIPPI.

FLOODING...
MINOR FLOODING IS OCCURRING ON THE LOWER PEARL RIVER AT BOGALUSA AND
PEARL RIVER IN LOUISIANA. BASED UPON CURRENT TRENDS, FLOODING WILL
CONTINUE INTO MID-MARCH.


EXTENDED TEMPERATURE AND PRECIPITATION OUTLOOK...

THE 8-14 DAY PRECIPITATION OUTLOOK ISSUED BY THE NWS CLIMATE
PREDICTION CENTER INDICATED BELOW NORMAL CHANCES OF PRECIPITATION
FOR THE LOWER MISSISSIPPI RIVER VALLEY. THE TEMPERATURE OUTLOOK OVER
THE AREA INDICATED BELOW NORMAL TEMPERATURES FOR THE PERIOD.

THE 30-DAY PRECIPITATION OUTLOOK INDICATED EQUAL CHANCES OF
PRECIPITATION OVER THE LOWER MISSISSIPPI RIVER VALLEY. THE 30-DAY
TEMPERATURE OUTLOOK INDICATED NEAR NORMAL TEMPERATURES.

THE 90-DAY PRECIPITATION OUTLOOK INDICATED BELOW NORMAL CHANCES OF
PRECIPITATION ALONG THE COASTAL SECTIONS OF THE LOWER MISSISSIPPI
VALLEY. FOR THE PERIOD, TEMPERATURES ARE EXPECTED TO BE ABOVE NORMAL
FOR THE ENTIRE LOWER MISSISSIPPI RIVER VALLEY.


MISSISSIPPI RIVER AND ATCHAFALAYA RIVER BASINS...

ABOVE NORMAL PRECIPITATION HAS OCCURRED OVER THE UPPER MISSISSIPPI
VALLEY, LOWER OHIO VALLEY, AND COASTAL SECTIONS OF THE LOWER
MISSISSIPPI RIVER VALLEY. ABOVE NORMAL SOIL MOISTURE CONDITIONS
GENERALLY MATCH THE RECENT RAINFALL/SNOWFALL PATTERNS. NO DROUGHT
CONDITIONS EXIST OVER LOUISIANA OR MISSISSIPPI.

THE OHIO AND MISSISSIPPI RIVERS ARE CURRENTLY RISING FROM RAINFALL
AND SNOWMELT BUT NO FLOODING IS OCCURRING OR FORECAST AT THIS TIME.

SEE THE CHART BELOW FOR SPECIFIC LOCATIONS SHOWING PERCENT OF NORMAL
STREAMFLOWS:

                                             3/6
MISSISSIPPI RIVER           VICKSBURG MS     76%
MISSISSIPPI RIVER             NATCHEZ MS     74%
MISSISSIPPI RIVER   RED RIVER LANDING LA     72%
MISSISSIPPI RIVER         BATON ROUGE LA     72%
MISSISSIPPI RIVER         NEW ORLEANS LA     73%
ATCHAFALAYA RIVER          SIMMESPORT LA     77%


PEARL RIVER BASIN IN SOUTHEAST LOUISIANA AND COASTAL MISSISSIPPI...

PERIODS OF HEAVY RAINFALL CAUSED SEVERAL FLOOD EVENTS ACROSS THE
PEARL RIVER BASIN. THE LOWER PEARL RIVER CONTINUES TO RECEDE BUT
WILL REMAIN ABOVE FLOOD STAGE OVER THE NEXT SEVERAL DAYS. OVERALL
SOIL MOISTURE CONTENT IS WELL ABOVE NORMAL. OBSERVED DAILY
STREAMFLOWS AS A PERCENT OF MEAN ARE GIVEN BELOW.

                                              3/6
PEARL RIVER                MONTICELLO MS      88%
PEARL RIVER                  BOGALUSA LA     214%


AMITE/COMITE/NORTHSHORE DRAINAGE BASINS...

RAINFALL IN JANUARY AND FEBRUARY PRODUCED PERIODS OF FLOODING ACROSS
THE RIVER BASINS IN SOUTHEAST LOUISIANA. DRY CONDITIONS OVER THE
LAST COUPLE OF WEEKS ALLOWED STREAMFLOWS TO RECEDE BELOW SEASONAL
LEVELS. SOIL MOISTURE CONTENT IS ABOVE NORMAL. NO FLOODING IS
OCCURRING AND FLOODING IS NOT EXPECTED DURING THE NEXT SEVERAL DAYS.
OBSERVED DAILY STREAMFLOWS AS A PERCENT OF MEAN ARE GIVEN BELOW.

                                              3/6
AMITE RIVER                DARLINGTON LA      20%
AMITE RIVER            DENHAM SPRINGS LA      25%
COMITE RIVER             OLIVE BRANCH LA      21%
TCHEFUNCTE RIVER               FOLSOM LA      35%
TICKFAW RIVER                  HOLDEN LA      29%
TANGIPAHOA RIVER               ROBERT LA      44%


PASCAGOULA BASIN IN SOUTH MISSISSIPPI.....

HEAVY RAINFALL DURING THE PAST TWO MONTHS HAS CAUSED EXTENSIVE
FLOODING OVER THE PASCAGOULA BASIN. DRY CONDITIONS OVER THE LAST
COUPLE OF WEEKS HAS ALLOWED STREAMFLOWS TO RECEDE TO NEAR SEASONAL
LEVELS. OVERALL SOIL MOISTURE CONTENT IS WELL ABOVE NORMAL. NO
FLOODING IS OCCURRING AND FLOODING IS NOT EXPECTED DURING THE NEXT
SEVERAL DAYS. OBSERVED DAILY STREAMFLOWS AS A PERCENT OF MEAN ARE
GIVEN BELOW.

                                              3/6
PASCAGOULA RIVER              MERRILL MS      78%


2013 SPRING FLOOD OUTLOOK...
BASED ON EXISTING SOIL MOISTURE...STREAMFLOW CONDITIONS...AND
NORMAL SPRING RAINFALL PATTERNS...THE POTENTIAL FOR FLOODING
ACROSS THE REGION IS AVERAGE TO ABOVE AVERAGE.

AN AVERAGE FLOOD POTENTIAL IS EXPECTED ALONG THE LOWER MISSISSIPPI
AND ATCHAFALAYA RIVERS. THE MAGNITUDE OF FUTURE CRESTS WILL DEPEND
ON THE AMOUNT AND EXTENT OF ANY UPSTREAM ACCUMULATIONS OF SNOW COVER
AND RESULTANT SNOWMELT, ALONG WITH THE FREQUENCY, INTENSITY, AND
EXTENT OF SPRING RAINS.

AN ABOVE AVERAGE FLOOD POTENTIAL IS EXPECTED ON THE LOWER PEARL
RIVER DOWNSTREAM OF JACKSON, MS TO THE GULF COAST.

AN ABOVE AVERAGE FLOOD POTENTIAL IS EXPECTED ACROSS THE AMITE,
COMITE, AND OTHER NORTHSHORE RIVER BASINS.

AN ABOVE AVERAGE FLOOD POTENTIAL IS EXPECTED ACROSS THE PASCAGOULA
RIVER BASIN.

STREAMFLOW DATA PROVIDED BY THE U.S. GEOLOGICAL SURVEY AND THE U.S.
ARMY CORPS OF ENGINEERS.

THIS WILL BE THE FINAL SPRING FLOOD OUTLOOK FOR 2013 ISSUED FROM WFO
NEW ORLEANS/BATON ROUGE UNLESS CONDITIONS WARRANT.


PLEASE DIRECT COMMENTS OR QUESTIONS TO:
PATRICIA BROWN
SENIOR SERVICE HYDROLOGIST
WFO NEW ORLEANS/BATON ROUGE, LA
(985) 645-0565 EXT. 228

 

Link to comment
Share on other sites

Good news/bad news- pretty high model agreement on a weakening narrow forced line mid morning for Houston, with about a quarter inch plus/minus a tenth or so, and Austin looks a bit South, strictly based on precip forecasts, of best action.

 

 

Good news, sounding before squall line arrives suggests embedded elevated rotating storms and a chance, at least, for some hail.  Squall lines rarely deliver for anything but wind and brief embedded and generally weak tornadoes, so way less than glass quarter full on solid hydrmeteors in Austin tonight.  And depth of stable layer reduces confidence on severe wind.

 

 

ETA:  That sounding is about 10F too cool at surface for what would be a decent tornado sounding...

post-138-0-89436300-1362844449_thumb.gif

Link to comment
Share on other sites

Away from internet for a while.

 

Cell in (I think) Jack County, severe warned.  I think it is surface based, and from a distance on FWD doppler, may have some rotation.  Severe warned.  MWL may have a bit too much of a T/Td difference for tornadoes.  Temps not that warm, Td's may be a shade too low...

 

I don't know a closer airport code off the top of my head.

Link to comment
Share on other sites

FWD mentioned that this line might stall out west of the metroplex and fizzle.  Looks like that might not happen.

 

THE DIFFICULTY IN THE CONVECTIVE FORECAST THROUGH THIS EVENING IS

THE LACK OF SYNCHRONIZATION OF THIS LINE OF CONVECTION WITH THE

BEST UPPER LEVEL FORCING WHICH DOES NOT ARRIVE UNTIL MID TO LATE

EVENING. HI-RES AND SHORT TERM MODEL GUIDANCE SEEM TO INDICATE

THAT THE CONVECTION ALONG THE FRONT WILL BE CONFINED TO THE NW

ZONES THROUGH 7 OR 8PM...AND MAY ACTUALLY STRUGGLE TO TAKE HOLD OR

EVEN DISSIPATE AS IT APPROACHES THE METROPLEX.

 

ETA: New SPC Dis

 

mcd0262.gif

 

MESOSCALE DISCUSSION 0262   NWS STORM PREDICTION CENTER NORMAN OK   0541 PM CST SAT MAR 09 2013      AREAS AFFECTED...CNTRL/N CNTRL TX INTO ERN OK      CONCERNING...SEVERE THUNDERSTORM WATCH 49...      VALID 092341Z - 100115Z      THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 49   CONTINUES.      SUMMARY...STORMS WITH RISK FOR SEVERE HAIL WILL CONTINUE INTO EARLY   EVENING...MAINLY JUST TO THE WEST OF THE I-35 CORRIDOR OF NORTHERN   AND CENTRAL TEXAS.  ACTIVITY WILL SLOWLY ADVANCE EASTWARD INTO THE   DALLAS/FORT WORTH METROPLEX THROUGH THE 00-02Z TIME FRAME...PERHAPS   ACCOMPANIED BY AN INCREASING RISK FOR STRONG WIND GUSTS...IN   ADDITION TO LARGE HAIL.      DISCUSSION...ONGOING NARROW SQUALL LINE IS ROUGHLY ALIGNED WITH THE   LEADING EDGE OF 700 MB COOLING...EXTENDING WELL AHEAD OF THE SURFACE   DRYLINE...EAST OF THE I-35 CORRIDOR OF OKLAHOMA...SOUTHWARD THROUGH   NORTH CENTRAL TEXAS...INTO ITS INTERSECTION WITH THE DRY LINE ACROSS   THE EDWARDS PLATEAU REGION.  NORTH OF THE RED RIVER...THE BOUNDARY   LAYER HAS REMAINED COOLER AND MORE STABLE...WHICH PROBABLY WILL   CONTINUE TO MINIMIZE THE SEVERE WEATHER THREAT.  THE LATEST RAPID   REFRESH SUGGESTS THAT BOUNDARY LAYER CONVERGENCE REMAINS MAXIMIZED   IN A CORRIDOR JUST AHEAD OF THE SQUALL LINE...NEAR THE DALLAS/FORTH   METROPLEX SOUTHWARD TO THE BOUNDARY INTERSECTION...NORTH OF   JUNCTION.  THIS COINCIDES WITH A NARROW AXIS OF MODERATE MIXED LAYER   CAPE /1000 TO 1500 J PER KG/...IN THE PRESENCE OF STRONG DEEP LAYER   SHEAR BENEATH 50-70 KT SOUTHWESTERLY 500 MB FLOW...WHICH WILL REMAIN   SUPPORTIVE OF SUPERCELL STRUCTURES WITHIN THE EVOLVING LINE.    EVENTUALLY...CONSOLIDATING COLD POOLS COULD CONTRIBUTE TO AN   INCREASING THREAT FOR POTENTIALLY DAMAGING WIND GUSTS.  BUT THE LACK   OF A MORE PRONOUNCED WESTERLY COMPONENT TO THE MID/UPPER FLOW   SUGGESTS EASTWARD PROGRESSION OF THE LINE WILL BE SLOW...AT LEAST   INTO THE 01-03Z TIME FRAME.      ..KERR.. 03/09/2013
Link to comment
Share on other sites

Morning e-mail from Jeff:

 

Stagnant weather pattern in place over the region at least into early next week…maybe longer.

 

High pressure is on control of the local weather and this will result in little day to day variation of the mostly clear skies, cool mornings and mild afternoons with low humidity. Current building surface high will be the final in a series from the north and will push eastward late today allowing winds to veer from the N to E by evening. One last cool morning on Thursday with lows in the 40’s before onshore flow kicks in. Initially the incoming Gulf air mass will be very dry with sprawling high pressure over the SE US sending dry air deep into the Gulf, so not much of a big jump in humidity on Friday. As the large surface high over the eastern US pushes eastward and pressures lower in the plains local winds will turn more SE and S pumping increasingly high moisture and humidity levels into the region over the weekend. Lows will bottom out in the 50’s/60’s over the weekend with highs in the upper 70’s to near 80 as dewpoints climb into the 50’s and then lower 60’s making it feel muggy compared to the recent stretch of dry weather. There will be no chance of rainfall through the entire period as storm system pass well north of our region.

 

 

Link to comment
Share on other sites

I was "lucky" enough to find the biggest hail during yesterday's event. I ended up with hail up to baseball size just north of Decatur. One stone was about half an inch from making me spend money on a new windshield. Definitely a fun chase for me!

Where were you at Dave (when you chased the other night)? The Junction cell had a nice wall cloud. Pics and radar images are in the western thread.

Link to comment
Share on other sites

The overnight guidance continues to advertise a sharp cold front will drop S into the Plains on Thursday bringing much colder temps and perhaps a chance of showers and storms, if capping can be broken.

 

We are heading toward a rather unusual pattern where the Artic Oscillation will drop to near record 6 standard deviations below normal along with a continued blocking West Based North Atlantic Oscillation extending E into Canada as well as a Pacific Ridge extending from Hawaii to Alaska. A strong storm system current NE of Hawaii will translate NE toward the Pacific NW with abundant tropical moisture and drop SE into the Southern/Central Rockies on Thursday. Lee side cyclogenesis will begin in earnest late Thursday as a dry line develops across W Texas. Moisture will begin to race inland from the Gulf Tuesday into Wednesday as pressure fall to our W and an onshore flow becomes established. An unseasonably strong push of much colder air that has been building across Canada will drop well S as a strong surface low develops over the Southern Plains. The best chance of rain would likely come in the form of a squall line that forms across West Texas on Thursday afternoon/evening and marches E into Friday. There still remains a lot of uncertainty about the rain chances due to capping and the persistent drought across our area. An Air Force C-130 Reconnaissance aircraft will sample the Gulf of Alaska area later this afternoon and hopefully that data will provide some clarity for the computer models. The most likely solution will be a quick shot of rainfall for Texas and much better chances of significant rains for Louisiana and points E. We’ll need to closely monitor the trends this week as there is a chance of freezing temps fairly far S into our Region with the first couple of set of Coastal Counties escaping any chance of  those chilly temps. The Spring gardeners further inland will want to follow the forecast a bit more closely as tender plants may need to be protected from the late season cold snap next weekend into early the following week.

 

DAY 4-8 CONVECTIVE OUTLOOK 
   NWS STORM PREDICTION CENTER NORMAN OK
   0356 AM CDT SUN MAR 17 2013
  
   VALID 201200Z - 251200Z
  
   ...DISCUSSION...
   WITH MEDIUM RANGE GUIDANCE IN GENERAL AGREEMENT...BROAD
   CYCLONIC/PROGRESSIVE UPPER FLOW IS EXPECTED TO PREVAIL OVER MUCH OF
   THE CONUS THROUGH MID/LATE WEEK. INITIALLY...LITTLE IF ANY SEVERE
   THREAT IS EXPECTED ON DAY 4/WEDNESDAY.
  
   BY DAY 5/THURSDAY...AT LEAST SOME SEVERE RISK MAY EXIST ACROSS THE
   SOUTHERN PLAINS POTENTIALLY INCLUDING AREAS SUCH AS
   WEST-CENTRAL/NORTH-CENTRAL TX AND PERHAPS INTO OK. AHEAD OF A
   POSSIBLE SHORTWAVE TROUGH/JET STREAK CROSSING THE
   ROCKIES...LOW-LEVEL MOISTURE /MAINLY LOWER 60S F SURFACE DEWPOINTS/
   IS EXPECTED TO RETURN NORTHWARD ACROSS TX/PERHAPS SOUTHERN OK TO THE
   EAST OF A DRY LINE AND SOUTH OF A LATE PERIOD SOUTHWARD-ACCELERATING
   COLD FRONT. WHILE SOME SEVERE TSTMS MAY BE POSSIBLE THURSDAY
   AFTERNOON/NIGHT...UNCERTAINTY EXISTS REGARDING THE DEGREE OF WARM
   SECTOR CAPPING AND THE OVERALL EXTENT/LIKELIHOOD OF ANY SEVERE RISK.
  
   BY DAY 6/FRIDAY...AT LEAST SOME SEVERE POTENTIAL COULD SPREAD
   SOUTHEASTWARD IN ASSOCIATION WITH THE COLD FRONT...INCLUDING A BROAD
   CORRIDOR FROM EAST/SOUTHEAST TX TO THE LOWER MS VALLEY/CENTRAL GULF
   COAST REGION. LIMITED SPECIFIC PREDICTABILITY EXISTS AT THIS
   JUNCTURE AND A 30 PERCENT EQUIVALENT SEVERE RISK AREA IS NOT
   CURRENTLY EXPECTED.

  
   ..GUYER.. 03/17/2013

 

sat_wv_hem_loop-12.gif

Link to comment
Share on other sites

I agree with you Srain. I think this event will be a lot like last weeks event...with the potential to be a little higher on the tornado potential...possibilly significantly higher depending. Below are some images from todays 12Z run...for Thursday and Friday. A few things stood out to me...to keep an eye on in later model runs. First...the temporary stalling of the front (even slight retrograde over the Concho Valley - west central part of the counties) between 00Z and 06Z...due to the wave to the south. This happened weeks event. I like the instability gradient coupled with the shear...with good directional shear ahead of the front for Thursday. On Friday...the model shows the best shear post-frontal...but this could change. With it still being a few days out...we'll see.

post-767-0-17582900-1363545342_thumb.jpg

post-767-0-83992500-1363545369_thumb.jpg

post-767-0-09077100-1363545641_thumb.jpg

post-767-0-93966600-1363545697_thumb.jpg

post-767-0-46982500-1363545740_thumb.jpg

post-767-0-01819700-1363545766_thumb.jpg

post-767-0-85562200-1363545816_thumb.jpg

Link to comment
Share on other sites

I'm mildly interested in the supercell potential Thursday from C TX up to SW OK. Directional shear from the surface to H5 will be on the order of 120 degrees, which could help to compensate for the numerous weaknesses of the setup. However, capping will be a concern, particularly unless solar heating can warm sfc temps nicely through the afternoon.

Link to comment
Share on other sites

I'm mildly interested in the supercell potential Thursday from C TX up to SW OK. Directional shear from the surface to H5 will be on the order of 120 degrees, which could help to compensate for the numerous weaknesses of the setup. However, capping will be a concern, particularly unless solar heating can warm sfc temps nicely through the afternoon.

The solar heating will be more of an issue north of Interstate 20 I think...with capping the main issue south of there. The front should weaken the EML though...as it has in several events this year...at least in central Texas...but that's if the model forecasts don't change. Using today's 12Z run...to me...supercells would be likely east of a Ozona...to Abilene...to Wichita Falls line.

Link to comment
Share on other sites

Some chance of severe here as well days 4-5, but cap is usually very strong, and precip has been  almost non existent so far this year, so I'm not very hopeful. In the meantime, 102F just a few moments ago, consolidating the area as the hotspot of the W hemisphere this time of the year.

 

METAR MMMY 172142Z 32010KT 12SM SCT040 39/M11 A2961 RMK 8/500

Link to comment
Share on other sites

Some chance of severe here as well days 4-5, but cap is usually very strong, and precip has been  almost non existent so far this year, so I'm not very hopeful. In the meantime, 102F just a few moments ago, consolidating the area as the hotspot of the W hemisphere this time of the year.

 

METAR MMMY 172142Z 32010KT 12SM SCT040 39/M11 A2961 RMK 8/500

You may have hope for the weekend. The models show a secondary piece of vorticity diving into Baja California then moving east right at you. As a result...a weak sfc low formed and the models (this was the GFS model...but the euro showed the same thing) showed a decent precip event there. Still a ways out...so we'll see.

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

Guest
This topic is now closed to further replies.
  • Recently Browsing   0 members

    • No registered users viewing this page.

×
×
  • Create New...