EPAC : TROPICAL DEPRESSION OLAF (18E)

[cycloneye]

WTPZ43 KNHC 022032
TCDEP3
TROPICAL STORM OLAF DISCUSSION NUMBER 6
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP182009
200 PM PDT FRI OCT 02 2009

SATELLITE IMAGERY SHOWS THAT CLOUD TOPS HAVE WARMED IN ASSOCIATION
WITH OLAF OVER THE PAST FEW HOURS...AS THE SSTS OF LESS THAN 25C
ARE TAKING A TOLL ON THE CYCLONE. ALSO...THE LOW-LEVEL CIRCULATION
CENTER APPEARS TO BE DECOUPLING FROM THE MID-LEVEL CIRCULATION...
LIKELY DUE TO THE 15-20 KNOTS OF SOUTHWESTERLY SHEAR SEEN IN
ANALYSES FROM UW-CIMSS. GIVEN THE DEGRADED SATELLITE APPEARANCE...
THE INITIAL INTENSITY IS LOWERED TO 35 KT. THIS IS IN AGREEMENT WITH
DVORAK CI-NUMBERS FROM TAFB AND SAB AND A 32-KT WIND OBSERVED BY
SHIP 3FXY2 ABOUT 150 MILES NORTH OF THE CENTER AT 1800 UTC. FURTHER
WEAKENING IS EXPECTED DUE TO COOL WATERS AND THE SHEAR INCREASING TO
MORE THAN 30 KT IN 24 HOURS...AS INDICATED BY THE SHIPS MODEL. THE
OFFICIAL FORECAST IS IN CLOSE AGREEMENT WITH THE ICON INTENSITY
CONSENSUS...AND SHOWS OLAF BECOMING A REMNANT LOW BY 36 HOURS AND
DISSIPATING BY 48 HOURS...ALTHOUGH THIS COULD OCCUR SOONER.

THE INITIAL MOTION ESTIMATE IS 010/08...A LITTLE TO THE RIGHT OF
PREVIOUS ESTIMATES AND THE PREVIOUS FORECAST. THE MODEL GUIDANCE IS
IN GOOD AGREEMENT ON THE OVERALL TRACK SCENARIO...WITH OLAF TURNING
TOWARD THE NORTHEAST AND EAST-NORTHEAST AHEAD OF A MID-LEVEL TROUGH
APPROACHING THE CALIFORNIA COAST IN THE NEXT DAY OR SO. THE TRACK
FORECAST IS ADJUSTED TOWARD THE NEW MODEL CONSENSUS...BUT IS SLOWER
THAN MOST OF THE GUIDANCE BASED ON THE ASSUMPTION THAT THE
LOW-LEVEL CIRCULATION WILL CONTINUE TO DECOUPLE. WHAT IS LEFT OF
THE CIRCULATION SHOULD DISSIPATE OVER THE RUGGED TERRAIN OF THE
BAJA PENINSULA BY 48 HOURS.

RAINFALL ASSOCIATED WITH OLAF WILL SPREAD INTO CENTRAL PORTIONS OF
THE BAJA PENINSULA TONIGHT AND SATURDAY.

FORECAST POSITIONS AND MAX WINDS

INITIAL 02/2100Z 23.8N 117.2W 35 KT
12HR VT 03/0600Z 24.8N 116.7W 30 KT
24HR VT 03/1800Z 26.0N 115.4W 25 KT
36HR VT 04/0600Z 27.0N 113.4W 20 KT...REMNANT LOW
48HR VT 04/1800Z...DISSIPATED

$$
FORECASTER BRENNAN

[somethingfunny]

For those in TX and points East...

OMG the LBAR is headed right for my house!!!!!

On the bright side at least the forecast points are properly spaced. No flood-causing stall in the forecast for this one. We should hopefully get lots of rainfall but not too much out of Olaf.

[cycloneye]

TCDEP3
TROPICAL STORM OLAF DISCUSSION NUMBER 7
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP182009
800 PM PDT FRI OCT 02 2009

THE LOW-LEVEL CENTER HAS CONTINUED TO BECOME SEPARATED FROM THE
CONVECTION AS INDICATED BY MICROWAVE DATA. MOST OF THE THUDERSTORM
ACTIVITY IS CONFINED TO A FEW CYCLONICALLY-CURVED CONVECTIVE BANDS
TO THE NORTH AND EAST OF THE CENTER...AND DESPITE THE SHEAR...THE
OUTFLOW IS NOT UNIDIRECTIONAL YET. DVORAK T-NUMBERS STILL SUPPORT
AN INITIAL INTENSITY OF 35 KNOTS. GIVEN THE DEGRADATION OF THE
CLOUD PATTERN AND THE FACT THAT OLAF IS MOVING OVER COOLER WATERS
AND EMBEDDED IN INCREASING SHEAR...WEAKENING IS FORECAST. OLAF IS
EXPECTED TO BE NEAR THE WEST COAST OF BAJA CALIFORNIA AS A
WEAKENING DEPRESSION OR EVEN AS A REMNANT LOW ON SATURDAY.

OLAF HAS ALREADY RECURVED WHILE EMBEDDED IN THE SOUTHWESTERLY
MID-LATITUDE FLOW AND IS NOW MOVING TOWARD THE NORTHEAST OR 040
DEGREES AT 8 KNOTS. THIS GENERAL MOTION SHOULD CONTINUE UNTIL
DISSIPATION IN A DAY OR SO. THIS IS CONSISTENT WITH MOST OF THE
TRACK GUIDANCE WHICH UNANIMOUSLY MOVE A WEAKENING OLAF
NORTHEASTWARD.

RAINFALL ASSOCIATED WITH OLAF WILL CONTINUE TO SPREAD INTO CENTRAL
PORTIONS OF THE BAJA PENINSULA TONIGHT AND SATURDAY.


FORECAST POSITIONS AND MAX WINDS

INITIAL 03/0300Z 24.5N 116.5W 35 KT
12HR VT 03/1200Z 25.5N 115.5W 30 KT
24HR VT 04/0000Z 26.5N 113.5W 25 KT
36HR VT 04/1200Z 27.5N 111.0W 20 KT...REMNANT LOW
48HR VT 05/0000Z...DISSIPATED

$$
FORECASTER AVILA

[supercane]

Olaf bringing rain over SW. From the Tucson AFD:

000
FXUS65 KTWC 030315
AFDTWC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
815 PM MST FRI OCT 2 2009

.SYNOPSIS...AN INCREASE IN MOISTURE ASSOCIATED WITH THE REMNANTS OF
TROPICAL STORM OLAF WILL BRING MOSTLY CLOUDY SKIES TO SOUTHEAST
ARIZONA THIS WEEKEND...ALONG WITH SCATTERED RAIN SHOWERS ESPECIALLY
SOUTH AND EAST OF TUSCON. EXPECT AFTERNOON TEMPERATURES TO FALL
BELOW NORMAL THROUGH THE WEEKEND AND MOST OF NEXT WEEK.

&&

.DISCUSSION...STRONG MOISTURE ADVECTION UNDERWAY...AND EXPECTED TO
CONTINUE INTO THE WEEKEND. IR IMAGERY SHOWS WIDESPEAD HIGH AND MID
CLOUDS OVERSPREADING SOUTHERN ARIZONA THIS EVENING. BLENDED PRECIP
WATER PRODUCTS CLEARLY SHOW MOISTURE HEADING NORTH THIS EVENING
ACROSS SONORA INTO ARIZONA...WITH THE BEGINNING OF THE MID LEVEL
MOISTENING NOTED ON THE 00Z KTWC SOUNDING. TROPICAL STORM OLAF
CONTINUES TO HOLD HIS OWN...WITH VERY COLD THUNDERSTORM CLOUD TOPS
NEAR -84C EAST OF THE CENTER THIS EVENING. AS OLAF WEAKENS
OVERNIGHT...MOISTURE WILL CONTINUE TO INCREASE ACROSS SOUTHEAST
ARIZONA. IN COORDINATION WITH WFO PHOENIX...UPPED THE SKY GRIDS TO
MOSTLY CLOUDY TONIGHT AND MENTIONED SPRINKLES IN THE TEXT PRODUCTS.
HAVE ALREADY RECEIVED REPORTS OF LIGHT RAIN FROM IMPERIAL AND YUMA
TO OUR WEST...WITH RADAR COMPOSITE INDICATING WIDESPREAD VIRGA WITH
OCCASIONAL SPRINKLES FROM PHOENIX...TO GILA BEND...TO YUMA...WITH
MORE HEADING TOWARD WESTERN PIMA COUNTY FROM THE BAJA AND NORTHWEST
SONORA. CERTAINLY...THE VAST MAJORITY OF THIS IS EVAPORATING LONG
BEFORE REACHING THE SURFACE. BUT STILL...00Z NAM CONTINUES TO
FORECAST A VERY RAPID MOISTENING OVERNIGHT. GIVEN THE REPORTS OUT
WEST...SPRINKLES/LIGHT RAIN WILL BECOME INCREASING LIKELY OVERNIGHT
AS CLOUDS THICKEN AND LOWER. NAM IS FORECASTING RAIN TO BE IN
PROGRESS FROM NEAR NOGALES TO DOUGLAS AT SUNRISE TOMORROW. AM
SOMEWHAT CONCERNED THAT PRECIP WILL END UP SOMEWHAT FURTHER NORTH
THAN THIS SOLUTION...GIVEN THE CURRENT RADAR TRENDS. THE BEST
CHANCES FOR SIGNIFICANT/MEASURABLE RAINFALL STILL APPEAR TO BE
ACROSS SANTA CRUZ AND COCHISE COUNTIES BY SATURDAY MORNING. IN SHARP
CONTRAST TO OUR BONE DRY AIR TODAY...SURFACE DEWPOINTS ARE PROGGED
BY NAM TO REACH THE LOW TO MID 50S AS FAR NORTH AS TUCSON TOMORROW
EVENING. BUMPED UP MIN TEMPS ABOUT 4 DEGREES ACROSS THE BOARD
TONIGHT AS CLOUDS AND MOISTURE PUT THE BRAKES ON RADIATIONAL
COOLING. CLOUDS AND A DROP IN 850 TEMPS OF ABOUT 5C WILL RESULT IN
NOTICEABLE AND WELCOME COOLING TOMORROW. INHERITED FORECAST HAS
HIGHS IN THE MID 80S AT KTUS AND UPPER 70S AT KDUG...AND FEEL MANY
US WILL STRUGGLE TO REACH EVEN THESE NUMBERS. 00Z NAM MOS IS
FORECASTING A HIGH OF ONLY 67 AT DOUGLAS TOMORROW AND 72 AT
NOGALES...ENTIRELY POSSIBLE IF GIVEN A CLOUDY RAINY DAY.
AGAIN...FEELING IS THE MOST WIDESPREAD RAIN/CLOUDS WILL STAY FOCUSED
ACROSS SANTA CRUZ AND COCHISE COUNTIES. FREQUENT UPDATES ARE TO BE
EXPECTED THROUGH TOMORROW AS WE NAIL DOWN THE NORTHWEST EDGE OF THE
ANTICIPATED RAIN SHIELD. VERY TIGHT POP/QPF GRADIENTS EXPECTED.

[cycloneye]

43 KNHC 030836
TCDEP3
TROPICAL DEPRESSION OLAF DISCUSSION NUMBER 8
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP182009
200 AM PDT SAT OCT 03 2009

A SERIES OF MICROWAVE PASSES INDICATE THAT THE LOW-LEVEL CENTER OF
OLAF IS LOCATED WELL TO THE WEST OF THE MID-LEVEL CIRCULATION THAT
IS APPARENT IN SHORTWAVE INFRARED IMAGES. THIS DECOUPLED STRUCTURE
IS DUE TO ABOUT 25 KT OF SOUTHWESTERLY VERTICAL WIND SHEAR...
ACCORDING TO ANALYSES FROM CIMSS AT THE UNIVERSITY OF WISCONSIN. A
0532 UTC HIGH RESOLUTION ASCAT PASS SHOWED MAXIMUM WINDS IN THE
25-30 KT RANGE. BASED ON THIS PASS AND SATELLITE INTENSITY
ESTIMATES...OLAF IS BEING DOWNGRADED TO A TROPICAL DEPRESSION WITH
THE INITIAL INTENSITY SET AT 30 KT. DESPITE SLIGHTLY WARMER SEA
SURFACE TEMPERATURES ALONG THE FORECAST TRACK...OLAF IS EXPECTED TO
WEAKEN DUE TO EVEN STRONGER SHEAR FORECAST BY THE SHIPS MODEL.
OLAF IS FORECAST TO BECOME A REMNANT LOW BY 36 HOURS...IN AGREEMENT
WITH MUCH OF THE MODEL GUIDANCE.

BASED ON MICROWAVE DATA...THE INITIAL MOTION HAS SLOWED AND IS
SLIGHTLY LEFT OF THE PREVIOUS ESTIMATE AT 010/3. OLAF WILL SHORTLY
TURN NORTHEASTWARD...IF IT HAS NOT ALREADY...AND ACCELERATE AS IT
MOVES INTO DEEP-LAYER SOUTHWESTERLY FLOW TAKING OLAF OR ITS
REMNANTS ACROSS THE CENTRAL BAJA PENINSULA TONIGHT. THIS TRACK
FORECAST IS A LITTLE SLOWER THAN THE PREVIOUS ONE TO ACCOUNT FOR
THE INITIAL MOTION.

RAINFALL ASSOCIATED WITH OLAF WILL CONTINUE TO SPREAD INTO CENTRAL
PORTIONS OF THE BAJA PENINSULA AND NORTHWESTERN MEXICO TODAY AND
TONIGHT.

FORECAST POSITIONS AND MAX WINDS

INITIAL 03/0900Z 24.1N 117.2W 30 KT
12HR VT 03/1800Z 25.3N 116.1W 30 KT
24HR VT 04/0600Z 26.5N 114.4W 25 KT
36HR VT 04/1800Z 27.5N 111.6W 20 KT...REMNANT LOW
48HR VT 05/0600Z...DISSIPATED

$$
FORECASTER CANGIALOSI/BEVEN

[HURAKAN]

Heavy precipitation over BC

[srainhoutx]

Heavy precipitation over BC

Just posted in the USA Weather Topic. TS Olaf is a bit S of forecast track and concentrated moisture is rather stout. Where Olaf reminant tracks will likely cause higher heavy rainfall totals. Although Olaf is not a strong TC, the moisture along with imbedded short wave activity in the W/SW flow will provide a lot of rain for many folks from TX eastward in the coming days. Folks in the SE will also see more rainfall, so attention will need to be maintained as those areas of MS, AL, and GA have seen impressive flooding issues of late.

[cycloneye]

000
WTPZ43 KNHC 031437
TCDEP3
TROPICAL DEPRESSION OLAF DISCUSSION NUMBER 9
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP182009
800 AM PDT SAT OCT 03 2009

OLAF IS CONTINUING TO SHEAR APART...WITH THE MID- AND UPPER-LEVEL
CIRCULATION BEING ADVECTED NORTHEASTWARD ON THE SOUTHERN FLANK OF A
130-KT UPPER-LEVEL JET CENTERED OVER THE SOUTHWESTERN UNITED
STATES. THE INITIAL INTENSITY IS HELD AT 30 KT BASED ON DVORAK
CI-NUMBERS OF 2.0 FROM TAFB AND SAB...AND A 30-KT OBSERVATION FROM
SHIP 3EUS AT 1000 UTC. THE SHIPS MODEL SHOWS THE SHEAR INCREASING
TO AROUND 40 KT IN 24 HOURS...AND THIS SHOULD RESULT IN AN
INCREASING SEPARATION OF THE LOW-LEVEL CENTER FROM ANY REMAINING
DEEP CONVECTION. THEREFORE...OLAF SHOULD GRADUALLY WEAKEN AND IS
EXPECTED TO BE A REMNANT LOW BY 24 HOURS. THE LOW-LEVEL CIRCULATION
SHOULD DISSIPATE BY 36 HOURS OVER THE RUGGED TERRAIN OF THE BAJA
PENINSULA.

THE FIRST VISIBLE SATELLITE IMAGES SUGGEST THAT THE LOW-LEVEL CENTER
OF OLAF IS MOVING EAST-NORTHEASTWARD...WITH AN INITIAL MOTION
ESTIMATE OF 075/07. THIS PLACES THE CENTER WELL SOUTHEAST OF
PREVIOUS ESTIMATES. AN ACCELERATION TOWARD THE EAST-NORTHEAST IS
EXPECTED TODAY IN THE SOUTHWESTERLY FLOW AHEAD OF A DEEP-LAYER
TROUGH DIGGING SOUTHWARD ALONG THE WEST COAST OF THE UNITED STATES.
THE OFFICIAL FORECAST IS ADJUSTED SIGNIFICANTLY TO THE SOUTHEAST OF
THE PREVIOUS PACKAGE DUE TO THE LOCATION AND INITIAL MOTION. THE
NEW TRACK FORECAST IS IN BEST AGREEMENT WITH THE HWRF AND IS SOUTH
OF THE MODEL CONSENSUS...AS MOST OF THE GUIDANCE APPEARS TO BE
TAKING OLAF TOO FAR NORTHWARD GIVEN THE CURRENT MOTION.

RAINFALL AND GUSTY WINDS ASSOCIATED WITH OLAF WILL CONTINUE TO
SPREAD ACROSS CENTRAL PORTIONS OF THE BAJA PENINSULA AND
NORTHWESTERN MEXICO TODAY AND TONIGHT.

FORECAST POSITIONS AND MAX WINDS

INITIAL 03/1500Z 24.2N 115.2W 30 KT
12HR VT 04/0000Z 24.7N 114.0W 25 KT
24HR VT 04/1200Z 25.6N 112.0W 20 KT...REMNANT LOW
36HR VT 05/0000Z...DISSIPATED

$$
FORECASTER BRENNAN

[cycloneye]

000
WTPZ43 KNHC 032030
TCDEP3
TROPICAL DEPRESSION OLAF DISCUSSION NUMBER 10
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP182009
200 PM PDT SAT OCT 03 2009

THE EXPOSED LOW-LEVEL CENTER OF OLAF IS DISPLACED ABOUT 180 N MI
SOUTHWEST OF THE REMAINING DEEP CONVECTION...WHICH IS NOW MOVING
ACROSS THE GULF OF CALIFORNIA AND INTO THE MEXICAN STATES OF SONORA
AND SINALOA. THE DEPRESSION IS NOW UNCLASSIFIABLE BY THE DVORAK
TECHNIQUE...BUT LA PAZ RECENTLY REPORTED SUSTAINED WINDS OF 28 KT
AND A 1406 UTC QUIKSCAT PASS INDICATED THAT WINDS WERE STILL NEAR
30 KT. THEREFORE...THE INITIAL INTENSITY IS BEING HELD AT 30 KT.
NOW THAT ALL THE DEEP CONVECTION HAS BEEN SHEARED TO THE
NORTHEAST...CONTINUED WEAKENING IS EXPECTED...AND OLAF SHOULD BE A
REMNANT LOW WITHIN THE NEXT 12 HOURS. DISSIPATION IS ANTICIPATED BY
36 HOURS ONCE THE CIRCULATION INTERACTS WITH THE TERRAIN OF BAJA
CALIFORNIA.

THE DECOUPLED LOW-LEVEL CENTER HAS BEEN MOVING FASTER AND FARTHER
SOUTH THAN PREVIOUSLY ESTIMATED AT 095/13...LIKELY DUE TO THE
CLIMATOLOGICAL NORTHERLY FLOW OFF THE WESTERN BAJA COAST. THIS
FLOW SHOULD LESSEN AS THE CENTER GETS CLOSER TO LAND...AND THE
REMNANT CIRCULATION IS EXPECTED TO TURN TOWARD THE EAST-NORTHEAST
AND MOVE INTO THE SOUTHERN BAJA PENINSULA OVER THE NEXT 12 TO 24
HOURS. NEITHER THE DYNAMICAL NOR THE BETA ADVECTION MODELS HAVE
CORRECTLY FORECAST THE RECENT EASTWARD MOTION...AND THE RESULTING
OFFICIAL FORECAST IS WELL SOUTH OF THE MODEL ENVELOPE AND IS CLOSER
TO CLIPER.

RAINFALL AND GUSTY WINDS ASSOCIATED WITH OLAF WILL CONTINUE TO
SPREAD ACROSS PORTIONS OF NORTHWESTERN MEXICO TODAY AND TONIGHT.

FORECAST POSITIONS AND MAX WINDS

INITIAL 03/2100Z 23.8N 113.3W 30 KT
12HR VT 04/0600Z 23.9N 111.4W 25 KT...REMNANT LOW
24HR VT 04/1800Z 24.5N 109.5W 20 KT...REMNANT LOW
36HR VT 05/0600Z...DISSIPATED

$$
FORECASTER BERG

[cycloneye]

Last Advisory

HC 040230
TCDEP3
TROPICAL DEPRESSION OLAF DISCUSSION NUMBER 11
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP182009
800 PM PDT SAT OCT 03 2009

OLAF HAS WEAKENED AND IS NOW A REMNANT LOW. THE SYSTEM CONSISTS OF A
TIGHT SWIRL OF LOW CLOUDS APPROACHING THE WEST COAST OF SOUTHERN
BAJA CALIFORNIA. MOST OF THE CLOUDINESS AND RAIN HAVE MOVED RAPIDLY
TO THE NORTHEAST AWAY FROM THE LOW LEVEL CENTER AND ARE ALREADY
OVER MAINLAND MEXICO. THE LOW IS FORECAST TO FURTHER WEAKEN OVER THE
TERRAIN OF BAJA CALIFORNIA BUT COULD STILL PRODUCE SHOWERS AND
GUSTY WINDS.

THE REMNANT LOW IS MOVING TOWARD THE EAST OR 085 DEGREES AT 10 KNOTS
AND THIS GENERAL MOTION IS EXPECTED TO CONTINUE UNTIL DISSIPATION.
RAINFALL AND GUSTY WINDS ASSOCIATED WITH THE REMNANTS OF OLAF WILL
CONTINUE TO SPREAD ACROSS PORTIONS OF NORTHWESTERN MEXICO TONIGHT.

THIS WILL BE THE LAST ADVISORY ON OLAF. FOR ADDITIONAL INFORMATION
ON THE REMNANT LOW PLEASE SEE HIGH SEAS FORECASTS ISSUED BY THE
NATIONAL WEATHER SERVICE...UNDER AWIPS HEADER NFDHSFEPI AND WMO
HEADER FZPN02 KWBC.


FORECAST POSITIONS AND MAX WINDS

INITIAL 04/0300Z 24.1N 112.3W 25 KT
12HR VT 04/1200Z 24.5N 110.5W 20 KT...REMNANT LOW
24HR VT 05/0000Z 25.5N 109.0W 20 KT...REMNANT LOW
36HR VT 05/1200Z...DISSIPATED

$$
FORECASTER AVILA

[srainhoutx]

Maybe the last advisory, but Olaf may well be remembered as a Heavy rainfall/Flooding event in TX and points eastward.