EPAC: RAYMOND - Tropical Storm

[cycloneye]

TROPICAL STORM RAYMOND DISCUSSION NUMBER 20
NWS NATIONAL HURRICANE CENTER MIAMI FL EP172013
200 PM PDT THU OCT 24 2013

CLUSTERS OF THUNDERSTORMS CONTINUE TO FORM NEAR THE CENTER OF
RAYMOND...BUT APPARENTLY HAVE NOT RESULTED IN ANY INTENSIFICATION
YET WITH A RECENT PARTIAL ASCAT PASS SHOWING MAXIMUM WINDS OF ABOUT
35 KT. THE INITIAL WIND SPEED IS KEPT AT 40 KT AS A COMPROMISE
BETWEEN THE ASCAT AND 45-KT DVORAK ESTIMATES FROM TAFB/SAB SINCE
THE ASCAT DID NOT COVER THE WHOLE CIRCULATION. SATELLITE IMAGES
SHOW THAT THE UPPER-LEVEL FLOW IS BECOMING SOUTHEASTERLY NEAR
RAYMOND...WHICH SHOULD RESULT IN A LOWER-SHEAR PATTERN. MODEL
GUIDANCE IS A LITTLE HIGHER THAN THE LAST CYCLE...WITH THE SHIPS
MODEL JOINING THE GFDL IN FORECASTING RAYMOND TO BECOME A HURRICANE
AGAIN. WHILE I AM NOT QUITE READY TO BELIEVE THOSE MODELS
VERBATIM...I THINK THEY HAVE THE RIGHT TREND GIVEN THE EVOLVING
UPPER-LEVEL WINDS. THE NEW FORECAST IS RAISED ABOVE THE PREVIOUS
ONE...BETWEEN THE INTENSITY CONSENSUS AND THE LATEST SHIPS MODEL.
WEAKENING WILL PROBABLY COMMENCE BY DAY 5 DUE TO INCREASING
SOUTHERLY SHEAR AND COOLING SSTS.

THE ASCAT PASS HELPED TO SOLIDIFY AN INITIAL MOTION ESTIMATE OF
270/9. THERE HAS BEEN NO SIGNIFICANT CHANGE TO THE MODEL GUIDANCE
WITH A WEST-SOUTHWESTWARD MOTION LIKELY FOR THE NEXT FEW DAYS DUE
TO A RIDGE SOUTH OF BAJA CALIFORNIA. AFTER THAT TIME...THE ECMWF
CONTINUES TO BE ON ITS OWN IN FORECASTING A RECURVATURE OF RAYMOND
EAST OF 119W AHEAD OF AN ADVANCING MID-LATITUDE TROUGH...WITH THE
TROPICAL CYCLONE ENDING UP MUCH FARTHER NORTHEAST THAN ANY OTHER
MODEL BY DAY 5. THE LATEST MULTI-MODEL CONSENSUS HAS SHIFTED
NORTHEASTWARD...BUT IS STILL WEST OF THE PREVIOUS NHC TRACK
FORECAST. FOR NOW THE NEW NHC PREDICTION WILL STAY CLOSE TO THE
PREVIOUS ONE...AND IT WILL BE INTERESTING TO SEE IF LATER RUNS OF
THE GLOBAL MODELS SHIFT TOWARD THE ECMWF SOLUTION.


FORECAST POSITIONS AND MAX WINDS

INIT 24/2100Z 14.8N 106.8W 40 KT 45 MPH
12H 25/0600Z 14.6N 108.2W 45 KT 50 MPH
24H 25/1800Z 14.2N 110.4W 45 KT 50 MPH
36H 26/0600Z 13.7N 112.7W 50 KT 60 MPH
48H 26/1800Z 13.4N 114.9W 50 KT 60 MPH
72H 27/1800Z 13.5N 118.7W 55 KT 65 MPH
96H 28/1800Z 15.0N 120.5W 55 KT 65 MPH
120H 29/1800Z 16.5N 120.5W 45 KT 50 MPH

$$
FORECASTER BLAKE

[TropicalAnalystwx13]

It'll be interesting to see how strong Raymond becomes this time. Wind shear won't be overly favorable like it was during the storm's first intensification phase, but we might be able to see this get back up to hurricane intensity before wind shear increases once again and sea surface temperatures fall.

[hurricanes1234]

Best Track gave us wrong information about its strength.

[supercane4867]

Got an ASCAT pass over Raymond a few hours ago. It indicated max winds may be about 30 kts.

Gabrielle was named in the caribbean when ASCAT barely showing anything. There should be little doubt about Raymond being a TS right now

[Yellow Evan]

Impressive burst of cooling cloud tops over the no longer exposed centre. What amazes me is that this system is able to generate convection like this at diurnal minimum.

How? TC's are suppose to do that, that's why they are TC's and not invests

[hurricanes1234]

Impressive burst of cooling cloud tops over the no longer exposed centre. What amazes me is that this system is able to generate convection like this at diurnal minimum.

How? TC's are suppose to do that, that's why they are TC's and not invests

At diurnal minimum. 45 mph storms usually lose at least a little convection at diurnal minimum.

[hurricanes1234]

Convection is seriously on the increase in both coverage and intensity. Would be surprised if this is still 45 mph or less by 8 PM PDT.

[supercane4867]

Much better organized with possible CDO feature forming




CI3.7/59kt from SSD

2013OCT24 230000 3.7 991.3 59.0 3.7 3.8 3.7 NO LIMIT OFF OFF -70.26 -73.90 UNIFRM

[cycloneye]

Up to 50kts.

EP, 17, 2013102500, , BEST, 0, 147N, 1073W, 50, 998, TS

[hurricanes1234]

Just 14 mph to go before this reaches hurricane strength! I have confidence this will reintensify into a nice Category 1 fish.


NOT OFFICIAL, JUST MY AMETEUR OPINION.

[supercane4867]

New guidance trending upward

[CrazyC83]

TXPZ25 KNES 250019
TCSENP

A. 17E (RAYMOND)

B. 25/0000Z

C. 14.6N

D. 107.3W

E. THREE/GOES-W

F. T3.0/3.0/D0.5/06HRS

G. IR/EIR/SWIR

H. REMARKS...CONVECTION WRAPS .6 ON LOG10 SPIRAL YIELDING A DT OF 3.0.
MET = 3.5 AND PT = 3.0. FT IS BASED ON DT.

I. ADDL POSITIONS

NIL


...KIBLER

[CrazyC83]

Wow, GFDL makes it a major hurricane again...

[supercane4867]

Wrapping up

[Yellow Evan]

I doubt this system will become a major again. Only storm to become a MH then TS then MH in basin history was Doreen 73, though Trudy 90 was close.

[cycloneye]

TROPICAL STORM RAYMOND DISCUSSION NUMBER 21
NWS NATIONAL HURRICANE CENTER MIAMI FL EP172013
800 PM PDT THU OCT 24 2013

RAYMOND HAS MADE A COMEBACK TONIGHT. A LARGE CLUSTER OF DEEP
CONVECTION HAS FORMED NEAR THE CENTER...AND THE OVERALL CLOUD
PATTERN HAS BECOME BETTER ORGANIZED. THE INITIAL INTENSITY HAS BEEN
ADJUSTED UPWARD TO 50 KNOTS...BASED ON A BLEND OF SUBJECTIVE
T-NUMBERS FROM TAFB AND SAB...AND OBJECTIVE NUMBERS FROM THE
UNIVERSITY OF WISCONSIN. THE GLOBAL MODELS...PRIMARILY THE GFS AND
THE ECMWF...HAVE DONE A REMARKABLY GOOD JOB IN FORECASTING THE
CHANGE FROM UNFAVORABLE TO FAVORABLE UPPER-LEVEL WINDS. NOW THAT
THIS FAVORABLE PATTERN HAS MATERIALIZED...AS SEEN BY A WESTWARD
EXPANSION OF THE OUTFLOW...THE NHC FORECAST CALLS FOR RAYMOND TO
REACH HURRICANE STRENGTH AGAIN IN A DAY OR SO OVER OPEN WATERS.
THIS IS CONSISTENT WITH THE INTENSITY CONSENSUS AND WITH THE UPWARD
INTENSITY TREND SHOWN BY GUIDANCE TONIGHT. THE HWRF APPEARS TO BE
ALONE IN THIS FORECAST CYCLE...KEEPING RAYMOND ON A GRADUAL STEADY
DECAY OR WITH NO CHANGE IN INTENSITY. BY THE END OF THE FORECAST
PERIOD...WHEN THE SHEAR INCREASES WITH THE ARRIVAL OF A NEW MID- TO
UPPER-LEVEL TROUGH...AND THE INFLUENCE OF COOLER WATERS...WEAKENING
SHOULD THEN BEGIN.

THE SUBTROPICAL RIDGE TO THE NORTH OF RAYMOND HAS CONTINUED TO
EXPAND AND IS FORCING THE CYCLONE TO MOVE TOWARD THE WEST OR 265
DEGREES AT 9 KNOTS. THIS SUBTROPICAL RIDGE IS NOT GOING ANYWHERE
DURING THE NEXT 3 DAYS OR SO...AND THIS STEERING PATTERN WILL KEEP
RAYMOND ON A GENERAL WESTWARD TRACK AWAY FROM MEXICO. BY DAY 4
AND BEYOND...THE SAME APPROACHING TROUGH WHICH WILL INDUCE THE
SHEAR WILL ALSO ERODE THE SUBTROPICAL RIDGE. THE CYCLONE SHOULD
THEN SLOW DOWN AND TURN NORTHWARD AHEAD OF THE TROUGH. MOST OF THE
GUIDANCE IS CONSISTENT WITH THE WESTWARD MOTION TROUGH DAY 3 OR
SO...BUT AFTER THAT TIME...THE TRACK BECOMES HIGHLY UNCERTAIN WITH
SOME MODELS KEEPING THE CYCLONE MEANDERING...AND OTHERS MOVING IT
NORTHWARD A LITTLE FASTER. THE FIRST SOLUTION IS THE MOST LIKELY
SCENARIO TO OCCUR SINCE BY THAT TIME...RAYMOND SHOULD BE WEAKER AND
STEERED BY A MUCH LIGHTER LOW-LEVEL FLOW.


FORECAST POSITIONS AND MAX WINDS

INIT 25/0300Z 14.6N 107.7W 50 KT 60 MPH
12H 25/1200Z 14.5N 109.2W 55 KT 65 MPH
24H 26/0000Z 14.0N 111.5W 60 KT 70 MPH
36H 26/1200Z 13.7N 113.6W 65 KT 75 MPH
48H 27/0000Z 13.5N 116.0W 65 KT 75 MPH
72H 28/0000Z 14.0N 119.0W 65 KT 75 MPH
96H 29/0000Z 15.5N 120.0W 55 KT 65 MPH
120H 30/0000Z 17.0N 120.0W 45 KT 50 MPH

$$
FORECASTER AVILA

[ravyrn]

I doubt this system will become a major again. Only storm to become a MH then TS then MH in basin history was Doreen 73, though Trudy 90 was close.

Only time will tell.

[stormkite]

Raymond's definitely got some intense convention going on in the Nth band.




Personal Forecast Disclaimer:
The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.

[hurricanes1234]

Why hasn't Raymond begun to properly restrengthen yet? Advisory lowered it to 45 knots, but I can't understand why it would be weakening over hospitable conditions, except for minor shear. Does anyone think it will weaken from here? The NHC stated last night that one model forecasted no restrengthening, which is what is happening right now to a point. Could this lonesome model be correct in forecasting Raymond's lack of restrengthening?

[stormkite]

Why hasn't Raymond begun to properly restrengthen yet? Advisory lowered it to 45 knots, but I can't understand why it would be weakening over hospitable conditions, except for minor shear. Does anyone think it will weaken from here? The NHC stated last night that one model forecasted no restrengthening, which is what is happening right now to a point. Could this lonesome model be correct in forecasting Raymond's lack of restrengthening?

Just my 2 cents at 116/117 W - 13 N is where i think Raymond will reach hurricane strength again. I can't see any reason why it wont the centre is embedded there's 40 knot wind to enclose the dense overcast or quasi circular bands and 30 knot wind to enclose the outer vortex feeder bands.


Personal Forecast Disclaimer:
The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.