EPAC: SONIA - Tropical Depression

[hurricanes1234]

Storm2k is back!!!!!!


This is the thread for Tropical Depression 18E. Here is the latest Best Track.

EP, 18, 2013110218, , BEST, 0, 174N, 1096W, 30, 1006, TD

[hurricanes1234]

As we can see, the depression hasn't been doing very well, due to strong easterly shear. However, the shear may be letting up, according to the 8 AM discussion, and only a minor increase in winds would result in the formation of Tropical Storm Sonia. I think we'll see Sonia by tomorrow, the first 'S' storm here since 2006's Sergio!!!



000 WTPZ43 KNHC 021453 TCDEP3 TROPICAL DEPRESSION EIGHTEEN-E DISCUSSION NUMBER 6 NWS NATIONAL HURRICANE CENTER MIAMI FL EP182013 800 AM PDT SAT NOV 02 2013

CONVECTION HAS BEEN ON THE INCREASE ON THE NORTHWESTERN SIDE OF THE DEPRESSION...BUT VISIBLE SATELLITE IMAGES STILL SHOW THAT THE CENTER OF THE CYCLONE REMAIN WELL TO THE SOUTHEAST OF THE CONVECTIVE MASS. THERE HAS BEEN SOME EXPANSION OF THE CIRRUS CLOUDS EAST OF THE CENTER...SO PERHAPS THE EASTERLY SHEAR THAT HAS BEEN AFFECTING THE DEPRESSION IS ON THE WAY DOWN. THE INITIAL WIND SPEED WILL REMAIN 30 KT AS A BLEND OF THE TAFB/SAB DVORAK ESTIMATES.

THE DEPRESSION IS MOVING NORTHWESTWARD AT ABOUT 4 KT. A TURN TO THE NORTH THEN NORTH-NORTHEAST IS ANTICIPATED OVER THE NEXT COUPLE OF DAYS DUE TO AN APPROACHING CLOSED LOW. MODEL GUIDANCE REMAINS TIGHTLY CLUSTERED ON THIS TRACK...AND NO SIGNIFICANT CHANGES WERE MADE TO THE PREVIOUS FORECAST. A 72H FORECAST IS INCLUDED FOR CONTINUITY...BUT THE CYCLONE WILL LIKELY BE DISSIPATED BY THEN.

IT WOULD NOT TAKE MUCH OF AN INCREASE IN WINDS FOR THE DEPRESSION TO BECOME A LOW-END TROPICAL STORM...AND THE LATEST GUIDANCE DOES HAVE A COUPLE OF MORE MODELS THAT SHOW THIS SOLUTION. THUS THE NEW FORECAST WILL CONTINUE TO SHOW MODEST STRENGTHENING. SOUTHWESTERLY WIND SHEAR IS EXPECTED TO RAPIDLY INCREASE AFTER 36H...WHICH SHOULD CAUSE THE CYCLONE TO WEAKEN WHILE ITS APPROACHES MAINLAND MEXICO. THE NEW NHC FORECAST IS NOT FAR FROM THE PREVIOUS ONE...WITHIN A FEW KNOTS OF THE MODEL CONSENSUS.

GIVEN THE CURRENT LACK OF ORGANIZATION AND THE LOW CHANCES OF SIGNIFICANT STRENGTHENING...THE CYCLONE IS UNLIKELY TO CAUSE TROPICAL-STORM-FORCE WINDS OVER MEXICO. THUS...IT IS PRUDENT TO WAIT FOR ANY TROPICAL STORM WATCHES AT THIS TIME. HOWEVER INTERESTS IN BAJA CALIFORNIA SUR AND SINALOA SHOULD MONITOR THIS SYSTEM. FORECAST POSITIONS AND MAX WINDS
INIT 02/1500Z 17.6N 109.1W 30 KT 35 MPH
12H 03/0000Z 18.3N 109.8W 35 KT 40 MPH
24H 03/1200Z 19.6N 110.0W 35 KT 40 MPH
36H 04/0000Z 21.9N 109.2W 35 KT 40 MPH
48H 04/1200Z 24.8N 107.8W 30 KT 35 MPH...INLAND
72H 05/1200Z 28.5N 105.0W 15 KT 15 MPH...POST-TROP/REMNT LOW
96H 06/1200Z...DISSIPATED

$$
FORECASTER BLAKE

[supercane4867]

Storm2k is back!!!!!!

After two days of frustration for me...finally back

[hurricanes1234]

As of lately, the center has been moving closer to the convection, a sign of lessening shear. Can this finally get its act together and become Sonia?

[hurricanes1234]

Seventh advisory without TS. The discussion says it might be stronger though.

[hurricanes1234]

T-numbers sharply increasing as of 20:30 UTC.

Final T# Adj T# Raw T#
2.3 2.7 2.8

[TropicalAnalystwx13]

I'd say this has become TS Sonia. Despite the sheared appearance, the depression has been producing very deep convection west of the center. I doubt winds are less than 35kt in there.

[hurricanes1234]

I'd say this has become TS Sonia. Despite the sheared appearance, the depression has been producing very deep convection west of the center. I doubt winds are less than 35kt in there.

ADT agrees. 21:30UTC estimates support tropical storm status.

CI# /Pressure/ Vmax
2.5 /1005.6mb/ 35.0kt

[cycloneye]

BULLETIN
TROPICAL DEPRESSION EIGHTEEN-E INTERMEDIATE ADVISORY NUMBER 7A
NWS NATIONAL HURRICANE CENTER MIAMI FL EP182013
500 PM PDT SAT NOV 02 2013

...DEPRESSION EXPECTED TO PASS NEAR THE SOUTHERN TIP OF THE BAJA
CALIFORNIA PENINSULA SUNDAY NIGHT...


SUMMARY OF 500 PM PDT...0000 UTC...INFORMATION
----------------------------------------------
LOCATION...17.9N 109.9W
ABOUT 345 MI...555 KM S OF THE SOUTHERN TIP OF BAJA CALIFORNIA
ABOUT 500 MI...805 KM SSW OF CULIACAN MEXICO
MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H
PRESENT MOVEMENT...NW OR 310 DEGREES AT 6 MPH...9 KM/H
MINIMUM CENTRAL PRESSURE...1006 MB...29.71 INCHES

WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY...

NONE.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT...

A TROPICAL STORM WATCH IS IN EFFECT FOR...
* TOPOLOBAMPO TO LA CRUZ

A TROPICAL STORM WATCH MEANS THAT TROPICAL STORM CONDITIONS ARE
POSSIBLE WITHIN THE WATCH AREA...GENERALLY WITHIN 48 HOURS.

INTERESTS IN BAJA CALIFORNIA SUR AND ELSEWHERE IN WEST-CENTRAL
MAINLAND MEXICO SHOULD MONITOR THE PROGRESS OF THIS SYSTEM.

FOR STORM INFORMATION SPECIFIC TO YOUR AREA...PLEASE MONITOR
PRODUCTS ISSUED BY YOUR NATIONAL METEOROLOGICAL SERVICE.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 500 PM PDT...0000 UTC...THE CENTER OF TROPICAL DEPRESSION
EIGHTEEN-E WAS LOCATED NEAR LATITUDE 17.9 NORTH...LONGITUDE 109.9
WEST. THE DEPRESSION IS MOVING TOWARD THE NORTHWEST NEAR 6 MPH...9
KM/H. A TURN TOWARD THE NORTH AND NORTH-NORTHEAST WITH AN INCREASE
IN FORWARD SPEED ARE EXPECTED BY LATE SUNDAY. ON THE FORECAST
TRACK...THE CENTER OF THE CYCLONE WILL PASS NEAR THE SOUTHERN TIP
OF THE BAJA CALIFORNIA PENINSULA BY SUNDAY NIGHT...AND APPROACH THE
COAST OF MAINLAND MEXICO WITHIN THE WATCH AREA ON MONDAY.

MAXIMUM SUSTAINED WINDS ARE NEAR 35 MPH...55 KM/H...WITH HIGHER
GUSTS. THE DEPRESSION COULD BECOME A TROPICAL STORM TONIGHT OR
SUNDAY.

THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 1006 MB...29.71 INCHES.


HAZARDS AFFECTING LAND
----------------------
WIND...TROPICAL STORM CONDITIONS ARE POSSIBLE IN THE WATCH AREA
BY EARLY MONDAY.


NEXT ADVISORY
-------------
NEXT COMPLETE ADVISORY...800 PM PDT.

$$
FORECASTER BRENNAN

[supercane4867]

Still TD

EP, 18, 2013110300, , BEST, 0, 179N, 1100W, 30, 1006, TD

[hurricanes1234]

My question is if this will ever become a TS. It really doesn't need even 5 mph to strengthen to that status, so what's the holdup now? If things don't change by the next advisory, we'll be on our eighth advisory as a depression. And time is running out before that shear abruptly increases. Chances are dwindling with each 6 hour period.

[hurricanes1234]

Looks just as sheared apart as it was last night. I guess we're back to Square 1, which is nothing but a weak depression struggling amidst persistent shear. I now have little optimism this would become Sonia tonight.

[TropicalAnalystwx13]

Yikes. Not looking so good right now...the center appears to be drifting northeast as convection weakens.

ASCAT is bent on missing the western side of this thing.

[Yellow Evan]

I doubt this will become a TS. It appears 2009 will remain the dead era (1995-) record for most storm since 1994.

[hurricanes1234]

I doubt this will become a TS. It appears 2009 will remain the dead era (1995-) record for most storm since 1994.

This depression is really sad, I also anticipate no TS from this. Yes the shear is lessening - etc. etc. etc., but we've been saying this for in excess of 24 hours now with nothing but the same 30 knots/1006 mbar. I can't understand why it didn't strengthen today, since that was the ideal time to do so. The center going closer to the convection really doesn't make a difference if the system isn't intensifying. Now it's even further away from whatever skeletal convection that remains, again with multiple vortices. Virtually hopeless now, in my opinion, unless it can pull a surprise and briefly gain TS strength at diurnal maximum. Another system fails to strengthen despite generally favourable conditions.


NOT OFFICIAL!

[Cyclenall]

Another post-season upgrade incoming...

[TropicalAnalystwx13]

It's a no-go for TS Sonia for now. An ASCAT-B pass from an hour ago showed 30kt winds in the convection. The center is on the very southeast side.

[Yellow Evan]

I doubt this will become a TS. It appears 2009 will remain the dead era (1995-) record for most storm since 1994.

This depression is really sad, I also anticipate no TS from this. Yes the shear is lessening - etc. etc. etc., but we've been saying this for in excess of 24 hours now with nothing but the same 30 knots/1006 mbar. I can't understand why it didn't strengthen today, since that was the ideal time to do so. The center going closer to the convection really doesn't make a difference if the system isn't intensifying. Now it's even further away from whatever skeletal convection that remains, again with multiple vortices. Virtually hopeless now, in my opinion, unless it can pull a surprise and briefly gain TS strength at diurnal maximum. Another system fails to strengthen despite generally favourable conditions.


NOT OFFICIAL!

There were not favorable really, it was only projected to reach 40 knts. It's somewhat amazing that we even got this far, it is rare nowadays to have a system over the Day of the Dead or latter. TC's can't form year around after all. Weather-wise, I've got several months of exciting from 2013. Bring on the winter before the SHEM gets going around Xmas.

[supercane4867]

Recent ASCAT showing flagged 50kt+ wind under the blow up of convection

[Extratropical94]

No post-season upgrade, but an in-season upgrade.

...DEPRESSION STRENGTHENS INTO TROPICAL STORM SONIA JUST
EAST OF SOCORRO ISLAND...
...TROPICAL STORM WARNING ISSUED FOR PORTIONS OF NORTHWESTERN
MEXICO...